甘肃省天然草原蝗虫群落结构及生态位

Diversity and spatial niche of grasshoppers in alpine steppe of Gansu Province

中文关键词:草原  高山草原  蝗虫  群落结构  生态位  多样性

keywords:grassland  alpine steppe  locust  community structure  ecological niche  diversity

中文摘要:为明确甘肃省不同草地类型的蝗虫群落结构及其空间生态位，对甘肃省永昌、山丹、肃南、天祝和夏河5个县的4种主要草地类型（低地草甸、高寒草甸、温性荒漠与山地草甸）的蝗虫种类及数量进行调查，并进行物种多样性、群落结构及空间生态位分析。结果显示：共采集蝗虫3 550头，隶属5科15属31种，其中常见种有12种，稀有种有16种，优势种有3种，分别为小翅雏蝗Chorthippusfallax、科氏痂蝗Bryodema kozlovi和亚洲小车蝗Oedaleus decorus asiaticus，占比分别为22.96%、18.85%和18.20%。在4种草原中，低地草甸分布有19种蝗虫，温性荒漠分布有17种，山地草甸均分布有16种，高寒草甸分布有15种，蝗虫群落多样性指数、丰富度指数和均匀度指数最高的是低地草甸，其次是温性荒漠与山地草甸，高寒草甸最低。高寒草甸与山地草甸、低地草甸与温性荒漠中蝗虫群落结构中等相似。在31种蝗虫中，生态位宽度位列前5位的依次是白纹雏蝗Ch.albonemus、狭翅雏蝗Ch.dubius、科氏痂蝗、宽须蚁蝗Myrmeleotettix palpalis和鼓翅皱膝蝗Angaracrisbarabensis，分别为0.758、0.667、0.633、0.582和0.559。在31种蝗虫中，只有6对蝗虫的生态位重叠指数大于0.30，其中鼓翅皱膝蝗对轮纹痂蝗Bryodema tuberculatum dilutum的重叠指数最高为0.34，其他均小于或者等于0.30。在31种蝗虫中，有5对蝗虫的空间生态位相似性最高，相似性系数为1.00，许多蝗虫种类的空间生态位无相似性，相似性系数为0。表明甘肃省4种主要草地类型的蝗虫群落结构和多样性存在差异。

Abstract:To explore the species diversity of locusts and grasshoppers in the alpine grasslands of Gansu Province, locust and grasshopper samples were collected from four habitats in Gansu Province. The study analyzed species diversity and spatial niche of locusts and grasshoppers. A total of 3 550 insects were collected belonging to five families, 15 genera and 31 species. Among them,three dominant species were identified: Chorthippus fallax, Bryodema kozlovi and Oedaleus decorus asiaticus, including 12 common species and 16 rare species. The diversity index, richness index and evenness index of locust and grasshopper community in lowland meadows (with 19 species) were significantly higher than those in other habitats, followed by temperate deserts and mountain meadows, with 17 and 16 species of locust and grasshopper species, respectively. Alpine meadow had the lowest diversity index, richness index, evenness index, but the highest dominance index, with 15 species recorded. Furthermore, the locust and grasshopper communities in alpine meadow and mountain meadows, as well as those in lowland meadows and temperate deserts, exhibited moderate similarity. According to niche width analysis of the 31 locust and grasshopper species, the top five were Ch. albonemus (0.758), Ch. dubius (0.667), Bryodema kozlovi (0.633), Myrmeleotettix palpalis (0.582), and Angaracris barabensis (0.559). Only six pairs of locust and grasshopper species had a niche overlap index greater than 0.30, with the highest overlap (0.34) obserbed Angaracris barabensis and Bryodema tuberculatum dilutum. All other pairs had a niche overlap index below all less than or equal to 0.30. The niche proportion similarity further reflected the niche overlap index, and only five pairs of locust and grasshopper species had the highest similarity coefficient of 1.00. Many locust and grasshopper species showed no spatial niche similarity. These results indicated that differences in locust and grasshopper community composition and diversity among the four main grassland types in Gansu Province.