Conservation tillage (CA) systems are gaining increased attention as a way to reduce the water footprint of crops by improving soil water infiltration, increasing soil moisture and reducing runoff and water contamination. The concept of water footprint is defined as the total volume of freshwater used, directly or indirectly, to produce a product or process including the total amount of water required in agriculture for growing crops. About 141 million and 645 thousand hectares of land in the world have been destroyed by erosion because of inappropriate tillage operations. The total amount of 26 billion tons of soil eroded is estimated and about 2 billion tons comes out from Iran. Parallel to the erosion, loss of soil organic matter that occurs on to several factors, farming has become more challenging. Many strategies exist to combat soil degradation through erosion and compaction on agricultural fields. One of these strategies is conservation agriculture (CA). Reduced or no-tillage techniques, together with crop residue management and crop rotation are the pillars of CA. The term reduced tillage covers a range of tillage practices but it never involves inverting the soil. In this way, soil disturbance is minimized and crop residues are left on the soil. Studies in many European countries have shown that CA can indeed be very effective in combating soil erosion. However, soil and water conservation do not appear as main drivers in farmers’ decisions to shift or not to CA. Economic factors tend to be more important, but there are a lot of uncertainties on this domain. Studies show that production costs are mostly reduced, mainly by reduced fuel costs. Although many European studies have investigated the effect of reduced soil tillage on crop yields, a lot of uncertainties still exist.
کلید واژگان :Conservation tillage, No-till, Ridge-till, Tillage Management, Erosion
ارزش ریالی : 300000 ریال
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