为了应对近海渔业资源日益衰退的问题,为实施基于空间的渔业管理提供必要信息,以江苏南部海域小黄鱼为研究对象,根据2019—2022年在该海域进行的季节性渔业资源综合调查,结合5个生物和非生物因子,采用组合物种分布模型(Ensemble species...为了应对近海渔业资源日益衰退的问题,为实施基于空间的渔业管理提供必要信息,以江苏南部海域小黄鱼为研究对象,根据2019—2022年在该海域进行的季节性渔业资源综合调查,结合5个生物和非生物因子,采用组合物种分布模型(Ensemble species distribution model,ESDM),研究了该海域小黄鱼的空间分布特征及其主要影响因素。结果显示,相较于单一物种分布模型,组合物种分布模型具有更高的AUC值(春季:0.995±0.002;秋季:0.985±0.001)和TSS值(春季:0.935±0.038;秋季:0.903±0.029)。在春季,底层水温和底层盐度的重要性水平最高(0.40和0.38),而在秋季叶绿素a和饵料生物丰度对小黄鱼空间分布的影响较大,其重要性分别为0.53和0.46。春季小黄鱼主要分布在近岸浅海区域,整体呈条带状分布;秋季小黄鱼则主要分布于水深较深的远岸水域,且适宜分布的海域范围要大于春季,整体呈块状分布。此外,小黄鱼的空间分布特征亦呈现出明显的年际差异,例如在2021年,其适宜栖息地面积明显小于其他年份,分布范围也仅限于局部区域。研究表明,组合物种分布模型具有更优的预测性能,能够更好地反映小黄鱼的栖息分布特征及其影响因素;不同季节小黄鱼的适生区及影响因素各有差异。本研究可为揭示该海域小黄鱼的时空分布特征及其变化规律提供理论依据,为实施基于空间的渔业管理和保护区选划提供基础资料。展开更多
物种的空间分布能够反映个体在空间上的相互关系,是物种与环境长期适应和选择的结果,对物种的生长发育和资源利用等都具有显著影响。本研究基于2013—2022年春季和秋季在海州湾及其邻近海域进行的底拖网调查数据,构建了10种单一物种分...物种的空间分布能够反映个体在空间上的相互关系,是物种与环境长期适应和选择的结果,对物种的生长发育和资源利用等都具有显著影响。本研究基于2013—2022年春季和秋季在海州湾及其邻近海域进行的底拖网调查数据,构建了10种单一物种分布模型(species distribution model,SDM),结合真实技巧统计值(true skill statistic,TSS)和受试者工作特征曲线下面积值(area under ROCcurve,AUC)筛选预测精度和准确性较优的模型作为基础模型,并通过加权的方法分别构建不同季节的组合物种分布模型(ensemble species distribution model,ESDM),以解析矛尾虾虎鱼(Chaeturichthys stigmatias)的空间分布特征及其影响因素。结果表明,ESDM能够有效降低单一模型预测的不确定性,提高模型预测的精度,更加准确地解析海州湾矛尾虾虎鱼的空间分布特征。2013—2022年春季,矛尾虾虎鱼集中分布于海州湾西部近岸和南部海域,东部和中北部海域分布较少,分布重心的经度和纬度偏移范围大约为1°;秋季主要分布于海州湾西南部海域,分布重心呈辐射状小幅度移动。本研究发现,与矛尾虾虎鱼空间分布存在显著相关的影响因子为水深、饵料丰度、底层水温和底层盐度,其中饵料丰度是春季最重要的影响因子,水深是秋季最重要的影响因子。本研究在区域尺度上解析了海州湾矛尾虾虎鱼的空间分布特征及其分布重心的变化,并探讨了影响因子重要性的季节差异,可为海州湾矛尾虾虎鱼资源的可持续利用提供参考依据。展开更多
Vultures provide invaluable ecosystem services and play an important role in ecosystem balancing. The number of native vultures in India has declined in the past. Acquiring present knowledge of their habitat spread is...Vultures provide invaluable ecosystem services and play an important role in ecosystem balancing. The number of native vultures in India has declined in the past. Acquiring present knowledge of their habitat spread is essential to manage and prevent such a decline. It is envisaged that ongoing climate crisis may further cause change in habitat suitability and impact the existing population. Therefore, this study in Central India—a vulture stronghold, is aimed at predicting habitat changes in the short and long term and present the data statistically and graphically by using Species Distribution Model. MaxEnt software was chosen for its advantages over other models, like using presence-only data and performing well with incomplete data, small sample sizes and gaps, etc. Global Climate Model ensemble(CCSM4, HadGEM2 AO and MIROC5), was used to get better prediction. Fourteen robust models(AUC 0.864 0.892) were developed using data from over 1000 locations of seven vulture species over two seasons together. Selected climatic and other environmental variables were used to predict the current habitat. Future prediction was based on climatic variables only. The most important variables influencing the distribution were precipitation(bio 15, bio 18, bio 19) and temperature(bio 3, bio 5). Forest and water bodies were the major influencers within land use-landcover in the current prediction. At finer scale, while extremely suitable habitat area decreased and highly suitable area increased over time, the total suitable area marginally increased in 2050 but decreased in 2070. For broader consideration, net loss in suitable area was 5% in 2050 and 7.17% in 2070(RCP4.5). Similarly, in the RCP8.5 this was 6% in 2050 and 7.3% in 2070. The data generated can be used in conservation planning and management and thus protecting the vultures from any future threat.展开更多
We investigated the effects of climate change on the distribution of the Asiatic ibex(Capra sibirica)in eastern Tajikistan.No existing climate change studies have been conducted on the habitat of a wild goat species i...We investigated the effects of climate change on the distribution of the Asiatic ibex(Capra sibirica)in eastern Tajikistan.No existing climate change studies have been conducted on the habitat of a wild goat species in Asia.We conducted ecological niche modelling to compare potential present and future distributions of suitable environmental conditions for ibex.Projecting to 2070,18%(2689 km^2)of the current suitable areas would be lost,mostly located in the southeastern and northwestern regions of the study area.However,new suitable habitats could expand outside the current ibex range—about 30%(4595 km^2)expansion until 2070.We found that the elevation,terrain roughness,seasonal temperature,and precipitation of warmest quarter were the most important factors in the models and had strong correlations to ibex distribution.The losses in the southeastern portion overlapped most of the current locations of ibex in that region.These losses were observed in the much lower elevations of the study area(3500 m to 4000 m).When considering both loss and gain,the ibex could see a net expansion to new suitable habitats.About 30%(1379 km^2)of the average habitat gains for the Asiatic ibex in 2070 showed a shift to northern lower temperature habitats.Our results are beneficial in planning for the potential effects on biodiversity conservation in the eastern mountain region of Tajikistan under climate change scenarios.Special attention should be given to the ibex populations in the southeastern region,where habitats could become unsuitable for the species as a result of the climate-induced effects on the mountain ecosystem.展开更多
文摘为了应对近海渔业资源日益衰退的问题,为实施基于空间的渔业管理提供必要信息,以江苏南部海域小黄鱼为研究对象,根据2019—2022年在该海域进行的季节性渔业资源综合调查,结合5个生物和非生物因子,采用组合物种分布模型(Ensemble species distribution model,ESDM),研究了该海域小黄鱼的空间分布特征及其主要影响因素。结果显示,相较于单一物种分布模型,组合物种分布模型具有更高的AUC值(春季:0.995±0.002;秋季:0.985±0.001)和TSS值(春季:0.935±0.038;秋季:0.903±0.029)。在春季,底层水温和底层盐度的重要性水平最高(0.40和0.38),而在秋季叶绿素a和饵料生物丰度对小黄鱼空间分布的影响较大,其重要性分别为0.53和0.46。春季小黄鱼主要分布在近岸浅海区域,整体呈条带状分布;秋季小黄鱼则主要分布于水深较深的远岸水域,且适宜分布的海域范围要大于春季,整体呈块状分布。此外,小黄鱼的空间分布特征亦呈现出明显的年际差异,例如在2021年,其适宜栖息地面积明显小于其他年份,分布范围也仅限于局部区域。研究表明,组合物种分布模型具有更优的预测性能,能够更好地反映小黄鱼的栖息分布特征及其影响因素;不同季节小黄鱼的适生区及影响因素各有差异。本研究可为揭示该海域小黄鱼的时空分布特征及其变化规律提供理论依据,为实施基于空间的渔业管理和保护区选划提供基础资料。
文摘物种的空间分布能够反映个体在空间上的相互关系,是物种与环境长期适应和选择的结果,对物种的生长发育和资源利用等都具有显著影响。本研究基于2013—2022年春季和秋季在海州湾及其邻近海域进行的底拖网调查数据,构建了10种单一物种分布模型(species distribution model,SDM),结合真实技巧统计值(true skill statistic,TSS)和受试者工作特征曲线下面积值(area under ROCcurve,AUC)筛选预测精度和准确性较优的模型作为基础模型,并通过加权的方法分别构建不同季节的组合物种分布模型(ensemble species distribution model,ESDM),以解析矛尾虾虎鱼(Chaeturichthys stigmatias)的空间分布特征及其影响因素。结果表明,ESDM能够有效降低单一模型预测的不确定性,提高模型预测的精度,更加准确地解析海州湾矛尾虾虎鱼的空间分布特征。2013—2022年春季,矛尾虾虎鱼集中分布于海州湾西部近岸和南部海域,东部和中北部海域分布较少,分布重心的经度和纬度偏移范围大约为1°;秋季主要分布于海州湾西南部海域,分布重心呈辐射状小幅度移动。本研究发现,与矛尾虾虎鱼空间分布存在显著相关的影响因子为水深、饵料丰度、底层水温和底层盐度,其中饵料丰度是春季最重要的影响因子,水深是秋季最重要的影响因子。本研究在区域尺度上解析了海州湾矛尾虾虎鱼的空间分布特征及其分布重心的变化,并探讨了影响因子重要性的季节差异,可为海州湾矛尾虾虎鱼资源的可持续利用提供参考依据。
文摘Vultures provide invaluable ecosystem services and play an important role in ecosystem balancing. The number of native vultures in India has declined in the past. Acquiring present knowledge of their habitat spread is essential to manage and prevent such a decline. It is envisaged that ongoing climate crisis may further cause change in habitat suitability and impact the existing population. Therefore, this study in Central India—a vulture stronghold, is aimed at predicting habitat changes in the short and long term and present the data statistically and graphically by using Species Distribution Model. MaxEnt software was chosen for its advantages over other models, like using presence-only data and performing well with incomplete data, small sample sizes and gaps, etc. Global Climate Model ensemble(CCSM4, HadGEM2 AO and MIROC5), was used to get better prediction. Fourteen robust models(AUC 0.864 0.892) were developed using data from over 1000 locations of seven vulture species over two seasons together. Selected climatic and other environmental variables were used to predict the current habitat. Future prediction was based on climatic variables only. The most important variables influencing the distribution were precipitation(bio 15, bio 18, bio 19) and temperature(bio 3, bio 5). Forest and water bodies were the major influencers within land use-landcover in the current prediction. At finer scale, while extremely suitable habitat area decreased and highly suitable area increased over time, the total suitable area marginally increased in 2050 but decreased in 2070. For broader consideration, net loss in suitable area was 5% in 2050 and 7.17% in 2070(RCP4.5). Similarly, in the RCP8.5 this was 6% in 2050 and 7.3% in 2070. The data generated can be used in conservation planning and management and thus protecting the vultures from any future threat.
基金The Safari Club International Foundation(SCIF)The Federal Government of Germany via Deutsche Gesellschaft für Internationale Zusammenarbeit Gmb H(3393)
文摘We investigated the effects of climate change on the distribution of the Asiatic ibex(Capra sibirica)in eastern Tajikistan.No existing climate change studies have been conducted on the habitat of a wild goat species in Asia.We conducted ecological niche modelling to compare potential present and future distributions of suitable environmental conditions for ibex.Projecting to 2070,18%(2689 km^2)of the current suitable areas would be lost,mostly located in the southeastern and northwestern regions of the study area.However,new suitable habitats could expand outside the current ibex range—about 30%(4595 km^2)expansion until 2070.We found that the elevation,terrain roughness,seasonal temperature,and precipitation of warmest quarter were the most important factors in the models and had strong correlations to ibex distribution.The losses in the southeastern portion overlapped most of the current locations of ibex in that region.These losses were observed in the much lower elevations of the study area(3500 m to 4000 m).When considering both loss and gain,the ibex could see a net expansion to new suitable habitats.About 30%(1379 km^2)of the average habitat gains for the Asiatic ibex in 2070 showed a shift to northern lower temperature habitats.Our results are beneficial in planning for the potential effects on biodiversity conservation in the eastern mountain region of Tajikistan under climate change scenarios.Special attention should be given to the ibex populations in the southeastern region,where habitats could become unsuitable for the species as a result of the climate-induced effects on the mountain ecosystem.
