August 4, 2009
Advances in ecology increasingly reveal that conventional agricultural practices have detrimental effects on the landscape ecology, creating problems for long-term sustainability of crops. In a series of sessions at the Ecological Society of America's Annual Meeting, ecologists will present their ideas on how our agricultural practices can take lessons from natural environments.
Reduced tilling improves soil microbe biodiversity
The idea of using biological instead of chemical methods to create healthy croplands doesn't include just above-ground approaches. Soil bacteria can affect the growth and success of crop plants by fixing nitrogen, aiding in the uptake of nutrients and decomposing dead organic matter. Some current farming practices, however, may disrupt the soil ecosystem and decrease the effectiveness of the microbe community.
In his poster, Shashi Kumar of Texas Tech University will explore the relationship between conventional tilling and low-tilling practices on farms in semi-arid areas of west Texas. In areas where soil tilling was kept at a minimum, Kumar and his colleagues found a higher diversity of soil bacteria; conventional tilling produced lower bacterial diversity.
Kumar says that conventional tillage systems disrupt soil particles and decrease soil pore size, which can lead to decreased water and soil access for microbes. Although he recognizes that tillage is necessary, he thinks that farmers can reduce their tillage, even in semi-arid regions, to promote soil bacterial biodiversity.
"We are currently using so many different crop management systems, like pesticides, insecticides and fungicides, which are damaging to our soil system," Kumar says. "Why shouldn't we focus on biological methods, since the bacteria are already there?"