强还原土壤灭菌对土壤原生生物群落的影响OA北大核心CSTPCD

Reductive soil disinfestation(RSD)is an efficient,safe,and environment-friendly method for soil sterilization.Soil protozoa play a crucial role in promoting soil nutrient cycling and plant growth.Although many studies have focused on the effects of a strong reduction in soil sterilization on bacterial and fungal communities,little attention has been paid to protozoan communities.In this study,tomato soils with long-term continuous cropping were subjected to four different RSD treatments:control,treatment with added corn stalk,treatment with added bagasse,and treatment with both corn stalk and bagasse.The RSD process involved adding organic materials according to the specified treatments,isolating the air through flooding and film mulching,and maintaining the temperature at 35℃for 21 d.Soil samples were collected on the 1st,3rd,7th,and 21st days of natural air drying,and the 21st-day samples were selected for high-throughput 18S rRNA amplicon sequencing.The results revealed that different RSD treatments led to fluctuations in the soil total carbon and available phosphorus content during natural air drying.After RSD treatment,Cercozoa,Cilipohora,and Amoebozoa were the dominant protozoan groups,with relative abundances ranging from 19.2%to 25.9%,13.8%to 26.9%,and 12.0%to 28.8%,respectively.RSD treatment increased the relative abundance of predatory and parasitic protozoan communities while decreasing the relative abundance of autotrophic protozoa.However,it did not significantly improve the overall diversity of the soil protozoan communities.Soil available phosphorus and ammonium nitrogen contents have emerged as key environmental factors influencing soil protozoan communities.Notably,the available soil phosphorus content was significantly correlated with the relative abundance of predator,autotrophic,and parasitic protozoan functional communities.This study underscores the significant impact of RSD treatment on the composition and function of protozoan communities in the soil.