新疆典型荒漠区单食性天花吉丁虫磷元素含量对环境的响应

磷是生态系统中重要的元素,驱动着生态系统的食物链及其相关的生态过程.沙漠生态系统P元素相对亏缺,了解该地区P元素对生物种群过程的影响及对生物多样性的保护有重要价值.通过定期监测土壤-植物(梭梭Haloxylon ammodendron)和昆虫(天花吉丁虫Julodis varioloris Pall)磷元素变化(磷含量及其RNA),分析土壤-植物-昆虫之间P元素的关系,结果表明:梭梭叶片中的C/P与土壤中有效P呈负相关,吉丁虫体内P和RNA与梭梭叶片中C/P呈负相关,与土壤中有效P含量呈正相关.吉丁虫中P与RNA含量直接受梭梭叶片中C/P影响,间接受土壤有效P影响,土壤和植物间P元素动力学可能是驱动天花吉丁虫种群变化的重要因素.自然条件下天花吉丁虫种群数量与其体内RNA含量变化一致,表明天花吉丁虫种群动态变化可以通过自然环境中磷元素的变化来评估,这可能是一个从微观角度研究昆虫种群变化的新方法.

The response of phosphorus in Julodis varioloris Pall to the environment in typical desert area of Sinkiang

The phosphorus (P) changes in soil, dominant plant (Haloxylon ammodendron) and main insect (Julodis varioloris Pall) in desert area of Sinkiang were periodically measured, and the P transference between soil, plant and insect was investigated. The results shows that Carbon/phosphorus (C/P) in Haloxylon ammodendron leaves negatively correlated with available phosphorus in soil. The P and RNA content in Julodis varioloris Pall negatively correlated with C/P in Haloxylon ammodendron leaves, while positively correlated with available phosphorus in soil. This indicates that the P and RNA in Julodis varioloris Pall were directly affected by C/P in Haloxylon ammodendron leaves, and indirectly affected by available phosphorus in soil. The P dynamics between soil and plant may be an important factor that drive Julodis population change. The population of Julodis varioloris Pall was consistent with the changes of the P and RNA contents in natural environment. It demonstrates that the dynamic change of Julodis population in desert area can be estimated by the changes of the P and RNA contents. This gives us a new way to study insect population in microcosm.