Promptの説明

Soil biodiversity in apple orchards plays a vital role for productivity but is seldom investigated for more than two organismal groups. We studied soil biodiversity of bacteria, protists, fungi, and invertebrates of 26 apple orchards in Northern-Italy by environmental DNA metabarcoding of the 16S and 18S ribosomal RNA, ITS, and COI marker genes. Chemical and biological parameters were assessed from the upper 20 cm during summer 2023. We used alpha- and beta-diversity, distance decay relationships, immigration rates and community assembly processes, variance partitioning between space and environment, and putative bacterial and fungal functions to get a holistic understanding on the drivers of soil communities. Bacteria and protists showed a higher immigration rate than the other two groups supporting the size-plasticity hypothesis. The generally low immigration rate for all groups was linked to the low number of taxa occurring in all sites. Soil communities were mainly assembled by stochastic processes, even though deterministic processes were also important. Turnover dominated community composition for all four organismal groups. Among putative bacterial functions, most were associated with carbon and nitrogen cycling. Our study provided mechanistic insights into the diversity of soil organisms of apple orchards belonging to different trophic levels.