Question

Does the retaining stubs in the fields helps the soil?

Answer 1

Retaining stubble (the stems and roots of a harvested crop) is beneficial in a number of ways:

1. Stubble increases surface roughness, thereby reducing wind velocity and the potential for wind erosion.
2. Stubble, and the roots attached to it, stabilize soil against erosion by water.
3. Stubble protects soil aggregates from destruction by raindrop impact, thereby keeping the soil surface more porous and absorptive.
4. Stubble adds organic matter to the soil and increases microbial activity.

OR

Stubble used to be burnt because it improved weed control and creates easier passage for seeding equipment. However, retaining stubble has several advantages for soil fertility and productivity.

1. One of the important benefits of stubble retention is reduced soil erosion. Retaining stubble decreases erosion by lowering wind speed at the soil surface and decreasing water run-off. To minimize erosion approximately 50 % ground cover is required and adequate stubble needs to be maintained for 6–8 weeks following seeding (Leonard, 1993).
2. Another advantage of retaining stubble is that it increases soil moisture content by decreasing run-off and increasing infiltration. However, the potential benefits of decreased run-off and increased infiltration will depend on the timing and intensity of rainfall as well as the quantity and orientation of stubble and soil properties.
3. Retaining stubble increases the input of carbon to soil. Stubble is approximately 45 % carbon by weight and therefore represents a significant input of carbon to soil. It can take decades for retaining stubble to increase the amount of total organic carbon in soil.