Influence of crop management on water use of agricultural products. Case study: soybeans (Glycine max) in conventional tillage versus no-tillage in Argentina

PIASTRELLINI, R.; ARENA, A.P.; CIVIT, B.

Nantes

Conferencia; SETAC Europe 26th Annual Meeting; 2016

Society of Environmental Toxicology and Chemistry

The aim of this study is to analyze the influence of tillage systems in assessing consumptive use of water in agricultural products. A new procedure which allows the incorporation of the water balance of the soil on the green and blue water footprints calculation is presented. For this, an adjustment of cropevapotranspiration and surface runoff is performed, taking into account the effects related to the presence of stubble, crop cover and surface roughness. The case study of soybean (Glycine max) in conventional tillage and no-tillage in Argentina constitutes the first application of this procedure. The results confirm that no-tillage reduces soil evaporation, prolongs the water storage period in the soil, delays the onset of the surface runoff and decreases runoff depth. This improves the water availability to satisfy crop needs and therefore increases the consumption of green water. The increased water availability increases the crop productivity, resulting in a diminution of green water footprint. If the soybean is grown under irrigation, the increase on the green water consumption corresponds to blue water savings. The considerations of tillage systems in assessing green and blue water footprints would be highly relevant in products derived from crops whose productivity is evenly influenced by hydric stress throughout the growing cycle. Likewise, tillage effects on the green and blue water footprints would be of greater magnitude for crops grown in regions with regular rainfall, or where the periods of greatest rainfall take place during the stage of crop development.