PPT Slide
There are several soil and crop management practices that can alter soil organic matter levels and biological activity. These include: 1) Reduced tillage systems that slow the decomposition of crop residues and limit erosion of the higher organic matter topsoil, 2) Diversified rotations that include legumes, deep-rooted crops, and high-residue crops; this adds nitrogen, recycles nutrients from the subsoil, and stimulates a diversity of soil organisms, and 3) Growing cover crops, which increases organic matter inputs, recycles nutrients, reduces runoff and erosion, and can also add nitrogen if they include legumes. Intercropping, double-cropping, living mulches, and similar practices that increase the area or time of vegetative cover have similar effects. A fourth method is amendment with other organic materials, which could include manures, sludge, leaves, grass clippings, and other high carbon residues and wastes.