Soil Disturbance Challenge for Doddridge County Watershed Association

The Earth’s Soil Serves as a Carbon Storehouse

Analysis by S. Tom Bond, Retired Chemistry Professor and Resident Farmer, Lewis County, WV

An exciting new way to reduce atmospheric carbon dioxide by a natural process is being discussed in many places. See here, and see here, and see here, and see here, for example.

To understand it, some background is needed. As the reader will know, most of our energy in this age is derived from burning carbon containing compounds (fossil fuels) in the form of natural gas, oil and coal. They are burned with oxygen in air and carbon dioxide is formed. Less energy is derived from the hydrogen in these compounds atom for atom, and most of the compounds formed from the sulfur, phosphorus. and other elements present in fuels are pollutants.

The process of burning (combustion) oxidizes carbon and the other elements, but some of the carbon dioxide and water from the air are converted to plant life by photosynthesis. Decomposition of dead plants and animals exposed to the air also contributes carbon dioxide. The evidence indicates this has been going on for 2.8 billion years. Sometimes in geological periods past there has been greater or lesser amounts of carbon dioxide in the atmosphere than now. The return to plant life of oxidized carbon through photosynthesis is slow.

Much of plant life grows roots into the soil. When the plant dies its roots are converted to a soil carbon form known as humus to gardeners. This is done by fungus, (actually up to 1.5 million species are present in the soil worldwide according to a recent article in Science, the journal of the AAAS) and other microorganisms. As everyone knows, humus helps hold nutrients in the soil, and water. This helps new plants to grow. Scientists now understand soil based life is an association between plants and special microorganisms acting between soil and plant roots. This helps the plants to get nutrients from the soil and from the soil carbon compounds (which are very numerous and complex) in humus.

The excitement is that in many parts of the world soil carbon is depleted, but with proper management it can be rebuilt. It is a huge reservoir – one source gives 2.7 x 10¹⁸ long tons of carbon in soil compared to 0.78 long tons in the atmosphere and 0.75 long tons in biomass, i.e., living matter.

According to Rattan Lal, director of Ohio State University’s Carbon Management and Sequestration Center, the world’s cultivated soils have lost between 50 and 70 percent of their original carbon stock, much of which has oxidized upon exposure to air. (Notice this is cultivated soils, not all soils.) Some of it goes back 15,000 years to when forests were first cleared for crops.

Regenerating these soils involves agricultural practices such as using year-around cover crops, and what is commonly called rotational pasture and other measures. Top priority would be in restoring degraded and eroded lands, avoiding both deforestation, and farming of peat land. Restoration of mangrove areas along coasts, salt marshes and sea grasses would also play a part.

The good thing about this method of reducing carbon dioxide, in contrast to mechanical sequestration, is that it increases the capacity to produce food for the coming increase in world population by increasing soil productivity, and making soils more resilient to both floods and drought. It is not high tech, but involves techniques already with an advanced state of understanding. It is not capital intensive, but education intensive.

One of the most severe problems is with grassland. Much of the world’s agricultural land produces grass and is not suitable for crops, except for certain small favored spots. It is too dry, too hilly, or too wet for crops which produce parts that can be eaten by humans. Grasslands developed under herds of grazing animals, so they are adapted to each other.

Here is a video of an expert, Allan Savory of Rhodesia (now Nyasaland) in Africa explaining the method in a TED talk. It will be recognized by any Appalachian farmer as “rotational grazing.” It is also called holistic management. The animals are kept close together, stay on one spot long enough to eat the top one-third or one-half the plant, the part that has the highest sugar content, then moved on. (The customary practice now is to keep animals in the same field continuously, in the worst case, as long as any of the plant growth remains there.)

The claims of holistic management have their detractors, too. But if you are “into” research on extreme hydrocarbon energy exploitation (shale drilling, mountaintop removal, deep water drilling, etc.) you have learned to look at who is financing what. Don’t skip the last line. Established environmental groups can be slow to change, too! They can’t argue that grazing doesn’t reduce grass fires, though, a benefit important near habitation.

Ohio State University maintains the Carbon Management and Sequestration Center, which lists four measures for reestablishment of soil carbon: afforestation, wetlands management, no-tillage of soils and close management of grazing. (1) Reforestation is the name that has been used for decades when the objective was to get the resulting timber. It is now recognized as a good way to build soil, too, because trees have the same kind of relations with microorganisms and humus as grass. Our Appalachian soils developed under forest cover. It is also recognized that the carbon in timber (since it is protected by roofs, etc., last decades to centuries after the tree is cut, before returning to carbon dioxide.

(2) Wetlands often preserve carbon for a long time, since the remains of plants are cut off from oxygen at the water level. Peat is a residue built up from wetland plants that is almost entirely organic. At one time it was cut and dried for fuel, a practice which has largely been discontinued. However peatlands can be drained and farmed, resulting in oxidation of the peat to carbon dioxide. The emphasis is now on preventing this from being done. (3) “No tillage” means not plowing to plant crops which have been traditionally handled this way. Plowing and tillage are primarily weed control activities. Today the best method for corn, soybeans and such like is to plant a cover crop, frequently a legume, which gets good growth before winter and keeps the ground covered and crowds out baby weeds. This prevents oxidation of the carbon in the soil, adds to it, and helps fertilize the main crop. It also helps control some insect pests and encourages wildlife.

So holistic management of soil can remove some carbon dioxide from the air and do it for decades to come. This can provide quite a few other benefits to society, such as food, timber, erosion and flood control, improved wildlife habitat, and scenic values. It is not  high tech nor does it does it require rare or expensive materials. It employs and educates many people, including the poorest, all over the world. Well now, it looks pretty good, doesn’t it?

This article was prompted by a recent extended review from Yale University.

Climate Change Impacts on Global Food Security

Review by S. Tom Bond, Ph.D., Retired Chemistry Professor & Resident Farmer, Lewis County, WV, August 20, 2013

FrackCheckWV has referred its readers to the recent issue of Science which has over 50 pages of articles on the changes in natural systems in changing climates.  Being both a farmer and someone who enjoys a good meal encourages me to think about what future possibilities would be.  Food security, the ability of individuals to secure enough of the right kinds of food to sustain them, is also a very important political consideration.  This article is a condensation of “Climate Change Impacts on Global Food Security, appearing on page 508 of the August 2, 2013 issue of Science.

Food security has four factors.  The first is production of sufficient quantities of the right kinds of food.  Each human needs not only energy, but protein and other nutrients.  The second is access.  There must be transportation and distribution to reach the individual, and in some cases this doesn’t exist.  In urban settings it has to be paid for, so the individual must have sufficient  steady income. Third, there must be adequate utilization – facilities to prepare the food, including cooking and clean water for sanitation that are needed so physiological needs can be met.  The fourth is stability of supply, so that an individual can have adequate food at all times. 

Production, access, facilities to prepare and year-round supply.  All are needed by every individual if they are to survive.

It is estimated that  the undernourished in terms of calories has been reduced from 980 million to 850 million in the two decades from 1992 to 2010-12, but judging from under-weight, stunted-growth and health surveys, 2 billion people still suffer from micro-nutrients today.  Moreever, this seems to have been getting worse since 2007 due to pressures from food prices, extreme climate events and forced changes in diet.

Such pressures ae expected to build in the future.  Demand for food is expected to increase by 50% by 2030, as the global population increases.  Climate change could dramatically influence the progress toward reduction of hunger.

Present studies usually think in terms of production only, ignoring the other factors  mentioned above.  Even with sufficient calories, physical and mental factors can be influenced by nutrients, ability to prepare, and daily availability.  Remember the phrase “give us this day our daily bread?” It is very serious business for someone on the edge of starvation.  Data about food availability taken from aggregate reckoning is not adequate to completely understanding of the situation.   Surprisingly, the first analysis even from this limited perspective was not published until 1994.

This study was by Rozenzweig, Parry and others. It showed there is great variation in yields, highest yields the developed North of Europe and America, decreasing across Africa and South America.  Further work has shown that crops are more negatively affected by stress in the tropics, and so coincides with countries that presently have high burden of hunger.  It seems likely that food effects of climate change will be more severe in areas which already have a problem.

Food access is better understood.  For individuals it is largely a mater of income and rights.  Findings in this area show clear linkages between economic development and resilience to climate change.   In other words, if you have to buy food, you are better able to get it when you have more income.  On the other hand, if one’s assets are drawn down, if one must change jobs,  if migrating, etc., one is more vulnerable. 

If global warming changes location of production of biomass, which includes not only food, but also fiber and timber, trade in these commodities will change and consequently prices.  The resources of production , such as land and water access, will increase in value.  Such structural problems will lead to more appropriation of the assets of the poor, such as “land grabs” by external and foreign interests.  (Such is going on now at the fringes of tropical forests, in Africa, Madagascar  and Southeast Asia by Middle East oil potentates, and European, American and Chinese investors.  – Author’s note).

Utilization will be effected by less water in some areas, droughts and floods.  Higher temperatures will increase water-born disease, particularly diarrheal disease, and uptake of microneutrients may decrease.  Pesticides may come into even greater use due to increased abundance of pests.

Global urbanization results in changes in lifestyle, including higher caloric intake, poorer quality diet and relatively low physical activity, leading to obesity and chronic disease, even among the poor.  How this will link with effects of climate change is not known.

However it is clear that small shocks in supply or demand will have great effect on prices, and thus on food supply of the poor. Aggressive bioenergy projects, when applied by the political economy, can have great effect on food supplies.   Ethanol for fuel in the U. S. caused food riots in other countries, because the global price went up.

Finally, “This complex system of risks can assume a variety of of patterns that could potentially collide in catastrophic combinations.”  This author’s conclusion is that food supply can be handled as large scale management concern, or simply left to see who can make the most money from it, the latter being the most likely outcome at this point.