Composition of Soil Bacterial and Nematode Communities within Soil Aggregates in a Kiwifruit Orchard under Cover Crop Treatment

Soil, which exhibits difference in nutrient contents and aggregate sizes, provides spatially distinct habitats for biota. Cover crops influence the compositions of soil organism communities, playing an indispensable role regulation underground food webs ecosystem functions. However, effect cover on microbes nematodes distribution within different sizes remains unknown. Thus, a field experiment kiwifruit orchard with was conducted to estimate bacteria (mega-aggregate (>2 mm, LMA), macro-aggregate (0.25–2 SMA), micro-aggregate (<0.25 MA)) crop treatments (four species (CC) no as control (CK)). The results showed that bacterial varied both treatments. composition community significantly between mega-aggregate micro-aggregate, diversity higher compared mega-aggregate. Moreover, treatment dramatically changed communities. nematode communities were mainly impacted by sizes. Larger aggregates (mega- macro-aggregates) contained abundance omnivores/predators lower fungivores. In contrast community, richness micro-aggregates larger macro-aggregates). Redundancy analysis (RDA) structural equation model (SEM) organic carbon (SOC) main factor directly indirectly affected investigations could provide better understanding cycling across size fractions.