Nematode consumption by mite communities varies in different forest microhabitats as indicated by molecular gut content analysis
Nematode consumption by mite communities varies in different forest microhabitats as indicated by molecular gut content analysis
复制标题
DOI：
10.1007/s10493-014-9807-x
复制
发表时间：
2014-09-01
影响因子：
2.2
通讯作者：
Maraun, Mark
中科院分区：
文献类型：
--
作者：
Heidemann, Kerstin;Ruess, Liliane;Maraun, Mark
土壤动物生活在复杂和异质性的生境中，包括各种类型的凋落物，也包括苔藓、真菌垫和草地等微生境。土壤食物网已被分为缓慢的真菌能量通道和快速的细菌能量通道。以细菌为食的线虫是细菌能量通道的重要组成部分，它们以细菌为食，形成土壤微节肢动物等营养水平较高的猎物。调查线虫作为高营养级消费者猎物的作用一直受到方法问题的阻碍，这些问题与线虫体型小和缺乏可在消费者肠道中追踪的骨骼结构有关。最近利用分子肠道内容分析的研究表明，线虫是土壤微节肢动物的主要猎物，包括那些以前被认为是食腐动物的动物。利用分子标记技术，在3种不同的微生境（凋落物、草地和苔藓）中，对14个丰富的土壤微节肢动物类群（均为蜱螨目）的线虫猎物进行了追踪。不同螨种对线虫的摄取量存在差异，说明落叶林中小节肢动物的多样性与营养生态位的变化有关。此外，在不同的微生境中，中鞭毛虫（而非甲鞭毛虫）对线虫的消耗不同，这表明营养生态位随生境特征而变化。总的来说，结果表明，自由生活的细菌喂养线虫是土壤微节肢动物的重要猎物，包括那些以前被认为是食腐动物的动物。
Soil animals live in complex and heterogeneous habitats including litter of various types but also microhabitats such as mosses, fungal mats and grass patches. Soil food webs have been separated into a slow fungal and a fast bacterial energy channel. Bacterial-feeding nematodes are an important component of the bacterial energy channel by consuming bacteria and forming prey for higher trophic levels such as soil microarthropods. Investigating the role of nematodes as prey for higher trophic level consumers has been hampered by methodological problems related to their small body size and lack in skeletal structures which can be traced in the gut of consumers. Recent studies using molecular gut content analyses suggest that nematodes form major prey of soil microarthropods including those previously assumed to live as detritivores. Using molecular markers we traced nematode prey in fourteen abundant soil microarthropod taxa of Mesostigmata and Oribatida (both Acari) from three different microhabitats (litter, grass and moss). Consumption of nematodes varied between mite species indicating that trophic niche variation contributes to the high diversity of microarthropods in deciduous forests. Further, consumption of nematodes by Mesostigmata (but not Oribatida) differed between microhabitats indicating that trophic niches vary with habitat characteristics. Overall, the results suggest that free-living bacterial-feeding nematodes form important prey for soil microarthropods including those previously assumed to live as detritivores.