Study of the Water Erosion under Conservation Agriculture in the Conditions of Northeastern Syria (Al-Hassaka

Abstract

Conservation Agriculture (CA) is considered as one of the new farming systems, which has been introduced to the region in order to maintain the agricultural soils from degradation and improving water use efficiency via preserving soil moisture content and enhancing rainwater use efficiency and the sustainable use of soils. CA depends on three basic pillars: no mechanical soil disturbance before planting or minimum soil tillage, permanent maintenance of crop residues on the soil surface and crop diversification/suitable crop rotation which includes a leguminous crop.  The Agricultural soils in the North East region of Syria, especially under rainfed conditions suffer of water erosion threatening the agricultural production and environment, causing a remarkable decline in the economic yield of the cultivated crops, so there was a need for introducing new farming systems other than the existing tillage-based conventional one, such as CA to stop soil degradation. An experiment was conducted at in the north of AL-Hassaka governorate (Al Qamshli) during the period 2013 – 2017 to evaluate the impact of CA along with crop rotation (barley – Vetch – Fallow) with leaving all the crop residues of the previous crop versus the convention tillage system on soil degradation.  The quantity of the eroded soil was significantly lower (75.6 kg ha^-1) under CA compared with the conventional system (1032.8 kg ha^-1). The rate of surface run-off was significantly lower un CA and the barley crop residues (5.8%), while it was significantly higher under conventional tillage system (25.8%), so CA reduced the water surface run-off by five folds. The percentage of soil organic matter increased by 1.31% under CA and vetch crop compared with 1.41% under barley crop, while the soil organic matter did not exceed 0.85 – 0.89% under conventional tillage system. The available of phosphorous was significantly higher under CA system (6.5 – 9.5 ppm). CA system was effective in reducing the soil erosion by 10 – 18 folds compared with conventional tillage system and the barley residues played a pivotal role in protecting the soil from erosion by water compared with vetch residues and fallow system, which minimized the soil erosion by six folds