One-Year Monitoring of Daily Earthworm Cast Production: Surface Cast Contribution to Soil Fertility in a Subtropical Forest

The process of earthworm casting plays an important role in soil fertility. contributions casts to nutrients dynamics cannot be fully understood unless the temporal changes cast production and related nutrient resource pools are explored field. Here, we recorded daily surface earthworms monthly change patterns carbon (C), nitrogen (N) phosphorous (P) a subtropical plantation for one year compared concentrations microbial community traits (structure bacterial activity) with those bulk soils. Our objectives were characterize C assess potential contribution results showed that annual at study site was 8.3 tons ha−1; >80 g m−2 during April November <30 December March. outputs total organic (TOC), N (TN) P (TP) 68.10, 4.84 0.38 m−2, respectively; available (AP), NH4+-N NO3−-N 22.4, 147.0 61.3 mg respectively. TOC TN higher warm months, but cold while both TP AP constant throughout year. 1.6–4.3-fold greater, biomass contents 7–8-fold greater than However, stress index (BSI) significantly soil, which implies bacteria under stress. Accordingly, ratio fungal (F/B) soil. Earthworm activity can forest into “new soil”, forms large amounts earthworm-induced hotspots These casts, fluctuated P, could more readily accessed by fungi rather bacteria. potentially interactions plants rhizosphere microbiota.