环青海湖不同草地类型昆虫群落多样性研究

Structure and diversity analysis of insect community in different grassland types in Qinghai Lake

摘要:

【目的】 调查环青海湖地区高寒草甸、沼泽化草甸以及人工草地和山地干草原交界地带的昆虫多样性，为草地生态健康和草地生态恢复提供理论依据。【方法】 采用马氏网诱捕昆虫，运用多样性指数等统计分析不同草地昆虫群落结构及其多样性。【结果】 共采集昆虫样本36 990头，隶属于9目57 科，其中双翅目（Diptera）个体数最多，占40.35%。3种草地类型采集昆虫数量表现为交界地带草地＞ 高寒草甸＞沼泽化草甸；从昆虫在不同草地类型分布上来看，高寒草甸昆虫12 684头，隶属于9目43 科，占调查总个体数的34.29%。沼泽化草甸上的昆虫4 198头，隶属于9目41科，占调查昆虫总个体数的11.35%。交界地带草地共捕获昆虫20 018头，隶属于8目52科，占调查总个体数的54.12%。不同草地类型昆虫群落多样性指数随季节的变化而发生变化，其中Shannon-wiener多样性和Pielou均匀度的第一峰值均出现在8月中旬，而Simpson优势度和Margaelf丰富度指数出现情况则与其相反，最低值出现在8月中旬，且沼泽化草甸昆虫群落的Pielou均匀度指数显著低于其他两类型草地，交界地带草地昆虫的Margaelf丰富度指数显著高于其他两类型草地（P＜0.05）。高寒草甸和交界地带草地的昆虫物种相似度表现为极度相似。【结论】 环青海湖地区昆虫群落多样性指数和均匀度指数呈季节性变化趋势。人工草地和山地干草原交界地带草地的昆虫物种最丰富，高寒草甸次之，沼泽化草甸昆虫物种多样性最低。双翅目昆虫为3个不同类型草地的优势类群。

Abstract:

【Objective】 Insect community composition and biodiversity characteristics of grassland can provide re search basis for grassland ecological environment monitoring. The insect diversity of alpine meadow，marsh meadow， artificial grassland and mountain steppe in the area around Qinghai Lake was investigated to provide basis and guid ance for grassland ecological health and grassland ecological restoration.【Method】 The community structure and di versity of insects in different grassland were analyzed by using the diversity index.【Result】 A total of 36990 insect samples were collected，belonging to 9 orders and 57 families，among which Diptera accounted for 40. 35%. The num ber of insects collected in the three grassland types was as follows：borderland grassland ＞ alpine meadow ＞ swamp meadow； According to the distribution of insects in different grassland types，there were 12684 insects in alpine meadow，belonging to 9 orders and 43 families，accounting for 34. 29% of the total number of individuals. There were 4198 insects in the swamp meadow，belonging to 9 orders and 41 families，accounting for 11. 35% of the total number of insects. A total of 20018 insects were captured from 8 orders and 52 families，accounting for 54. 12% of the total number. Insect community diversity index of different grassland types changed with the change of seasons. The first peaks of Shannon‐wiener diversity and Pielou evenness occurred in mid‐August，while Simpson dominance index and Margaelf richness index appeared in mid-August，and the lowest values appeared in mid-August. The Pielou even ness index of insect community in swampy meadow was significantly lower than the other two types of grassland，and the Margaelf richness index of insect community in the border area was significantly higher than the other two types of grassland.（P＜0. 05）. The similarity of insect species between alpine meadow and borderland grassland was ex tremely similar.【Conclusion】 The diversity index and evenness index of insect community in the area around Qinghai Lake showed seasonal variation. The insect species in the border area between artificial grassland and mountain steppe was the most abundant，followed by alpine meadow，and the lowest in swamp meadow. Diptera was the domi nant group of 3 different grassland types.