Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan Plateau.However,to date,the effects of long-term grazing exclusion measures on the process of restoring d...Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan Plateau.However,to date,the effects of long-term grazing exclusion measures on the process of restoring degraded alpine meadows have not been evaluated.In this study,moderately degraded plots,in which the vegetation coverage was approximately 65%and the dominant plant species was Potentilla anserina L,with grazing exclusion for 2 to 23 years,were selected in alpine meadows of Haibei in Qinghai-Tibet Plateau.Plant coverage,plant height,biomass,soil bulk density,saturated water content,soil organic carbon(SOC)and total nitrogen(TN)were evaluated.The results were as follows:(1)With aboveground biomass and total saturated water content at 0-40 cm depth,the average SOC and TN contents in moderately degraded alpine meadows increased as a power function,and the plant height increased as a log function.(2)The average soil bulk density at 0-40 cm depth first decreased and then increased with increasing grazing exclusion duration,and the minimum value of 0.90 g·cm^(-3) was reached at 15.23 years.The plant coverage,total belowground biomass at 0-40 cm depth,total aboveground and belowground biomass first increased and then decreased,their maximum values(80.49%,2452.92g·m^(-2),2891.06 g·m^(-2))were reached at 9.41,9.46 and 10.25 years,respectively.Long-term grazing exclusion is apparently harmful for the sustainable restoration of degraded alpine meadows.The optimal duration of grazing exclusion for the restoration of moderately degraded alpine meadows was 10 years.This research suggests that moderate disturbance should be allowed in moderately degraded alpine meadows after 10years of grazing exclusion.展开更多
基于Web of Science、CNKI及Derwent Innovations Index数据源,利用Thomson Data Analyzer和Excel软件对1998~2017年草地退化及恢复治理文献进行计量分析,以深入了解全球和国内草地退化及恢复治理研究进展和发展趋势。结果表明:近20年...基于Web of Science、CNKI及Derwent Innovations Index数据源,利用Thomson Data Analyzer和Excel软件对1998~2017年草地退化及恢复治理文献进行计量分析,以深入了解全球和国内草地退化及恢复治理研究进展和发展趋势。结果表明:近20年国际草地退化及恢复治理研究年发文量呈先稳定后增加的趋势,中国和美国是草地退化及恢复治理研究的核心力量,二者的总发文量、总引频次和高被引论文数等指标均居前2位。草地退化及恢复治理领域发文量较多的研究机构和大学主要在中国和美国,中国科学院发文量居榜首;英国的《Land Degradation&Development》和美国的《Restoration Ecology》是发表草地退化文章质量和数量较高的期刊。近20年来,中国草地退化及恢复治理研究年发文量呈先快速增加后逐渐降低的趋势,内蒙古和青藏高原是草地退化及恢复治理研究的重点区域。退化草地的治理主要集中在建设人工半人工草地、减轻牧压、施肥、围栏封育、灭毒杂草及补播等恢复措施方面,但有关退化草地恢复措施的专利极少,亟待加强。整体而言,有关草地退化及恢复治理的研究已趋于稳定,未来的研究应加强退化草地恢复相关措施技术的专利化应用,提高相关技术的实用化和规模化。展开更多
Remote sensing(RS) technologies provide robust techniques for quantifying net primary productivity(NPP) which is a key component of ecosystem production management. Applying RS, the confounding effects of carbon consu...Remote sensing(RS) technologies provide robust techniques for quantifying net primary productivity(NPP) which is a key component of ecosystem production management. Applying RS, the confounding effects of carbon consumed by livestock grazing were neglected by previous studies, which created uncertainties and underestimation of NPP for the grazed lands. The grasslands in Xinjiang were selected as a case study to improve the RS based NPP estimation. A defoliation formulation model(DFM) based on RS is developed to evaluate the extent of underestimated NPP between 1982 and 2011. The estimates were then used to examine the spatiotemporal patterns of the calculated NPP. Results show that average annual underestimated NPP was 55.74 gC·m^(-2)yr^(-1) over the time period understudied, accounting for 29.06% of the total NPP for the Xinjiang grasslands. The spatial distribution of underestimated NPP is related to both grazing intensity and time. Data for the Xinjiang grasslands show that the average annual NPP was 179.41 gC·m^(-2)yr^(-1), the annual NPP with an increasing trend was observed at a rate of 1.04 gC·m^(-2)yr^(-1) between 1982 and 2011. The spatial distribution of NPP reveals distinct variations from high to low encompassing the geolocations of the Tianshan Mountains, northern and southern Xinjiang Province and corresponding with mid-mountain meadow, typical grassland, desert grassland, alpine meadow, and saline meadow grassland types. This study contributes to improving RS-based NPP estimations for grazed land and provides a more accurate data to support the scientific management of fragile grassland ecosystems in Xinjiang.展开更多
基金funded by the National Natural Science Foundation of China(32001149,U20A2006,31971507)Applied Basic Research Project of Qinghai Province(2022-ZJ-716)+3 种基金Youth Innovation Promotion Association CAS(2022436)Joint Grant from Chinese Academy of Sciences-People’s Government of Qinghai Province on Sanjiangyuan National Park(LHZX-2020-07)Chinese Academy of Science(CAS)"Light of West China"Program(2018)"The effect of grazing on grassland productivity in the basin of Qinghai Lake"。
文摘Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan Plateau.However,to date,the effects of long-term grazing exclusion measures on the process of restoring degraded alpine meadows have not been evaluated.In this study,moderately degraded plots,in which the vegetation coverage was approximately 65%and the dominant plant species was Potentilla anserina L,with grazing exclusion for 2 to 23 years,were selected in alpine meadows of Haibei in Qinghai-Tibet Plateau.Plant coverage,plant height,biomass,soil bulk density,saturated water content,soil organic carbon(SOC)and total nitrogen(TN)were evaluated.The results were as follows:(1)With aboveground biomass and total saturated water content at 0-40 cm depth,the average SOC and TN contents in moderately degraded alpine meadows increased as a power function,and the plant height increased as a log function.(2)The average soil bulk density at 0-40 cm depth first decreased and then increased with increasing grazing exclusion duration,and the minimum value of 0.90 g·cm^(-3) was reached at 15.23 years.The plant coverage,total belowground biomass at 0-40 cm depth,total aboveground and belowground biomass first increased and then decreased,their maximum values(80.49%,2452.92g·m^(-2),2891.06 g·m^(-2))were reached at 9.41,9.46 and 10.25 years,respectively.Long-term grazing exclusion is apparently harmful for the sustainable restoration of degraded alpine meadows.The optimal duration of grazing exclusion for the restoration of moderately degraded alpine meadows was 10 years.This research suggests that moderate disturbance should be allowed in moderately degraded alpine meadows after 10years of grazing exclusion.
文摘基于Web of Science、CNKI及Derwent Innovations Index数据源,利用Thomson Data Analyzer和Excel软件对1998~2017年草地退化及恢复治理文献进行计量分析,以深入了解全球和国内草地退化及恢复治理研究进展和发展趋势。结果表明:近20年国际草地退化及恢复治理研究年发文量呈先稳定后增加的趋势,中国和美国是草地退化及恢复治理研究的核心力量,二者的总发文量、总引频次和高被引论文数等指标均居前2位。草地退化及恢复治理领域发文量较多的研究机构和大学主要在中国和美国,中国科学院发文量居榜首;英国的《Land Degradation&Development》和美国的《Restoration Ecology》是发表草地退化文章质量和数量较高的期刊。近20年来,中国草地退化及恢复治理研究年发文量呈先快速增加后逐渐降低的趋势,内蒙古和青藏高原是草地退化及恢复治理研究的重点区域。退化草地的治理主要集中在建设人工半人工草地、减轻牧压、施肥、围栏封育、灭毒杂草及补播等恢复措施方面,但有关退化草地恢复措施的专利极少,亟待加强。整体而言,有关草地退化及恢复治理的研究已趋于稳定,未来的研究应加强退化草地恢复相关措施技术的专利化应用,提高相关技术的实用化和规模化。
基金supported by the international Partnership Program of the Chinese Academy of Science(Grant No.131965KYSB20160004)the National Natural Science Foundation of China(Grant No.U1803243)+1 种基金the Network Plan of the Science and Technology Service,Chinese Academy of Sciences(STS Plan)Qinghai innovation platform construction project(2017-ZJ-Y20)
文摘Remote sensing(RS) technologies provide robust techniques for quantifying net primary productivity(NPP) which is a key component of ecosystem production management. Applying RS, the confounding effects of carbon consumed by livestock grazing were neglected by previous studies, which created uncertainties and underestimation of NPP for the grazed lands. The grasslands in Xinjiang were selected as a case study to improve the RS based NPP estimation. A defoliation formulation model(DFM) based on RS is developed to evaluate the extent of underestimated NPP between 1982 and 2011. The estimates were then used to examine the spatiotemporal patterns of the calculated NPP. Results show that average annual underestimated NPP was 55.74 gC·m^(-2)yr^(-1) over the time period understudied, accounting for 29.06% of the total NPP for the Xinjiang grasslands. The spatial distribution of underestimated NPP is related to both grazing intensity and time. Data for the Xinjiang grasslands show that the average annual NPP was 179.41 gC·m^(-2)yr^(-1), the annual NPP with an increasing trend was observed at a rate of 1.04 gC·m^(-2)yr^(-1) between 1982 and 2011. The spatial distribution of NPP reveals distinct variations from high to low encompassing the geolocations of the Tianshan Mountains, northern and southern Xinjiang Province and corresponding with mid-mountain meadow, typical grassland, desert grassland, alpine meadow, and saline meadow grassland types. This study contributes to improving RS-based NPP estimations for grazed land and provides a more accurate data to support the scientific management of fragile grassland ecosystems in Xinjiang.
