不同类型草原围栏封育对昆虫多样性的影响

Effects of different types of steppe fencings on insect diversity

中文关键词:天然草原  围栏封育  昆虫多样性  植被  相关性分析

keywords:natural steppe  enclosure  insect diversity  vegetation  correlation analysis

中文摘要:为探讨不同类型草原围栏封育对昆虫多样性的影响，于2023年春、夏、秋3个季节在宁夏回族自治区盐池县的温性荒漠草原、荒漠-温性草原过渡带和温性草原围栏封育区内外，采用陷阱诱捕法对植食性昆虫与捕食性昆虫进行系统监测，并分析2类昆虫在围封区内外的多样性差异，结合植被群落特征与昆虫群落进行相关性分析。结果显示：在3类草原中，2023年共采集到1 309头植食性昆虫和2 390头捕食性昆虫，分别隶属于49种和30种，总计3 699头。温性荒漠草原围栏封育区内部的昆虫物种数、个体数及多样性指数均低于外部；而荒漠-温性草原过渡带和温性草原围栏封育区内部的昆虫多样性指数则高于外部，但其优势度指数低于外部。同时，3类草原不同季节植食性昆虫和捕食性昆虫在围栏封育区内外部的发生量均存在显著差异。此外，植食性昆虫的物种数、个体数、多样性指数和均匀度指数均与植被高度呈负相关，而个体数则与植被频度和地上生物量呈显著正相关，多样性指数、均匀度指数亦与植物密度呈显著正相关。在围栏封育区内部，随着捕食性昆虫个体数增加，植食性昆虫的个体数量也随之上升，两者之间呈显著正相关。因此，在荒漠-温性草原过渡带和温性草原实施围栏封育措施能够有效提高生态系统中的昆虫多样性，从而降低某些害虫暴发成灾的风险。

Abstract:To explore the influence of fencing and enclosure in different types of grasslands on insect diversity. During the spring, summer, and autumn of 2023, systematic monitoring of herbivorous and predatory insects was carried out using the pitfall trapping method in three steppe types: temperate desert steppe, the transition zone between desert and temperate steppe, and temperate steppe, located in and around Yanchi County, Ningxia Hui Autonomous Region. The differences in insect diversity between the enclosed and unenclosed areas were analyzed, and the correlation between the vegetation community characteristics and insect communities was also examined. The results showed that a total of 1 309 herbivorous and 2 390 predaceous insects were collected in the three types of steppes in 2023, amounting to a total of 3 699 insects belonging to 49 species of herbivorous insects and 30 species of predaceous insects. In the temperate desert steppe, the species richness, individual numbers, and diversity indices of insects were all lower in the enclosed area than in the external area. However, in both the transition zone and the temperate steppe, insect diversity indices were higher in the enclosed area, while dominance indices were lower. Furthermore, significant differences were observed in the abundance of predatory and herbivorous insects between enclosed and unenclosed areas across various seasons within the three types of steppes. In addition, herbivorous insect species richness, individual numbers, diversity, and evenness indices of herbivorous insects were negatively correlated with plant height, while the individual number was positively correlated with plant frequency and aboveground biomass, and the diversity and evenness indices were also positively correlated with plant density. In the enclosed area, as the number of predaceous insects increased, the individual number of herbivorous insects also increased, and there was a significant positive correlation between them. Therefore, implementing fencing and protection measures in the transition zone between desert and temperate steppe and in the temperate steppe can effectively increase insect diversity in the ecosystem and reduce the risk of pest outbreaks.