Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant uptake.However,the effect of N deposition on the flexibility of carbon(C),N,and...Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant uptake.However,the effect of N deposition on the flexibility of carbon(C),N,and phosphorus(P)in forest plant-soil-microbe systems remains unclear.Methods:We conducted a meta-analysis based on 751 pairs of observations to evaluate the responses of plant,soil and microbial biomass C,N and P nutrients and stoichiometry to N addition in different N intensity(050,50–100,>100 kg·ha^(-1)·year^(-1)of N),duration(0–5,>5 year),method(understory,canopy),and matter(ammonium N,nitrate N,organic N,mixed N).Results:N addition significantly increased plant N:P(leaf:14.98%,root:13.29%),plant C:P(leaf:6.8%,root:25.44%),soil N:P(13.94%),soil C:P(10.86%),microbial biomass N:P(23.58%),microbial biomass C:P(12.62%),but reduced plant C:N(leaf:6.49%,root:9.02%).Furthermore,plant C:N:P stoichiometry changed significantly under short-term N inputs,while soil and microorganisms changed drastically under high N addition.Canopy N addition primarily affected plant C:N:P stoichiometry through altering plant N content,while understory N inputs altered more by influencing soil C and P content.Organic N significantly influenced plant and soil C:N and C:P,while ammonia N changed plant N:P.Plant C:P and soil C:N were strongly correlated with mean annual precipitation(MAT),and the C:N:P stoichiometric flexibility in soil and plant under N addition connected with soil depth.Besides,N addition decoupled the correlations between soil microorganisms and the plant.Conclusions:N addition significantly increased the C:P and N:P in soil,plant,and microbial biomass,reducing plant C:N,and aggravated forest P limitations.Significantly,these impacts were contingent on climate types,soil layers,and N input forms.The findings enhance our comprehension of the plant-soil system nutrient cycling mechanisms in forest ecosystems and plant strategy responses to N deposition.展开更多
Research on the multicomponent synergistic relationships between plants,litter,and soil from the perspective of ecological stoichiometry helps to understand nutrient cycling and distribution mechanisms within ecosyste...Research on the multicomponent synergistic relationships between plants,litter,and soil from the perspective of ecological stoichiometry helps to understand nutrient cycling and distribution mechanisms within ecosystems.This study focused on Juniperus saltuaria,the dominant tree species in the forestline ecotone of Sygera Mountains,southeastern Xizang,China.We systematically measured and analyzed the Carbon(C),nitrogen(N),and phosphorus(P)contents and their relationships in plants(leaves,branches,trunks,fine roots),litter(undecomposed layer,partially decomposed layer,fully decomposed layer),and soil(0-10 cm,10-20 cm,20-40 cm)at different slope positions.The results showed significant differences in the C,N,and P contents and stoichiometry of plants and soil at different slope positions,while no significant differences were observed among litter layers.At the same slope position,the C,N,and P contents in leaves and surface soil were the highest,with soil nutrients significantly decreasing with increasing depth.For litter,the C content in the undecomposed layer was significantly higher than that in the partially and fully decomposed layers while the P content showed the opposite trend.Surface soil(0-20 cm)exhibited a decoupled relationship with plants but a coupled relationship with litter while deep soil(20-40 cm)showed a coupled relationship with plants.J.saltuaria showed faster growth rates on uphill slope.In this study area,J.saltuaria exhibited consistent trends of N,P,and N:P ratios homeostasis across different slope positions and organs,with leaves and fine roots both limited by N.Significant interactive effects between plants,litter,and soil nutrients were observed across different slope positions.Positive correlations were found between leaf and litter,and between fine root and leaf while the relationships between litter and soil,and between soil and fine root,varied.This study helps improve our understanding of the nutrient interactions between plants,litter,and soil in dominant species of alpine forest ecosystems,as well as their ecological adaptation mechanisms.展开更多
Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this s...Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this study,we examined the re-sponses of soil C,N,and P contents and their stoichiometric ratios to vegetation restoration age,focusing on below-ground processes and their relationships to aboveground vegetation community characteristics.We conducted an analysis of temporal gradients based on the'space for time'method to synthesize the effects of restoration age on soil C:N:P stoichiometry in the Yellow River Delta wetland of China.The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C:N:P stoichiometry.Specifically,restoration age significantly increased all topsoil C:N:P stoichiometries,except for soil total phosphorus(TP)and the C:N ratio,and slightly affected subsoil C:N:P stoichiometry.The effects of restoration age on the soil C:N ratio was well constrained owing to the coupled relationship between soil organic carbon(SOC)and total nitrogen(TN)contents,while soil TP con-tent was closely related to changes in plant species diversity.Importantly,we found that the topsoil C:N:P stoichiometry was signific-antly affected by plant species diversity,whereas the subsoil C:N:P stoichiometry was more easily regulated by pH and electric con-ductivity(EC).Overall,this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation,which is useful for further assessing soil C:N:P stoichiometry in coastal restoration wetlands.展开更多
Background:Large-scale afforestation can significantly change the ground cover and soil physicochemical properties,especially the soil fertility maintenance and water conservation functions of artificial forests,which...Background:Large-scale afforestation can significantly change the ground cover and soil physicochemical properties,especially the soil fertility maintenance and water conservation functions of artificial forests,which are very important in semi-arid mountain ecosystems.However,how different tree species affect soil nutrients and soil physicochemical properties after afforestation,and which is the best plantation species for improving soil fertility and water conservation functions remain largely unknown.Methods:This study investigated the soil nutrient contents of three different plantations(Larix principis-rupprechtii,Picea crassifolia,Pinus tabuliformis),soils and plant-soil feedbacks,as well as the interactions between soil physicochemical properties.Results:The results revealed that the leaves and litter layers strongly influenced soil nutrient availability through biogeochemical processes:P.tabuliformis had higher organic carbon,ratio of organic carbon to total nitrogen(C:N)and organic carbon to total phosphorus(C:P)in the leaves and litter layers than L.principis-rupprechtii or P.crassifolia,suggesting that higher C:N and C:P hindered litter decomposition.As a result,the L.principis-rupprechtii and P.crassifolia plantation forests significantly improved soil nutrients and clay components,compared with the P.tabuliformis plantation forest.Furthermore,the L.principis-rupprechtii and P.crassifolia plantation forests significantly improved the soil capacity,soil total porosity,and capillary porosity,decreased soil bulk density,and enhanced water storage capacity,compared with the P.tabuliformis plantation forest.The results of this study showed that,the strong link between plants and soil was tightly coupled to C:N and C:P,and there was a close correlation between soil particle size distribution and soil physicochemical properties.Conclusions:Therefore,our results recommend planting the L.principis-rupprechtii and P.crassifolia as the preferred tree species to enhance the soil fertility and water conservation functions,especially in semi-arid regions mountain forest ecosystems.展开更多
The purpose of the current study was to investigate the eco-physiological responses,in terms of growth and C:N:P stoichiometry of plants cultured from dimorphic seeds of a single-cell C4 annual Suaeda aralocaspica(Bun...The purpose of the current study was to investigate the eco-physiological responses,in terms of growth and C:N:P stoichiometry of plants cultured from dimorphic seeds of a single-cell C4 annual Suaeda aralocaspica(Bunge)Freitag and Schütze under elevated CO_(2).A climatic chamber experiment was conducted to examine the effects of ambient(720μg/L)and CO_(2)-enriched(1440μg/L)treatments on these responses in S.aralocaspica at vegetative and reproductive stages in 2012.Result showed that elevated CO_(2) significantly increased shoot dry weight,but decreased N:P ratio at both growth stages.Plants grown from dimorphic seeds did not exhibit significant differences in growth and C:N:P stoichiometric characteristics.The transition from vegetation to reproductive stage significantly increased shoot:root ratio,N and P contents,but decreased C:N,C:P and N:P ratios,and did not affect shoot dry weight.Moreover,our results indicate that the changes in N:P and C:N ratios between ambient and elevated CO_(2) are mainly caused by the decrease of N content under elevated CO_(2).These results provide an insight into nutritional metabolism of single-cell C4 plants under climate change.展开更多
Background The forest floor humus layer is an important carbon pool and serves as a key interface that influences forest soil carbon and nutrient cycling,especially in temperate and boreal forests.Over the past decade...Background The forest floor humus layer is an important carbon pool and serves as a key interface that influences forest soil carbon and nutrient cycling,especially in temperate and boreal forests.Over the past decades,China has implemented numerous forestry ecological programs,leading to an increasing quantity of forest floor litter and the formation of humus layers,which has altered the interface between aboveground litter and surface soil.Our previous study revealed that these alterations affect the litter decomposition rate;however,it is still unclear how the litter decomposition process changes,how nutrients are released or imported and the extent to which these changes depend on the humus layer.Results In this study,we used a 535-day in situ litterbag experiment to monitor the litter decomposition process and nutrient variations under forest floor humus layer removal in a Pinus sylvestris var.mongolica plantation in Northeast China.The results revealed that the litter decomposed quickly when a forest floor humus layer was present,with the decomposition rate constant(k value)increasing from 0.122 to 0.328.Accordingly,during decomposition,the litter C,N and P concentrations increased,whereas their contents varied only slightly(with the exception of the litter P content,which decreased significantly)compared with those in the treatment where the humus layer was removed.However,both the litter C and N contents decreased,whereas the litter P content increased significantly compared with the initial litter content.Moreover,the litter C:N,C:P and N:P ratios decreased significantly during decomposition.In addition,the microbial community diversity of the litter showed no significant change,whereas the relative abundances of several major fungal and bacterial taxa at the phylum and genus levels varied significantly.Furthermore,redundancy analysis revealed effective relationships among the k values,chemical traits and microbial communities,and the least squares method suggested that the C,P and C:P ratios of the litter were significantly correlated with the litter decomposition rate.Conclusions These results enhance our understanding of the role of the humus layer in forest soil-plant carbon and nutrient cycling and should be considered in carbon cycle models in the future.展开更多
The microbial biomass C,N and P of soils all over China were determined in this study to study their affecting factors.The results,about 100-417 mg C kg^-1 soil,18-51 mg Nkg^-1 soil and 4.4-27.3mg P kg^-1 soil,showed ...The microbial biomass C,N and P of soils all over China were determined in this study to study their affecting factors.The results,about 100-417 mg C kg^-1 soil,18-51 mg Nkg^-1 soil and 4.4-27.3mg P kg^-1 soil,showed the biomass C,N and P in linear relationship with the soil total organic C,toal N and soil organic P.The ratios of C:Nand C:P,ranging from 5.6 to 9.6 and from 11.2 to 48.4 respectively,were affected by soil pH.texture,crop rotation,macroclimate etc.The ratio of C:N in soil biomass increases gradually from the north to the south in China.展开更多
基金supported by the National Natural Science Foundation of China(Nos.31800369,32271686,U1904204)the State Scholarship Fund of Chinathe Innovation Scientists and Technicians Troop Construction Projects of Henan Province(No.182101510005)。
文摘Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant uptake.However,the effect of N deposition on the flexibility of carbon(C),N,and phosphorus(P)in forest plant-soil-microbe systems remains unclear.Methods:We conducted a meta-analysis based on 751 pairs of observations to evaluate the responses of plant,soil and microbial biomass C,N and P nutrients and stoichiometry to N addition in different N intensity(050,50–100,>100 kg·ha^(-1)·year^(-1)of N),duration(0–5,>5 year),method(understory,canopy),and matter(ammonium N,nitrate N,organic N,mixed N).Results:N addition significantly increased plant N:P(leaf:14.98%,root:13.29%),plant C:P(leaf:6.8%,root:25.44%),soil N:P(13.94%),soil C:P(10.86%),microbial biomass N:P(23.58%),microbial biomass C:P(12.62%),but reduced plant C:N(leaf:6.49%,root:9.02%).Furthermore,plant C:N:P stoichiometry changed significantly under short-term N inputs,while soil and microorganisms changed drastically under high N addition.Canopy N addition primarily affected plant C:N:P stoichiometry through altering plant N content,while understory N inputs altered more by influencing soil C and P content.Organic N significantly influenced plant and soil C:N and C:P,while ammonia N changed plant N:P.Plant C:P and soil C:N were strongly correlated with mean annual precipitation(MAT),and the C:N:P stoichiometric flexibility in soil and plant under N addition connected with soil depth.Besides,N addition decoupled the correlations between soil microorganisms and the plant.Conclusions:N addition significantly increased the C:P and N:P in soil,plant,and microbial biomass,reducing plant C:N,and aggravated forest P limitations.Significantly,these impacts were contingent on climate types,soil layers,and N input forms.The findings enhance our comprehension of the plant-soil system nutrient cycling mechanisms in forest ecosystems and plant strategy responses to N deposition.
基金funded by the National Ministry of Science and Technology Ecological Station(LZF2020-2025)the Longterm Ecological Observation Study of Alpine Pine in Southeast Tibet(Science and Technology Innovation Base)(XZ202301JD0001G)+1 种基金the Graduate Student Innovation Project of Tibet Agriculture and Animal Husbandry College(YJS2023-01)the Tibet Agriculture and Animal Husbandry College Talent Team Development Fund Project(XZNMXYRCXM-2024-10).
文摘Research on the multicomponent synergistic relationships between plants,litter,and soil from the perspective of ecological stoichiometry helps to understand nutrient cycling and distribution mechanisms within ecosystems.This study focused on Juniperus saltuaria,the dominant tree species in the forestline ecotone of Sygera Mountains,southeastern Xizang,China.We systematically measured and analyzed the Carbon(C),nitrogen(N),and phosphorus(P)contents and their relationships in plants(leaves,branches,trunks,fine roots),litter(undecomposed layer,partially decomposed layer,fully decomposed layer),and soil(0-10 cm,10-20 cm,20-40 cm)at different slope positions.The results showed significant differences in the C,N,and P contents and stoichiometry of plants and soil at different slope positions,while no significant differences were observed among litter layers.At the same slope position,the C,N,and P contents in leaves and surface soil were the highest,with soil nutrients significantly decreasing with increasing depth.For litter,the C content in the undecomposed layer was significantly higher than that in the partially and fully decomposed layers while the P content showed the opposite trend.Surface soil(0-20 cm)exhibited a decoupled relationship with plants but a coupled relationship with litter while deep soil(20-40 cm)showed a coupled relationship with plants.J.saltuaria showed faster growth rates on uphill slope.In this study area,J.saltuaria exhibited consistent trends of N,P,and N:P ratios homeostasis across different slope positions and organs,with leaves and fine roots both limited by N.Significant interactive effects between plants,litter,and soil nutrients were observed across different slope positions.Positive correlations were found between leaf and litter,and between fine root and leaf while the relationships between litter and soil,and between soil and fine root,varied.This study helps improve our understanding of the nutrient interactions between plants,litter,and soil in dominant species of alpine forest ecosystems,as well as their ecological adaptation mechanisms.
基金Under the auspices of Natural Science Foundation of China(No.U2106209,42071126)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA23050202)International Science Partnership Program of the Chinese Academy of Sciences(No.121311KYSB20190029)。
文摘Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this study,we examined the re-sponses of soil C,N,and P contents and their stoichiometric ratios to vegetation restoration age,focusing on below-ground processes and their relationships to aboveground vegetation community characteristics.We conducted an analysis of temporal gradients based on the'space for time'method to synthesize the effects of restoration age on soil C:N:P stoichiometry in the Yellow River Delta wetland of China.The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C:N:P stoichiometry.Specifically,restoration age significantly increased all topsoil C:N:P stoichiometries,except for soil total phosphorus(TP)and the C:N ratio,and slightly affected subsoil C:N:P stoichiometry.The effects of restoration age on the soil C:N ratio was well constrained owing to the coupled relationship between soil organic carbon(SOC)and total nitrogen(TN)contents,while soil TP con-tent was closely related to changes in plant species diversity.Importantly,we found that the topsoil C:N:P stoichiometry was signific-antly affected by plant species diversity,whereas the subsoil C:N:P stoichiometry was more easily regulated by pH and electric con-ductivity(EC).Overall,this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation,which is useful for further assessing soil C:N:P stoichiometry in coastal restoration wetlands.
基金This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20100101)a Major Special Science and Technology Project of Gansu Province(18ZD2FA009)the National Natural Science Foundation of China(NSFC)(31522013).
文摘Background:Large-scale afforestation can significantly change the ground cover and soil physicochemical properties,especially the soil fertility maintenance and water conservation functions of artificial forests,which are very important in semi-arid mountain ecosystems.However,how different tree species affect soil nutrients and soil physicochemical properties after afforestation,and which is the best plantation species for improving soil fertility and water conservation functions remain largely unknown.Methods:This study investigated the soil nutrient contents of three different plantations(Larix principis-rupprechtii,Picea crassifolia,Pinus tabuliformis),soils and plant-soil feedbacks,as well as the interactions between soil physicochemical properties.Results:The results revealed that the leaves and litter layers strongly influenced soil nutrient availability through biogeochemical processes:P.tabuliformis had higher organic carbon,ratio of organic carbon to total nitrogen(C:N)and organic carbon to total phosphorus(C:P)in the leaves and litter layers than L.principis-rupprechtii or P.crassifolia,suggesting that higher C:N and C:P hindered litter decomposition.As a result,the L.principis-rupprechtii and P.crassifolia plantation forests significantly improved soil nutrients and clay components,compared with the P.tabuliformis plantation forest.Furthermore,the L.principis-rupprechtii and P.crassifolia plantation forests significantly improved the soil capacity,soil total porosity,and capillary porosity,decreased soil bulk density,and enhanced water storage capacity,compared with the P.tabuliformis plantation forest.The results of this study showed that,the strong link between plants and soil was tightly coupled to C:N and C:P,and there was a close correlation between soil particle size distribution and soil physicochemical properties.Conclusions:Therefore,our results recommend planting the L.principis-rupprechtii and P.crassifolia as the preferred tree species to enhance the soil fertility and water conservation functions,especially in semi-arid regions mountain forest ecosystems.
基金This research was supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA2003010302)the National Natural Science Foundation of China(32171514)the State Key Laboratory of Desert and Oasis Ecology,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences(E1510107).
文摘The purpose of the current study was to investigate the eco-physiological responses,in terms of growth and C:N:P stoichiometry of plants cultured from dimorphic seeds of a single-cell C4 annual Suaeda aralocaspica(Bunge)Freitag and Schütze under elevated CO_(2).A climatic chamber experiment was conducted to examine the effects of ambient(720μg/L)and CO_(2)-enriched(1440μg/L)treatments on these responses in S.aralocaspica at vegetative and reproductive stages in 2012.Result showed that elevated CO_(2) significantly increased shoot dry weight,but decreased N:P ratio at both growth stages.Plants grown from dimorphic seeds did not exhibit significant differences in growth and C:N:P stoichiometric characteristics.The transition from vegetation to reproductive stage significantly increased shoot:root ratio,N and P contents,but decreased C:N,C:P and N:P ratios,and did not affect shoot dry weight.Moreover,our results indicate that the changes in N:P and C:N ratios between ambient and elevated CO_(2) are mainly caused by the decrease of N content under elevated CO_(2).These results provide an insight into nutritional metabolism of single-cell C4 plants under climate change.
基金supported by the National Key Research and Development Program of China(2024YFD150140302)the Natural Science Foundation of China(Nos.32271843,41888101 and 41871027)the project of forestry science and technology innovation platform(No.LLC20245)
文摘Background The forest floor humus layer is an important carbon pool and serves as a key interface that influences forest soil carbon and nutrient cycling,especially in temperate and boreal forests.Over the past decades,China has implemented numerous forestry ecological programs,leading to an increasing quantity of forest floor litter and the formation of humus layers,which has altered the interface between aboveground litter and surface soil.Our previous study revealed that these alterations affect the litter decomposition rate;however,it is still unclear how the litter decomposition process changes,how nutrients are released or imported and the extent to which these changes depend on the humus layer.Results In this study,we used a 535-day in situ litterbag experiment to monitor the litter decomposition process and nutrient variations under forest floor humus layer removal in a Pinus sylvestris var.mongolica plantation in Northeast China.The results revealed that the litter decomposed quickly when a forest floor humus layer was present,with the decomposition rate constant(k value)increasing from 0.122 to 0.328.Accordingly,during decomposition,the litter C,N and P concentrations increased,whereas their contents varied only slightly(with the exception of the litter P content,which decreased significantly)compared with those in the treatment where the humus layer was removed.However,both the litter C and N contents decreased,whereas the litter P content increased significantly compared with the initial litter content.Moreover,the litter C:N,C:P and N:P ratios decreased significantly during decomposition.In addition,the microbial community diversity of the litter showed no significant change,whereas the relative abundances of several major fungal and bacterial taxa at the phylum and genus levels varied significantly.Furthermore,redundancy analysis revealed effective relationships among the k values,chemical traits and microbial communities,and the least squares method suggested that the C,P and C:P ratios of the litter were significantly correlated with the litter decomposition rate.Conclusions These results enhance our understanding of the role of the humus layer in forest soil-plant carbon and nutrient cycling and should be considered in carbon cycle models in the future.
文摘The microbial biomass C,N and P of soils all over China were determined in this study to study their affecting factors.The results,about 100-417 mg C kg^-1 soil,18-51 mg Nkg^-1 soil and 4.4-27.3mg P kg^-1 soil,showed the biomass C,N and P in linear relationship with the soil total organic C,toal N and soil organic P.The ratios of C:Nand C:P,ranging from 5.6 to 9.6 and from 11.2 to 48.4 respectively,were affected by soil pH.texture,crop rotation,macroclimate etc.The ratio of C:N in soil biomass increases gradually from the north to the south in China.
