中文摘要：

以宁夏地区油松天然次生林（贺兰山、罗山）和人工林（六盘山）为研究对象，对其O～40cm土层细根生物量、土壤特性及两者之间关系进行研究。结果表明，3个地区油松林细根生物量集中分布于0～20cm土层，总细根生物量、活细根生物量及其所占比例大小关系表现为贺兰山〉六盘山〉罗山，死细根生物量呈相反规律。除表层土壤（0～20cm土层）含水量外，3个地区土壤含水量与土壤容重大小关系均表现为：六盘山〉贺兰山〉罗山，且随土层深度增加，土壤含水量逐渐减小，土壤容重逐渐增大。土壤全C、全N和全P含量大小关系表现为：罗山〉贺兰山〉六盘山。相关分析表明，该区油松天然次生林细根生物量与土壤水分、土壤容重相关性更大，人工林则与土壤养分如全N、全P等指标的相关性更大。

英文摘要：

Taking natural secondary Pinus tabulaeformis forests （occurring in Helan Mountain and Luos- han Mountain） and artificial P. tabulaeformis forests （in Liupan Mountain） in Ningxia as research ob- jects, fine root biomass and soil properties in 0--40 cm soil layer, as well as their relationships were exam- ined. The results indicated that fine root biomass in three regions was mainly distributed in 0--20 cm soil layer. The total fine root biomass, alive fine root biomass and their corresponding ratios were ranked in the order of Helan 〉Liupan 〉Luoshan. While the dead fine root biomass followed an opposite pattern. Soil water content and soil bulk density of 0--40 cm soil layer were ranked in the order of Liupan 〉Helan 〉Luoshan with the exception of soil water content of surface soil （0--20 cm soil layer）. With the increase of soil layer depth, soil water content gradually decreased and soil bulk density gradually increased. The total C, N and P contents in the soil were ranked in the order of Luoshan〉Helan 〉Liupan. The correlation analysis between fine root biomass and soil properties exhibited that fine root biomass was more relevant to soil water content and soil bulk density in natural secondary P. tabulaeformis forests, and fine root biomass was more relevant to soil nutrients such as total N content and total P in artificial forests.