Background:Agricultural yields have increased continuously over the last few decades.However,a focus solely on production can harm the environment.Diversification of agriculture has been suggested to increase producti...Background:Agricultural yields have increased continuously over the last few decades.However,a focus solely on production can harm the environment.Diversification of agriculture has been suggested to increase production and sustainability.Biodiversity experiments showed positive effects on ecosystems and productivity.However,application of these results to intensively managed grasslands has been questioned due to differences in plant species and management regimes.Research on whether diversity can benefit multifunctionality,that is,an integrated index of multiple ecosystem functions,under intensive management,is still scarce.Methods:To address this,we manipulated plant species richness from one to six species spanning three functional groups(legumes,herbs,and grasses)in intensively managed multispecies grassland leys and examined seven ecosystem functions.Results:We found that multifunctionality increased with functional group and species richness.Legume+herb mixtures showed high multifunctionality,while grass monocultures and mixtures with high proportions of grasses had low multifunctionality.Different plant species and plant communities drove different ecosystem functions.Legumes and herbs improved productivity and water availability,while grasses enhanced invasion resistance.These results indicate that multifunctionality and individual ecosystem functions can be promoted through targeted combinations of plants with complementary ecological traits.Conclusions:Plant diversity can improve multifunctionality also under intensive management,potentially benefitting agroeconomics and sustainability.展开更多
Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen（N） dynamics and nitrous oxide（N2O） emissions. However, it ...Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen（N） dynamics and nitrous oxide（N2O） emissions. However, it remains unclear how large-scale grassland reclamation will impact the grassland ecosystem as a whole. Here, we investigated the effects of the conversion from native to managed grasslands on soil N dynamics and N2O emissions by field experiments in Hulunber in northern China. Soil（0-10 cm）, nitrate（NO3-）,ammonium（NH4＋）, and microbial N were measured in plots in a temperate steppe（Leymus chinensis grassland） and two managed grasslands（Medicago sativa and Bromus inermis grasslands） in 2011 and 2012. The results showed conversion of L. chinensis grassland to M.sativa or B. inermis grasslands decreased concentrations of NO3--N, but did not change NH4-N . Soil microbial N was slightly decreased by the conversion of L. chinensis grassland to M.sativa, but increased by the conversion to B. inermis. The conversion of L. chinensis grassland to M. sativa（i.e., a legume grass） increased N2O emissions by 26.2%, while the conversion to the B. inermis（i.e., a non-legume grass） reduced N2O emissions by 33.1%. The conversion from native to managed grasslands caused large created variations in soil NO3-＋-N and NH4-N concentrations. Net N mineralization rates did not change significantly in growing season or vegetation type, but to net nitrification rate. These results provide evidence on how reclamation may impact the grassland ecosystem in terms of N dynamics and N2O emissions.展开更多
To mitigate the impacts of grassland degradation on the Qinghai–Tibetan Plateau(QTP), in recent decades China has been implementing large-scale conservation programs and has invested about 42 billion CNY(7 billion US...To mitigate the impacts of grassland degradation on the Qinghai–Tibetan Plateau(QTP), in recent decades China has been implementing large-scale conservation programs and has invested about 42 billion CNY(7 billion USD). However, these programs are faced with major challenges involving trade-offs between ecological function, livestock production and income of pastoralists.Scientific assessments, as well as technical and policy issues, have not fully captured the complex ecological,social and economic dynamics of the challenges facing grassland management on the QTP. Pastoral livestock production on the QTP is characterized by imbalance in both quality and quantity between livestock seasonal nutrient requirements and herbage production, which forces pastoralists to keep larger numbers of livestock for longer periods, leading to overgrazing. To solve these problems, an integrated crop-livestock system is promoted to improve the efficiency of livestock production and conserve natural grassland as well for a sustainable system for the QTP.展开更多
The semi-arid grasslands in Inner Mongolia, China have been degraded by long-term grazing. A series of ecological restoration strategies have been implemented to improve grassland service. However, little is known abo...The semi-arid grasslands in Inner Mongolia, China have been degraded by long-term grazing. A series of ecological restoration strategies have been implemented to improve grassland service. However, little is known about the effect of these ecological restoration practices on soil carbon and nitrogen storage. In this study, characteristics of vegetation and soil properties under continued grazing and exclusion of livestock for six years due to a nationwide conservation program—′Returning Grazing Lands to Grasslands(RGLG)′ were examined in semi-arid Hulun Buir grassland in Inner Mongolia, China. The results show that removal of grazing for six years resulted in a significant recovery in vegetation with higher above and below-ground biomass, but a lower soil bulk density and pH value. After six years of grazing exclusion, soil organic C and total N storage increased by 13.9% and 17.1%, respectively, which could be partly explained by decreased loss and increased input of C and N to soil. The effects of grazing exclusion on soil C and N concentration and storage primarily occurred in the upper soil depths. The results indicate that removal of grazing pressure within the RGLG program was an effective restoration approach to control grassland degradation in this region. However, more comprehensive studies are needed to evaluate the effectiveness of the RGLG program and to improve the management strategies for grassland restoration in this area.展开更多
牧场尺度放牧管理决策支持系统(decision support systems,DSS)是牧场管理、科学研究的重要工具.近些年来国际上开发了大量牧场放牧管理软件,不仅可以模拟牧草生长、动物生长,还可以模拟管理措施等,模拟运行结果可以为生产提供指导措施...牧场尺度放牧管理决策支持系统(decision support systems,DSS)是牧场管理、科学研究的重要工具.近些年来国际上开发了大量牧场放牧管理软件,不仅可以模拟牧草生长、动物生长,还可以模拟管理措施等,模拟运行结果可以为生产提供指导措施,同时为科学研究、教学和推广提供了优秀的工具.本文就国外放牧管理DSS的软件及小型计算器的开发与应用作了介绍,并简要介绍了目前国内研究现状,为国内放牧管理DSS的研究与应用提供参考.展开更多
基金Science Foundation Ireland Frontiers for the Future program,Grant/Award Number:19/FFP/6888Deutsche Forschungsgemeinschaft,Grant/Award Numbers:GSC 81,ME5474/1-1,WE3081/39-1。
文摘Background:Agricultural yields have increased continuously over the last few decades.However,a focus solely on production can harm the environment.Diversification of agriculture has been suggested to increase production and sustainability.Biodiversity experiments showed positive effects on ecosystems and productivity.However,application of these results to intensively managed grasslands has been questioned due to differences in plant species and management regimes.Research on whether diversity can benefit multifunctionality,that is,an integrated index of multiple ecosystem functions,under intensive management,is still scarce.Methods:To address this,we manipulated plant species richness from one to six species spanning three functional groups(legumes,herbs,and grasses)in intensively managed multispecies grassland leys and examined seven ecosystem functions.Results:We found that multifunctionality increased with functional group and species richness.Legume+herb mixtures showed high multifunctionality,while grass monocultures and mixtures with high proportions of grasses had low multifunctionality.Different plant species and plant communities drove different ecosystem functions.Legumes and herbs improved productivity and water availability,while grasses enhanced invasion resistance.These results indicate that multifunctionality and individual ecosystem functions can be promoted through targeted combinations of plants with complementary ecological traits.Conclusions:Plant diversity can improve multifunctionality also under intensive management,potentially benefitting agroeconomics and sustainability.
基金supported by The National Basic Research Program (973) of China (No. 2015CB150800)the National Key Research and Development Program of China (No. 2016YFC0500603)+1 种基金the China Agriculture Research System “China agriculture research system” (No. CARS-35)the National Nonprofit Institute Research Grant of CAAS (No. 647-53)
文摘Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen（N） dynamics and nitrous oxide（N2O） emissions. However, it remains unclear how large-scale grassland reclamation will impact the grassland ecosystem as a whole. Here, we investigated the effects of the conversion from native to managed grasslands on soil N dynamics and N2O emissions by field experiments in Hulunber in northern China. Soil（0-10 cm）, nitrate（NO3-）,ammonium（NH4＋）, and microbial N were measured in plots in a temperate steppe（Leymus chinensis grassland） and two managed grasslands（Medicago sativa and Bromus inermis grasslands） in 2011 and 2012. The results showed conversion of L. chinensis grassland to M.sativa or B. inermis grasslands decreased concentrations of NO3--N, but did not change NH4-N . Soil microbial N was slightly decreased by the conversion of L. chinensis grassland to M.sativa, but increased by the conversion to B. inermis. The conversion of L. chinensis grassland to M. sativa（i.e., a legume grass） increased N2O emissions by 26.2%, while the conversion to the B. inermis（i.e., a non-legume grass） reduced N2O emissions by 33.1%. The conversion from native to managed grasslands caused large created variations in soil NO3-＋-N and NH4-N concentrations. Net N mineralization rates did not change significantly in growing season or vegetation type, but to net nitrification rate. These results provide evidence on how reclamation may impact the grassland ecosystem in terms of N dynamics and N2O emissions.
基金funded by the National Key Research and Development Program (2016YFC0501905)the Science and Technology Service Network Initiative of Chinese Academy of Sciences (KFJ-STS-ZDTP-013)
文摘To mitigate the impacts of grassland degradation on the Qinghai–Tibetan Plateau(QTP), in recent decades China has been implementing large-scale conservation programs and has invested about 42 billion CNY(7 billion USD). However, these programs are faced with major challenges involving trade-offs between ecological function, livestock production and income of pastoralists.Scientific assessments, as well as technical and policy issues, have not fully captured the complex ecological,social and economic dynamics of the challenges facing grassland management on the QTP. Pastoral livestock production on the QTP is characterized by imbalance in both quality and quantity between livestock seasonal nutrient requirements and herbage production, which forces pastoralists to keep larger numbers of livestock for longer periods, leading to overgrazing. To solve these problems, an integrated crop-livestock system is promoted to improve the efficiency of livestock production and conserve natural grassland as well for a sustainable system for the QTP.
基金Under the auspices of Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA05060103)National Natural Science Foundation of China(No.41105117)State Key Laboratory of Forest and Soil Ecology(No.LFSE2013-06)
文摘The semi-arid grasslands in Inner Mongolia, China have been degraded by long-term grazing. A series of ecological restoration strategies have been implemented to improve grassland service. However, little is known about the effect of these ecological restoration practices on soil carbon and nitrogen storage. In this study, characteristics of vegetation and soil properties under continued grazing and exclusion of livestock for six years due to a nationwide conservation program—′Returning Grazing Lands to Grasslands(RGLG)′ were examined in semi-arid Hulun Buir grassland in Inner Mongolia, China. The results show that removal of grazing for six years resulted in a significant recovery in vegetation with higher above and below-ground biomass, but a lower soil bulk density and pH value. After six years of grazing exclusion, soil organic C and total N storage increased by 13.9% and 17.1%, respectively, which could be partly explained by decreased loss and increased input of C and N to soil. The effects of grazing exclusion on soil C and N concentration and storage primarily occurred in the upper soil depths. The results indicate that removal of grazing pressure within the RGLG program was an effective restoration approach to control grassland degradation in this region. However, more comprehensive studies are needed to evaluate the effectiveness of the RGLG program and to improve the management strategies for grassland restoration in this area.
文摘牧场尺度放牧管理决策支持系统(decision support systems,DSS)是牧场管理、科学研究的重要工具.近些年来国际上开发了大量牧场放牧管理软件,不仅可以模拟牧草生长、动物生长,还可以模拟管理措施等,模拟运行结果可以为生产提供指导措施,同时为科学研究、教学和推广提供了优秀的工具.本文就国外放牧管理DSS的软件及小型计算器的开发与应用作了介绍,并简要介绍了目前国内研究现状,为国内放牧管理DSS的研究与应用提供参考.
