Agricultural mismanagement of soils in all countries across the globe has resulted in soil degradation, with consequent negative environmental and economic impacts especially with the practice of continuous planting of crops.

Farmers in Brazil have taken the lead in development and conservation of soil. The biggest difference between the system adopted by Brazilian farmers and other countries is that the former have understood that conservation of soil is a long drawn system and not a one time application.

In order to create awareness among our valued readers of the Brazilian model of cotton cultivation, Fibre2fashion spoke exclusively to Mr Donald Reeves, to understand the cultivation methods adopted by the Brazilians. Mr. Reeves is an Agri-Research Leader with J. Phil Campbell Sr. Natural Resource Conservation Center, Georgia, an autonomous body under the USDA. Mr. Reeves has done extensive research on the Brazilian method of farming & is trying to get it adopted in America.

Mr. Reeves said This environmentally friendly system involves growing a grass or cereal cover crop which makes a large amount of biomass, usually 4 to 8 metric tons per hectare of dry matter. Various cover crops are used, but the most popular in the main cotton growing region, the Cerrado, is pearl millet.

The growing season of Pearl millet complements that of cotton. A few weeks prior to cotton planting, the cover crop is terminated with herbicide or mechanically using large rollers or chain drags.

This lays the stems of the cover crop flat on the soil surface, providing a thick mat of residue or straw which completely covers the soil.

The cotton is then seeded directly into the soil beneath the mulch using specially designed no-tillage planting equipment. The soil remains undisturbed except for a narrow (2-5 cm wide) area where the seed are placed.

Mr. Reeves added The benefits are multifold. The soil is not touched by a plow, and the cover crop mulch completely covers the soil, protecting it from wind and soil erosion, shading and cooling the soil for better root growth, suppressing weeds and reducing the need for herbicides, and dramatically conserving water.

When asked about improvement in yields, Mr Reeves asserted by saying Yields are almost always increased compared to the older system of using the plow. The mulching effect of the cover crop combined with the elimination of tillage increases the infiltration of rain, reducing wastes from runoff and erosion. This reduces drought stress on the cotton, increasing yields.

Yields are also increased by the reduction of competition from weeds. Finally the soil productivity is increased over time from the addition and conservation of soil carbon in organic matter. Improved soil productivity results in better root growth, increased biodiversity and fewer diseases, and better use of plant nutrients.

In the longer term, this system takes carbon from the atmosphere during photosynthesis and stores it in the crop residue and soil. This process reduces carbon dioxide in the atmosphere and helps to mitigate global warming.

The carbon is stored in the soil organic matter and this improves the soil quality and productivity of the soil, leading to higher yields over time.

To a question whether the system leads to better quality, Mr. Donald said Cotton grown with this system is of the same quality as that grown with traditional methods, but less environmentally friendly means. If anything, fibre quality can be improved because there is less drought stress on the cotton plants in this system.