Studies On Distribution, Community Structure And Sexual Selection Of Orthopterans In Aishan Natural Reserve On The East Of Shandong Province

Aishan Natural Reserve came into existence in 2001 and it needs basal research. From July to October, 2002, orthopterans of Aishan Natural Reserve were surveyed. With sampling methods, orthopterans were caught in different habitats such as woodlands, bush-grass lands, grasslands, bare lands and barren slops, roadside grass, banks and shores, farmlands, orchards and residential areas by trap, hand, light, food and struck. The quantity of species and distribution of orthopterans were investigated and recorded.Altogether there are 52 species and subspecies of orthopterans in Aishan Natural Reserve. These species belong to 40 genera, 16 families and 6 superfamilies, including 1 new record of species (Deracantha onos) to Shandong distribution knowledge. In Ensifera, 2 species belong to Gryllotalpoidea, 9 to Grylloidea, 10 to Tettigonioidea, 1 to Rhaphidophoridae. In Caelifera, 27 species belong to Acridoidea, 3 to Tetrigoidea. As to the compositions of fauna, polytopic species are much more than palaearctic realm species and oriental realm species and oriental realm species are least. Most species belong to the palaearctie realm species which have great abilities to adapt to their environments. The phenomenon of dominant families of orthopterans is very prominent in Aishan Natural Reserve, but most genera only include an and dominant genera aren't evident. Dominantfamilies of orthopterans include Catantopidae and Oedipodidae.The distribution of orthopterans is obviously correlate with habitats. All habitats of orthopterans can be divided into six habitat forms. In grassland-farm habitat form and banks and shores habitat form orthopterans are tend to the outbreak of population, so the two habitat forms should be monitored.The community of orthopterans has vertical stratification. Different orthopterans live in different vegetation strata because of their distinctions in temperature, humidity, rest and food supply. They are various in compoents and quantities. Different orthopterans live in different range of altitude because of the difference of vegetation and terrain. There are more orthopterans in low brae belt than in piedmont.The competition for mate of orthopterans is usually very intense, so the founction of sexual selection is specially powerful. The females of katydids select males to mate by the songs of males, however, the males of grasshoppers find females to mate by sex pheromones. Their postures of mate are prominently different.