贺兰山鞘翅目昆虫的地理分布格局及区域分异研究

Mt.Helan is one of the six great biodiversity centres in China,which is the only biodiversity centre in Northern China. Study on biodiversity geographical distribution patterns and formation mechanism in Mt.Helan is important significance of conservation biology. In this project, we try to elucidate the geographical patterns of diversity of Coleoptera insects in Mt.Helan and their correlation with regional differentiation. First, we will establish the two databases, which one of them is the landscapes pattern database based field survey combining ecological environment basic maps and special subject maps, and the other is the Coleoptera species diversity database including information of species,distribution and habitats and so on through the field investigation.Second, based on GIS model of species range maps the distribution patterns of Coleoptera species are studied. By the beetle habitat analysis, some equal-area quadrangle grids are used as geographic units to collect distributional data of the species supported by MapInfo Professional Version.All the grids with the distributional data of binary attribute are divided into groups by hierarchical cluster analysis according to Euclidean distance. Index of G-F, species biodiversity and regional differentiation in the grids are calculated according to the occurrence frequency of species in grids. Finally, based on the above model and calculation, we will analyze the geographical patterns of diversity of Coleoptera insects in Mt.Helan and their correlation with regional differentiation, and then elucidate formation mechanism on Coleoptera species biodiversity geographical distribution patterns in Helan Mountains. Moreover, we will investigate the effect of geological history and topographical patterns on the geographical patterns of species diversity.

贺兰山是我国6大生物多样性中心之一，也是我国北方唯一的生物多样性中心，研究该地区生物多样性的地理分布格局及其形成机制具有重要的保护生物学意义。本项目以贺兰山环境基础图件、专题图件和实地勘测相结合，绘制景观生态图；结合路线法和样方法，系统调查鞘翅目昆虫的种类、分布、生境等数据；建立贺兰山景观格局与鞘翅目昆虫物种多样性信息数据库；基于GIS技术，通过生境分析，以等面积栅格法收集鞘翅目昆虫的二元分布数据,采用多元分析的分层聚类方法和相关性研究，生成鞘翅目昆虫的地理分布格局，计算区域分异强度（指数），并分析二者之间的关系，并阐明区域分异强度对物种多样性影响，进而解释现代自然条件下，贺兰山鞘翅目昆虫地理分布格局及其形成机制，并尝试阐述地质历史引起的区域分化对甲虫多样性地理分布格局的影响。

研究贺兰山鞘翅目昆虫地理分布格局及区域分异对探究该地区生物多样性的地理分布格局形成机制和生物多样性保护具有重要意义。通过本课题实施，全面系统地调查并鉴定贺兰山鞘翅目昆虫39科251属466种，较文献记载增加193种，步甲科和拟步甲科为优势科，初步建立贺兰山鞘翅目昆虫生物多样性数据库。区系组成以古北界成分占优势（289种，占总种数的62.02%），并以蒙新区为主，与华北区和东北区的关系较为密切。. 以栅格分析法研究鞘翅目昆虫多样性的地理分布格局及其区域分异。结果表明，鞘翅目昆虫多样性和区系分化强度最高值出现在贺兰山中段，自北向南方向，科、属、种的多样性及属和科水平的区系分化强度均表现明显的单峰曲线变化趋势，贺兰山南段科、属、种的多样性和区系分化强度比北段高，科的区系分化强度范围比属的区系分化强度宽。自西向东方向，科、属、种的多样性以及属和科水平上区系分化强度均呈现明显的不对称单峰曲线变化趋势，贺兰山西坡科、属、种的多样性和属和科的区系分化强度高于东坡，且科的区系分化强度范围比属的区系分化强度宽。鞘翅目昆虫物种多样性随区系分化强度的增强而增加。科、属区系分化强度与表征地形复杂度的单位栅格海拔高差之间存在显著正相关。区系分化强度较大的区域主要集中在地形复杂的贺兰山中段地区。鞘翅目昆虫物种多样性地理分布格局的形成可能与该地区的地质历史、地形以及由此引起的昆虫区系分化有关。. 地形对甲虫物种多样性分布格局的影响研究表明，海拔、坡度和平面曲率对拟步甲昆虫的分布有显著影响。拟步甲昆虫丰富度和多样性均与海拔呈显著的线性关系，个体数量与平面曲率呈显著的二次曲线关系。拟步甲昆虫的分布不受坡度和坡向明显影响，但其倾向于0°-15°坡度和西北坡向聚集。海拔、坡向、坡度、剖面曲率和地形湿度指数的综合作用对步甲物种多样性分布格局有显著影响，其中，海拔对步甲分布影响最显著，说明甲虫物种多样性的分布格局受海拔为主的多种地形因子综合作用的影响。