As a linkage between plants and soil,litter decomposition and its effect on nutrient recirculation have an important ecolog‐ical significance as they contribute to soil structure improvement and the restoration of de...As a linkage between plants and soil,litter decomposition and its effect on nutrient recirculation have an important ecolog‐ical significance as they contribute to soil structure improvement and the restoration of degraded ecosystems.Fragile eco‐systems in arid regions(both hot and cold)are depleted in soil organic matter,and as a result of various factors their circu‐lation of material and energy is slower.Here we discuss how litter decomposition is necessary to maintain the stability of fragile ecosystems.We reviewed research on litter decomposition carried out in arid regions.Our objective in this review is to outline how litter decomposition,and the subsequent buildup of organic matter in soil,is a key process determining the stability of fragile ecosystems.Our review shows that existing studies have focused on the influence of single ecologi‐cal factors on litter decomposition and nutrient cycling,and highlights how the exploration of interactions among factors determining litter decomposition is still lacking.This interaction is a key aspect,since in the real world,decomposition and nutrient return to soil of litter products is affected by multiple factors.We propose a network setup on a cross-regional scale using standardized methods(e.g.,the tea bag method)to understand litter decomposition and nutrient return in frag‐ile ecosystems.Such a unique network could contribute to establish predictive models suitable for litter decomposition and nutrient return in these areas,and thus could provide theoretical and practical support for regional ecological protec‐tion and high-quality development.展开更多
Changting County is located in western Fujian province. Natural, social and economic aspects of ecolog- ical restoration were studied in this area from 2000 to 2011, and the results are widely representative of subtro...Changting County is located in western Fujian province. Natural, social and economic aspects of ecolog- ical restoration were studied in this area from 2000 to 2011, and the results are widely representative of subtropical mountain ecosystem fragility across China. Great attention should be paid to the application of system theory and the harmony of human-nature relationships. This paper aims to provide the scientific theory to support strategies known as ＇harmony of man with nature＇, which means exerting natural regenesis potential by following natural law, transferring runoff from harm to benefit by operating on the ground and making material and economic virtuous cir- cles in land utilization by arousing human initiatives. It is necessary to transform ideas, tactics and technology and break technological bottlenecks, space limitations and systemic obstacles.展开更多
Backgrounds:Grazing prohibition and reduced grazing intensity,as two important“vegetation close-to-nature recovery”methods,have been suggested as economical and effective technologies for enhancing forage production...Backgrounds:Grazing prohibition and reduced grazing intensity,as two important“vegetation close-to-nature recovery”methods,have been suggested as economical and effective technologies for enhancing forage production.However,numerous studies have found that the yield of forage could be increased by removing or reducing grazing in a short time in some steady stage of alpine Kobresia meadows,but not in others.To reveal the mechanism behind this phenomenon,we proposed a series of experiments.Methods:We monitored the plant and soil characteristics in the key steady stages of Kobresia meadows under reduced and prohibited grazing conditions in the same geographic and climatic environments in the northeastern Qinghai-Tibet Plateau for 6 years.We estimated the relationships between the plant community and soil nutrients and obtained the following results.Results:All measured variables were positively correlated with each other.The plant community structure had higher path coefficients to aboveground biomass,soil organic matter,total nitrogen,and nitrate nitrogen than to other factors.The plant community structure played an important role in response to grazing intensity.Different plant functional groups(PFGs)had different responses to grazing intensity,which led to plant community re-establishment or re-organization under different grazing intensities.Poaceae and Kobresia were more sensitive to grazing intensity than other PFGs,and the ratio of Kobresia biomass(including Kobresia humilis and Kobresia pygmaea)to the total biomass of Poaceae and Kobresia could be used as an indicator of regime shifts within plant communities.With Kobresia pygmaea as the dominant species,the prohibition of grazing was not an efficient approach to increase the yield in the steady stages because this treatment needed more time to recover aboveground biomass.If Poaceae is the dominant PFG,grazing should only be prohibited for 3 years in the steady stages because the aboveground biomass will decrease if grazing is prohibited for more than 3 years.Conclusions:Therefore,the different steady stages of alpine meadows require different recovery methods to increase recovery efficiency and speed.展开更多
基金supported by the Key Research and Development Plan of Ning Xia Province,China(Grant No.2020BBF02003)the National Natural Science Foundation of China(Grant No.41877540)+1 种基金the Visiting Scholar Research Program of China Scholarship Council(Grant No.201804910131)the Second Tibetan Plateau Scientific Expedition and Research program(2019QZKK0305).
文摘As a linkage between plants and soil,litter decomposition and its effect on nutrient recirculation have an important ecolog‐ical significance as they contribute to soil structure improvement and the restoration of degraded ecosystems.Fragile eco‐systems in arid regions(both hot and cold)are depleted in soil organic matter,and as a result of various factors their circu‐lation of material and energy is slower.Here we discuss how litter decomposition is necessary to maintain the stability of fragile ecosystems.We reviewed research on litter decomposition carried out in arid regions.Our objective in this review is to outline how litter decomposition,and the subsequent buildup of organic matter in soil,is a key process determining the stability of fragile ecosystems.Our review shows that existing studies have focused on the influence of single ecologi‐cal factors on litter decomposition and nutrient cycling,and highlights how the exploration of interactions among factors determining litter decomposition is still lacking.This interaction is a key aspect,since in the real world,decomposition and nutrient return to soil of litter products is affected by multiple factors.We propose a network setup on a cross-regional scale using standardized methods(e.g.,the tea bag method)to understand litter decomposition and nutrient return in frag‐ile ecosystems.Such a unique network could contribute to establish predictive models suitable for litter decomposition and nutrient return in these areas,and thus could provide theoretical and practical support for regional ecological protec‐tion and high-quality development.
基金Fujian Major Science and Technology Foundation Programme(2001Z155)
文摘Changting County is located in western Fujian province. Natural, social and economic aspects of ecolog- ical restoration were studied in this area from 2000 to 2011, and the results are widely representative of subtropical mountain ecosystem fragility across China. Great attention should be paid to the application of system theory and the harmony of human-nature relationships. This paper aims to provide the scientific theory to support strategies known as ＇harmony of man with nature＇, which means exerting natural regenesis potential by following natural law, transferring runoff from harm to benefit by operating on the ground and making material and economic virtuous cir- cles in land utilization by arousing human initiatives. It is necessary to transform ideas, tactics and technology and break technological bottlenecks, space limitations and systemic obstacles.
基金The Natural Science Foundation of Qinghai Province for providing funding for“Research on health assessment and sustainable development in alpine Kobresia meadows in Qinghai Province”,Grant/Award Number:2020-ZJ-720。
文摘Backgrounds:Grazing prohibition and reduced grazing intensity,as two important“vegetation close-to-nature recovery”methods,have been suggested as economical and effective technologies for enhancing forage production.However,numerous studies have found that the yield of forage could be increased by removing or reducing grazing in a short time in some steady stage of alpine Kobresia meadows,but not in others.To reveal the mechanism behind this phenomenon,we proposed a series of experiments.Methods:We monitored the plant and soil characteristics in the key steady stages of Kobresia meadows under reduced and prohibited grazing conditions in the same geographic and climatic environments in the northeastern Qinghai-Tibet Plateau for 6 years.We estimated the relationships between the plant community and soil nutrients and obtained the following results.Results:All measured variables were positively correlated with each other.The plant community structure had higher path coefficients to aboveground biomass,soil organic matter,total nitrogen,and nitrate nitrogen than to other factors.The plant community structure played an important role in response to grazing intensity.Different plant functional groups(PFGs)had different responses to grazing intensity,which led to plant community re-establishment or re-organization under different grazing intensities.Poaceae and Kobresia were more sensitive to grazing intensity than other PFGs,and the ratio of Kobresia biomass(including Kobresia humilis and Kobresia pygmaea)to the total biomass of Poaceae and Kobresia could be used as an indicator of regime shifts within plant communities.With Kobresia pygmaea as the dominant species,the prohibition of grazing was not an efficient approach to increase the yield in the steady stages because this treatment needed more time to recover aboveground biomass.If Poaceae is the dominant PFG,grazing should only be prohibited for 3 years in the steady stages because the aboveground biomass will decrease if grazing is prohibited for more than 3 years.Conclusions:Therefore,the different steady stages of alpine meadows require different recovery methods to increase recovery efficiency and speed.
