The identification and adoption of no-till practices can reduce the soil erosion caused by soybean production, as can linking the adoption of such practices to government subsidy programs. A related policy initiative to reduce the harmful impacts of the industry is to remove subsidies that encourage soybean expansion for artificial markets.
Clearly, one conservation strategy should be to identify and analyse the implications of soybean expansion for natural habitat. Finally, strengthening command-and-control regulatory systems can reduce the environmental problems associated with soybean cultivation. Each of these strategies is discussed on this website separately. However, their cumulative impacts are greater than their individual ones.
Lessons to be learnt from China
The strategies that are most appropriate to reduce the impacts of soybean cultivation will vary considerably from one country to another. China has produced soybeans longer than any other country. Today, the country's production is seriously affected by pests. Some 8,800,000 hectares of land have been affected by losses estimated at some 32,900 metric tons. In one of the areas most used for soybean production, the following measures are taken to prevent diseases: crop rotation, deep ploughing, late planting, manuring, and the application of pesticides as needed (Tengnas and Nilsson 2002).
These strategies, at the other end of the spectrum from input intensive no-till cultivation with or without transgenic varieties, suggest that techniques will vary widely from country to country and will depend on specific conditions and pests.
The example of United States
In the United States, the better management practices (BMPs) that have evolved are quite different. In this country precision agriculture and the targeting of agrochemicals to address specific needs have resulted in a reduction of the overall average use of chemical inputs per hectare.
Likewise, soil erosion has been reduced by standard conservation techniques including terracing, strip cropping, planting cover crops, maintaining waterways, and improving road construction and machine access. Organic matter content in the soil has been improved through mulching and conservation tillage programs such as reduced tillage and spring tilling.
The benefits of No-till/Conservation tillage techniques
No-till production leaves virtually all crop residues on the surface while reduced tillage (or low-till) leaves some 15-35% of crop residues on the surface (Schnittker 1997). Conservation tillage provides more ground cover, more available waste grain for food, and less disturbance of nesting sites than conventional tillage. All of these practices have a net positive impact on biodiversity and ecosystem functions. Most of these practices also increase yields and profits.
BMPs roadblocks
There are a number of impediments to the adoption of BMPs, however. At a recent meeting in Iowa hosted by Natural Resources Defence Council (NRDC 2001), a number of issues were identified that affect overall pesticide use. Perhaps the most important is that the adoption of BMPs requires a greater time commitment to management, yet farm size is growing in most soybean-producing areas so there is less time available to devote to each hectare of production.
