The Western Route of the South-to-North Water Transfer Project will divert water from the upper Yangtze River and its tributaries,the Dadu River and Yalong River,to the upper Yellow River.The project may ease the wate...The Western Route of the South-to-North Water Transfer Project will divert water from the upper Yangtze River and its tributaries,the Dadu River and Yalong River,to the upper Yellow River.The project may ease the water shortage in the Yellow River Basin.However,it may also have some effects on the ecosystem in the upper Yangtze River Basin.Benthic invertebrates play an important role in the river ecosystem,particularly in the circulation of materials and nutrition.Benthic invertebrates are widely used to quickly assess river ecosystems because of their rapid response to changes in the water environment.The diversity of benthic invertebrates is closely associated with the aquatic habitat area.This study examined this interaction by sampling the benthic invertebrates in an expanding area.The conclusions are that the diversity of benthic invertebrates begins to decrease when the aquatic habitat area is reduced to 45% of the original area,and decreases dramatically when the aquatic habitat area is reduced to 10% of the original area.The aquatic habitat area should be kept at more than 45% of the original area in order to maintain the significant diversity of benthic invertebrates.展开更多
Marine Protected Areas are increasingly becoming a tool of choice for conservation and management of marine resources and ecosystems. Data on biodiversity are necessary to assist in establishing protected areas for co...Marine Protected Areas are increasingly becoming a tool of choice for conservation and management of marine resources and ecosystems. Data on biodiversity are necessary to assist in establishing protected areas for conservation objectives to be met. Toward that effect, we investigated reef biodiversity patterns in three large-scale coastal regions of Brazil. The study areas comprised of an upwelling region, an adjacent high impacted region, and a more distant marine park. We surveyed four reef sites in each study region. Species counts of sessile benthic organisms, substrate relief, and average monthly water temperatures were recorded during the surveys. Benthic organisms were identified to the lowest taxa possible using still photos. Biodiversity was estimated using Shannon’s index on richness of organism taxa. Diversity was highest at the upwelling and high-impacted areas. No substrate relief patterns were found. Temperature readings showed lower average values at the upwelling and high impacted regions. Our results favor the upwelling region for establishment of a Marine Protected Area. Moreover, the similar diversity between the upwelling and the high impacted regions showed evidence of spillover effects from the former into the latter region, further demonstrating the importance of the former region for conservation.展开更多
Habitat fragmentation has been a research hotspot of biodiversity,and an important "bottleneck" restricting biodiversity.Habitat fragmentation can cause species loss and affect the process of immigration and...Habitat fragmentation has been a research hotspot of biodiversity,and an important "bottleneck" restricting biodiversity.Habitat fragmentation can cause species loss and affect the process of immigration and colonization by decreasing habitat size and increasing isolation degree among populations,thereby affecting species diversity of animals and plants.This paper elaborated the concept and main theory of habitat fragmentation and the influence of habitat fragmentation on species diversity of animals and plants,and suggested that studies on the effects of habitat fragmentation on species diversity at multi-trophic levels and larger scales should be strengthened.展开更多
River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is reco...River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA) using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.展开更多
为揭示并预测武陵山区土地利用与生境质量时空演变特征,基于2000、2010、2020年的土地利用数据,通过斑块生成土地利用模拟(patch-generating land use simulation,PLUS)模型和生态系统服务与权衡综合评估(integrated valuation of ecosy...为揭示并预测武陵山区土地利用与生境质量时空演变特征,基于2000、2010、2020年的土地利用数据,通过斑块生成土地利用模拟(patch-generating land use simulation,PLUS)模型和生态系统服务与权衡综合评估(integrated valuation of ecosystem services and trade-offs,InVEST)模型,模拟并分析武陵山区土地利用与生境质量时空演变特征。研究发现武陵山区主要地类为林地,耕地次之,2000-2020年土地利用变化呈“三减三增”的特点;2021-2030年土地利用变化将呈“一增多减”的特点,各地类的变化强度减弱。武陵山区生境质量较高且基本保持稳定,生境质量的高值区和低值区聚集分布;其中,高值区的生境是武陵山区的主要生境类型,不同生境质量等级的区域面积变化呈现“一增两减,两稳定”的特点。2000-2020年武陵山区中西部地区生境质量有所改善,北部和东南部的局部地区生境质量退化,2021-2030年生境质量整体将保持稳定。该研究可为武陵山区土地资源可持续利用和生境质量的提高提供科学依据和决策参考。展开更多
A groyne zone formed by installing groynes functions as habitat or shelter for aquatic organisms during a flood. Since flow characteristics over a groyne zone are affected directly by groynes, understanding flow patte...A groyne zone formed by installing groynes functions as habitat or shelter for aquatic organisms during a flood. Since flow characteristics over a groyne zone are affected directly by groynes, understanding flow patterns due to shapes and types of groynes is of importance for designing groynes. In order to use groynes as an eco-friendly river structure, the ecological effects should also be considered at the design stage. In Korea, the ecological effects of groynes have rarely been examined or included for the actual design. In this study, a set of experiments were carried out to investigate flow pattern changes depending on different types of groynes. Based on the flow characteristics in the groyne zone, the scales of habitats and shelters by the groyne types were estimated. In addition, to test the applicability of a habitat evaluation model to the ecological design of groynes, River2D was used for a virtual river. For assessment of the groyne’s function of ecological habitat, the suitability index of a habitat for pale chub, one of the popular fishes in Korea, was used and the habitat areas by the groyne types were analyzed. The flow changes depending on the groyne types simulated by River2D show the applicability for the simulation of an ecological habitat to the groyne design.展开更多
Background: Although the species-urban green area relationship (SARu) has been analyzed worldwide, the global consistency of its parameters, such as the fit and the slope of models, remains unexplored. Moreover,the SA...Background: Although the species-urban green area relationship (SARu) has been analyzed worldwide, the global consistency of its parameters, such as the fit and the slope of models, remains unexplored. Moreover,the SARu can be explained by 20 different models. Therefore, our objective was to evaluate which models provide a better explanation of SARus and, focusing on the power model,to evaluate the global heterogeneity in its fit and slope. Methods: We tested the performance of multiple statistical models in accounting for the way in which species richness increases with area, and examined whether variability in model form was associated with various methodological and environmental factors. Focusing on the power model, we analyzed the global heterogeneity in the fit and slope of the models through a meta-analysis. Results: Among 20 analyzed models, the linear model provided the best fit to the most datasets, was the top ranked model according to our efficiency criterion, and was the top overall ranked model.The Kobayashi and power models were the second and third overall ranked models, respectively.The number of green areas and the minimum number of species within a green area were the only significant variables explaining the variation in model form and performance, accounting for less than 10% of the variation. Based on the power model,there was a consistent overall fit (r2=0.50) and positive slope of 0.20 for the species richness increase with area worldwide.Conclusions:The good fit of the linear model to our SARu datasets contrasts with the non-linear SAR frequently found in true and non-urban habitat island systems;however, this finding may be a result of the small sample size of many SARu datasets. The overall power model slope of 0.20 suggests low levels of isolation among urban green patches, or alternatively that habitat specialist and area sensitive species have already been extirpated from urban green areas.展开更多
The field formed by groyne has the function of aquatic habitats for the underwater biology. The characteristic of groyne field occurring around downstream of groyne depends on groyne type and shape. Thus to maximize t...The field formed by groyne has the function of aquatic habitats for the underwater biology. The characteristic of groyne field occurring around downstream of groyne depends on groyne type and shape. Thus to maximize the function of groyne, it needs to understand the flow characteristic around groyne. In this study, experiment model test was conducted in recirculation zone located in downstream of groyne. Groyne types for experiment are three: permeable, impermeable and inclined crest groyne. LSPIV (Large Scale Particle Image Velocimetry) is used to measure flow field around the groyne and it revealed flow characteristic in recirculation zone at each case. In order to estimate the aquatic habitats of groyne fields, critical swimming speed of major fleshwater fish in Korea was compared with the variation of velocity distribution in groyne fields. From the results, the rate of velocity decreases in groyne fields, V/Vapp were measured to be 0 to 0.5 and the results can be fundamental data which are used to estimate the aquatic habitable function of groyne.展开更多
The pteridophytes comprising ferns and fern allies constitute an important part in Nepalese flora. Pteridophyte flora of the Himalayan region is considered to be the basic requirements for the knowledge of pteridology...The pteridophytes comprising ferns and fern allies constitute an important part in Nepalese flora. Pteridophyte flora of the Himalayan region is considered to be the basic requirements for the knowledge of pteridology. This paper aims to provide the overview of fern and fern allies present in the Nubri valley and its adjoining areas of Manaslu Conservation Area (MCA), Central Nepal. A total of 105 species belonging to 45 genera were recorded, with Dryopteris as the largest genera including twelve species followed by Athyrium, Pteris and Polystichum. With regard to habitats, most of the species were terrestrials followed by lithophytes and epiphytes.展开更多
As an introduction to the Special Issue on the restoration of threatened plant species and their habitats,this editorial shows how the various papers in the issue address the range of in situ interventions involved in...As an introduction to the Special Issue on the restoration of threatened plant species and their habitats,this editorial shows how the various papers in the issue address the range of in situ interventions involved in species population management and restoration of their habitat, together with examples of case studies implementing these actions. It stresses the need for integrating these various interventions.It highlights the importance of protected areas in providing a degree of protection for threatened species but also the need to complement this with actions at the species level to ensure the effective conservation and long term persistence of these species. It emphasizes that ecological restoration is a complement to, not a substitute for conservation, and that the balance of effort and allocation of resources between them is a key issue.展开更多
基金supported by the National Hi-Tech Research and Development Program of China ("863" Project) (Grant No. 2006BAB04A08)the National Natural Science Foundation of China (Grant No. 50779027)
文摘The Western Route of the South-to-North Water Transfer Project will divert water from the upper Yangtze River and its tributaries,the Dadu River and Yalong River,to the upper Yellow River.The project may ease the water shortage in the Yellow River Basin.However,it may also have some effects on the ecosystem in the upper Yangtze River Basin.Benthic invertebrates play an important role in the river ecosystem,particularly in the circulation of materials and nutrition.Benthic invertebrates are widely used to quickly assess river ecosystems because of their rapid response to changes in the water environment.The diversity of benthic invertebrates is closely associated with the aquatic habitat area.This study examined this interaction by sampling the benthic invertebrates in an expanding area.The conclusions are that the diversity of benthic invertebrates begins to decrease when the aquatic habitat area is reduced to 45% of the original area,and decreases dramatically when the aquatic habitat area is reduced to 10% of the original area.The aquatic habitat area should be kept at more than 45% of the original area in order to maintain the significant diversity of benthic invertebrates.
文摘Marine Protected Areas are increasingly becoming a tool of choice for conservation and management of marine resources and ecosystems. Data on biodiversity are necessary to assist in establishing protected areas for conservation objectives to be met. Toward that effect, we investigated reef biodiversity patterns in three large-scale coastal regions of Brazil. The study areas comprised of an upwelling region, an adjacent high impacted region, and a more distant marine park. We surveyed four reef sites in each study region. Species counts of sessile benthic organisms, substrate relief, and average monthly water temperatures were recorded during the surveys. Benthic organisms were identified to the lowest taxa possible using still photos. Biodiversity was estimated using Shannon’s index on richness of organism taxa. Diversity was highest at the upwelling and high-impacted areas. No substrate relief patterns were found. Temperature readings showed lower average values at the upwelling and high impacted regions. Our results favor the upwelling region for establishment of a Marine Protected Area. Moreover, the similar diversity between the upwelling and the high impacted regions showed evidence of spillover effects from the former into the latter region, further demonstrating the importance of the former region for conservation.
文摘Habitat fragmentation has been a research hotspot of biodiversity,and an important "bottleneck" restricting biodiversity.Habitat fragmentation can cause species loss and affect the process of immigration and colonization by decreasing habitat size and increasing isolation degree among populations,thereby affecting species diversity of animals and plants.This paper elaborated the concept and main theory of habitat fragmentation and the influence of habitat fragmentation on species diversity of animals and plants,and suggested that studies on the effects of habitat fragmentation on species diversity at multi-trophic levels and larger scales should be strengthened.
文摘River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA) using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.
文摘为揭示并预测武陵山区土地利用与生境质量时空演变特征,基于2000、2010、2020年的土地利用数据,通过斑块生成土地利用模拟(patch-generating land use simulation,PLUS)模型和生态系统服务与权衡综合评估(integrated valuation of ecosystem services and trade-offs,InVEST)模型,模拟并分析武陵山区土地利用与生境质量时空演变特征。研究发现武陵山区主要地类为林地,耕地次之,2000-2020年土地利用变化呈“三减三增”的特点;2021-2030年土地利用变化将呈“一增多减”的特点,各地类的变化强度减弱。武陵山区生境质量较高且基本保持稳定,生境质量的高值区和低值区聚集分布;其中,高值区的生境是武陵山区的主要生境类型,不同生境质量等级的区域面积变化呈现“一增两减,两稳定”的特点。2000-2020年武陵山区中西部地区生境质量有所改善,北部和东南部的局部地区生境质量退化,2021-2030年生境质量整体将保持稳定。该研究可为武陵山区土地资源可持续利用和生境质量的提高提供科学依据和决策参考。
文摘A groyne zone formed by installing groynes functions as habitat or shelter for aquatic organisms during a flood. Since flow characteristics over a groyne zone are affected directly by groynes, understanding flow patterns due to shapes and types of groynes is of importance for designing groynes. In order to use groynes as an eco-friendly river structure, the ecological effects should also be considered at the design stage. In Korea, the ecological effects of groynes have rarely been examined or included for the actual design. In this study, a set of experiments were carried out to investigate flow pattern changes depending on different types of groynes. Based on the flow characteristics in the groyne zone, the scales of habitats and shelters by the groyne types were estimated. In addition, to test the applicability of a habitat evaluation model to the ecological design of groynes, River2D was used for a virtual river. For assessment of the groyne’s function of ecological habitat, the suitability index of a habitat for pale chub, one of the popular fishes in Korea, was used and the habitat areas by the groyne types were analyzed. The flow changes depending on the groyne types simulated by River2D show the applicability for the simulation of an ecological habitat to the groyne design.
基金funded by the Consejo Nacional de Investigaciones Científicas y Técnicas and the Universidad de Buenos Aires (Argentina)
文摘Background: Although the species-urban green area relationship (SARu) has been analyzed worldwide, the global consistency of its parameters, such as the fit and the slope of models, remains unexplored. Moreover,the SARu can be explained by 20 different models. Therefore, our objective was to evaluate which models provide a better explanation of SARus and, focusing on the power model,to evaluate the global heterogeneity in its fit and slope. Methods: We tested the performance of multiple statistical models in accounting for the way in which species richness increases with area, and examined whether variability in model form was associated with various methodological and environmental factors. Focusing on the power model, we analyzed the global heterogeneity in the fit and slope of the models through a meta-analysis. Results: Among 20 analyzed models, the linear model provided the best fit to the most datasets, was the top ranked model according to our efficiency criterion, and was the top overall ranked model.The Kobayashi and power models were the second and third overall ranked models, respectively.The number of green areas and the minimum number of species within a green area were the only significant variables explaining the variation in model form and performance, accounting for less than 10% of the variation. Based on the power model,there was a consistent overall fit (r2=0.50) and positive slope of 0.20 for the species richness increase with area worldwide.Conclusions:The good fit of the linear model to our SARu datasets contrasts with the non-linear SAR frequently found in true and non-urban habitat island systems;however, this finding may be a result of the small sample size of many SARu datasets. The overall power model slope of 0.20 suggests low levels of isolation among urban green patches, or alternatively that habitat specialist and area sensitive species have already been extirpated from urban green areas.
文摘The field formed by groyne has the function of aquatic habitats for the underwater biology. The characteristic of groyne field occurring around downstream of groyne depends on groyne type and shape. Thus to maximize the function of groyne, it needs to understand the flow characteristic around groyne. In this study, experiment model test was conducted in recirculation zone located in downstream of groyne. Groyne types for experiment are three: permeable, impermeable and inclined crest groyne. LSPIV (Large Scale Particle Image Velocimetry) is used to measure flow field around the groyne and it revealed flow characteristic in recirculation zone at each case. In order to estimate the aquatic habitats of groyne fields, critical swimming speed of major fleshwater fish in Korea was compared with the variation of velocity distribution in groyne fields. From the results, the rate of velocity decreases in groyne fields, V/Vapp were measured to be 0 to 0.5 and the results can be fundamental data which are used to estimate the aquatic habitable function of groyne.
文摘The pteridophytes comprising ferns and fern allies constitute an important part in Nepalese flora. Pteridophyte flora of the Himalayan region is considered to be the basic requirements for the knowledge of pteridology. This paper aims to provide the overview of fern and fern allies present in the Nubri valley and its adjoining areas of Manaslu Conservation Area (MCA), Central Nepal. A total of 105 species belonging to 45 genera were recorded, with Dryopteris as the largest genera including twelve species followed by Athyrium, Pteris and Polystichum. With regard to habitats, most of the species were terrestrials followed by lithophytes and epiphytes.
文摘As an introduction to the Special Issue on the restoration of threatened plant species and their habitats,this editorial shows how the various papers in the issue address the range of in situ interventions involved in species population management and restoration of their habitat, together with examples of case studies implementing these actions. It stresses the need for integrating these various interventions.It highlights the importance of protected areas in providing a degree of protection for threatened species but also the need to complement this with actions at the species level to ensure the effective conservation and long term persistence of these species. It emphasizes that ecological restoration is a complement to, not a substitute for conservation, and that the balance of effort and allocation of resources between them is a key issue.
