南方红壤丘陵区杜仲和油桐人工林水土保持效应的比较

Ecological Benefit of Soil and Water Conservation of Eucommia ulmoides and Vernica fordii Plantation in Hilly Red Soil Region,Southern China

对南方红壤丘陵区杜仲和油桐人工林土壤蓄水功能、径流及泥沙流失特征进行监测,对比研究2种人工林的水土保持效应。结果表明:杜仲人工林林冠枝叶最大持水容量及林地凋落物吸水容量均高于油桐人工林;杜仲林地0～140cm土层年均土壤蓄水量达到239.7mm,高出油桐林地4.1%;2002—2005年油桐人工林年均径流深为75.1mm,是杜仲人工林的2.6倍;油桐林地年均土壤侵蚀模数达到19.6t.km-2,是杜仲林地的2.9倍。杜仲林的土壤物理性质(土壤密度、最大持水量、渗透速率和毛管孔隙度)优于油桐林,其涵养水源的功能强于油桐林;杜仲人工林枝叶繁茂,其密度及盖度均高于油桐林,其控制水土流失的效果比油桐林好。作为水土保持树种,杜仲比油桐具有更好的水土保持效应。

Comparative experiments on the function of soil water storage and characteristics of runoff and sediment loss under Vernica fordii plantation and Eucommia ulmoides plantation in the hilly red soil region were applied.The results showed：Canopy maximal water holding capacity and litters sopping up water capacity of E.ulmoides plantation were higher,compared with V.fordii plantation,as well as soil water content,and soil water content under E.ulmoides plantation reached 239.7 mm between 0 and 140 cm beneath ground,which is higher than the other by 4.1%.Annual average runoff and sediment loss under V.fordii plantation were 75.1 mm and 19.6 t·km^-2 from 2002 to 2005,which were 2.6 times and 2.9 times of E.ulmoides plantation,respectively.Soil physical properties（such as water holding capacity,density,porosity and infiltration rate）and the complexity of vegetation structure（characterized by canopy,density and vegetation fraction and so on）in E.ulmoides plantation were more prior than that in V.fordii plantation,thus the function of soil water storage capacity and soil and water conservation were better than the later.As retentive tree species on soil and water conservation,E.ulmoides plantation has better benefits than V.fordii plantation.