摘要
[目的]通过探究长期"化肥有机替代"对土壤腐解微食物网复杂性和稳定性的影响,为土壤可持续培肥管理提供理论依据.[方法]依托南方红壤长期施肥田间定位试验,利用高通量测序技术研究土壤腐解微食物网生物群落组成和多样性对长期化肥有机替代的响应,并通过共现网络分析方法评价长期化肥有机替代对土壤腐解微食物网生态网络复杂性和稳定性的影响.[结果]长期化肥有机替代显著改变了土壤细菌、真菌、原生动物及整体微食物网的物种群落组成,并显著提高土壤细菌、真菌、原生动物、线虫及整体微食物网生物群落的物种丰富度.各功能群生态网络的平均度、平均聚类系数、连通性和模块化程度等绝大多数拓扑参数均表现为化肥有机替代处理下较高;与常规施肥处理相比,化肥有机替代处理各功能群生态网络的鲁棒性较高,细菌、原生动物、线虫和整体微食物网生态网络的脆弱性较低.[结论]长期化肥有机替代提高了南方红壤细菌、真菌、原生动物、线虫及整体微食物网生物群落的物种多样性,并提升了微食物网的生态网络复杂性和稳定性,对土壤生态功能有着潜在的改善作用.
Abstract
[Objective]This paper investigated the effects of organic substitution of mineral fertilizer(called organic substitution)on the complexity and stability of soil detritus micro-food web,aiming to provide a scientific basis for sustainable soil nutrient management.[Method]Based on a long-term field experiment in the red soil region of southern China,the response of community composition and diversity of soil detritus micro-food web to long-term organic substitution was examined by using high-throughput sequencing technology,and the effect of long-term organic substitution on ecological network complexity and stability of soil detritus micro-food web was evaluated by co-occurrence network analysis.[Result]The long-term organic substitution significantly altered the community composition of soil bacteria,fungi,protozoa,and the overall micro-food web,and increased species richness of soil bacteria,fungi,protozoa,nematodes,and the overall microbiota community of the micro-food web.Most topological parameters such as average degree,average clustering coefficient,connectivity and modularity of ecological network of each functional group showed higher under the organic substitution.The robustness of ecological network of each functional group was higher and the vulnerability of ecological network of bacteria,protozoa,nematodes and the overall micro-food web was lower under the organic substitution,compared to conventional fertilization treatment.[Conclusion]The results showed that long-term organic substitution increased the species diversity of soil bacteria,fungi,protozoa,nematodes and the overall community of the micro-food web,and enhanced ecological network complexity and stability of the micro-food web,which would potentially improve soil functioning.
基金项目
国家重点研发计划(2018YFD0800902)
广西自然科学基金(2021GXNSFAA220039)
广西自然科学基金(2022AC21309)
NETL
NSTL
万方数据