Effect of selected bioengineering measures on runoff, soil loss, and cotton (Gossypium hirsutum L.) productivity in the semi-arid region of western India

Soil erosion and associated loss of soil nutrients and organic carbon are one of the major reasons for low crop productivity in major cotton (Gossypium hirsutum L.) growing areas of India. This calls for designing acceptable and low-cost bioengineering measures to enhance system productivity and soil health. Thus, a field study was conducted at Vasad, Gujarat, India from 2014 to 2017 to evaluate the efficacy of selected bioengineering treatments on cotton crop production and runoff and soil loss. The eight experimental treatments consisted of bio-filters of three grass species, viz.Para (Brachiaria mutica), Guinea (Megathyrsus maximus),and Napier (Pennisetum purpureum) at two strip widths (1 m and 2 m), field bund, and the conventional system as practiced by the farmers of the region. The treatments were tested in 45 × 10 m plots having the gauging facility for recording runoff and soil loss data. Rainfall, runoff, sediment concentration, soil loss, organic carbon, nutrient loss, and growth and yield parameters of grass barrier species and the cotton crop were recorded and analysed. The filter strip of Guinea sp. at 2 m width was most effective, reducing runoff by 30%, soil loss by 66%, nutrients loss by 69%, sediment concentration to 1/3rd, and soil organic carbon loss by 65%. The lowest runoff coefficient value of 0.209 observed among the filter strips in this treatment, indicated about 79% of rainwater was conserved in situ. The available soil nutrients increased by up to 42% and SOC concentration by 61%, and cotton equivalent yield by 25% than that of the conventional system. We concluded that Guinea grass filter strips of 2 m width planted at 45 m spacing in cultivable lands having 2% slope minimized runoff, soil loss, nutrient loss, improved soil fertility and enhanced cotton productivity. •Bioengineering measures were evaluated for erosion control and better cotton production.•2 m wide filter strips of Guinea grass (2 m/GG) was the most effective treatment.•2 m/GG reduced runoff by 30%, soil loss by 66%, nutrient loss by 69% and conserved 79% rainwater.•2 m/GG was better than contour bunds in terms of soil loss and crop production.