The effects of plant hedgerows on soil erosion and soil fertility on sloping farmland in the purple soil area
植物篱对紫色土区坡耕地水土流失及土壤肥力的影响

Effect of using plant hedgerows to control soil and water losses has received wide recognition and this technology has been applied in many areas in the world. Yet, studies on its effect on soil fertility of sloping lands are rare. Using an eight-year fixed field experiment, the authors investigated the effect of two different hedgerows against the control treatment on soil fertility. Results showed that clay particles tended to accumulate above the plant hedgerows and to be eroded downward below the hedgerows along contour lines across the field. Distribution of soil organic matter and all plant nutrients except K showed the same pattern as the clay particles. Potassium (K), however, was evenly distributed in the field without any noticeable influence from the hedgerows. Since the fixed experiment started, soil P has kept accumulating, while soil organic matter and K are in depletion. The results suggest accordingly better nutrient management practices on the sloping lands by using reduced rates of P and increased rates of farm manure and K. Taking the sloping field as a whole, special attention in nutrient management should be given to the soil stripes the portions below the plant hedgerows suffering from more serious soil erosion.