Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 40, 6666 ZG Heteren, The Netherlands.
Ecology. 2010 Oct;91(10):3027-36. doi: 10.1890/09-2198.1.
Soils are extremely rich in biodiversity, and soil organisms play pivotal roles in supporting terrestrial life, but the role that individual plants and plant communities play in influencing the diversity and functioning of soil food webs remains highly debated. Plants, as primary producers and providers of resources to the soil food web, are of vital importance for the composition, structure, and functioning of soil communities. However, whether natural soil food webs that are completely open to immigration and emigration differ underneath individual plants remains unknown. In a biodiversity restoration experiment we first compared the soil nematode communities of 228 individual plants belonging to eight herbaceous species. We included grass, leguminous, and non-leguminous species. Each individual plant grew intermingled with other species, but all plant species had a different nematode community. Moreover, nematode communities were more similar when plant individuals were growing in the same as compared to different plant communities, and these effects were most apparent for the groups of bacterivorous, carnivorous, and omnivorous nematodes. Subsequently, we analyzed the composition, structure, and functioning of the complete soil food webs of 58 individual plants, belonging to two of the plant species, Lotus corniculatus (Fabaceae) and Plantago lanceolata (Plantaginaceae). We isolated and identified more than 150 taxa/groups of soil organisms. The soil community composition and structure of the entire food webs were influenced both by the species identity of the plant individual and the surrounding plant community. Unexpectedly, plant identity had the strongest effects on decomposing soil organisms, widely believed to be generalist feeders. In contrast, quantitative food web modeling showed that the composition of the plant community influenced nitrogen mineralization under individual plants, but that plant species identity did not affect nitrogen or carbon mineralization or food web stability. Hence, the composition and structure of entire soil food webs vary at the scale of individual plants and are strongly influenced by the species identity of the plant. However, the ecosystem functions these food webs provide are determined by the identity of the entire plant community.
土壤中蕴藏着极其丰富的生物多样性,土壤生物在维持陆地生命方面发挥着关键作用,但单个植物和植物群落在影响土壤食物网的多样性和功能方面所起的作用仍存在很大争议。植物作为初级生产者和土壤食物网的资源提供者,对土壤群落的组成、结构和功能至关重要。然而,个体植物下的完全开放于迁入和迁出的自然土壤食物网是否存在差异仍不得而知。在一项生物多样性恢复实验中,我们首先比较了 228 株 8 种草本植物个体的土壤线虫群落。这些植物包括禾本科、豆科和非豆科植物。每个个体植物与其他物种混生,但所有植物物种的线虫群落都不同。此外,当植物个体在相同的植物群落中生长时,其线虫群落更为相似,而当它们在不同的植物群落中生长时,这种相似性则较低,而这种影响在食细菌、食动物和杂食性线虫群体中最为明显。随后,我们分析了 58 株植物个体的完整土壤食物网的组成、结构和功能,这些植物个体隶属于两种植物,即百脉根(豆科)和车前草(车前科)。我们分离并鉴定了 150 多种土壤生物。整个食物网的土壤群落组成和结构既受到植物个体的物种身份的影响,也受到周围植物群落的影响。出乎意料的是,植物身份对分解土壤生物的影响最大,而这些生物通常被认为是广食性的。相比之下,定量食物网模型表明,植物群落的组成影响个体植物下的氮矿化,但植物物种身份不会影响氮或碳矿化或食物网稳定性。因此,整个土壤食物网的组成和结构在个体植物尺度上存在差异,并受到植物物种身份的强烈影响。然而,这些食物网提供的生态系统功能是由整个植物群落的身份决定的。