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[目的]揭示滇东南岩溶地貌下土壤物理性质对油茶地蜂Andrena camellia Wu种群数量的影响.[方法]测定并比较江西宜春丘陵地貌下具油茶地蜂“筑巢适生区”和无“筑巢适生区”的油茶林地,以及云南文山岩溶地貌下“峰丛”和“洼地”中油茶林地的土壤硬度值、容重、含水量、温度和颗粒组成,并测定四类型样地中油茶地蜂巢穴密度和访花多度.[结果]滇东南岩溶地貌中峰丛和洼地样地土壤硬度、容重和温度显著高于江西宜春具“筑巢适应区”样地,但土壤含水量显著低于江西宜春具“筑巢适应区”样地.未检测到不同林地间土壤颗粒组成百分率差异.滇东南岩溶地貌中峰丛和洼地样地油茶地蜂巢穴密度和访花多度显著低于江西宜春具“筑巢适生区”的样地.土壤物理性质影响油茶地蜂巢穴密度.土壤硬度可作为重要指标,用于快速、简便检测油茶林下土壤是否适应油茶地蜂筑巢.滇东南油茶样地土壤硬度系统测定结果表明,岩溶地貌典型样地土壤硬度高于适应油茶地蜂筑巢的土壤硬度阀值(2.50 MPa).[结论]滇东南岩溶地貌下油茶林地土壤物理性质不适应油茶地蜂筑巢.“,”[Objectives] To investigate the influence of soil characteristics on population of digger bees Andrena camellia Wu in a Karst region in Wenshan, Yunnan province. [Methods] We selected two types of tea-oil camellia orchards in Yichun, Jiangxi province,one type having good nesting soils (NS) for digger bees and another without good nesting soils (NNS). We also selected two types of orchards in the Karst region of Wenshan, Yunnan, one type called peak cluster (PC) and another called depression area (DA). Soil penetration resistance, bulk density, water content, temperature, soil particle size, nest density, and visitor abundance, were measured in the four types of orchards. [Results] PC, DA and NNS had significantly higher soil penetration resistance, bulk density and temperature, but significantly lower water content, than NS. No significant differences in soil particle size between the four types of orchards were detected. PC, DA and NNS had significantly lower nest densities and visitor abundance than NS orchards. Nest density was significantly, and positively, correlated with soil traits and soil penetration resistance could be used as an indicator to determine whether soils were suitable nesting sites for digger bees. We systematically measured the soil penetration resistance of all PC and DA orchards in the Karst region and found that these soils were compacted, with values higher than the threshold (2.50 MPa) below which digger bees prefer to build their nests. [Conclusion] The soils in the Karst region in Wenshan, Yunnan are not suitable nesting sites for digger bees, which may have resulted in their decline in this region.