九华山土壤甲虫的生态分布

THE ECOLOGICAL DISTRIBUTION OF SOIL BEETLE IN JIUHUA MOUNTAINS

１９８８年４月—１９９２年１２月先后８次对九华山４种生境的土壤甲虫进行了调查，共获标本４１７头，隶属３３科。其中幼虫１５科；成虫２８科６４种（属）。平均密度７０５头／ｍ３。不同生境土壤甲虫群落组成的差异较大，仅分布于一种生境的种属多，共有的少。群落组成的丰富度（Ｓ）、均匀度（Ｅ）和香农指数值（Ｈ）均以灌丛草甸和混交林内高，黄山松林和马尾松林低，优势度指数值（Ｃ）正好相反。组成和数量的季节变化表现为冬季＞秋季＞春季＞夏季。幼虫个体数一般是成虫的２倍。垂直结构明显，Ａ层（０—５ｃｍ土壤深度）个体数占全捕量５６．８％，向下骤减。夏季表聚性强，占６７．５％，春季最小，占３８．３％。

From April, 1988 to December, 1992, 8 investigations on soil beetles are conducted under the vegetations of Pinus massoniana,laurilignosa and aestilignosa, Pinus taiwanensis and shrub-meadow of Jiuhua Mountains respectivcly.417 specimens were collectd, which belong to 33 families. Among them, 220 individuals are larvas, which belong to 15 families; 197 individuals are adults, which belong to 28 families, 64 species (genera).The average density is 705 individuals/m3. Melolonthidae(L) and Elateridae(L)are dominant genera. 18 kinds are common genera, which belong to Curculionidae(L), Staphylinidae(L), Platystethus operosus (A) and Longitasus succinens (A), etc.With increase of elevation, the habitat condition emerges vertical changes obviously,which results in the difference on the community structure of soil beetles. The richness,evenness and domiance indexes of community composition are all higher under the vegetations of mixed forest and shrub-meadow, than those under the vegetations of Pinustaiwanensis and Pinus inassoniana; the difference is considerable among each community composition, Jaccard similarity index is small. Species (genera) which appears in only one habitat are more, but the common species (genus) are fewer. Changes of individual number are not totally identical with genera number. The density of soil beetles under the vegetation of Pinus taiwanensis is higest, which is 1083.2 individuals/m3 averagely,however, the density under Pinus massoniana is lowest, which is 652.8/m3, But the seasonal changes of number in each habitat are different,the number under Pinus taiwanensis is more only in winter,and fewer in other seasons;numbers under shrub-meadow and mixed forest are steadier.As regards seasonal changes of species(genera) number and individual number of soil beetles, the general trend is winter>artumn>spring>summer.The individual number of larva is 2 times more than adult’s.but the individual number of adult's is 2.5 times more than larvat's in mixed forest.The law of vertical distribution of soil beetles in soil bed is obvious,that is,many genera and individuals centralize in A layer, and obviously decreasing downwards.Individual numbers in A layer constitute 56.8% averagely. This is not same in four seasons, the individual number of A layer is the most in summer, constitutes 67.5%; in spring is lowest, constitutes 38.3%. Families which mainly distribute in A layer are Staphylinidae(A),Curculionidae(A),Chrysomelidae(A),Leiodidae(A),Tenebrionidae(A), Monommatidae(A),Scaphidiidae,Silphidae (L) etc. Genera which only distribute in D layer are very few, only Dermestidae (A) and Hydrophilidae (L).