对陆上生态体系而言,植物生理季节性变化是衡量其对气候转变反响的关键度量尺度,尤其对全球气温上升现象极为敏感的高纬度与高海拔地带的植物生理季节性。本研究借助MOD13A1卫星遥感资料,叠加温度与降水数据,剖析2000~2021年间蒙古国西...对陆上生态体系而言,植物生理季节性变化是衡量其对气候转变反响的关键度量尺度,尤其对全球气温上升现象极为敏感的高纬度与高海拔地带的植物生理季节性。本研究借助MOD13A1卫星遥感资料,叠加温度与降水数据,剖析2000~2021年间蒙古国西部地区植被生长季始期(Start of growing season,SOS)、生长季长度(Length of growing season,LOS)以及生长季末期(End of growing season,EOS)的时空变化特征和海拔依赖性变化机制。结果如下:(1)蒙古国西部地区的SOS主要集中在第90~125 d,近22 a来SOS呈微弱的提前趋势,提前幅度为0.23 d/a。(2)植被物候与气象要素的关系表明,2月的气温和降水与SOS显著负相关(P<0.05),1月的气温和降水与SOS显著正相关(P<0.05),而EOS主要受8月气温和降水的影响。(3)草甸草原和典型草原SOS主要受降水影响,高山草原、荒漠草原以及针叶林的SOS主要受气温影响,所有植被类型的EOS对温度的响应更大。总的来说,研究区植被物候与气候因子表现出季节性的差异,响应规律复杂。展开更多
使用淮河流域1981年至2020年的149个气象站点的气温和相对湿度数据,分析了流域暖季极端高温干旱复合事件(Compound Drought and Heat Events,CDHEs)的时空演变特征,并通过趋势分析和相关分析法探讨了CDHEs与气候和植被的关系。结果表明:...使用淮河流域1981年至2020年的149个气象站点的气温和相对湿度数据,分析了流域暖季极端高温干旱复合事件(Compound Drought and Heat Events,CDHEs)的时空演变特征,并通过趋势分析和相关分析法探讨了CDHEs与气候和植被的关系。结果表明:(1)CDHEs的发生日数在年代际尺度上呈现明显的增加趋势,并且范围扩大,频发区逐渐向淮河流域中西部移动;(2)在年际尺度上,CDHEs随时间序列呈显著的波动上升趋势,空间分布上以西北部为中心向四周递减。连续CDHEs事件呈年际变化,最大2至4天的连续事件存在波动,2019年达到高峰,并且在流域内零散或成片出现;(3)在月际尺度上,CDHEs的发生日数在6月最多,其次是5月、7月、9月和8月。淮河流域入汛前的旱情和入汛后的旱涝急转都容易导致CDHEs发生,而且随着月际变化向南移动;(4)CDHEs对水热条件和大气环流具有特别的敏感性。在850hPa反气旋和500hPa显著高压异常的控制下,高温、低湿、高蒸发和降水少的气候背景有利于淮河地区CDHEs的形成,尤其是在淮河中西部地区。因此,CDHEs的发生与气候变化密切相关;(5)CDHEs与植被生长也存在显著关系。CDHEs与GPP呈显著的负相关,而与NDVI呈显著的正相关,显著地区的土地类型以耕地和城乡、工矿、居民用地为主。GPP和NDVI的不同步可能是因为多种因素的非线性相互作用,而不仅仅是单一因素的影响。此外,对于GPP和NDVI来说,土壤含水量至关重要。总之,本文对淮河流域CDHEs的时空分布特征进行了深入研究,并探讨了其与气候和植被的关系。研究结果可以为该地区的气象灾害防御和生态环境保护提供科学依据和参考。展开更多
[目的]揭示我国北方草地年总初级生产力未来时空变化规律,为草地恢复及保护的政策制定提供重要依据。[方法]基于CMIP6中9个地球系统模式总初级生产力(Gross Primary Productivity,GPP)模拟数据,采用多模式集合平均(MME)的方法,在SSP1-2....[目的]揭示我国北方草地年总初级生产力未来时空变化规律,为草地恢复及保护的政策制定提供重要依据。[方法]基于CMIP6中9个地球系统模式总初级生产力(Gross Primary Productivity,GPP)模拟数据,采用多模式集合平均(MME)的方法,在SSP1-2.6,SSP2-4.5,SSP3-7.0和SSP5-8.5未来情景下预估了21世纪我国北方草地生态系统AGPP的时空变化。[结果](1)多模式集合(MME)模拟的准确性和年度趋势相关系数达到0.83,较其他单个模式更准确。(2)1982—2100年,4个情景均得出我国北方草地AGPP整体呈现上升趋势,温室气体高排放情景下的上升趋势大于温室气体低排放情景下的上升趋势。(3)空间上,我国北方草地平均AGPP在历史及未来情景下均呈西北到东南递增的趋势,SSP1-2.6情景下AGPP年均值最低〔308.03 g C/(m^(2)·a)〕,SSP5-8.5情景下最高〔389.63 g C/(m^(2)·a)〕。(4)在4个未来情景下的不同草地类型中,温性草原AGPP年均值最高〔SSP1-2.6情景下为445.44 g C/(m^(2)·a),SSP2-4.5情景下为474.53 g C/(m^(2)·a),SSP3-7.0情景下为532.42 g C/(m^(2)·a),SSP5-8.5情景下为558.14 g C/(m^(2)·a)〕,稀疏灌丛最低〔SSP1-2.6情景下为128.51 g C/(m^(2)·a),SSP2-4.5情景下为141.31 g C/(m^(2)·a),SSP3-7.0情景下为155.38 g C/(m^(2)·a),SSP5-8.5情景下为167.29 g C/(m^(2)·a)〕。[结论]我国北方草地AGPP未来呈显著增长趋势,不同情景下AGPP的增长趋势各不相同,排放情景越高增长越显著,未来应加强对我国北方草地AGPP变化的研究。展开更多
Climate change poses a serious long-term threat to biodiversity.To effectively reduce biodiversity loss,conservationists need to have a thorough understanding of the preferred habitats of species and the variables tha...Climate change poses a serious long-term threat to biodiversity.To effectively reduce biodiversity loss,conservationists need to have a thorough understanding of the preferred habitats of species and the variables that affect their distribution.Therefore,predicting the impact of climate change on speciesappropriate habitats may help mitigate the potential threats to biodiversity distribution.Xerophyta,a monocotyledonous genus of the family Velloziaceae is native to mainland Africa,Madagascar,and the Arabian Peninsula.The key drivers of Xerophyta habitat distribution and preference are unknown.Using 308 species occurrence data and eight environmental variables,the MaxEnt model was used to determine the potential distribution of six Xerophyta species in Africa under past,current and future climate change scenarios.The results showed that the models had a good predictive ability(Area Under the Curve and True Skill Statistics values for all SDMs were more than 0.902),indicating high accuracy in forecasting the potential geographic distribution of Xerophyta species.The main bioclimatic variables that impacted potential distributions of most Xerophyta species were mean temperature of the driest quarter(Bio9)and precipitation of the warmest quarter(Bio18).According to our models,tropical Africa has zones of moderate and high suitability for Xerophyta taxa,which is consistent with the majority of documented species localities.The habitat suitability of the existing range of the Xerophyta species varied based on the climate scenario,with most species experiencing a range loss greater than the range gain regardless of the climate scenario.The projected spatiotemporal patterns of Xerophyta species help guide recommendations for conservation efforts.展开更多
Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional pr...Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate warming.In this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations.To achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV classification.We find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and precipitation.Notably,we observe an unexpected transition between tundra and savanna despite their geographical distance.The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each group.Indeed,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate.The spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.展开更多
文摘对陆上生态体系而言,植物生理季节性变化是衡量其对气候转变反响的关键度量尺度,尤其对全球气温上升现象极为敏感的高纬度与高海拔地带的植物生理季节性。本研究借助MOD13A1卫星遥感资料,叠加温度与降水数据,剖析2000~2021年间蒙古国西部地区植被生长季始期(Start of growing season,SOS)、生长季长度(Length of growing season,LOS)以及生长季末期(End of growing season,EOS)的时空变化特征和海拔依赖性变化机制。结果如下:(1)蒙古国西部地区的SOS主要集中在第90~125 d,近22 a来SOS呈微弱的提前趋势,提前幅度为0.23 d/a。(2)植被物候与气象要素的关系表明,2月的气温和降水与SOS显著负相关(P<0.05),1月的气温和降水与SOS显著正相关(P<0.05),而EOS主要受8月气温和降水的影响。(3)草甸草原和典型草原SOS主要受降水影响,高山草原、荒漠草原以及针叶林的SOS主要受气温影响,所有植被类型的EOS对温度的响应更大。总的来说,研究区植被物候与气候因子表现出季节性的差异,响应规律复杂。
文摘使用淮河流域1981年至2020年的149个气象站点的气温和相对湿度数据,分析了流域暖季极端高温干旱复合事件(Compound Drought and Heat Events,CDHEs)的时空演变特征,并通过趋势分析和相关分析法探讨了CDHEs与气候和植被的关系。结果表明:(1)CDHEs的发生日数在年代际尺度上呈现明显的增加趋势,并且范围扩大,频发区逐渐向淮河流域中西部移动;(2)在年际尺度上,CDHEs随时间序列呈显著的波动上升趋势,空间分布上以西北部为中心向四周递减。连续CDHEs事件呈年际变化,最大2至4天的连续事件存在波动,2019年达到高峰,并且在流域内零散或成片出现;(3)在月际尺度上,CDHEs的发生日数在6月最多,其次是5月、7月、9月和8月。淮河流域入汛前的旱情和入汛后的旱涝急转都容易导致CDHEs发生,而且随着月际变化向南移动;(4)CDHEs对水热条件和大气环流具有特别的敏感性。在850hPa反气旋和500hPa显著高压异常的控制下,高温、低湿、高蒸发和降水少的气候背景有利于淮河地区CDHEs的形成,尤其是在淮河中西部地区。因此,CDHEs的发生与气候变化密切相关;(5)CDHEs与植被生长也存在显著关系。CDHEs与GPP呈显著的负相关,而与NDVI呈显著的正相关,显著地区的土地类型以耕地和城乡、工矿、居民用地为主。GPP和NDVI的不同步可能是因为多种因素的非线性相互作用,而不仅仅是单一因素的影响。此外,对于GPP和NDVI来说,土壤含水量至关重要。总之,本文对淮河流域CDHEs的时空分布特征进行了深入研究,并探讨了其与气候和植被的关系。研究结果可以为该地区的气象灾害防御和生态环境保护提供科学依据和参考。
文摘[目的]揭示我国北方草地年总初级生产力未来时空变化规律,为草地恢复及保护的政策制定提供重要依据。[方法]基于CMIP6中9个地球系统模式总初级生产力(Gross Primary Productivity,GPP)模拟数据,采用多模式集合平均(MME)的方法,在SSP1-2.6,SSP2-4.5,SSP3-7.0和SSP5-8.5未来情景下预估了21世纪我国北方草地生态系统AGPP的时空变化。[结果](1)多模式集合(MME)模拟的准确性和年度趋势相关系数达到0.83,较其他单个模式更准确。(2)1982—2100年,4个情景均得出我国北方草地AGPP整体呈现上升趋势,温室气体高排放情景下的上升趋势大于温室气体低排放情景下的上升趋势。(3)空间上,我国北方草地平均AGPP在历史及未来情景下均呈西北到东南递增的趋势,SSP1-2.6情景下AGPP年均值最低〔308.03 g C/(m^(2)·a)〕,SSP5-8.5情景下最高〔389.63 g C/(m^(2)·a)〕。(4)在4个未来情景下的不同草地类型中,温性草原AGPP年均值最高〔SSP1-2.6情景下为445.44 g C/(m^(2)·a),SSP2-4.5情景下为474.53 g C/(m^(2)·a),SSP3-7.0情景下为532.42 g C/(m^(2)·a),SSP5-8.5情景下为558.14 g C/(m^(2)·a)〕,稀疏灌丛最低〔SSP1-2.6情景下为128.51 g C/(m^(2)·a),SSP2-4.5情景下为141.31 g C/(m^(2)·a),SSP3-7.0情景下为155.38 g C/(m^(2)·a),SSP5-8.5情景下为167.29 g C/(m^(2)·a)〕。[结论]我国北方草地AGPP未来呈显著增长趋势,不同情景下AGPP的增长趋势各不相同,排放情景越高增长越显著,未来应加强对我国北方草地AGPP变化的研究。
基金supported by grants from the International Partnership Program of Chinese Academy of Sciences (151853KYSB20190027)Sino-Africa Joint Research Center, CAS (SAJC202101)The ANSO Scholarship for Young Talents, PhD Fellowship Program University of Chinese Academy of Sciences, China
文摘Climate change poses a serious long-term threat to biodiversity.To effectively reduce biodiversity loss,conservationists need to have a thorough understanding of the preferred habitats of species and the variables that affect their distribution.Therefore,predicting the impact of climate change on speciesappropriate habitats may help mitigate the potential threats to biodiversity distribution.Xerophyta,a monocotyledonous genus of the family Velloziaceae is native to mainland Africa,Madagascar,and the Arabian Peninsula.The key drivers of Xerophyta habitat distribution and preference are unknown.Using 308 species occurrence data and eight environmental variables,the MaxEnt model was used to determine the potential distribution of six Xerophyta species in Africa under past,current and future climate change scenarios.The results showed that the models had a good predictive ability(Area Under the Curve and True Skill Statistics values for all SDMs were more than 0.902),indicating high accuracy in forecasting the potential geographic distribution of Xerophyta species.The main bioclimatic variables that impacted potential distributions of most Xerophyta species were mean temperature of the driest quarter(Bio9)and precipitation of the warmest quarter(Bio18).According to our models,tropical Africa has zones of moderate and high suitability for Xerophyta taxa,which is consistent with the majority of documented species localities.The habitat suitability of the existing range of the Xerophyta species varied based on the climate scenario,with most species experiencing a range loss greater than the range gain regardless of the climate scenario.The projected spatiotemporal patterns of Xerophyta species help guide recommendations for conservation efforts.
基金funded by the National Natural Science Foundation of China(grants No.30960264,31160475 and 42071258)Open Research Fund of TPESER(grant No.TPESER202208)+2 种基金Special Fund for Basic Scientific Research of Central Colleges,Chang’an University,China(grant No.300102353501)Natural Science Foundation of Gansu Province,China(grant No.22JR5RA857)Higher Education Novel Foundation of Gansu Province,China(grant No.2021B-130)。
文摘Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate warming.In this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations.To achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV classification.We find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and precipitation.Notably,we observe an unexpected transition between tundra and savanna despite their geographical distance.The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each group.Indeed,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate.The spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.
