Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulato...Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulator remain poorly understood.In this study,we examine the collaborative influences of soil physicochemical properties(i.e.,soil water,soil organic matter(SOM),salinity,total phosphorus and nitrogen,pH,soil bulk density and fine root biomass)and soil microorganisms(fungi and bacteria)on plant diversity across two types of tree patches dominated by big and small trees(big trees:height≥7 m and DBH≥60 cm;small trees:height≤4.5 m and DBH≤20 cm)in an arid desert region.Tree patch is consists of a single tree or group of trees and their accompanying shrubs and herbs.It was hypothesized that soil physicochemical properties and microorganisms affect plant diversity but their influence differ.The results show that plant and soil microbial diversity increased with increasing distances from big trees.SOM,salinity,fine root biomass,soil water,total phosphorus and total nitrogen contents decreased with increasing distance from big trees,while pH and soil bulk density did not change.Plant and soil microbial diversity were higher in areas close to big trees compared with small trees,whereas soil physicochemical properties were opposite.The average contribution of soil physicochemical properties(12.2%-13.5%)to plant diversity was higher than microbial diversity(4.8%-6.7%).Salinity had the largest negative affect on plant diversity(24.7%-27.4%).This study suggests that soil fungi constrain plant diversity while bacteria improve it in tree patches.Soil physicochemical properties are the most important factor modulating plant diversity in arid desert tree patches.展开更多
Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determi...Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators(e.g.,soil microbial diversity,stand structure,and environmental conditions)remains uncertain.In this study,effects of aboveground(species richness and functional and structural diversity)and belowground(bacterial and fungal diversity)biodiversity,functional composition(community-weighted means of species traits),stand structure(diameter at breast height and stand density),and soil factors(pH and bulk density)on multifunctionality(including biomass production,carbon stock,and nutrient cycling)were examined along a tree diversity gradient in subtropical forests.The community-weighted mean of tree maximum height was the best predictor of ecosystem multifunctionality.Functional diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal diversity.Stand structure-played an important role in modulating the effects of tree diversity on multifunctionality.The work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes.展开更多
Rural domestic reclaimed water(RDRW)is rural domestic sewage that being safely treated,the irrigation and reuse of RDRW are an effective way to alleviate the contradiction between supply and demand of water resources ...Rural domestic reclaimed water(RDRW)is rural domestic sewage that being safely treated,the irrigation and reuse of RDRW are an effective way to alleviate the contradiction between supply and demand of water resources in South China.In this study,four kinds of irrigation water sources(primary and secondary treated water R1 and R2,purified water R3 and river water CK)and three kinds of water level regulations(low,medium,and high field water level control of W1,W2 and W3)were set to study the impact of RDRW on soil and crop safety,water and nitrogen utilization and biodiversity for establishing the regulation mechanism of RDRW irrigation with field experiment,and monitoring was carried out in RDRW irrigation demonstration area to assess the effectiveness of RDRW.The results showed that,under RDRW irrigation,the contents of Cd and Pb increased slightly,while the contents of Cr,Cu and Zn decreased in paddy soil.The heavy metals content decreased along the direction of stem,leaf and grain in rice plants,but did not increase significantly in rice grains.With the increase of field water level,pharmaceutical and personal care products(PPCPs)content in 60-80 cm soil layer was accumulated,and the PPCPs content in rice husks was higher than that in grains,but it was at a very low level.Compared to CK,RDRW irrigation can effectively increase rice yield,rainwater use efficiency(RUE)and nitrogen use efficiency(NUE)by 5.4%-7.6%,6.7%-9.4%and 21.7%-24.2%,respectively,and the species diversity,community diversity and richness in rice fields were improved.Additionally,water level regulation of W3 with R2 water resource irrigation was conducive to the exertion of comprehensive benefits.The monitoring of demonstration area showed that the consumption of fresh water was reduced by 530 mm,yield was increased by 9.6%,and the soil and crop were both safety.Short-term irrigation of RDRW did not cause soil and crops pollution,however,it is still necessary to track and monitor the effect of the system on soil,crop,and underground water with long-term reclaimed water irrigation.展开更多
Soil microbial carbon metabolism is critical in wetland soil carbon cycling,and is also a research hotspot at present.However,most studies focus on the surface soil layer in the wetlands and the microorganisms associa...Soil microbial carbon metabolism is critical in wetland soil carbon cycling,and is also a research hotspot at present.However,most studies focus on the surface soil layer in the wetlands and the microorganisms associated with this layer.In this study,0-75 cm soil profiles were collected from five widely separated reed wetlands in the Songnen Plain,which has a large number of middle-high latitude inland saline-sodic wetlands.The Biolog-ECO method was used to determine the carbon metabolic activity and functional diversity of soil microorganisms.The results showed that soil carbon metabolic activity decreased with increasing soil depth.The carbon metabolic activity of soil microorganisms in the 60-75 cm layer was approximately 57.41%-74.60%of that in the 0-15 cm layer.The soil microbial Shannon index and utilization rate of amines decreased with an increase in soil depth,while the Evenness index and utilization rate of polymers tended to increase with soil depth.Dissolved organic carbon(DOC)is the most important factor affecting microbial carbon source utilization preference,because microorganisms mainly obtain the carbon source from DOC.The result of the correlation analysis showed that the soil microbial carbon metabolic activity,Shannon index,and Evenness index significantly correlated with soil total carbon(TC),microbial biomass carbon(MBC),DOC,total nitrogen(TN),ammonium nitrogen(NH_(4)^(+)-N),nitrate nitrogen(NO_(3)_(−)-N)contents,and electrical conductivity(EC).This study emphasized the important role of microbial carbon metabolic function in deep soil.展开更多
Climate warming may promote soil organic carbon(SOC)decomposition and alter SOC stocks in terrestrial ecosystems,which would in turn affect climate warming.We manipulated a warming experiment using open-top chambers t...Climate warming may promote soil organic carbon(SOC)decomposition and alter SOC stocks in terrestrial ecosystems,which would in turn affect climate warming.We manipulated a warming experiment using open-top chambers to investigate the effect of warming on SOC stock and chemical composition in an alpine peatland in Zoigêon the eastern Tibetan Plateau,China.Results showed that 5 years of warming soil temperatures enhanced ecosystem respiration during the growing season,promoted above-and belowground plant biomass,but did not alter the SOC stock.However,labile O-alkyl C and relatively recalcitrant aromatic C contents decreased,and alkyl C content increased.Warming also increased the amount of SOC stored in the silt-clay fraction(<0.053 mm),but this was offset by warming-induced decreases in the SOC stored within micro-and macroaggregates(0.053–0.25 and>0.25 mm,respectively).These changes in labile and recalcitrant C were largely associated with warming-induced increases in soil microbial biomass C,fungal diversity,enzyme activity,and functional gene abundance related to the decomposition of labile and recalcitrant C compounds.The warming-induced accumulation of SOC stored in the silt-clay fraction could increase SOC persistence in alpine peatland ecosystems.Our findings suggest that mechanisms mediated by soil microbes account for the changes in SOC chemical composition and SOC in different aggregate size fractions,which is of great significance when evaluating SOC stability under climate warming conditions.展开更多
基金This work was supported fi nancially by National Natural Science Foundation of China(Grant Nos.and 41,871,031 and 31,860,111)Natural Science Foundation of Xinjiang(Grant No.2017D01C080).
文摘Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulator remain poorly understood.In this study,we examine the collaborative influences of soil physicochemical properties(i.e.,soil water,soil organic matter(SOM),salinity,total phosphorus and nitrogen,pH,soil bulk density and fine root biomass)and soil microorganisms(fungi and bacteria)on plant diversity across two types of tree patches dominated by big and small trees(big trees:height≥7 m and DBH≥60 cm;small trees:height≤4.5 m and DBH≤20 cm)in an arid desert region.Tree patch is consists of a single tree or group of trees and their accompanying shrubs and herbs.It was hypothesized that soil physicochemical properties and microorganisms affect plant diversity but their influence differ.The results show that plant and soil microbial diversity increased with increasing distances from big trees.SOM,salinity,fine root biomass,soil water,total phosphorus and total nitrogen contents decreased with increasing distance from big trees,while pH and soil bulk density did not change.Plant and soil microbial diversity were higher in areas close to big trees compared with small trees,whereas soil physicochemical properties were opposite.The average contribution of soil physicochemical properties(12.2%-13.5%)to plant diversity was higher than microbial diversity(4.8%-6.7%).Salinity had the largest negative affect on plant diversity(24.7%-27.4%).This study suggests that soil fungi constrain plant diversity while bacteria improve it in tree patches.Soil physicochemical properties are the most important factor modulating plant diversity in arid desert tree patches.
基金financially supported by the National Natural Science Foundation of China(Nos.32071561 and 31870431)the Science and Technology Innovation Program of Hunan Province(No.2021RC3104)+1 种基金the Research Foundation of the Education Bureau of Hunan Province(No.19B586)the Huitong Forest Ecological Station Funds provided by the State Forestry and Grass Administration of China(No.2021132078)。
文摘Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators(e.g.,soil microbial diversity,stand structure,and environmental conditions)remains uncertain.In this study,effects of aboveground(species richness and functional and structural diversity)and belowground(bacterial and fungal diversity)biodiversity,functional composition(community-weighted means of species traits),stand structure(diameter at breast height and stand density),and soil factors(pH and bulk density)on multifunctionality(including biomass production,carbon stock,and nutrient cycling)were examined along a tree diversity gradient in subtropical forests.The community-weighted mean of tree maximum height was the best predictor of ecosystem multifunctionality.Functional diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal diversity.Stand structure-played an important role in modulating the effects of tree diversity on multifunctionality.The work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes.
基金supported by National Key Research and Development Program(2019YFC0408803)Basic Public Welfare Research Project of Zhejiang Province(LGN20E090001)and Water conservancy science and technology in Zhejiang Province(RC1918,RC2029).
文摘Rural domestic reclaimed water(RDRW)is rural domestic sewage that being safely treated,the irrigation and reuse of RDRW are an effective way to alleviate the contradiction between supply and demand of water resources in South China.In this study,four kinds of irrigation water sources(primary and secondary treated water R1 and R2,purified water R3 and river water CK)and three kinds of water level regulations(low,medium,and high field water level control of W1,W2 and W3)were set to study the impact of RDRW on soil and crop safety,water and nitrogen utilization and biodiversity for establishing the regulation mechanism of RDRW irrigation with field experiment,and monitoring was carried out in RDRW irrigation demonstration area to assess the effectiveness of RDRW.The results showed that,under RDRW irrigation,the contents of Cd and Pb increased slightly,while the contents of Cr,Cu and Zn decreased in paddy soil.The heavy metals content decreased along the direction of stem,leaf and grain in rice plants,but did not increase significantly in rice grains.With the increase of field water level,pharmaceutical and personal care products(PPCPs)content in 60-80 cm soil layer was accumulated,and the PPCPs content in rice husks was higher than that in grains,but it was at a very low level.Compared to CK,RDRW irrigation can effectively increase rice yield,rainwater use efficiency(RUE)and nitrogen use efficiency(NUE)by 5.4%-7.6%,6.7%-9.4%and 21.7%-24.2%,respectively,and the species diversity,community diversity and richness in rice fields were improved.Additionally,water level regulation of W3 with R2 water resource irrigation was conducive to the exertion of comprehensive benefits.The monitoring of demonstration area showed that the consumption of fresh water was reduced by 530 mm,yield was increased by 9.6%,and the soil and crop were both safety.Short-term irrigation of RDRW did not cause soil and crops pollution,however,it is still necessary to track and monitor the effect of the system on soil,crop,and underground water with long-term reclaimed water irrigation.
基金the Jilin Scientific and Technological Development Program(20210101091JC)the National Natural Science Foundation of China(41730643,41871090)the Innovation Team Project of Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences(2022CXTD02).
文摘Soil microbial carbon metabolism is critical in wetland soil carbon cycling,and is also a research hotspot at present.However,most studies focus on the surface soil layer in the wetlands and the microorganisms associated with this layer.In this study,0-75 cm soil profiles were collected from five widely separated reed wetlands in the Songnen Plain,which has a large number of middle-high latitude inland saline-sodic wetlands.The Biolog-ECO method was used to determine the carbon metabolic activity and functional diversity of soil microorganisms.The results showed that soil carbon metabolic activity decreased with increasing soil depth.The carbon metabolic activity of soil microorganisms in the 60-75 cm layer was approximately 57.41%-74.60%of that in the 0-15 cm layer.The soil microbial Shannon index and utilization rate of amines decreased with an increase in soil depth,while the Evenness index and utilization rate of polymers tended to increase with soil depth.Dissolved organic carbon(DOC)is the most important factor affecting microbial carbon source utilization preference,because microorganisms mainly obtain the carbon source from DOC.The result of the correlation analysis showed that the soil microbial carbon metabolic activity,Shannon index,and Evenness index significantly correlated with soil total carbon(TC),microbial biomass carbon(MBC),DOC,total nitrogen(TN),ammonium nitrogen(NH_(4)^(+)-N),nitrate nitrogen(NO_(3)_(−)-N)contents,and electrical conductivity(EC).This study emphasized the important role of microbial carbon metabolic function in deep soil.
基金supported by the National Natural Science Foundation of China(Nos.41971024 and 41373069)。
文摘Climate warming may promote soil organic carbon(SOC)decomposition and alter SOC stocks in terrestrial ecosystems,which would in turn affect climate warming.We manipulated a warming experiment using open-top chambers to investigate the effect of warming on SOC stock and chemical composition in an alpine peatland in Zoigêon the eastern Tibetan Plateau,China.Results showed that 5 years of warming soil temperatures enhanced ecosystem respiration during the growing season,promoted above-and belowground plant biomass,but did not alter the SOC stock.However,labile O-alkyl C and relatively recalcitrant aromatic C contents decreased,and alkyl C content increased.Warming also increased the amount of SOC stored in the silt-clay fraction(<0.053 mm),but this was offset by warming-induced decreases in the SOC stored within micro-and macroaggregates(0.053–0.25 and>0.25 mm,respectively).These changes in labile and recalcitrant C were largely associated with warming-induced increases in soil microbial biomass C,fungal diversity,enzyme activity,and functional gene abundance related to the decomposition of labile and recalcitrant C compounds.The warming-induced accumulation of SOC stored in the silt-clay fraction could increase SOC persistence in alpine peatland ecosystems.Our findings suggest that mechanisms mediated by soil microbes account for the changes in SOC chemical composition and SOC in different aggregate size fractions,which is of great significance when evaluating SOC stability under climate warming conditions.