滇西北典型高原湿地昆虫多样性及适应性机制研究

The study and protection of wetland insect diversity is a hot issue in the field of international wetland science research. The northwestern Yunnan plateau wetland which is located at the important area of "Southwest China", is one of the 34 biodiversity hotspots in the world; nevertheless its ecological environment is fragile. Understanding the insect diversity of the wetland and further investigation of the impacts of wetland degradation on the insect diversity is important for the protection of wetlands. A typical plateau wetland (Napahai) was selected as our research area. The variation of the composition and diversity of insect communities in the natural primary wetlands, disturbed degraded wetlands and degraded wetland restoration areas will be compared and analyzed. The systematic and dynamic process of insect diversity in plateau wetland degradation and restoration is important for clarifying the function of insect communities and the correlation between insect diversity and specific environmental factors in wetlands. We also aim to explore the adaptive mechanism of insects to the wetland environment, which would lay the theoretical basis for the wetland environmental monitoring according to the insect sensitivity. This project has significant practical importance for the wetland protection.

湿地昆虫多样性的研究和保护是当前国际湿地科学研究前沿领域的热点问题，滇西北高原湿地位于全球34个生物多样性热点地区之一的“中国西南地区”的重要地带，生物多样性极为丰富而生态环境脆弱。了解该区域湿地昆虫多样性，湿地退化对昆虫多样性的影响？影响程度如何？是科学应对湿地退化、加强湿地保护的重要依据。本课题选择滇西北高原湿地纳帕海为研究地点，通过对比研究自然原生湿地、干扰退化湿地以及退化湿地恢复区域中昆虫群落组成和多样性的变化，开展系统、动态的高原湿地退化与恢复过程中昆虫多样性的研究工作，对阐明湿地昆虫群落的功能，揭示昆虫多样性与具体环境因子及其指标的相关性，探讨昆虫对湿地环境的适应性机制以及根据不同群落昆虫对相关环境因子的敏感性筛选出指示昆虫奠定理论基础，为湿地环境监测、评价及生态恢复提供理论依据，对科学管理、利用湿地有着重要的现实意义。

本课题以受放牧影响的滇西北典型高原湿地为研究区域，研究已长期退化为草甸的区域在恢复过程中昆虫多样性随植被群落组成与结构、土壤理化性质改变和环境因素的变化，阐明了湿地退化与恢复过程中相关因子的作用机制。主要进展如下：（1）持续三年季节性开展昆虫群落组成及多样性动态调查工作，完成了样方中鳞翅目、膜翅目、双翅目、半翅目及鞘翅目昆虫的鉴定和数量统计，首次阐明了滇西北高原湿地昆虫多样性。（2）完成退化草甸区域和围栏恢复区域植被种类鉴定和群落指标测定，围栏有利于植被高度和覆盖度的恢复，基于线性回归模型分析结果表明植被高度和覆盖度变化通过上行效应决定了生态系统中昆虫群落的构建，直接影响着昆虫多样性。（3）围栏有利于退化草甸土壤自然含水率和土壤孔隙度的恢复，通过SEM结构方程模型分析结果表明土壤理化性质与湿地植被相互作用，共同影响昆虫多样性，土壤理化性质的恢复对昆虫多样性起着重要的间接作用。（4）基于Raup-Crick指数零模型分析探讨昆虫群落构建机制，研究结果表明生态位理论的确定性过程在湿地昆虫群落构建中起着主导作用，恢复草甸区域的昆虫群落多样性更高，退化草甸区域的昆虫群落更相似，干扰通过确定的非生物因素植被高度和覆盖度决定了生态系统中昆虫群落的构建。