Analyzing and measuring the spatial distribution pattern of human settlement environment suitability in Beichuan County China is of great significance for optimizing population distribution and promoting human develop...Analyzing and measuring the spatial distribution pattern of human settlement environment suitability in Beichuan County China is of great significance for optimizing population distribution and promoting human development and environmental protection. Based on the DEM data and other data of Beichuan County, this paper uses GIS and ENVI software to extract four spatial distribution data of vegetation coverage index, topographic relief, hydrological index and natural disaster risk, and the spatial distribution pattern of natural suitability of human settlement environment in Beichuan County was obtained through overlay analysis. The results show: 1) Most of the areas with small topographic relief are located in the southeast of the study area, which is New Beichuan County and Anchang Town and Yong’an Town. The vegetation coverage index in the eastern region is higher, while the vegetation coverage index in the western and other high altitude regions is lower because there are more grasslands. 2) From the perspective of spatial distribution, Beichuan County as a whole is rich in water resources in the central and eastern part of the county, while the west is short of water resources;Chenjiaba Township, Guixi Town and Old Beichuan County are located on the fault zone with high natural disaster risk, the natural disaster risk is high in Piankou Township and Xiaoba Town and Kaiping Township Area. 3) The human settlement environment index of Beichuan county is 19.72 - 85.25;The natural suitability is the highest in the southeast, followed by the central and western regions, and the worst is located in the Piankou-Xiaoba and Old Beichuan-Guixi fault zones. 4) The general suitable area in Beichuan County is the largest, accounting for 30.4% of the total area of the study area. More suitable area ranked second, accounting for 29.33%;critical fitness suitable area accounted for 17.87%;the area of suitable highly suitable area accounted for 14.06%, and the unsuitable area accounted for 8.32%. Reasonable and efficient development and use of local resources is an inevitable way for the sustainable development of Beichuan County.展开更多
The Niger Delta region has witnessed environmental impacts arising from oil production activities. Soil fertility in these areas and the entire marine habitat was investigated based on the re-occurring spill incidents...The Niger Delta region has witnessed environmental impacts arising from oil production activities. Soil fertility in these areas and the entire marine habitat was investigated based on the re-occurring spill incidents in the area to establish the consequences of oil pollution on key performance indicators as well as the remedial actions for resuscitation. One of the bases of evaluation was on the fertility profile of the area impacted by oil spills as compared with the areas without oil spills influence. A suitable cost effective and environmentally friendly technique to handle the pollutions in the Niger Delta region can be found in systematic containment, recovery, clean up and restoration of the marine habitat to its initial capacity and status to be able to sustain life once again.展开更多
In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the ...In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the technical guidelines were proposed in 2006 are analyzed.Then,combined with projects and experience from 2006 to 2014,the four main issues are summarized:(1) There exist many questions in the design and construction of fishways,which are useful for fish migration,and the migration effects are not as expected.(2) Temperature stratification affecting the downstream fish is the major impact of temperature,and alters fish spawning in the reproduction season.(3)Ecological base flow has been one of the primary questions of the last 30 years in China,the greatest related difficulty being quantification of the amount and flow process necessary to satisfy fish life history.(4) Fish habitat protection and restoration are popular topics in recent years with the development of river ecosystem restoration.Fish habitat loss due to the impacts of dam construction and habitat fragmentation has become more and more serious.These four issues are now the main difficulties in water project management,and interact with one another to bear combined effects on river ecosystems.The issues of eco-hydraulic consideration in the design period are the key factors.Finally,future priorities for research and practice of environmental protection for water conservancy and hydropower projects in China are proposed.The main purpose of this paper is to enhance the scientific research,monitoring,and assessment of operating effectiveness.展开更多
Species-habitat association analysis is useful to detect spatial arrangement of individual plants, to discover rules about the distribution of species and to generate hypotheses about the possible underlying process c...Species-habitat association analysis is useful to detect spatial arrangement of individual plants, to discover rules about the distribution of species and to generate hypotheses about the possible underlying process controlling observed structures. Quantifying methods were used to classify habitats in terms of topographical variables in a mixed temperate broad-leaved Korean pine forest of the Changbai mountains in northeastern China. All of the 625 20 m × 20 m quadrats of the plot could be unambiguously assigned to one of three habitat categories （low-plateau, high-plateau and slope）. Torus-translation tests were used to estimate species-habitat associations. Many species are clearly distributed in a biased fashion with respect to habitats. Fifteen （55.6%） out of 27 species showed strong positive or negative association with specific habitats. We compared species-habitat associations at the sapling and adult stages. Adjusted density values indicated few species exhibit extremely strong habitat associations. Only 9 out of 26 species had adjusted densities 〉 3 in the habitat for which they had strong positive affinity. Few species show the same associations at the small tree and large tree stages. Only 3 out of 22 occurring associations with a specific habitat appeared to have a consistent habitat association at the two stages. These results suggest that species-habitat associations exist in the 25-ha plot of the temperate forest of the Chang- bai mountains. Owing to limitations in our statistical methodology, we partly underestimated associations by ignoring rare species. Regeneration niches can contribute to co-existence, but regeneration niches due to habitat associations play a limited role in species co-existence, since most species show a similar trend in habitat associations at the sapling and adult stages. We should pay more attention to shifts in habitat associations, i.e. niche shifts at different stages of existence.展开更多
Massive geological landslides and unstable landslide areas were triggered by the 2008 Wenchuan earthquake. These landslides caused deaths, damaged infrastructure and threatened endanger species. This study analyzed th...Massive geological landslides and unstable landslide areas were triggered by the 2008 Wenchuan earthquake. These landslides caused deaths, damaged infrastructure and threatened endanger species. This study analyzed the impact of landslides on giant pandas and their habitats from the following aspects: threatening pandas‘ lives, damaging pandas‘ habitat, influencing giant panda behavior, increasing habitat fragmentation; the final aspect, and blocking gene flow by cutting off corridors. A habitat suitability map was created by integrating the landslide factors with other traditional factors based on a logistics regression method. According to the landslide inventory map, there are 1313 landslides, 818 rock debris flows, 117 rock avalanches and 43 mud flows occurred in the study area. A correlation analysis indicated that landslides caused the pandas to migrate, and the core landslides within 1 km2 had greater influence on panda migration. These core landslides primarily occurred in mid-altitude regionscharacterized by high slopes, old geological ages, large areas and large rock mass volumes. The habitat suitability assessment results for the Wolong Natural Reserve had better prediction performance(80.9%) and demonstrated that 14.5%, 15.9%, 20.5%, 47.6% and 1.5% of the study area can be classified as very high, high, moderate, low and very low giant panda suitability areas, respectively. This study can be used to inform panda and panda habitat research, management and protection during post-quake reconstruction and recovery periods in China.展开更多
文摘Analyzing and measuring the spatial distribution pattern of human settlement environment suitability in Beichuan County China is of great significance for optimizing population distribution and promoting human development and environmental protection. Based on the DEM data and other data of Beichuan County, this paper uses GIS and ENVI software to extract four spatial distribution data of vegetation coverage index, topographic relief, hydrological index and natural disaster risk, and the spatial distribution pattern of natural suitability of human settlement environment in Beichuan County was obtained through overlay analysis. The results show: 1) Most of the areas with small topographic relief are located in the southeast of the study area, which is New Beichuan County and Anchang Town and Yong’an Town. The vegetation coverage index in the eastern region is higher, while the vegetation coverage index in the western and other high altitude regions is lower because there are more grasslands. 2) From the perspective of spatial distribution, Beichuan County as a whole is rich in water resources in the central and eastern part of the county, while the west is short of water resources;Chenjiaba Township, Guixi Town and Old Beichuan County are located on the fault zone with high natural disaster risk, the natural disaster risk is high in Piankou Township and Xiaoba Town and Kaiping Township Area. 3) The human settlement environment index of Beichuan county is 19.72 - 85.25;The natural suitability is the highest in the southeast, followed by the central and western regions, and the worst is located in the Piankou-Xiaoba and Old Beichuan-Guixi fault zones. 4) The general suitable area in Beichuan County is the largest, accounting for 30.4% of the total area of the study area. More suitable area ranked second, accounting for 29.33%;critical fitness suitable area accounted for 17.87%;the area of suitable highly suitable area accounted for 14.06%, and the unsuitable area accounted for 8.32%. Reasonable and efficient development and use of local resources is an inevitable way for the sustainable development of Beichuan County.
文摘The Niger Delta region has witnessed environmental impacts arising from oil production activities. Soil fertility in these areas and the entire marine habitat was investigated based on the re-occurring spill incidents in the area to establish the consequences of oil pollution on key performance indicators as well as the remedial actions for resuscitation. One of the bases of evaluation was on the fertility profile of the area impacted by oil spills as compared with the areas without oil spills influence. A suitable cost effective and environmentally friendly technique to handle the pollutions in the Niger Delta region can be found in systematic containment, recovery, clean up and restoration of the marine habitat to its initial capacity and status to be able to sustain life once again.
基金supported by a General Financial Grant from the China Postdoctoral Science Foundation(Grant No.2016M592404)the projects funded by the China Three Gorges Corporation(Grants No.0799556 and0799564)
文摘In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the technical guidelines were proposed in 2006 are analyzed.Then,combined with projects and experience from 2006 to 2014,the four main issues are summarized:(1) There exist many questions in the design and construction of fishways,which are useful for fish migration,and the migration effects are not as expected.(2) Temperature stratification affecting the downstream fish is the major impact of temperature,and alters fish spawning in the reproduction season.(3)Ecological base flow has been one of the primary questions of the last 30 years in China,the greatest related difficulty being quantification of the amount and flow process necessary to satisfy fish life history.(4) Fish habitat protection and restoration are popular topics in recent years with the development of river ecosystem restoration.Fish habitat loss due to the impacts of dam construction and habitat fragmentation has become more and more serious.These four issues are now the main difficulties in water project management,and interact with one another to bear combined effects on river ecosystems.The issues of eco-hydraulic consideration in the design period are the key factors.Finally,future priorities for research and practice of environmental protection for water conservancy and hydropower projects in China are proposed.The main purpose of this paper is to enhance the scientific research,monitoring,and assessment of operating effectiveness.
基金supported by the National Natural Science Foundation of China (Grant Nos. 30570306, 30870400 and 40971286)the Public Benefit Research Foun- dation of State Forestry Administration, China (No. 201104040)
文摘Species-habitat association analysis is useful to detect spatial arrangement of individual plants, to discover rules about the distribution of species and to generate hypotheses about the possible underlying process controlling observed structures. Quantifying methods were used to classify habitats in terms of topographical variables in a mixed temperate broad-leaved Korean pine forest of the Changbai mountains in northeastern China. All of the 625 20 m × 20 m quadrats of the plot could be unambiguously assigned to one of three habitat categories （low-plateau, high-plateau and slope）. Torus-translation tests were used to estimate species-habitat associations. Many species are clearly distributed in a biased fashion with respect to habitats. Fifteen （55.6%） out of 27 species showed strong positive or negative association with specific habitats. We compared species-habitat associations at the sapling and adult stages. Adjusted density values indicated few species exhibit extremely strong habitat associations. Only 9 out of 26 species had adjusted densities 〉 3 in the habitat for which they had strong positive affinity. Few species show the same associations at the small tree and large tree stages. Only 3 out of 22 occurring associations with a specific habitat appeared to have a consistent habitat association at the two stages. These results suggest that species-habitat associations exist in the 25-ha plot of the temperate forest of the Chang- bai mountains. Owing to limitations in our statistical methodology, we partly underestimated associations by ignoring rare species. Regeneration niches can contribute to co-existence, but regeneration niches due to habitat associations play a limited role in species co-existence, since most species show a similar trend in habitat associations at the sapling and adult stages. We should pay more attention to shifts in habitat associations, i.e. niche shifts at different stages of existence.
基金supported by program of international S&T Cooperation"Fined Earth Observation and Recognition of The Impact of the Global Change of on World Heritage Sites"(Grant No.2013DFG21640)Open Fund of the center for Earth observation and Digital Earth,the Chinese Academy of Sciences(Grant No.2013LDE006)
文摘Massive geological landslides and unstable landslide areas were triggered by the 2008 Wenchuan earthquake. These landslides caused deaths, damaged infrastructure and threatened endanger species. This study analyzed the impact of landslides on giant pandas and their habitats from the following aspects: threatening pandas‘ lives, damaging pandas‘ habitat, influencing giant panda behavior, increasing habitat fragmentation; the final aspect, and blocking gene flow by cutting off corridors. A habitat suitability map was created by integrating the landslide factors with other traditional factors based on a logistics regression method. According to the landslide inventory map, there are 1313 landslides, 818 rock debris flows, 117 rock avalanches and 43 mud flows occurred in the study area. A correlation analysis indicated that landslides caused the pandas to migrate, and the core landslides within 1 km2 had greater influence on panda migration. These core landslides primarily occurred in mid-altitude regionscharacterized by high slopes, old geological ages, large areas and large rock mass volumes. The habitat suitability assessment results for the Wolong Natural Reserve had better prediction performance(80.9%) and demonstrated that 14.5%, 15.9%, 20.5%, 47.6% and 1.5% of the study area can be classified as very high, high, moderate, low and very low giant panda suitability areas, respectively. This study can be used to inform panda and panda habitat research, management and protection during post-quake reconstruction and recovery periods in China.
