Microorganisms regulate the responses of terrestrial ecosystems to anthropogenic nutrient inputs.The escalation of anthropogenic activities has resulted in a rise in the primary terrestrial constraining elements,namel...Microorganisms regulate the responses of terrestrial ecosystems to anthropogenic nutrient inputs.The escalation of anthropogenic activities has resulted in a rise in the primary terrestrial constraining elements,namely nitrogen(N)and phosphorus(P).Nevertheless,the specific mechanisms governing the influence of soil microbial community structure and ecological processes in ecologically vulnerable and delicate semi-arid loess agroecosystems remain inadequately understood.Therefore,we explored the effects of different N and P additions on soil microbial community structure and its associated ecological processes in the farmland of Chinese Loess Plateau based on a 36-a long-term experiment.Nine fertilization treatments with complete interactions of high,medium,and low N and P gradients were set up.Soil physical and chemical properties,along with the microbial community structure were measured in this study.Additionally,relevant ecological processes such as microbial biomass,respiration,N mineralization,and enzyme activity were quantified.To elucidate the relationships between these variables,we examined correlation-mediated processes using statistical techniques,including redundancy analysis(RDA)and structural equation modeling(SEM).The results showed that the addition of N alone had a detrimental effect on soil microbial biomass,mineralized N accumulation,andβ-1,4-glucosidase activity.Conversely,the addition of P exhibited an opposing effect,leading to positive influences on these soil parameters.The interactive addition of N and P significantly changed the microbial community structure,increasing microbial activity(microbial biomass and soil respiration),but decreasing the accumulation of mineralized N.Among them,N24P12 treatment showed the greatest increase in the soil nutrient content and respiration.N12P12 treatment increased the overall enzyme activity and total phospholipid fatty acid(PLFA)content by 70.93%.N and P nutrient contents of the soil dominate the microbial community structure and the corresponding changes in hydrolytic enzymes.Soil microbial biomass,respiration,and overall enzyme activity are driven by mineralized N.Our study provides a theoretical basis for exploring energy conversion processes of soil microbial community and environmental sustainability under long-term N and P additions in semi-arid loess areas.展开更多
土壤环境是地球环境的重要组成部分。目前土壤环境问题的关注重点在于土壤污染。我国土壤污染以无机污染为主。中国生态系统研究网络(Chinese Ecosystem Research Network,CERN)自1988年组建以来,在中国主要农田、森林、草原、荒漠、湿...土壤环境是地球环境的重要组成部分。目前土壤环境问题的关注重点在于土壤污染。我国土壤污染以无机污染为主。中国生态系统研究网络(Chinese Ecosystem Research Network,CERN)自1988年组建以来,在中国主要农田、森林、草原、荒漠、湿地生态系统中,按统一的规范,对与土壤环境状况有关的铁、锰、铜、锌、硼、钼、镉、铬、铅、镍、汞、砷、硒元素进行了长期定位监测。通过对CERN典型生态样地表层土壤环境元素监测数据进行加工处理,获得1995~2011年中国陆地生态系统土壤环境元素含量数据集。本数据集中13种土壤环境元素指标测定的相对误差平均为6.55%,重复测定的相对偏差为7.70%。同时附有完整的背景信息,保证了数据在空间和时间上的一致性。本数据集可以为全国和区域土壤环境质量评估、土壤污染风险评价以及环境土壤学研究等工作提供数据基础。展开更多
基金funded by the Project of Science and Technology Department of Shaanxi Province,China(2022NY-074)the National Natural Science Foundation of China(41501255)+1 种基金the Xi'an Science and Technology Project(21NYYF0033)the Fundamental Research Funds for the Central Universities(SYJS202224,GK202206032).
文摘Microorganisms regulate the responses of terrestrial ecosystems to anthropogenic nutrient inputs.The escalation of anthropogenic activities has resulted in a rise in the primary terrestrial constraining elements,namely nitrogen(N)and phosphorus(P).Nevertheless,the specific mechanisms governing the influence of soil microbial community structure and ecological processes in ecologically vulnerable and delicate semi-arid loess agroecosystems remain inadequately understood.Therefore,we explored the effects of different N and P additions on soil microbial community structure and its associated ecological processes in the farmland of Chinese Loess Plateau based on a 36-a long-term experiment.Nine fertilization treatments with complete interactions of high,medium,and low N and P gradients were set up.Soil physical and chemical properties,along with the microbial community structure were measured in this study.Additionally,relevant ecological processes such as microbial biomass,respiration,N mineralization,and enzyme activity were quantified.To elucidate the relationships between these variables,we examined correlation-mediated processes using statistical techniques,including redundancy analysis(RDA)and structural equation modeling(SEM).The results showed that the addition of N alone had a detrimental effect on soil microbial biomass,mineralized N accumulation,andβ-1,4-glucosidase activity.Conversely,the addition of P exhibited an opposing effect,leading to positive influences on these soil parameters.The interactive addition of N and P significantly changed the microbial community structure,increasing microbial activity(microbial biomass and soil respiration),but decreasing the accumulation of mineralized N.Among them,N24P12 treatment showed the greatest increase in the soil nutrient content and respiration.N12P12 treatment increased the overall enzyme activity and total phospholipid fatty acid(PLFA)content by 70.93%.N and P nutrient contents of the soil dominate the microbial community structure and the corresponding changes in hydrolytic enzymes.Soil microbial biomass,respiration,and overall enzyme activity are driven by mineralized N.Our study provides a theoretical basis for exploring energy conversion processes of soil microbial community and environmental sustainability under long-term N and P additions in semi-arid loess areas.
文摘土壤环境是地球环境的重要组成部分。目前土壤环境问题的关注重点在于土壤污染。我国土壤污染以无机污染为主。中国生态系统研究网络(Chinese Ecosystem Research Network,CERN)自1988年组建以来,在中国主要农田、森林、草原、荒漠、湿地生态系统中,按统一的规范,对与土壤环境状况有关的铁、锰、铜、锌、硼、钼、镉、铬、铅、镍、汞、砷、硒元素进行了长期定位监测。通过对CERN典型生态样地表层土壤环境元素监测数据进行加工处理,获得1995~2011年中国陆地生态系统土壤环境元素含量数据集。本数据集中13种土壤环境元素指标测定的相对误差平均为6.55%,重复测定的相对偏差为7.70%。同时附有完整的背景信息,保证了数据在空间和时间上的一致性。本数据集可以为全国和区域土壤环境质量评估、土壤污染风险评价以及环境土壤学研究等工作提供数据基础。