红壤小流域不同利用方式水土流失和有机碳流失特征研究

研究了红壤小流域不同利用方式的试验区水土流失和有机碳流失的特征 ,结果表明 :径流、泥沙及有机碳流失主要集中在 5月、6月及 8月份 ,其间径流流失量占全年流失量的 68.8%～ 73 .1 %,泥沙流失量和有机碳流失量占全年流失量的 90 %以上。径流量和泥沙流失量的大小顺序均为无保护性措施、侵蚀严重的试验区 5>粗放经营利用的试验区 1 >保护性经营利用试验区 2 >保护性经营利用试验区 4>恢复保护性植被试验区 3 ;流失的泥沙主要为推移质 ,有机碳流失量的大小顺序为粗放经营利用的试验区 1 >保护性经营利用的试验区 2 >保护性经营利用的试验区 4>无保护措施、侵蚀严重的试验区 5>恢复保护性植被的试验区 3 ,径流流失的有机碳和推移质流失的有机碳基本接近。从保护资源角度来看 ,恢复保护性植被试验区 3的利用方式控制水土流失和有机碳的效果最好。从农林利用角度来看 ,以有保护性经营利用综合性措施 (等高梯田、植被篱笆、农林间作等措施 )的试验区 2和试验区 4利用方式 ,既有利于水土保持 ,又有利于防止土壤肥力下降

Properties of Soil and Water Loss and Organic Carbon Loss from Small Watershed under Different Land Use Patterns in Red Soil Area

The properties of soil and water loss and organic carbon loss from red soil small watershed under different land use patterns were studied in Zhejing province. The results showed that runoff, sediment and loss of organic carbon concentrated in May, June and August when runoff accounted for 68.78%~73.08% of total loss in a year and both sediment and organic carbon accounted for more than 90% of total loss in a year. The amount of runoff and sediment in bed load form mainly were highest in catchment 5 with less covering vegetation and without soil conserving practice, next extensive farming catchment 1 with less comprehensive measurements for soil conservation, intensive farming catchment 2 and catchment 4 with comprehensive measurements for soil conservation, catchment 3 with vegetation conservation. The amount of loss of organic carbon was highest in catchment 1, next catchment 2, catchment 4, catchment 5 and catchment 3. The amount of organic carbon loss in runoff was equal to that in bed load. From the view of natural resource protection, vegetation conservation practice was the best way to control soil and organic carbon loss. From the point of agricultural production, soil conservation farming practices was the best way both for soil conservation and agricultural production.