Structures of arthropod communities involved in the grazing and detrital food webs and their functioning in a forest ecosystem

利用落叶袋对柳杉人工林乔木和土壤微生境中小节肢动物的定殖型进行了研究。随着土壤腐解度的增加，枯枝落叶质量在各枯落物袋中的变化显著增大，而在树体环境中变化较小。土壤微节肢动物由于凋落物分解速度较快而受演替变化的影响较大，而树栖微节肢动物由于分解过程较慢而受季节变化的影响较大。比较分析表明：(1)树冠中树栖蜘蛛群落的物种多样性受到树冠结构复杂性的影响，(2)日本竹林各层之间的树栖蜘蛛群落差异较大，这主要是由于资源质量(活叶或死叶)的差异；(3)两种林分林下蜘蛛群落组成因树种不同而异，主要是由于生境结构的复杂性所致。

The colonization patterns of microarthropods were examined in arboreal and soil microhabitats of a Cryptomeria japonica plantation by using litter bags. The variation in leaf-litter mass among litter bags increased markedly with increasing decomposition in the soil, and was smaller in the arboreal environment. Soil microarthropods were suggested to be more affected by successional changes because of faster decomposition of the litter, whereas arboreal microarthropods by seasonal changes because of slower decomposition processes.Comparative analyses revealed that(1) the species diversity of arboreal spider communities in canopies was influenced by the structural complexity of the foliage ;(2) arboreal spider communities differed more distinctly between the layers of the C. japonica than L. kaempferi canopy, mainly due to the difference in the resource quality(living or dead foliage);(3) the community composition of spiders on the forest floor differed between tree species as well as between the canopy and forest floor in both stands, primarily due to the structural complexity of habitats.