Agricultural green revolution provided benefits and problems
The agricultural green revolution began in the mid 20th century. The "green" did not have the environ-mental connotation we expect today but rather referred to spreading efficient productive crops worldwide.
The revolution was preceded by tractors replacing animal power in farm fields. It transformed agriculture from the labor intensive small farm to the high yield huge agribusinesses we have today. The green revolution has been both beneficial and problematic.
The green agricultural revolution started in the developing world. The rising world population was outstripping the world food production. The U.S. Department of State Agency for International Development, the Rockefeller Foundation and the Ford Foundation sponsored research into the development of high yielding hybrids for wheat in Mexico and India and rice in India, Taiwan and Southeast Asia. The yields were increased by four-six times. Attention was given to developing better seeds for other staple food crops.
In addition to the hybridization, synthetic chemicals were developed in the effort to make farming more efficient and to increase crop yields. Among the synthetic chemicals that were introduced were pesticides, herbicides and synthetic fertilizers.
In 1939, Dichloro-Diphenyl-Trichloroethane, or DDT, was discovered to be extremely effective at killing a wide range of crop pests. It rapidly became the most widely used insecticide in the world. The success of DDT led to the synthesis of thousands of organic molecules in a search for chemicals to guard against the many insects damaging crops. The farmers were able to dramatically increase crop yields in the 1950s. Today, more than 20,000 pesticides are registered with the Environmental Protection Agency resulting in a multibillion-dollar industry in the United States alone.
The herbicide 2, 4-D came on the market in 1945. It was developed as part of the war effort to increase agricultural productivity. It was the first herbicide to distinguish between broad-leaved plants and grasses. Farm workers employed in weeding were replaced by herbicides. Atrazine was registered in 1958 for use on corn crops. Roundup was introduced in 1974. Roundup usage has now skyrocketed with the widespread use of Roundup Ready corn, soybeans and cotton. The application rates per acre of Roundup Ready crops are also increasing due to emergence of resistant weeds.
Most of the fertilizers and fertilizer technology used around the world today were developed or improved during the 1950s to 1970s by scientists and engineers at the Tennessee Valley Authority. Chemical nitrogen is still largely generated from ammonia plants. Ammonia is produced by combining N from the air with hydrogen at high temperature and pressure. The hydrogen is derived from natural gas, which accounts for around 80 percent of the production cost. The fertilizers phosphate and potassium are mined, respectively, from phosphate rock and potassium chloride.
At first blush, the green agricultural revolution has been extremely successful. Agricultural production increased fourfold between 1820 and 1975. During that same period, world population had a threefold increase. The Minnesota average corn yield was 175 bushels per acre in 2009 as compared to 30 bushels per acre prior to 1938. To this day, farmers have been able to feed the world. Given the continued surge in world population, there is doubt that future improvements in agriculture will be able to keep up with the pace of expansion of the population.
The green agricultural revolution has brought with it a multitude of problems that need to be considered in weighing the benefits and costs of the movement. Groundwater in southern Minnesota poses health risks due to high levels of agricultural chemicals. Drainage of farm fields is contributing to more rapid runoff of the spring melt. Farmers in developing countries are unable to profitably produce staple crops due to the dumping of cheap commodities into their markets. Crop pests and weeds are adapting and are becoming resistant to the chemicals that are being used for control. These are but a few of the challenges facing modern agriculture.
Conventional agriculture is yield driven and primarily produces tradable commodities. Food processors convert these commodities into the recognizable products that show up in supermarkets. We have become complacent purchasers of food and have been prevented from knowing who grows any particular food, what chemicals were used in its production and how much environmental damage occurred in the production of the food.
There are alternatives to this commodity-oriented food production system. Sustainable agriculture will be presented in the next installment.
Gregory Oja is a member of the Bemidji's Natural Choice Farmer's Market and sells under the farm name, Mattila. He practices sustainable agriculture in Hubbard County.