Conservation tillage improves soil properties and crops yields in North China

Abstract

China has 33Mha arid and semi-arid land which is largely located in the 16 provinces of North China. In dryland farming of these areas, wheat (Triticum aestivum) and maize (Zea mays L.) are the main crops that are constrained by adverse weather, water shortage and poor soil fertility. In current cropping system, all the crop residues are removed or burned after harvest before mouldboard ploughing. However, these practices have contributed to an exacerbation of soil, water and nutrient losses. The severe land degradation and serious environmental problems have led the Chinese government to emphasize the need for the implementation of farming practices which contribute to the conservation of soil and water. A vital approach is the use of conservation tillage, which is defined as any tillage and planting system that leaves 30% of crop residue on the soil surface after planting. The Chinese Ministry of Agriculture has promoted the widespread extension of conservation tillage since 2002, and by the end of 2009, the conservation tillage area in China was over 3Mha. This paper reports the impacts of conservation tillage on soil properties and crop yields in dryland farming areas in North China.