Creating an Ecological Society. Chris Williams

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Название Creating an Ecological Society
Автор произведения Chris Williams
Жанр Биология
Серия
Издательство Биология
Год выпуска 0
isbn 9781583676318



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described the magnitude of fossil fuel consumption in other terms: “For the first time in Earth’s history, a single species is responsible for the entropic degradation of the biosphere by releasing more energy through transformation than is being replaced by global photosynthesis.”23

      As increased atmospheric CO2 drives increasing temperature, feedback loops occur. Permafrost soils that have been frozen for millennia, comprising almost a quarter of the land of the Northern Hemisphere, are beginning to melt. They hold a huge amount of carbon, stored as both organic matter and as methane gas (CH4). As these soils warm and thaw, they release large quantities of greenhouse gases—CO2 from decomposing organic matter and methane—leading to even more global warming. It is estimated that this feedback loop may result in up to 15 percent of the carbon stored in permafrost ending up in the atmosphere by the end of the century.24

      This massive amount of fossil fuel combustion is one of the major interventions made in the carbon cycle. Instead of a relatively stable amount of atmospheric carbon cycling from the atmosphere to plants, soils, and animals and then returning to the atmosphere, which existed for centuries, ever-greater amounts of CO2 accumulate in the atmosphere and the oceans. The results are the warming planet and acidification of the seas. The warming of the atmosphere, in turn, has led to drastic changes in climate and to much suffering.

       Remedial Solutions

      To date, attempts to counteract or reduce human-induced alterations to the carbon cycle and resulting climate change have all proved inadequate. These “solutions” don’t go far enough either because there has been no desire to disturb corporate profits or they offer new possibilities to profit through market-based approaches that can lead to further problems. A number of more desperate and even more destabilizing proposals have been made for large-scale geoengineering, such as shooting sulfate particles into the atmosphere to reflect a portion of incoming light from the sun, thereby lessening warming of Earth.

      While biofuels are regarded by some as a significant part of the solution, their impacts are mostly negative: on people, land, water, and biodiversity. Many problems are the result from the many side effects of capitalist agricultural production in general, such as environmental contamination with pesticides and with synthetic fertilizers, but need to be considered as outcomes when growing crops for biofuel production. Additionally, land that could have been used to grow food for people is used to grow fuel for cars: some 40 percent of the U.S. corn crop is used to make ethanol fuel. In addition, the land grabs and deforestation that occurs in order to grow oil palm in order to make “biodiesel” has enormous adverse consequence for people, wildlife, and the atmosphere as we described earlier. Some biofuels take even more energy to produce than they yield. The extent of their impacts depends on the particular biofuel crop grown, production and processing of biofuel feedstocks, the scale of production, and how they influence land-use change as to who gets displaced. Finally, while using some types of biofuels might reduce CO2 emission to the atmosphere, others emit more CO2 than with fossil fuels. Thus, this supposed remedy for the negative effects of fossil fuels has so many harmful side effects that is no solution at all.25

      Some scientists advocate the expansion of nuclear power as the only way to effectively reduce emissions of carbon dioxide at the scale required. Aside from myriad safety problems with the operation of nuclear plants—and the high costs of electricity generation—a process for the safe disposal of nuclear waste, which remains radioactive for hundreds of thousands of years, is not yet known.

      One often-cited emerging technology, carbon capture and storage (CCS)—essentially capturing and permanently burying carbon dioxide below ground—is untried and untested at anything close to the scale needed to make a difference. Its advocacy promotes the idea that we can carry on burning fossil fuels because at some point we’ll be able to store the gaseous waste product. CO2 captured in the pilot CCS projects is mostly pumped underground in order to pump out more oil.26

      Even more fraudulently, individuals are encouraged to compensate the world for the carbon used in commercial airplane flights and other activities by purchasing so-called offset credits (see discussion later in this chapter on Putting a Price on Nature). There are a number of problems inherent in these schemes, especially a lack of accountability or oversight that encourages cheating and gaming of the system. A report by the Oakland Institute, an independent policy think tank, concluded that “there is mounting evidence that … corporate land acquisitions for climate change mitigation—including forestry plantations—severely compromise not only local ecologies but also the livelihoods of some of the world’s most vulnerable people living at subsistence level in rural areas in developing countries.”27

       ORGANIC MATTER FLOWS AND SOIL HEALTH

      The organic matter cycle is a key part of the carbon cycle—after all, the material of life is built out of chains and rings of carbon atoms, assembled by the photosynthetic activity of green plants. Organic materials are stored aboveground in living plants and animals and in much larger quantities in soils as both living organisms and the residues of dead ones. As discussed earlier, agricultural practices have led to a large loss in soil organic matter, contributing to increases in atmospheric CO2 levels. But because organic matter levels in soils have such profound effects on agriculture and the environment, it needs attention as a separate issue.

      Ample amounts of organic matter are of critical importance to maintaining healthy and productive soils. As soil organic matter content decreases, biodiversity decreases and disease organisms and nematodes that feed on crop plants proliferate because of the decreased competition with other organisms. In general, the simpler rotations of modern industrial-style farming make crop pests—weeds, soil-borne diseases, and insects—more problematic when the soils are depleted of organic matter.28 As organic matter decreases, soils become more compact and less water is able to infiltrate. Fewer nutrients are stored in soils and soil nutrients are more easily lost to leaching and erosion. Accelerated erosion causes a further loss of organic matter along with the lost topsoil. The loss of topsoil and organic matter creates a downward spiral of soil fertility. More aggregates break down and more erosion occurs. It’s a classic feedback loop: the original disturbance causes other changes that further magnify the first disruption. Drastic intervention with fertilizers, pesticides, extra irrigation, and equipment will temporarily remedy the situation—but at a great ecological, monetary, and social cost.

      Some early agricultural practices reduced soil organic matter, such as when wheat was grown on the hillsides of Greece, resulting in erosion of topsoil rich in organic matter and negative effects for long-term food production. But other cultures developed methods to help maintain soil fertility. The Mesoamericans developed the chinampa system in the Valley of Mexico: planting beds were built, using sediments rich in organic matter from shallow lakes.

      Disturbances in organic matter flows were recognized over a century ago. Three scientists examining the problem of “worn-out” soils in 1908 concluded that the “depletion of the soil humus [organic matter] supply is apt to be a fundamental cause of lowered crop yields.”29 Contemporary soil scientists have only recently rediscovered this reality.30

      Practices that developed and were made common during the industrialization of agriculture—such as inadequate crop rotations composed of relatively few commodity crops, reliance on nitrogen from commercial fertilizers instead of legumes, the concentration of large numbers of farm animals separated from the land that grows their feed, and intensive tillage that breaks up soil structure—have led to a great loss of soil organic matter. Agricultural soils in the United States have about half of the organic matter they contained before forests and grasslands were converted to agriculture.31 It is estimated that the world’s soils have lost between 50 and 70 percent of the organic matter they contained before they were farmed.32 Over 30 percent of the world’s soils are moderately or severely degraded.33

      Pesticides are routinely used to control organisms that limit crop growth. But more insecticides are needed because plants are more susceptible to insect attack when growing in soils depleted of organic matter and in fields and their surroundings that have low plant