Why Ethanol Is Brown
In 2010, 119 million metric tonnes of the U.S. corn crop (out of 400 million metric tonnes; between one third and one fourth of the total) went to make ethanol. This sent corn prices near record highs.
U.S. corn production has been rising at 2% a year for 30 years, mostly from plant breeding. (The limits of using more and more fertilizer were reached earlier). The crop went from 4 billion bushels in 1970 to 10 billion bushels in 2000.
In 2008 the U.S. corn crop was 12.8 billion bushels. About 40% went to feed animals, 30% for ethanol, 8% was processed for starch, corn oil and sweeteners, 15% was exported (mostly for animal feed). The sweeteners include high fructose corn syrup, a mixture of glucose and fructose which is used to sweeten sodas and processed foods. Fructose is the sugar found in honey and fruits. Unlike glucose (our main source of sugar) it doesn’t promote the release of insulin from pancreatic cells (the cells lack receptors for fructose) and thus doesn’t lead to the biochemical cascade that results in the secretion of leptin, the hormone that tells us we are full (stop eating!). Ingesting lots of fructose (as in soft drinks) leads to weight gain and the associated insulin resistance (which may be a direct result of too much fructose) and Type II diabetes. High fructose corn syrup is cheap and so products sweetened with it are cheap, but full of calories: a disaster—cheap unhealthy foods. We live in a world where buying a candy bar makes more sense than buying an apple.
Michael Pollan describes the miasmic smell of a cattle feedlot hanging over the Kansas plains. The cattle, fattened on a food (corn) to which they are not adapted, are maintained on low dose antibiotics, and develop life threatening strains of e coli in their intestines (life threatening to us, not to the cattle): the bugs disappear when the cattle are fed hay.
The corn is grown as a monoculture (nothing but corn in sight), fed with manufactured nitrogen fertilizer synthesized from natural gas, protected from competition with weeds by herbicides and from insects by pesticides. Resistance to the most popular herbicide, along with some insect killing toxins, are built into the genetically altered corn plants, whose seed is obtained from the manufacturer of the herbicide (a nifty deal for the seed-producing manufacturer).
Because of the petrochemicals (fertilizer, diesel fuel, pesticide) used to grow corn, and because of the energy required to distill it, ethanol is energy neutral or energy negative: that is, more energy goes into making ethanol than it contains. (Not very green.)
On a regenerative farm, rotating row crops with hays improves the tilth of soils, stores carbon, provides most of the nutrients for the following crops. The hay is sold or used to feed cattle.
Industrial corn is not rotated with hays. It is often rotated with soybeans (another animal feed). Both corn and soybeans are row crops whose fields shed topsoil into streams. Soybeans fix nitrogen from nitrogen gas in the atmosphere (making it usable to plants) but only enough for their own use. The manure the feedlot cattle produce is not used to fertilize the corn that feeds them (the corn is grown 100-1000 miles away). Some manure is processed into animal feed, some is spread (far too heavily) on nearby fields.
The extra nutrients from the feedlots and from the fields of corn and soybeans, along with topsoil (a bushel of topsoil for a bushel of corn), herbicides and pesticides, are carried by rain into rivers and streams; some seep down into groundwater, or volatilize into the air. (Herbicides from middle western farms are detectable in spring rains in the northeastern United States.)
Excess nutrients in streams cause algae to grow and reproduce. The algae are always there (they are a basis of the streams’ food chain) but their growth is limited by nutrients and by predation from small animals (zooplankton), which are eaten (as are the algae) by fish.
The flood of nutrients from corn and soybean fields, along with their topsoil, overwhelms the natural systems of streams. Water clouded with algae and silt shades out rooted underwater plants that hold and oxygenate bottom sediments and serve as nurseries for fish. The fish populations change from sight feeders (game fish like bass and pike) to bottom feeders like European carp that locate prey by touch and smell; or to fish that filter algae from the water column (two species of Asian carp that escaped from catfish farms in the Mississippi drainage). Overfertilized lakes and rivers stink, as the algae dies and sinks to the bottom. Most rivers in American farm country (reported by early travellers as clear) are murky with algae and silt. The silt settles out behind dams, shortening their lives.
The nutrients, pesticides and herbicides are carried by rivers to the sea. “Dead zones” off the coasts of developed countries are common. Decaying algae deprive the water of oxygen; few fish or invertebrates can survive. Herbicides injure water plants and riverside trees. As estuaries like Chesapeake Bay are overwhelmed by nitrogen and their sea grass meadows die, they lose their value as nurseries for marine fish; oysters disappear; they become dominated by algae and jellyfish (a predator of algae).
Much of this can be traced to poor farming practices: soybeans, corn, ethanol.
Ethanol production (like corn production) is subsidized. Its use in motor fuels is mandated. That it takes more energy to produce than it contains is ignored (a technical problem). This is a wonderful story for corn farmers (who have seen the price of corn near record levels), for the agribusinesses that distill ethanol, for the government whose support payments are no longer necessary. Perhaps less wonderful for drivers, who see their mileage fall while the price of motor fuel remains the same, and may have damage to their vehicles through improperly mixed fuels.
The agricultural support system that began under Franklin Roosevelt (the ever-normal granary; a very old concept of ensuring a food supply) limited the acreage of crops that could be grown on a farm. In return, the government would buy up the surplus at a reasonable price and resell it on the market when demand allowed. Thus the supply of grain would be maintained at a price that profited farmers; and enough grain would be available to feed the population.
Rising food prices under President Nixon forced a change in this policy: farmers were encouraged to grow as much as they could. The government would support the price at the cost of production. So farmers expanded their plantings. (Some conservation limits have been imposed recently.) Ethanol offered a way out of low corn prices caused by the continually expanding corn crop.
Suppose, instead of ethanol, or corn, biologically appropriate farming were subsidized. Farmers would be encouraged to grow an amount of grain their landscape could absorb; that would keep topsoil and nutrients on their fields and out of streams. Their fields would be part of a biologically working landscape, with herbivores (rabbits and deer), predators (foxes and coyotes), songbirds, hawks, amphibians, insects.
From 15% to 40% of such farms would be natural landscape—forest, desert, prairie. These landscapes store carbon (worth, say, $25-$50 an acre) and harbor insects, bats and birds and small predators that help the farmer. (When the farmers of Kern County, California, managed to exterminate their coyotes, the resulting overpopulation of mice chewed their way through their crops.) This natural land might be beside streams. If not, a band of hayfield or lightly grazed pasture 100-300 feet wide should border streams.
Where possible (providing water is a problem), cattle are grazed several months of the year on rotational pastures—small plots grazed for three days or a week, then rested for a month or six weeks. (The pastures are sometimes grazed after the cattle by chickens, which eat the hatching fly larvae out of the manure, spreading the manure in the process.) Grassland birds, the most endangered in the United States today, and ducks, breed in rotational pastures (the cattle graze around their nests). Modern hayfields are cut too often for successful nesting. Game birds and animals are part of farms with natural habitat and spilled grain. Canada Geese are attracted to the Chesapeake region by the spilled corn (about 10% of the crop) left in the fields. Prairie chickens probably increased in numbers as the prairie was settled, and more food was available in farmers’ fields, then disappeared as the larger landscape was reduced to grain fields and they lost their breeding grounds. Quail nest in damp thickets in Carolina corn and soybean fields. So hunting rights can be leased; and farms become attractive places to visit.
Row crops on the regenerative farm are rotated with hays. A third of the cultivated ground is in hays at any one time. (The corn crop is now down by a half to a third and the price of corn is as high as now.) Cattle are brought back to the farm to eat the hays, their manure used to grow the farm’s crops.
Cattle are grazed on small rotating pastures in summer and fall, fed baled hay in winter. Pigs are raised in large hoop houses bedded with hay, free to root, socialize, build great communal nests in the hay. After they are slaughtered, the hay and manure is scraped up and spread on the fields; or the house moved and the ground used to grow vegetables.
The corn stalks and cobs from fields harvested for grain are chopped and partially burned in a kiln to provide heat for the farmer’s house (hot tub, greenhouse) and biochar, a fine charcoal. Biochar increases the productivity of soils (some claim by several times) by storing and releasing nutrients (thus reducing losses through leaching). It locks up the carbon in the corn stalks for tens of thousands of years.
With the right management regenerative farms can grow food, improve soils, provide habitat for wild animals and store carbon.
The streams that run through the farm are clear and swimmable; the ocean estuaries and marine fisheries (with limits on fishing and fishing gear and large protected areas) recovering.
Green dreams! What corporation will profit? And population continues to grow, the demand for meat and grain with it…
Friday, March 4, 2011
Saturday, February 19, 2011
Biology Comics
The Roman Empire
The first conquests of the Roman Empire were in the East and immensely profitable. These old Mediterranean civilizations were rich and could afford much tribute. The profits funded new conquests.
Most of Italy was forested in BC 300. The newly cleared lands yielded large crops. The richness of the Italian soil was another basis of the Empire.
The western lands (Gaul, Spain, England, the Rhineland), which were conquered last, did not pay the costs of conquest. These lands were lightly settled and poor. While their soils were good, the cost of transporting crops like wheat overland was too great.
The Roman economy was overwhelmingly agricultural. Trade and industry were perhaps 10% of the economy. Once the conquests were over (about AD 1) agriculture had to pay the costs of administration.
A smallholder of the early Republic cultivated a hectare by hand with a hoe, growing olives, vines, fruit trees, grains, vegetables, forage crops and animals. The multistory canopy saved labor, reduced erosion, and was twice as productive in foodstuffs as plowing with an ox to grow grain. Some farmers applied manure, human manure, crushed limestone and ashes to their fields and grew cover crops on the grain fields left fallow every other year.
For large landowners plowing with oxen to grow grain was more profitable than hoe agriculture. While good farming practices were known, most large farmers didn’t follow them. In the two field system of the Greeks that was taken over by the Romans, land was plowed three times a year, whether cultivated or fallow, to control weeds. Erosion from plowland near Rome has been estimated at three quarters to four inches per century.
Iron had come into common use in Italy by BC 500 (for shovels, plow points and other tools) and forests were cut to smelt it, to fire pottery and burn brick. Trees were also cut for building material. Eroded soils from forests slid down the hillsides to the valley bottoms. Forests were often grazed after being cut.
As the more wealthy began to dominate Roman society after BC 200, large estates began to replace smallholdings, especially in the countryside around Rome. This landscape, the Campagna, fed the city until about BC 200.
Wheat, oil and wine could be profitably shipped by sea. The conquest of Egypt, with its soils renewed by the Nile, and the new lands of North Africa, let Rome feed itself after AD 1. The Imperial Middle East was completely deforested by AD 100 however and most of its upland soils were degraded by AD 200. Grazing replaced the cultivated grainland, which had replaced the forests. By the end of the Empire the silt carried by the Nile fed Rome. (The same African silt and the new lands of Sicily had also fed the declining Greek states 1000 years before.)
Land itself was taxed. No provision was made for varying yields. The government financed itself on a cash basis. Its single tax was inelastic and made it difficult to raise additional funds in time of need (as in war). Emperors in need of money debased the currency, an indirect tax.
Tenant farmers were taxed too highly to accumulate capital. When crops failed they abandoned their lands and left for Rome, where Egyptian wheat was distributed free to the citizens (the dole).
As more land fell into the hands of the large landowners, erosion increased. As yields fell, taxes became more difficult to pay and more and more land was abandoned. Abandoned land reached a third to a half of some provinces. Tax receipts collapsed. In AD 300 abandoned lands in the Campagna were estimated at 75,000 smallholdings. Taxes were doubled AD 324-364.
Eroded soil turned river valleys into marshlands. Malaria became a problem after AD 200. Malaria increases child mortality and reduces people’s capacity to work. In time, both slopes and valley bottoms were used for pasture rather than cultivated.
With the end of the conquests and the money they brought in, and the declining agricultural yields, and thus declining tax revenues, Rome no longer worked. The population of the Empire never recovered from the plague of the AD 160s. With the barbarian invasions of the AD 200s (crops destroyed, people killed and enslaved, animals killed or stolen), Rome began to go bankrupt. The literacy rate fell, but the size of the army and bureaucracy increased. The army was more and more staffed by barbarians.
As large estates further consolidated (city magistrates, whose position had become hereditary, had to pay the cost of city services), and plowed lands increased, yields fell further, and the countryside grew emptier. It now took ten times the land to feed a Roman than in the days of the early Republic. (Five hundred years of erosion would have reduced topsoil in the Campagna by 4 to 20 inches, and more on sloping lands.) Laws tied tenants to the land to prevent them from abandoning it. What the land needed to become productive was known; perhaps the larger structural problems of the Empire were also known. The western provinces were let go AD 260-274. By the late 300s, the Romans waited—as the poet Cavafy said—for the barbarians to deliver them from the Empire.
(In this essay I am indebted to The Collapse of Complex Societies by Joseph Tainter and Dirt by David Montgomery.)
The first conquests of the Roman Empire were in the East and immensely profitable. These old Mediterranean civilizations were rich and could afford much tribute. The profits funded new conquests.
Most of Italy was forested in BC 300. The newly cleared lands yielded large crops. The richness of the Italian soil was another basis of the Empire.
The western lands (Gaul, Spain, England, the Rhineland), which were conquered last, did not pay the costs of conquest. These lands were lightly settled and poor. While their soils were good, the cost of transporting crops like wheat overland was too great.
The Roman economy was overwhelmingly agricultural. Trade and industry were perhaps 10% of the economy. Once the conquests were over (about AD 1) agriculture had to pay the costs of administration.
A smallholder of the early Republic cultivated a hectare by hand with a hoe, growing olives, vines, fruit trees, grains, vegetables, forage crops and animals. The multistory canopy saved labor, reduced erosion, and was twice as productive in foodstuffs as plowing with an ox to grow grain. Some farmers applied manure, human manure, crushed limestone and ashes to their fields and grew cover crops on the grain fields left fallow every other year.
For large landowners plowing with oxen to grow grain was more profitable than hoe agriculture. While good farming practices were known, most large farmers didn’t follow them. In the two field system of the Greeks that was taken over by the Romans, land was plowed three times a year, whether cultivated or fallow, to control weeds. Erosion from plowland near Rome has been estimated at three quarters to four inches per century.
Iron had come into common use in Italy by BC 500 (for shovels, plow points and other tools) and forests were cut to smelt it, to fire pottery and burn brick. Trees were also cut for building material. Eroded soils from forests slid down the hillsides to the valley bottoms. Forests were often grazed after being cut.
As the more wealthy began to dominate Roman society after BC 200, large estates began to replace smallholdings, especially in the countryside around Rome. This landscape, the Campagna, fed the city until about BC 200.
Wheat, oil and wine could be profitably shipped by sea. The conquest of Egypt, with its soils renewed by the Nile, and the new lands of North Africa, let Rome feed itself after AD 1. The Imperial Middle East was completely deforested by AD 100 however and most of its upland soils were degraded by AD 200. Grazing replaced the cultivated grainland, which had replaced the forests. By the end of the Empire the silt carried by the Nile fed Rome. (The same African silt and the new lands of Sicily had also fed the declining Greek states 1000 years before.)
Land itself was taxed. No provision was made for varying yields. The government financed itself on a cash basis. Its single tax was inelastic and made it difficult to raise additional funds in time of need (as in war). Emperors in need of money debased the currency, an indirect tax.
Tenant farmers were taxed too highly to accumulate capital. When crops failed they abandoned their lands and left for Rome, where Egyptian wheat was distributed free to the citizens (the dole).
As more land fell into the hands of the large landowners, erosion increased. As yields fell, taxes became more difficult to pay and more and more land was abandoned. Abandoned land reached a third to a half of some provinces. Tax receipts collapsed. In AD 300 abandoned lands in the Campagna were estimated at 75,000 smallholdings. Taxes were doubled AD 324-364.
Eroded soil turned river valleys into marshlands. Malaria became a problem after AD 200. Malaria increases child mortality and reduces people’s capacity to work. In time, both slopes and valley bottoms were used for pasture rather than cultivated.
With the end of the conquests and the money they brought in, and the declining agricultural yields, and thus declining tax revenues, Rome no longer worked. The population of the Empire never recovered from the plague of the AD 160s. With the barbarian invasions of the AD 200s (crops destroyed, people killed and enslaved, animals killed or stolen), Rome began to go bankrupt. The literacy rate fell, but the size of the army and bureaucracy increased. The army was more and more staffed by barbarians.
As large estates further consolidated (city magistrates, whose position had become hereditary, had to pay the cost of city services), and plowed lands increased, yields fell further, and the countryside grew emptier. It now took ten times the land to feed a Roman than in the days of the early Republic. (Five hundred years of erosion would have reduced topsoil in the Campagna by 4 to 20 inches, and more on sloping lands.) Laws tied tenants to the land to prevent them from abandoning it. What the land needed to become productive was known; perhaps the larger structural problems of the Empire were also known. The western provinces were let go AD 260-274. By the late 300s, the Romans waited—as the poet Cavafy said—for the barbarians to deliver them from the Empire.
(In this essay I am indebted to The Collapse of Complex Societies by Joseph Tainter and Dirt by David Montgomery.)
Thursday, February 10, 2011
Biology Comics
Barges
Recent figures indicate one gallon of diesel will move a ton of cargo 59 miles by truck, 202 miles by train, 514 miles by canal barge (a single barge can carry 3000 tons or 100 truck loads).
Barges use rivers as highways. They motor through the still waters behind the dams, passing each dam in locks. On the Rhine, narrow canal boats carrying bulk cargoes push their way upstream through the currents.
By converting rivers into highways dams interrupt the flow of water, sediment and detritus along the stream. Flooding riverside wetlands eliminates their capacity to remove nutrients from water flowing into the river. Dams prevent fish migrations (and thus migrations of mussels, their glochidia transported by swimming fish). The water above dams is warmer, that below dams (released from the bottom of the reservoir) colder, thus changing the temperature cues the eggs and larvae of riverine invertebrates and fish use for hatching and development. (So they grow too early or too late—both want to develop when abundant food of the right size is available). The levees with which dams are associated prevent floods and limit the spawning of fish, many species of which prefer to spawn on flooded habitats. Dams alter the timing and abundance of flows to ocean estuaries, upon which marine fish (many of which spawn in nearshore waters) depend. Silt and silicon stored behind dams change the relative abundance of algal species in estuaries; less sand downstream causes erosion of beaches.
Dams also let people harvest river water to drink, bathe, fill swimming pools; to use in industry; to cool power plants; to irrigate crops. Together with levees, dams let people farm riverside land (much of which was farmable before dams, with free fertility provided by the river); build houses and cities near the river; and use the river to move freight.
The Romans thought the air, the waters, the ocean, the shores of the sea could not be owned. Under the Public Trust Doctrine (which the United States received through English common law from Roman Law), public assets, such as shore and river banks, are held by government for the common good. Similarly, the authority of the state to regulate wildlife derives from its authority to protect common resources. It would be much simpler to see where these matters lead us if we depended more directly on an abundance of wildlife and fish. But we have extinguished both for the ‘common good’ of economic development.
While fossil fuels let us lead lives separate from nature, our dependence on nature is clear, if poorly understood. For instance, trees and photosynthetic bacteria maintain the oxygen levels in the atmosphere, microbes, fungi, and invertebrates recycle the carbon (the lignins and carbohydrates) the plants produce annually, and many interconnected systems maintain the climate. Our dependence on nature is a dependence on ecological process.
The ‘common welfare’ includes the taking of water from rivers for human use, the right of fish to water (so they remain a resource for fishers), the right of beaches to sand (so beach goers, and the owners of houses that back the beach, may enjoy them). In an ideal world, the beach deserves sand and the fish water (and water a place in rivers; and even oil a place in its underground reservoirs), whether or not any human advantage flows from them. (But the advantage is that a given system works in a more or less predictable way—which is not to say it cannot be disturbed—by volcanic eruptions cooling or warming the earth; by landslides damming rivers.)
Some rivers no longer reach the sea (the Colorado, the Yangtze). All their water is used by people. So marine fish are deprived of deltas and estuaries to spawn and mature in, offshore waters of nutrients. Many rivers no longer flood so native fish have trouble surviving (the Mississippi-Misssouri, the Colorado, the Rhine). Or are so polluted with silt and nutrients their fish (mussel, invertebrate, waterbird, turtle) populations crash and other organisms take over. The Illinois, a booming native fishery a century ago is now dominated by two filter feeding Chinese carp, escapees from fish farms, that thrive in the turbid water, and terrify boaters and water skiers by leaping up as they pass—part of the fishes’ strategy for escaping predators.
A rule of thumb for functioning rivers is that no more than 20-25% of longterm average flow should be withdrawn; and less during droughts.
Such numbers cannot be applied to rivers like the Colorado, all of whose water is subscribed to human use. (In fact, more Colorado water is allocated than exists, since the early 20th century years used as a benchmark to determine its flow were unusually wet ones).
Like the Mississippi-Missouri, the Columbia, or the Rhine (each remade in its own way), the Colorado is a totally remade river. Once silty and unpredictable, it now has long reaches of clear cold water and a more even flow. It is twice as salty as before. (The yearly flow of the river before dams varied from 4 million acre-feet to 24 million acre-feet, an enormous range; an acre-foot is the water necessary to cover an acre a foot deep.)
Large dams transformed the Colorado. Irrigation of rancher’s hayfields along its upstream tributaries began to change it. The concrete plug of Hoover Dam stopped any movement of fish upstream from the lower river. That part of the river, below the canyons, where the Yuma once planted their corn in the wet mud left by the receding floods (the corn matured in 60 days) flowed through an wide riparian valley of marshes and backwaters, fed on silt, rearranged by floods. The backwaters were places young pike-minnow and other native fish (razorback sucker, humpbacked sucker, bonytailed chub) matured. Pike-minnow were the top predatory fish in the Colorado, reaching 6 feet in length and 80 pounds. Pike-minnow spawned in the clean gravel and cobble left by the spring floods, matured in backwaters, migrated 300 miles up and down the river to seek optimal places for spawning and survival. Like the other fish of the Colorado and its tributaries they were adapted to the warm low silty flows of summer and the turbulent spring floods, when water volumes might increase by 100 times.
The marshes and backwaters along the lower river have been consolidated into a 150 yard wide stream held back by Parker dam at the Mexican border. The water irrigates fields on either side. Protected by dam operations and levees, houses have crept up to the edge of the river, which is no longer allowed to flood.
The Delta of the Colorado in the Gulf of California once consisted of 2 million acres of fresh and tidal wetlands. (Aldo Leopold wrote a memoir of a bow hunting trip there with his brother.) A desert delta, it was an important habitat for west coast waterbirds. Shrimp and other invertebrates of the delta supported the marine fish and birds of the Gulf of California. Now starved of silt and water (wet years in the 1980s restored about 150,0000 acres of the marshes), its place in the avian world has been taken over by the Salton Sea, a desert sink that was filled by the Colorado early in the 20th century when the river abandoned its normal course to take over an irrigation canal into California’s Imperial Valley. The water filled the sea during the several years it took to return the river to its bed. (That this had happened before is the subject of Native American tales.) The Salton Sea is now maintained by runoff from irrigated farms in the Imperial Valley (irrigated with Colorado water). Its increasing content of salts, fertilizers, metals and pesticides make it something of a disaster as a sanctuary for birds, which suffer (like the fish introduced from the gulf) from periodic epidemic diseases and dieoffs.
Allotting 5% of the Colorado water to the delta would restore a third of it (about 750,000 acres). Then plans to desalinate the Salton Sea (to maintain it as a bird habitat) could be abandoned and the money put into buying out water rights from farmers. Irrigation runoff would matter less, and farmers could shift to less water using, more valuable crops (say, to winter greens from alfalfa and cotton). All this would leave more water in the river, some of which would reach the delta.
Irrigation lets you ignore climate. Colorado water supports the alfalfa, cotton and lettuce fields of the Imperial Valley; the citrus plantations and spinach and cotton fields of Arizona. Many commodity crops (cotton, corn) grown under irrigation could be grown in sufficient quantity further east, with irrigation (if necessary) from streamside reservoirs dug beside the rivers. Small farmsize irrigation ponds store irrigation water, recharge underground aquifers, provide spawning places for fish and habitat for waterbirds and amphibians, especially if the water is pumped from shallow wells and not from the reservoirs themselves, with all their plant and animal life. Such reservoirs, storing no more than say 10% of the spring runoff, might improve the habitat of degraded eastern rivers. (Somewhat similarly, floodwaters from the Colorado could be stored in underground aquifers rather then in reservoirs behind dams, from which the water, exposed to the desert sun, evaporates.)
Drylands are often rich in nutrients which have been banked by plants and soil cyanobacteria, but not much used or leached by rain (nitrogen in dryland subsoils can reach toxic levels). Some dryland soils take to irrigation well. Many drylands however were once ocean bottom and are underlain by salts, which irrigation tends to draw upwards, and which must be constantly drained and flushed away. In the Wellton-Mohawk Irrigation District of Arizona, the Bureau of Reclamation sunk wells into the briny groundwater and piped it to the Colorado. Not allowed to raise the salt content of the river, they reduced its salt input in other ways—by lining canals, using more efficient irrigation systems, taking some lands with very salty subsoils out of production. I suppose if agriculture wouldn’t pay to desalinate the briny drainage water, marketing the salts and metals, and reusing the water for irrigation or returning it to the river, the agriculture wasn’t economic. But agriculture never pays the cost of large scale irrigation systems, which enrich private landowners with public monies, and degrade rivers.
Suppose for rivers like the Colorado we reverse the usual figure and say 25% of its water should be kept in the river to support its normal flood cycle and its wildlife. It is estimated that pressurized irrigation systems (drip tubing, sprinklers) that use less water (and more power but once you install the equipment solar power is free in the desert), shifting to crops of higher value that use less water (such as winter greens) and urban water conservation could save a third to a half of the water taken from the river. (The potential for household savings is huge but irrigation uses most of the water.) Then even more water could be left in the river and through a new treaty with Mexico, to whom the U.S. is currently obligated to release 1.5 million acre feet of Colorado water a year of a certain salinity (the last standard usually not met), the delta could be partially restored.
Rivers like the Colorado need to flood. Floods distribute sediment and nutrients to the floodplain, dig new channels and backwaters, renew the vegetation of cottonwood and willow. Floods maintain habitat for fish. The vegetation that sprouts on the newly bare ground feeds small mammals and water and game birds. While levels of heavy metals, pesticides and herbicides in the lower Colorado are high enough to cause reproductive problems in fish, the lack of floods and the changes in patterns of seasonal flow may be greater problems for the fish.
Glen Canyon Dam, the last major dam on the Colorado, was constructed to provide additional water storage for Lake Mead (the reservoir behind Hoover Dam). Evaporation from Lake Powell (the reservoir behind Glen Canyon Dam) is about a million acre-feet a year. Because of this, removing it would not cause much change in Lake Mead’s capacity to provide water. It’s removal would restore a more natural flow to a long reach of the river and let more water reach the delta. It would end the dam’s power generation (Glen Canyon Dam provides 3-4% of the electricity used in the four corners states); the power is useful because it can be switched on immediately when needed. It would also end the cold water fishery for rainbow trout below the dam (the trout feed on diatoms that thrive in the clear water) and the growing population of bald eagles that eat them. The silt behind Glen Canyon Dam is contaminated with mercury and selenium (as is the silt in Lake Mead), much of it leached from the basin’s sedimentary rocks. The dam also captures phosphorus (bound to the silt). The building of Glen Canyon Dam dramatically reduced the abundant artificial fishery in Lake Mead, which is based on phosphorus eating algae, algae eating gizzard shad and striped bass.
Letting the river flood below Hoover Dam would restore the lower river. Thanks to dam operations, levees and dredging, people now build up to the edge of the dredged river. About 123,000 acres of riparian vegetation remain along the lower Colorado (one fourth of the original), 23,000 of them in a natural state (5% of the original vegetation, then, the rest in introduced salt cedar which outcompetes cottonwoods and willows on salty, dry soils). Removing levees along contiguous parts of this (connecting the floodplain to the river) and letting the land flood would restore parts of the floodplain (then salt cedar is likely to become a part of the ecosystem, not a dominant). Some people would have to be bought out, which puts the government in the position of paying people to surrender what it paid to provide them.
A river disconnected from its flood plain no longer works. Without a floodplain, a river cannot store floodwaters, provide spawning habitat for fish, turn silt and nutrients into herbs and trees, adjust its bed to its flow and silt load, shelter abundant amphibians, song and water birds, and game animals, and provide water of an amount, timing, and with the nutrients, the fish and invertebrates in its delta expect.
By damming rivers and turning them into highways, we interfere with fundamental ecological process. Rivers can handle some interference but control beyond a point turns them into drains, barge highways, water delivery canals. Ecological process is what provides the fish and mussels in the river, the fish of the estuaries and the sea. Do people own the ecological processes that maintain our green world; or have a right to extinguish them?
We live more and more in a world separate from the rest of creation. The separate world always existed—all plants and animals create their own worlds, some more than others. The separate world became more so with cities and writing. It got a push forward with the printing press, the secularization of thought, the use of fossil fuels. Now most of us live in one separate world (that supported by fossil fuels), while scanning (through the internet) another. In these worlds what does nature matter? Who knows about it?
Moving freight by river barge takes less fuel but is biologically very expensive. If all the costs of maintaining the river as a highway were charged to the barges, it would be economically expansive too.
Human use and ownership of the landscape move along a continuum. One way to approach biological economics is to assign values to things (fish, forests, underground waters) that are extremely hard to value; and which receive very low values under modern economic theory (once used up, a resource will be replaced by something else); but whose loss is likely to have far-reaching effects (what will we drink?). I think an enlightened state should set biological limits through its interest in the common good; and let the cornucopian human economic society deal (as it will) with a much more limited landscape and resources.
(In this essay I am indebted to Restoring Colorado River Ecosystems by Robert Adler.)
Recent figures indicate one gallon of diesel will move a ton of cargo 59 miles by truck, 202 miles by train, 514 miles by canal barge (a single barge can carry 3000 tons or 100 truck loads).
Barges use rivers as highways. They motor through the still waters behind the dams, passing each dam in locks. On the Rhine, narrow canal boats carrying bulk cargoes push their way upstream through the currents.
By converting rivers into highways dams interrupt the flow of water, sediment and detritus along the stream. Flooding riverside wetlands eliminates their capacity to remove nutrients from water flowing into the river. Dams prevent fish migrations (and thus migrations of mussels, their glochidia transported by swimming fish). The water above dams is warmer, that below dams (released from the bottom of the reservoir) colder, thus changing the temperature cues the eggs and larvae of riverine invertebrates and fish use for hatching and development. (So they grow too early or too late—both want to develop when abundant food of the right size is available). The levees with which dams are associated prevent floods and limit the spawning of fish, many species of which prefer to spawn on flooded habitats. Dams alter the timing and abundance of flows to ocean estuaries, upon which marine fish (many of which spawn in nearshore waters) depend. Silt and silicon stored behind dams change the relative abundance of algal species in estuaries; less sand downstream causes erosion of beaches.
Dams also let people harvest river water to drink, bathe, fill swimming pools; to use in industry; to cool power plants; to irrigate crops. Together with levees, dams let people farm riverside land (much of which was farmable before dams, with free fertility provided by the river); build houses and cities near the river; and use the river to move freight.
The Romans thought the air, the waters, the ocean, the shores of the sea could not be owned. Under the Public Trust Doctrine (which the United States received through English common law from Roman Law), public assets, such as shore and river banks, are held by government for the common good. Similarly, the authority of the state to regulate wildlife derives from its authority to protect common resources. It would be much simpler to see where these matters lead us if we depended more directly on an abundance of wildlife and fish. But we have extinguished both for the ‘common good’ of economic development.
While fossil fuels let us lead lives separate from nature, our dependence on nature is clear, if poorly understood. For instance, trees and photosynthetic bacteria maintain the oxygen levels in the atmosphere, microbes, fungi, and invertebrates recycle the carbon (the lignins and carbohydrates) the plants produce annually, and many interconnected systems maintain the climate. Our dependence on nature is a dependence on ecological process.
The ‘common welfare’ includes the taking of water from rivers for human use, the right of fish to water (so they remain a resource for fishers), the right of beaches to sand (so beach goers, and the owners of houses that back the beach, may enjoy them). In an ideal world, the beach deserves sand and the fish water (and water a place in rivers; and even oil a place in its underground reservoirs), whether or not any human advantage flows from them. (But the advantage is that a given system works in a more or less predictable way—which is not to say it cannot be disturbed—by volcanic eruptions cooling or warming the earth; by landslides damming rivers.)
Some rivers no longer reach the sea (the Colorado, the Yangtze). All their water is used by people. So marine fish are deprived of deltas and estuaries to spawn and mature in, offshore waters of nutrients. Many rivers no longer flood so native fish have trouble surviving (the Mississippi-Misssouri, the Colorado, the Rhine). Or are so polluted with silt and nutrients their fish (mussel, invertebrate, waterbird, turtle) populations crash and other organisms take over. The Illinois, a booming native fishery a century ago is now dominated by two filter feeding Chinese carp, escapees from fish farms, that thrive in the turbid water, and terrify boaters and water skiers by leaping up as they pass—part of the fishes’ strategy for escaping predators.
A rule of thumb for functioning rivers is that no more than 20-25% of longterm average flow should be withdrawn; and less during droughts.
Such numbers cannot be applied to rivers like the Colorado, all of whose water is subscribed to human use. (In fact, more Colorado water is allocated than exists, since the early 20th century years used as a benchmark to determine its flow were unusually wet ones).
Like the Mississippi-Missouri, the Columbia, or the Rhine (each remade in its own way), the Colorado is a totally remade river. Once silty and unpredictable, it now has long reaches of clear cold water and a more even flow. It is twice as salty as before. (The yearly flow of the river before dams varied from 4 million acre-feet to 24 million acre-feet, an enormous range; an acre-foot is the water necessary to cover an acre a foot deep.)
Large dams transformed the Colorado. Irrigation of rancher’s hayfields along its upstream tributaries began to change it. The concrete plug of Hoover Dam stopped any movement of fish upstream from the lower river. That part of the river, below the canyons, where the Yuma once planted their corn in the wet mud left by the receding floods (the corn matured in 60 days) flowed through an wide riparian valley of marshes and backwaters, fed on silt, rearranged by floods. The backwaters were places young pike-minnow and other native fish (razorback sucker, humpbacked sucker, bonytailed chub) matured. Pike-minnow were the top predatory fish in the Colorado, reaching 6 feet in length and 80 pounds. Pike-minnow spawned in the clean gravel and cobble left by the spring floods, matured in backwaters, migrated 300 miles up and down the river to seek optimal places for spawning and survival. Like the other fish of the Colorado and its tributaries they were adapted to the warm low silty flows of summer and the turbulent spring floods, when water volumes might increase by 100 times.
The marshes and backwaters along the lower river have been consolidated into a 150 yard wide stream held back by Parker dam at the Mexican border. The water irrigates fields on either side. Protected by dam operations and levees, houses have crept up to the edge of the river, which is no longer allowed to flood.
The Delta of the Colorado in the Gulf of California once consisted of 2 million acres of fresh and tidal wetlands. (Aldo Leopold wrote a memoir of a bow hunting trip there with his brother.) A desert delta, it was an important habitat for west coast waterbirds. Shrimp and other invertebrates of the delta supported the marine fish and birds of the Gulf of California. Now starved of silt and water (wet years in the 1980s restored about 150,0000 acres of the marshes), its place in the avian world has been taken over by the Salton Sea, a desert sink that was filled by the Colorado early in the 20th century when the river abandoned its normal course to take over an irrigation canal into California’s Imperial Valley. The water filled the sea during the several years it took to return the river to its bed. (That this had happened before is the subject of Native American tales.) The Salton Sea is now maintained by runoff from irrigated farms in the Imperial Valley (irrigated with Colorado water). Its increasing content of salts, fertilizers, metals and pesticides make it something of a disaster as a sanctuary for birds, which suffer (like the fish introduced from the gulf) from periodic epidemic diseases and dieoffs.
Allotting 5% of the Colorado water to the delta would restore a third of it (about 750,000 acres). Then plans to desalinate the Salton Sea (to maintain it as a bird habitat) could be abandoned and the money put into buying out water rights from farmers. Irrigation runoff would matter less, and farmers could shift to less water using, more valuable crops (say, to winter greens from alfalfa and cotton). All this would leave more water in the river, some of which would reach the delta.
Irrigation lets you ignore climate. Colorado water supports the alfalfa, cotton and lettuce fields of the Imperial Valley; the citrus plantations and spinach and cotton fields of Arizona. Many commodity crops (cotton, corn) grown under irrigation could be grown in sufficient quantity further east, with irrigation (if necessary) from streamside reservoirs dug beside the rivers. Small farmsize irrigation ponds store irrigation water, recharge underground aquifers, provide spawning places for fish and habitat for waterbirds and amphibians, especially if the water is pumped from shallow wells and not from the reservoirs themselves, with all their plant and animal life. Such reservoirs, storing no more than say 10% of the spring runoff, might improve the habitat of degraded eastern rivers. (Somewhat similarly, floodwaters from the Colorado could be stored in underground aquifers rather then in reservoirs behind dams, from which the water, exposed to the desert sun, evaporates.)
Drylands are often rich in nutrients which have been banked by plants and soil cyanobacteria, but not much used or leached by rain (nitrogen in dryland subsoils can reach toxic levels). Some dryland soils take to irrigation well. Many drylands however were once ocean bottom and are underlain by salts, which irrigation tends to draw upwards, and which must be constantly drained and flushed away. In the Wellton-Mohawk Irrigation District of Arizona, the Bureau of Reclamation sunk wells into the briny groundwater and piped it to the Colorado. Not allowed to raise the salt content of the river, they reduced its salt input in other ways—by lining canals, using more efficient irrigation systems, taking some lands with very salty subsoils out of production. I suppose if agriculture wouldn’t pay to desalinate the briny drainage water, marketing the salts and metals, and reusing the water for irrigation or returning it to the river, the agriculture wasn’t economic. But agriculture never pays the cost of large scale irrigation systems, which enrich private landowners with public monies, and degrade rivers.
Suppose for rivers like the Colorado we reverse the usual figure and say 25% of its water should be kept in the river to support its normal flood cycle and its wildlife. It is estimated that pressurized irrigation systems (drip tubing, sprinklers) that use less water (and more power but once you install the equipment solar power is free in the desert), shifting to crops of higher value that use less water (such as winter greens) and urban water conservation could save a third to a half of the water taken from the river. (The potential for household savings is huge but irrigation uses most of the water.) Then even more water could be left in the river and through a new treaty with Mexico, to whom the U.S. is currently obligated to release 1.5 million acre feet of Colorado water a year of a certain salinity (the last standard usually not met), the delta could be partially restored.
Rivers like the Colorado need to flood. Floods distribute sediment and nutrients to the floodplain, dig new channels and backwaters, renew the vegetation of cottonwood and willow. Floods maintain habitat for fish. The vegetation that sprouts on the newly bare ground feeds small mammals and water and game birds. While levels of heavy metals, pesticides and herbicides in the lower Colorado are high enough to cause reproductive problems in fish, the lack of floods and the changes in patterns of seasonal flow may be greater problems for the fish.
Glen Canyon Dam, the last major dam on the Colorado, was constructed to provide additional water storage for Lake Mead (the reservoir behind Hoover Dam). Evaporation from Lake Powell (the reservoir behind Glen Canyon Dam) is about a million acre-feet a year. Because of this, removing it would not cause much change in Lake Mead’s capacity to provide water. It’s removal would restore a more natural flow to a long reach of the river and let more water reach the delta. It would end the dam’s power generation (Glen Canyon Dam provides 3-4% of the electricity used in the four corners states); the power is useful because it can be switched on immediately when needed. It would also end the cold water fishery for rainbow trout below the dam (the trout feed on diatoms that thrive in the clear water) and the growing population of bald eagles that eat them. The silt behind Glen Canyon Dam is contaminated with mercury and selenium (as is the silt in Lake Mead), much of it leached from the basin’s sedimentary rocks. The dam also captures phosphorus (bound to the silt). The building of Glen Canyon Dam dramatically reduced the abundant artificial fishery in Lake Mead, which is based on phosphorus eating algae, algae eating gizzard shad and striped bass.
Letting the river flood below Hoover Dam would restore the lower river. Thanks to dam operations, levees and dredging, people now build up to the edge of the dredged river. About 123,000 acres of riparian vegetation remain along the lower Colorado (one fourth of the original), 23,000 of them in a natural state (5% of the original vegetation, then, the rest in introduced salt cedar which outcompetes cottonwoods and willows on salty, dry soils). Removing levees along contiguous parts of this (connecting the floodplain to the river) and letting the land flood would restore parts of the floodplain (then salt cedar is likely to become a part of the ecosystem, not a dominant). Some people would have to be bought out, which puts the government in the position of paying people to surrender what it paid to provide them.
A river disconnected from its flood plain no longer works. Without a floodplain, a river cannot store floodwaters, provide spawning habitat for fish, turn silt and nutrients into herbs and trees, adjust its bed to its flow and silt load, shelter abundant amphibians, song and water birds, and game animals, and provide water of an amount, timing, and with the nutrients, the fish and invertebrates in its delta expect.
By damming rivers and turning them into highways, we interfere with fundamental ecological process. Rivers can handle some interference but control beyond a point turns them into drains, barge highways, water delivery canals. Ecological process is what provides the fish and mussels in the river, the fish of the estuaries and the sea. Do people own the ecological processes that maintain our green world; or have a right to extinguish them?
We live more and more in a world separate from the rest of creation. The separate world always existed—all plants and animals create their own worlds, some more than others. The separate world became more so with cities and writing. It got a push forward with the printing press, the secularization of thought, the use of fossil fuels. Now most of us live in one separate world (that supported by fossil fuels), while scanning (through the internet) another. In these worlds what does nature matter? Who knows about it?
Moving freight by river barge takes less fuel but is biologically very expensive. If all the costs of maintaining the river as a highway were charged to the barges, it would be economically expansive too.
Human use and ownership of the landscape move along a continuum. One way to approach biological economics is to assign values to things (fish, forests, underground waters) that are extremely hard to value; and which receive very low values under modern economic theory (once used up, a resource will be replaced by something else); but whose loss is likely to have far-reaching effects (what will we drink?). I think an enlightened state should set biological limits through its interest in the common good; and let the cornucopian human economic society deal (as it will) with a much more limited landscape and resources.
(In this essay I am indebted to Restoring Colorado River Ecosystems by Robert Adler.)
Friday, January 14, 2011
Biology Comics
Cornucopians and Malthusians
In 1980 Paul Ehrlich, a biologist (author of The Population Bomb), along with his colleagues the physicists John Harte and John Holdren, bet the economist Julian Simon on the future price of metals. Ehrlich bet the prices would increase as the better ores (those more accessible, with a higher metal content) were used up. Simon bet that metals would become cheaper and cheaper.
Simon won. In 1990 the prices of all five metals (copper, chromium, nickel, tin, tungsten) were lower.
While ores were poorer, processing methods became more efficient and the energy needed for processing got cheaper. The rise in metals prices (up to 1975) stimulated substitution of cheaper materials (as the use of plastic pipe instead of copper), which reduced demand for metals and kept their prices down (they had to compete).
Economics focuses on the human world. It teaches that the best use for resources is to exploit them as quickly as possible to economic extinction, then invest the profit in something else. As the resource becomes more scarce (and expensive) people will find alternatives and the human world will not suffer.
Malthusians point out that there is only so much of any resource (fresh water, ocean fish, fertile farmland, unpolluted air) and when they are gone what will we do. Some will be hard to substitute for.
Don’t worry, say the Malthusians—harvest the ocean for a tasty algal soup; adjust the climate to where we like it. If all else fails, we’re off to other worlds!
In the early nineteenth century Malthus’ concern was that population (which has the potential to grow geometrically) would always outgrow the supply of food (which grows slowly if at all). (The idea that animals produce far more young than can survive is one of the bases of evolution.) But at the time Malthus wrote the exploitation of fossil fuels was beginning. Fossil fuels let people build railroads to open up new farmland, ship food in steam powered steel ships all over the world, manufacture fertilizers, trawl distant seas. Over the next century and a half population grew by several times while world output (food and stuff) grew by several tens of times. Many more people became a lot more prosperous (even if some of them remain as poor as before). We could feed all those people a healthy diet even now, if food were fairly distributed.
So who’s right? Ehrlich? Simon? Both?
Simon refused to take a later bet Ehrlich proposed (his partner this time was the climatologist Stephen Schneider) in which Ehrlich focused on the resources themselves—the amount of fertile farmland per person, the extent of moist tropical forests, the global temperature, the number of species of plants and animals. Simon wouldn’t take the bet because he said that the degradation of the planet didn’t matter. Less farmland would be made up through fertilizer, or by producing food in other ways. The human habitat (the virtual world maintained by fossil fuels) would continue to improve. He used the analogy of the Olympics. While Ehrlich was betting the track would be worse, Simon was betting the times of the athletes would be better.
John Tierney, a journalist who writes a contrarian column in the Science Times of The New York Times recently described a bet with an oil expert, Matthew Simmons. In 2005 Simmons bet Tierney and his partner Rita Simon, Julian Simon’s widow, $5000 that the price of oil would average $200 or more in 2005 dollars in 2010. The price of oil rose to $145 by the summer of 2008 but fell with the global recession in the fall of 2008 to $50. The average price in 2010 was about $80. So again the cornucopians won (this time by chance).
Human affairs, like changes in climate, are unpredictable. I would bet Tierney that the level of carbon dioxide in the atmosphere in October 2015 measured from the Mauna Loa Observatory in Hawaii will be 398 ppmv or greater; that is, that carbon dioxide will continue to rise at 2 ppmv per year. Tierney, like Bjorn Lomborg, the skeptical environmentalist, thinks the effect of manmade carbon dioxide on climate will be minimal. (I could bet that one year between 2011 and 2015 will be either warmer or wetter, or both, than any since reliable measurements started in the 1880s.) Simon wouldn’t have taken my bet, because he wouldn’t have thought climatic conditions a matter of his concern. Human welfare was his concern, something that modern economies let prosper apart from nature.
I find it difficult to understand that the cornucopians feel no regret for the changes I see taking place all around me (collapsing songbird populations; strange fish in the rivers; butterflies, birds and fish moving north; lakes that don’t freeze; suburbs marching over the hills); or consider matters like terrible agricultural and forestry practices, acidifying seas, tropical forests going up in smoke or melting glaciers nothing to worry about.
I think all these (and related) things will affect the human world. I think the cornucopians are out of their minds. But they are likely to be correct up about our ability to take care of the human world, right up to the very end.
Up to the edge of the cliff.
Last year (2010) was the wettest in the historical record and tied 2005 as the hottest. I think we are seeing the future now.
In 1980 Paul Ehrlich, a biologist (author of The Population Bomb), along with his colleagues the physicists John Harte and John Holdren, bet the economist Julian Simon on the future price of metals. Ehrlich bet the prices would increase as the better ores (those more accessible, with a higher metal content) were used up. Simon bet that metals would become cheaper and cheaper.
Simon won. In 1990 the prices of all five metals (copper, chromium, nickel, tin, tungsten) were lower.
While ores were poorer, processing methods became more efficient and the energy needed for processing got cheaper. The rise in metals prices (up to 1975) stimulated substitution of cheaper materials (as the use of plastic pipe instead of copper), which reduced demand for metals and kept their prices down (they had to compete).
Economics focuses on the human world. It teaches that the best use for resources is to exploit them as quickly as possible to economic extinction, then invest the profit in something else. As the resource becomes more scarce (and expensive) people will find alternatives and the human world will not suffer.
Malthusians point out that there is only so much of any resource (fresh water, ocean fish, fertile farmland, unpolluted air) and when they are gone what will we do. Some will be hard to substitute for.
Don’t worry, say the Malthusians—harvest the ocean for a tasty algal soup; adjust the climate to where we like it. If all else fails, we’re off to other worlds!
In the early nineteenth century Malthus’ concern was that population (which has the potential to grow geometrically) would always outgrow the supply of food (which grows slowly if at all). (The idea that animals produce far more young than can survive is one of the bases of evolution.) But at the time Malthus wrote the exploitation of fossil fuels was beginning. Fossil fuels let people build railroads to open up new farmland, ship food in steam powered steel ships all over the world, manufacture fertilizers, trawl distant seas. Over the next century and a half population grew by several times while world output (food and stuff) grew by several tens of times. Many more people became a lot more prosperous (even if some of them remain as poor as before). We could feed all those people a healthy diet even now, if food were fairly distributed.
So who’s right? Ehrlich? Simon? Both?
Simon refused to take a later bet Ehrlich proposed (his partner this time was the climatologist Stephen Schneider) in which Ehrlich focused on the resources themselves—the amount of fertile farmland per person, the extent of moist tropical forests, the global temperature, the number of species of plants and animals. Simon wouldn’t take the bet because he said that the degradation of the planet didn’t matter. Less farmland would be made up through fertilizer, or by producing food in other ways. The human habitat (the virtual world maintained by fossil fuels) would continue to improve. He used the analogy of the Olympics. While Ehrlich was betting the track would be worse, Simon was betting the times of the athletes would be better.
John Tierney, a journalist who writes a contrarian column in the Science Times of The New York Times recently described a bet with an oil expert, Matthew Simmons. In 2005 Simmons bet Tierney and his partner Rita Simon, Julian Simon’s widow, $5000 that the price of oil would average $200 or more in 2005 dollars in 2010. The price of oil rose to $145 by the summer of 2008 but fell with the global recession in the fall of 2008 to $50. The average price in 2010 was about $80. So again the cornucopians won (this time by chance).
Human affairs, like changes in climate, are unpredictable. I would bet Tierney that the level of carbon dioxide in the atmosphere in October 2015 measured from the Mauna Loa Observatory in Hawaii will be 398 ppmv or greater; that is, that carbon dioxide will continue to rise at 2 ppmv per year. Tierney, like Bjorn Lomborg, the skeptical environmentalist, thinks the effect of manmade carbon dioxide on climate will be minimal. (I could bet that one year between 2011 and 2015 will be either warmer or wetter, or both, than any since reliable measurements started in the 1880s.) Simon wouldn’t have taken my bet, because he wouldn’t have thought climatic conditions a matter of his concern. Human welfare was his concern, something that modern economies let prosper apart from nature.
I find it difficult to understand that the cornucopians feel no regret for the changes I see taking place all around me (collapsing songbird populations; strange fish in the rivers; butterflies, birds and fish moving north; lakes that don’t freeze; suburbs marching over the hills); or consider matters like terrible agricultural and forestry practices, acidifying seas, tropical forests going up in smoke or melting glaciers nothing to worry about.
I think all these (and related) things will affect the human world. I think the cornucopians are out of their minds. But they are likely to be correct up about our ability to take care of the human world, right up to the very end.
Up to the edge of the cliff.
Last year (2010) was the wettest in the historical record and tied 2005 as the hottest. I think we are seeing the future now.
Sunday, October 31, 2010
Wildflower Portraits
Bloodroot (Sanguinaria canadensis)
A childhood book, Two Little Savages, pointed out the blue hepatica as the first woodland wild flower of spring. Hepaticas hide their heads among their three lobed leaves and only open their starry blue or pink blooms when they’re ready. The more eager bloodroots seem to open all at once, ten days of joyful white blossoms at the edge of the garden and scattered throughout the meadow. Their fat reddish roots (that bleed when cut) choke out other plants, but not all: dutchman’s breeches send up their lacy leaves and stems of nodding pantaloons from tiny bulbs that sit below the roots of the larger plant a few weeks later. Bloodroot grows along the river and some lowland streams in our area. Like false hellbore (which outcompetes it), it favors pockets of rich soil. I moved a single clump from the riverbank to my garden forty years ago and now it grows throughout my garden and much of my meadow, especially where the grass is thinner. So it does well enough in our uplands away from water though I have never seen it in the wild there. Perhaps it hasn’t reached more distant areas in its post glacial travels or perhaps clearing and cattle grazing on the uplands in the nineteenth century led to its retreat to the center of its distribution.
Bloodroot sets lots of seed in plump scimitar shaped pods that poke up under its leaves in June. The seeds must germinate well: ants or birds have spread the plant all over my garden and meadow. I usually however reproduce bloodroot by root division, which is simpler than from seed. The naked reddish rhizomes lie just under the ground. A clump is easily lifted to pot or put elsewhere in the garden. You must do this if the bloodroots are encroaching on your yellow lady’s slippers or trilliums. (Even some hostas are vulnerable.) Bloodroots do well in sun or shade in any garden soil. Their leaves start to look messy in July, when you may cut them off.
A childhood book, Two Little Savages, pointed out the blue hepatica as the first woodland wild flower of spring. Hepaticas hide their heads among their three lobed leaves and only open their starry blue or pink blooms when they’re ready. The more eager bloodroots seem to open all at once, ten days of joyful white blossoms at the edge of the garden and scattered throughout the meadow. Their fat reddish roots (that bleed when cut) choke out other plants, but not all: dutchman’s breeches send up their lacy leaves and stems of nodding pantaloons from tiny bulbs that sit below the roots of the larger plant a few weeks later. Bloodroot grows along the river and some lowland streams in our area. Like false hellbore (which outcompetes it), it favors pockets of rich soil. I moved a single clump from the riverbank to my garden forty years ago and now it grows throughout my garden and much of my meadow, especially where the grass is thinner. So it does well enough in our uplands away from water though I have never seen it in the wild there. Perhaps it hasn’t reached more distant areas in its post glacial travels or perhaps clearing and cattle grazing on the uplands in the nineteenth century led to its retreat to the center of its distribution.
Bloodroot sets lots of seed in plump scimitar shaped pods that poke up under its leaves in June. The seeds must germinate well: ants or birds have spread the plant all over my garden and meadow. I usually however reproduce bloodroot by root division, which is simpler than from seed. The naked reddish rhizomes lie just under the ground. A clump is easily lifted to pot or put elsewhere in the garden. You must do this if the bloodroots are encroaching on your yellow lady’s slippers or trilliums. (Even some hostas are vulnerable.) Bloodroots do well in sun or shade in any garden soil. Their leaves start to look messy in July, when you may cut them off.
Monday, August 23, 2010
Biology Comics
Aliens
My immigrant friend gets defensive when I brake and start pulling up purple loosestrife from the roadside. Another dastardly invasive, I say! What’s wrong with it, he says? It’s pretty!
We’re the invasives of course. Even the Indians only came here 10,000-30,000 years ago, some walking across the Bering Strait with their wary companions the moose and buffalo, others following the fish and manatees of the kelp beds around the coasts of Siberia and Alaska in skin boats. For them it was a new world too, with tame mammoths on the steppe, giant sloths lumbering across the Great Plains, a fruit eating rhinocerous in the forests of Central America.
Hunters and gatherers tend to live in the natural world, though they change it. Agricultural people have been taking apart ecosystems for the last 10,000 years. Industrial people have been creating entirely new worlds for 200.
Vertebrates (except herbivores) access much of the energy in sunlight through insects, which have more protein then beef. Herbivores eat plants (transformed sunlight) directly.
Frogs eat mosquitoes, songbirds caterpillars, falcons dragonflies, many birds beetles, the Everglade Kite snails (an invertebrate, not an insect). Mice eat insects, invertebrates and plants and are eaten by foxes, coyotes, hawks, owls, weasels and men. (Mouse skeletons have been found in fossilized human dung.)
Green plants, the terrestrial transformers of sunlight (let’s ignore the bacteria and archaea), engage in chemical warfare with each other and with the insects that graze on them. (Maybe 20% of the leaf mass of a forest tree is lost to leaf eating insects in a summer.)
The trees and other plants defend themselves by producing so called secondary metabolites (those chemicals not involved in their primary metabolism, that of converting sunlight and carbon dioxide to carbohydrate). These glycosides, phenols, terpenes and alkaloids affect the taste, digestibility and toxicity of plant leaves (and other parts). A caterpillar biting into an aspen leaf begins the production of tannins that will in hours make the leaf indigestible to it. The release of secondary metabolites into the air warns nearby trees of an insect infestation; they also begin producing defensive chemicals.
The insects evolve methods of detoxifying what the trees produce. Some make use of the toxins: thus monarch caterpillars store the glycosides produced by milkweed; the bitter taste of the butterfly keeps the birds from eating it: chemical warfare carried to the next generation.
Insects and plants thus coevolve, for tens of thousands or tens of millions of years. Perhaps 90% of herbivorous insects are thought to be specialists on a few species of plants, which they have evolved the capacity to eat (detoxifying their secondary metabolites). The rest are generalists, that take their chances.
New plants (say, asian rhododendrons in eastern North America) have chemical defenses to which the local insects are not adapted. The new plant thus has an advantage over the natives. New insects, diseases (meeting organisms without immunity), fungi, predators (meeting defenseless populations) and parasites may have similar advantages. The European genotype of Phragmites (giant reed) is eaten by 5 species of insects in the northeastern U.S. and by 170 in Europe, with the result that it is replacing the native strain of Phragmites (eaten by numerous native insects) here. The plants are the same species (they can interbreed) but have different chemical defenses (and their inedible offspring will be selected for).
Over 400 arthropods (insects and spiders) eat the Melaleuca tree in Australia, where it is rare, but 8 eat it in Florida, where it is far too common. (Over time, native insects will learn to eat Melaleuca and also the European Phragmites; but the time may be long.)
Europeans had a similar effect on their own species in the New World, as they brought with them the crowd diseases of the Eurasian agriculturalists to which the native peoples of the Americas had no immunity. So, in seventeenth century opinion, “the good hand of God” cleared the New World of its native peoples. (Europeans suffered a similar fate in Africa, where people and disease had been evolving together longest; approximately half the Europeans emigrating to West Africa died of disease in a year.)
Anyway, the point is that native plants are more edible to native insects and so produce up to 4 times the insect biomass of nonnative plants, and 35 times more caterpillars (a primary food of songbirds). They support a far greater biomass of insect eaters above them.
So I pull the (inedible) purple loosestrife out of the swamp.
Not all native species are equal. A hundred years ago the chestnut was the primary nut producer in the eastern forest (its production dwarfing that of the oaks and hickories). Its mast supported turkeys, deer, mice, squirrels, bears, decomposers, buffalo and people, and the caterpillars that fed on its tasty leaves supported huge populations of songbirds. The chestnut was killed by an imported fungus and its place (partly) taken by the tulip tree (a native), which supports little wildlife.
How to construct an ecosystem?
The problem is breaking ecosystems apart. In intact ecosystems aliens may establish a niche but are less likely become invasive. Their flowers and fruit may be used by the natives, even if their leaves are inedible. (In 10,000 years the leaves will become edible.)
Against some introductions— some predators, fungi, bacteria, insects, parasites, amphibians—there is no defense. For some time, as ships and planes spread plants and animals around, the world will become poorer (until, say, elms develop resistance to Dutch elm disease, American toads to chytrid fungus, chestnuts to chestnut blight).
As the abundant world fades, few will remember it.
Eventually a new world will blossom.
My immigrant friend gets defensive when I brake and start pulling up purple loosestrife from the roadside. Another dastardly invasive, I say! What’s wrong with it, he says? It’s pretty!
We’re the invasives of course. Even the Indians only came here 10,000-30,000 years ago, some walking across the Bering Strait with their wary companions the moose and buffalo, others following the fish and manatees of the kelp beds around the coasts of Siberia and Alaska in skin boats. For them it was a new world too, with tame mammoths on the steppe, giant sloths lumbering across the Great Plains, a fruit eating rhinocerous in the forests of Central America.
Hunters and gatherers tend to live in the natural world, though they change it. Agricultural people have been taking apart ecosystems for the last 10,000 years. Industrial people have been creating entirely new worlds for 200.
Vertebrates (except herbivores) access much of the energy in sunlight through insects, which have more protein then beef. Herbivores eat plants (transformed sunlight) directly.
Frogs eat mosquitoes, songbirds caterpillars, falcons dragonflies, many birds beetles, the Everglade Kite snails (an invertebrate, not an insect). Mice eat insects, invertebrates and plants and are eaten by foxes, coyotes, hawks, owls, weasels and men. (Mouse skeletons have been found in fossilized human dung.)
Green plants, the terrestrial transformers of sunlight (let’s ignore the bacteria and archaea), engage in chemical warfare with each other and with the insects that graze on them. (Maybe 20% of the leaf mass of a forest tree is lost to leaf eating insects in a summer.)
The trees and other plants defend themselves by producing so called secondary metabolites (those chemicals not involved in their primary metabolism, that of converting sunlight and carbon dioxide to carbohydrate). These glycosides, phenols, terpenes and alkaloids affect the taste, digestibility and toxicity of plant leaves (and other parts). A caterpillar biting into an aspen leaf begins the production of tannins that will in hours make the leaf indigestible to it. The release of secondary metabolites into the air warns nearby trees of an insect infestation; they also begin producing defensive chemicals.
The insects evolve methods of detoxifying what the trees produce. Some make use of the toxins: thus monarch caterpillars store the glycosides produced by milkweed; the bitter taste of the butterfly keeps the birds from eating it: chemical warfare carried to the next generation.
Insects and plants thus coevolve, for tens of thousands or tens of millions of years. Perhaps 90% of herbivorous insects are thought to be specialists on a few species of plants, which they have evolved the capacity to eat (detoxifying their secondary metabolites). The rest are generalists, that take their chances.
New plants (say, asian rhododendrons in eastern North America) have chemical defenses to which the local insects are not adapted. The new plant thus has an advantage over the natives. New insects, diseases (meeting organisms without immunity), fungi, predators (meeting defenseless populations) and parasites may have similar advantages. The European genotype of Phragmites (giant reed) is eaten by 5 species of insects in the northeastern U.S. and by 170 in Europe, with the result that it is replacing the native strain of Phragmites (eaten by numerous native insects) here. The plants are the same species (they can interbreed) but have different chemical defenses (and their inedible offspring will be selected for).
Over 400 arthropods (insects and spiders) eat the Melaleuca tree in Australia, where it is rare, but 8 eat it in Florida, where it is far too common. (Over time, native insects will learn to eat Melaleuca and also the European Phragmites; but the time may be long.)
Europeans had a similar effect on their own species in the New World, as they brought with them the crowd diseases of the Eurasian agriculturalists to which the native peoples of the Americas had no immunity. So, in seventeenth century opinion, “the good hand of God” cleared the New World of its native peoples. (Europeans suffered a similar fate in Africa, where people and disease had been evolving together longest; approximately half the Europeans emigrating to West Africa died of disease in a year.)
Anyway, the point is that native plants are more edible to native insects and so produce up to 4 times the insect biomass of nonnative plants, and 35 times more caterpillars (a primary food of songbirds). They support a far greater biomass of insect eaters above them.
So I pull the (inedible) purple loosestrife out of the swamp.
Not all native species are equal. A hundred years ago the chestnut was the primary nut producer in the eastern forest (its production dwarfing that of the oaks and hickories). Its mast supported turkeys, deer, mice, squirrels, bears, decomposers, buffalo and people, and the caterpillars that fed on its tasty leaves supported huge populations of songbirds. The chestnut was killed by an imported fungus and its place (partly) taken by the tulip tree (a native), which supports little wildlife.
How to construct an ecosystem?
The problem is breaking ecosystems apart. In intact ecosystems aliens may establish a niche but are less likely become invasive. Their flowers and fruit may be used by the natives, even if their leaves are inedible. (In 10,000 years the leaves will become edible.)
Against some introductions— some predators, fungi, bacteria, insects, parasites, amphibians—there is no defense. For some time, as ships and planes spread plants and animals around, the world will become poorer (until, say, elms develop resistance to Dutch elm disease, American toads to chytrid fungus, chestnuts to chestnut blight).
As the abundant world fades, few will remember it.
Eventually a new world will blossom.
Friday, August 6, 2010
Biology Comics
Biochar and Silicate Rocks
Heavy rains are increasing, Arctic ice is melting, Russian peat bogs are burning, methane is bubbling out of the East Siberian Sea, the summer’s heat and humidity grows and grows. Alone each means nothing, together they add up to a changing climate, which only demagogs and idiots ignore.
Of course it may all turn around and (especially here in the U.S. northeast) turn cold for the next 1000 years. We are poking the climate beast, with unpredictable results, as Wallace Broecker remarks.
The problem is too much carbon dioxide (and other heat trapping gases, such as methane, nitrous oxide and the chlorofluorocarbons) in the atmosphere. And too much soot and black carbon in the air and falling out on Arctic ice.
We’re putting the gases (and the soot and dust) there. Since modern life runs on fossil fuels, we aren’t likely to stop; or stop fast enough. Is anyone going to make China stop? Or India? Or the U.S. for that matter?
Saving energy is boring, nuclear power risky, wind and solar are expensive and require storage schemes (pumped water reservoirs, chemical batteries) that are expensive, destructive or dangerous. Forget about sequestering carbon from smokestacks, it’s too complicated, it takes too much energy, it’s a pipe dream. What free lunch?
So what about continuing to dig up coal and geoengineer the planet? Launch tiny mirrors into the atmosphere to reflect sunlight back to space. (Of course the ocean and atmosphere would continue to acidify.) Spray sulfur dioxide from planes into the stratosphere to reflect sunlight, or hey!—just remove the controls on sulfur from fossil fuels. Or spray seawater into the atmosphere to increase the reflectivity of clouds. Or pump seawater onto Arctic ice to thicken it. (Why not, to the last two.)
Lime the planet to counter acid rain!
The main downside of schemes to reduce incoming sunlight is that the planet will continue to acidify. As for spraying sulfur dioxide, the sulfur dioxide will eventually fall out on the land and ocean. There are probably other downsides—changes in rainfall or airflow, changes in stratospheric chemistry or the growth rate of plants. To think all such effects are predictable is nonsense.
So what about taking carbon dioxide directly from the air. One idea is to fertilize the oceans with urea (a nitrogen fertilizer), or finely ground iron (a limiting nutrient in the sea), or by installing huge pipes to increase the transfer of nutrients from deep water (where they are common) to the sunlit surface (where they fuel algal growth). The fertilized algae on the surface divide and grow, are eaten by fish (or die), and sink as tiny corpses or fish poop to the bottom of the ocean where the carbon (taken by the algae from the air) is locked up for thousands of years. Unfortunately, fertilization schemes don’t seem to work (the carbon stored is negligible compared to the effort put into fertilization). Their other effects on the sea are also unknown.
On the other hand, our overfishing of the oceans (a natural result of unregulated capitalistic effort) is reducing them to ecosystems of algae and jellyfish, while our heavy fertilization of large continental watersheds, with the resulting dead zones of maximized algal growth at the mouths of major rivers, may be storing more carbon than we realize. (The oil in farm fertilizer producing more oil in sediments.) Of course destroying the oceans to save the planet is nuts.
What to do? Well all that boring stuff (fast breeder reactors, reducing population, cars that get 200 miles to the gallon, insulating houses, reducing poverty, empowering poor women—both the last tend to reduce population growth) helps. Reforesting or revegetating degraded lands stores carbon in soils, plants and trees. Reducing numbers of cattle and sheep on overgrazed lands (say in the U.S. Great Basin and High Plains) lets shrubs and perennial grasses store carbon in soils. So does rotational grazing of dairy cattle on eastern or midwestern pastures. Proper management of croplands lets them store some carbon (or lose less). Some writers claim the soils’ carbon stores are full after 15-30 years, but soil storage capacity undoubtedly varies with the site.
Reforesting degraded lands lets trees store carbon in their tissues and in the soil. Billions of acres of degraded lands are candidates for reforestation: much of the Mediterranean basin, including the mountainous islands; much of China; the Tibetan plateau; the Andean altiplano (both were deforested by people thousands of years ago for their crops and animals); the Himalayan foothills; much of the U.S. Southeast and Midwest; some deserts.
In the Sahel in the 1970s, millet farmers let acacia trees grow in their fields. This was a folk technique that had been mocked by modern agronomists. The trees provided forage for the animals, which meant more manure for the crops. More trees grew, sprouting in the dung of the (more numerous) grazing animals. This let the farmers raise more animals, which meant more dung and more cropland. Eventually several million acres of the Sahel were reclaimed for agriculture. The trees store carbon in the soil and have slightly increased rainfall over the northern Sahel.
The huarango tree of the Atacama Desert in Peru (one of the driest places in the world) captures water from ocean mists. Its roots draw up water from 150 feet down. It breaks the wind over the desert and, by condensing mists, moistens (slightly) the upper layers of the soil. It lives a millennium and (a mesquite) produces a sweet edible pod, which can be used for fodder, ground into flour, or made into a syrup or beer. Its fragrant blossoms support bees. The Nazca of 1500 years ago cut down huarangos to plant irrigated cotton and corn in the river valleys, exposing the desert to floods and wind erosion. Modern residents of the Atacama cut the trees for firewood. The tree is thorny, not particularly attractive, and invasive where successful and could support a life based on carbon storage, goats, honey and beer.
Agricultural revegetation of degraded lands (acacia trees, camels and millet; salicornia, a forage crop irrigable with seawater; huarango trees; jojoba, a shrub with oil bearing seeds; grapevines; mangoes; pomegranates; other fruit and nut trees) lets carbon accumulate in soils. If the prunings from the trees and the crop wastes are converted to charcoal (biochar) and spread on farmland (where the char promotes plant growth) their carbon will be stored for tens of thousands of years. (Perhaps 50,000 years: this will work in industrial agriculture; with poor peasant farmers, the charcoal will be used for cooking.)
Turning the crop residues of industrial agriculture into biochar would store billions of tons of carbon a year. Estimates range from 1-2 billion tons a year. (We release 8-9 billion tons of carbon as carbon dioxide a year to the atmosphere.) The equipment to turn corn stalks or wheat straw into charcoal is cheap, the process simple. Since biochar makes an excellent fertilizer, and reduces fertilizer runoff, the equipment would pay for itself in a year or two.
Revegetated forestlands store carbon in the trees and in the soil. The carbon in the trees is released to the atmosphere when the trees are cut (most processed trees return as carbon to the atmosphere in ten years); or when they die and decay. While growing, the forests continue to store carbon (say, for 300-2000 years). When storage slows, the best way to cut the trees is selectively, so as to expose the soil as little as possible to sunlight, which speeds up its losses of carbon. The best bottom log could be used as sawn lumber (a carbon loss, factored into any payments for carbon storage; but the trunk represents only a fraction of the tree’s mass) and the rest converted to biochar and spread back on the forest; or sold to spread on farmland. If landowners are to be paid for storing carbon, the way to maximize a forest’s carbon storage would have to be worked out; and calculated by the year or decade. We have 300 years to do that. Any payments for carbon storage should be based on real numbers, not guesses. Payments from, say, a tax on fossil fuels.
Changing agricultural practices to capture carbon; revegetating degraded lands; producing biochar involve no downsides of which I am aware. Such practices would produce a return on investment and improve the nutrient storage capacity of watersheds, and thus improve the health of riverine and ocean fisheries. We might store a quarter of the carbon dioxide we currently produce by such methods, perhaps more.
One other technique offers carbon storage, but with a limited downside. This involves capturing carbon dioxide through its natural (exothermic) reaction with magnesium oxide or calcium oxide rocks. The reaction forms stable carbonates (limestones). One can foster this reaction by mining and grinding the rocks and spreading them on land or on the sea. The energy involved in the mining and pulverizing is inconsequential in comparison with the carbon stored. Spreading the powder on the ocean (especially over the productive continental shelves) lets one reduce the acidification of the sea as well as capture carbon dioxide from the air. (A free lunch?) One picks cliffs of the appropriate rocks on a seacoast (volcanic rocks are good), sets up a mine and sends the powder down to slow moving ships that spread it over the sea. (Schemes like this have been suggested for the Scottish coast to produce builders gravel.)
In biologically appropriate situations, the mine could be made into a pit for pumped storage of seawater (another munch at lunch). This isn’t appropriate where marine life would be harmed, thus not, say, on the Palisade escarpment north of New York City, above the Hudson estuary, where the rock is appropriate and the pumped storage capacity could use the photovoltaic output of the city, but the damage to the estuary would likely be great.
The variability of solar power means it has to be backed up. The power supply for a modern grid cannot be interrupted or the system will crash. Since the output from the sun and wind is unpredictable, one must either invest in double the capacity—the fossil or nuclear fuelled grid as well as the unreliable photovoltaic or wind capacity— or have some storage that can be switched on when the solar supply falters. Flywheels; chemical batteries; compressed air in abandoned mines; pumped storage all work. Pumped water from the sea is a natural (say, on Oahu in Hawaii; in the Canaries; in California or Maine; in Scotland). A pumped storage scheme was suggested for Storm King Mountain on the Hudson in the late sixties but was abandoned after an outcry from environmentalists (me included). The high dams on the ruined rivers of the U.S. west (the Colorado, the Yellowstone, the Columbia) offer obvious sites for pumped storage: all they lack are the pumps and a safe way (for the riverine biota) to pump sufficient volumes of water back up behind the dams. (A nonbiologically invasive way to extract water from rivers would make many things better.)
Of course, the ultimate solution to climate change is fewer people, saving energy, fast breeder reactors, the electrification of transport and the energy supply (so all energy can be provided by the sun). Alleviating poverty and empowering women, the projects of the “skeptical environmentalist,” a foolish and publicity hungry Dane, will also reduce population.
Let’s do it all! Make biochar, mine silicate rocks, have one child, and plant trees.
Heavy rains are increasing, Arctic ice is melting, Russian peat bogs are burning, methane is bubbling out of the East Siberian Sea, the summer’s heat and humidity grows and grows. Alone each means nothing, together they add up to a changing climate, which only demagogs and idiots ignore.
Of course it may all turn around and (especially here in the U.S. northeast) turn cold for the next 1000 years. We are poking the climate beast, with unpredictable results, as Wallace Broecker remarks.
The problem is too much carbon dioxide (and other heat trapping gases, such as methane, nitrous oxide and the chlorofluorocarbons) in the atmosphere. And too much soot and black carbon in the air and falling out on Arctic ice.
We’re putting the gases (and the soot and dust) there. Since modern life runs on fossil fuels, we aren’t likely to stop; or stop fast enough. Is anyone going to make China stop? Or India? Or the U.S. for that matter?
Saving energy is boring, nuclear power risky, wind and solar are expensive and require storage schemes (pumped water reservoirs, chemical batteries) that are expensive, destructive or dangerous. Forget about sequestering carbon from smokestacks, it’s too complicated, it takes too much energy, it’s a pipe dream. What free lunch?
So what about continuing to dig up coal and geoengineer the planet? Launch tiny mirrors into the atmosphere to reflect sunlight back to space. (Of course the ocean and atmosphere would continue to acidify.) Spray sulfur dioxide from planes into the stratosphere to reflect sunlight, or hey!—just remove the controls on sulfur from fossil fuels. Or spray seawater into the atmosphere to increase the reflectivity of clouds. Or pump seawater onto Arctic ice to thicken it. (Why not, to the last two.)
Lime the planet to counter acid rain!
The main downside of schemes to reduce incoming sunlight is that the planet will continue to acidify. As for spraying sulfur dioxide, the sulfur dioxide will eventually fall out on the land and ocean. There are probably other downsides—changes in rainfall or airflow, changes in stratospheric chemistry or the growth rate of plants. To think all such effects are predictable is nonsense.
So what about taking carbon dioxide directly from the air. One idea is to fertilize the oceans with urea (a nitrogen fertilizer), or finely ground iron (a limiting nutrient in the sea), or by installing huge pipes to increase the transfer of nutrients from deep water (where they are common) to the sunlit surface (where they fuel algal growth). The fertilized algae on the surface divide and grow, are eaten by fish (or die), and sink as tiny corpses or fish poop to the bottom of the ocean where the carbon (taken by the algae from the air) is locked up for thousands of years. Unfortunately, fertilization schemes don’t seem to work (the carbon stored is negligible compared to the effort put into fertilization). Their other effects on the sea are also unknown.
On the other hand, our overfishing of the oceans (a natural result of unregulated capitalistic effort) is reducing them to ecosystems of algae and jellyfish, while our heavy fertilization of large continental watersheds, with the resulting dead zones of maximized algal growth at the mouths of major rivers, may be storing more carbon than we realize. (The oil in farm fertilizer producing more oil in sediments.) Of course destroying the oceans to save the planet is nuts.
What to do? Well all that boring stuff (fast breeder reactors, reducing population, cars that get 200 miles to the gallon, insulating houses, reducing poverty, empowering poor women—both the last tend to reduce population growth) helps. Reforesting or revegetating degraded lands stores carbon in soils, plants and trees. Reducing numbers of cattle and sheep on overgrazed lands (say in the U.S. Great Basin and High Plains) lets shrubs and perennial grasses store carbon in soils. So does rotational grazing of dairy cattle on eastern or midwestern pastures. Proper management of croplands lets them store some carbon (or lose less). Some writers claim the soils’ carbon stores are full after 15-30 years, but soil storage capacity undoubtedly varies with the site.
Reforesting degraded lands lets trees store carbon in their tissues and in the soil. Billions of acres of degraded lands are candidates for reforestation: much of the Mediterranean basin, including the mountainous islands; much of China; the Tibetan plateau; the Andean altiplano (both were deforested by people thousands of years ago for their crops and animals); the Himalayan foothills; much of the U.S. Southeast and Midwest; some deserts.
In the Sahel in the 1970s, millet farmers let acacia trees grow in their fields. This was a folk technique that had been mocked by modern agronomists. The trees provided forage for the animals, which meant more manure for the crops. More trees grew, sprouting in the dung of the (more numerous) grazing animals. This let the farmers raise more animals, which meant more dung and more cropland. Eventually several million acres of the Sahel were reclaimed for agriculture. The trees store carbon in the soil and have slightly increased rainfall over the northern Sahel.
The huarango tree of the Atacama Desert in Peru (one of the driest places in the world) captures water from ocean mists. Its roots draw up water from 150 feet down. It breaks the wind over the desert and, by condensing mists, moistens (slightly) the upper layers of the soil. It lives a millennium and (a mesquite) produces a sweet edible pod, which can be used for fodder, ground into flour, or made into a syrup or beer. Its fragrant blossoms support bees. The Nazca of 1500 years ago cut down huarangos to plant irrigated cotton and corn in the river valleys, exposing the desert to floods and wind erosion. Modern residents of the Atacama cut the trees for firewood. The tree is thorny, not particularly attractive, and invasive where successful and could support a life based on carbon storage, goats, honey and beer.
Agricultural revegetation of degraded lands (acacia trees, camels and millet; salicornia, a forage crop irrigable with seawater; huarango trees; jojoba, a shrub with oil bearing seeds; grapevines; mangoes; pomegranates; other fruit and nut trees) lets carbon accumulate in soils. If the prunings from the trees and the crop wastes are converted to charcoal (biochar) and spread on farmland (where the char promotes plant growth) their carbon will be stored for tens of thousands of years. (Perhaps 50,000 years: this will work in industrial agriculture; with poor peasant farmers, the charcoal will be used for cooking.)
Turning the crop residues of industrial agriculture into biochar would store billions of tons of carbon a year. Estimates range from 1-2 billion tons a year. (We release 8-9 billion tons of carbon as carbon dioxide a year to the atmosphere.) The equipment to turn corn stalks or wheat straw into charcoal is cheap, the process simple. Since biochar makes an excellent fertilizer, and reduces fertilizer runoff, the equipment would pay for itself in a year or two.
Revegetated forestlands store carbon in the trees and in the soil. The carbon in the trees is released to the atmosphere when the trees are cut (most processed trees return as carbon to the atmosphere in ten years); or when they die and decay. While growing, the forests continue to store carbon (say, for 300-2000 years). When storage slows, the best way to cut the trees is selectively, so as to expose the soil as little as possible to sunlight, which speeds up its losses of carbon. The best bottom log could be used as sawn lumber (a carbon loss, factored into any payments for carbon storage; but the trunk represents only a fraction of the tree’s mass) and the rest converted to biochar and spread back on the forest; or sold to spread on farmland. If landowners are to be paid for storing carbon, the way to maximize a forest’s carbon storage would have to be worked out; and calculated by the year or decade. We have 300 years to do that. Any payments for carbon storage should be based on real numbers, not guesses. Payments from, say, a tax on fossil fuels.
Changing agricultural practices to capture carbon; revegetating degraded lands; producing biochar involve no downsides of which I am aware. Such practices would produce a return on investment and improve the nutrient storage capacity of watersheds, and thus improve the health of riverine and ocean fisheries. We might store a quarter of the carbon dioxide we currently produce by such methods, perhaps more.
One other technique offers carbon storage, but with a limited downside. This involves capturing carbon dioxide through its natural (exothermic) reaction with magnesium oxide or calcium oxide rocks. The reaction forms stable carbonates (limestones). One can foster this reaction by mining and grinding the rocks and spreading them on land or on the sea. The energy involved in the mining and pulverizing is inconsequential in comparison with the carbon stored. Spreading the powder on the ocean (especially over the productive continental shelves) lets one reduce the acidification of the sea as well as capture carbon dioxide from the air. (A free lunch?) One picks cliffs of the appropriate rocks on a seacoast (volcanic rocks are good), sets up a mine and sends the powder down to slow moving ships that spread it over the sea. (Schemes like this have been suggested for the Scottish coast to produce builders gravel.)
In biologically appropriate situations, the mine could be made into a pit for pumped storage of seawater (another munch at lunch). This isn’t appropriate where marine life would be harmed, thus not, say, on the Palisade escarpment north of New York City, above the Hudson estuary, where the rock is appropriate and the pumped storage capacity could use the photovoltaic output of the city, but the damage to the estuary would likely be great.
The variability of solar power means it has to be backed up. The power supply for a modern grid cannot be interrupted or the system will crash. Since the output from the sun and wind is unpredictable, one must either invest in double the capacity—the fossil or nuclear fuelled grid as well as the unreliable photovoltaic or wind capacity— or have some storage that can be switched on when the solar supply falters. Flywheels; chemical batteries; compressed air in abandoned mines; pumped storage all work. Pumped water from the sea is a natural (say, on Oahu in Hawaii; in the Canaries; in California or Maine; in Scotland). A pumped storage scheme was suggested for Storm King Mountain on the Hudson in the late sixties but was abandoned after an outcry from environmentalists (me included). The high dams on the ruined rivers of the U.S. west (the Colorado, the Yellowstone, the Columbia) offer obvious sites for pumped storage: all they lack are the pumps and a safe way (for the riverine biota) to pump sufficient volumes of water back up behind the dams. (A nonbiologically invasive way to extract water from rivers would make many things better.)
Of course, the ultimate solution to climate change is fewer people, saving energy, fast breeder reactors, the electrification of transport and the energy supply (so all energy can be provided by the sun). Alleviating poverty and empowering women, the projects of the “skeptical environmentalist,” a foolish and publicity hungry Dane, will also reduce population.
Let’s do it all! Make biochar, mine silicate rocks, have one child, and plant trees.
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