Netherlands Institute of Ecology (NIOO-KNAW), Department of Microbial Ecology, Wageningen, the Netherlands.
Wageningen University and Research Centre (WUR), Laboratory of Nematology, Wageningen, the Netherlands.
Sci Total Environ. 2019 Dec 10;695:133885. doi: 10.1016/j.scitotenv.2019.133885. Epub 2019 Aug 12.
Anthropogenic modification of soil systems has diverse impacts on food web interactions and ecosystem functioning. To understand the positive, neutral or adverse effects of agricultural practices on the associations of community members of soil microbes and microfaunal biomes, we characterized the effects of different fertilization types (organic, inorganic and a combination of organic and inorganic) on the food web active communities in the bulk soil and rhizosphere compartments in field conditions. We examined the influence of fertilization on (i) individual groups (bacteria, protozoa and fungi as microbe representatives and metazoans as microfauna representatives) and (ii) inter-kingdom interactions (focusing on the interactions between bacteria and eukaryotic groups) both neglecting and considering environmental factors in our analysis in combination with the microbial compositional data. Our results revealed different patterns of biota communities under organic versus inorganic fertilization, which shaped food web associations in both the bulk and rhizosphere compartments. Overall, organic fertilization increased the complexity of microbial-microfaunal ecological associations with inter- and intra- connections among categories of primary decomposers (bacteria and fungi) and predators (protozoa and microfauna) and differences in potential function in the soil food web in both the bulk and rhizosphere compartments. Furthermore, the inter-connections between primary decomposers and predators in bulk soil were more pronounced when environmental factors were considered. We suggest that organic fertilization selects bacterial orders with different potential ecological functions and interactions as survival, predation and cooperation due to more complex environment than those of inorganic or combined fertilization. Our findings support the importance of a comprehensive understanding of trophic food web patterns for soil management systems.
人为改变土壤系统对食物网相互作用和生态系统功能有多种影响。为了了解农业实践对土壤微生物和微区生物区系群落成员的关联的积极、中性或不利影响，我们在田间条件下，描述了不同施肥类型（有机、无机和有机与无机的组合）对土壤团聚体和根际区食物网活性群落的影响。我们研究了施肥对（i）个体群体（细菌、原生动物和真菌作为微生物代表，后生动物作为微区动物代表）和（ii）跨生物界相互作用（专注于细菌和真核生物组之间的相互作用）的影响，在分析中我们结合了微生物组成数据，同时忽略和考虑了环境因素。我们的结果表明，有机与无机施肥下的生物群落呈现出不同的模式，这些模式塑造了团聚体和根际区食物网的关联。总的来说，有机施肥增加了微生物-微区动物生态关联的复杂性，在团聚体和根际区中，初级分解者（细菌和真菌）和捕食者（原生动物和微区动物）的各分类群之间以及潜在功能之间都存在相互联系和差异。此外，当考虑环境因素时，在土壤团聚体中，初级分解者和捕食者之间的联系更为明显。我们认为，有机施肥由于环境比无机或组合施肥更复杂，因此选择了具有不同潜在生态功能和相互作用的细菌目，如生存、捕食和合作。我们的研究结果支持了全面了解土壤管理系统中营养食物网模式的重要性。
