Sixteen different vegetation types of grassland and shrubland were selected to study the component and diversity of plant species of riparian plant communities along main channel in the Three-Gorges areas. Species ric...Sixteen different vegetation types of grassland and shrubland were selected to study the component and diversity of plant species of riparian plant communities along main channel in the Three-Gorges areas. Species richness (s), Simpson index (D), and Shannon-Weiner index (H) were used to study the biodiversity and the hierarchical classification was carried out by the methods of TWINSPAN and DCA ordination. The results showed that the components of flora were complex and dominated by the temperate type in the riparian plant communities. Species diversity was not different between the communities, but Shannon-Weiner indexes of different layers in some grassland were significantly different. TWINSPAN and DCA indicated that riparian plant communities distributed along the gradient of moisture.展开更多
The restoration of the riparian vegetation disturbed by human activities is one of the hotspots of watershed ecology. Through interpreting the images of Remote Sensing in 1985 and 1999, the basic information of forest...The restoration of the riparian vegetation disturbed by human activities is one of the hotspots of watershed ecology. Through interpreting the images of Remote Sensing in 1985 and 1999, the basic information of forest resources of Lushuihe Forest Bureau, which is a typical forest area of Changbai Mountain, was obtained with support of GIS. By dividing Land covers of Lushuihe area into 10 types (water body, residential land, stump land, farming land, wetland, mature conifer forest, midlife conifer forest, mature broadleaf forest, midlife broadleaf forest, and man-made young forest) and dividing the riparian zone into four buffers (in turn, 1000, 2000, 3000, 4000 m away from the river), the changes of riparian forest resources during 1985-1999 were analyzed. The results showed that the deforestation intension has obviously decreased and the whole environment has been evidently improved, but the riparian ecosystem was still flimsy. In buffer 1, 2, 3, the area of midlife conifer forest increased largely, but the areas of other types of land covers all decreased. Midlife conifer forest had a comparatively good status in the three buffers. In buffer 4, midlife conifer forest, mature conifer forest, and mature broadleaf forest formed a forest-age rank that is helpful to stabilize the forest ecosystem and exert its functions. Area percentage of wetland decreased in buffer 1, buffer 2, and buffer 3, even in buffer 4 in which forest ecosystem rehabilitated comparatively well, so protecting and rehabilitating wetland is a very difficult task.展开更多
This paper has examined how the resources of the White Volta River are enhancing food availability for riparian communities in northern Ghana despite climate change and its associated effects on food security. Using p...This paper has examined how the resources of the White Volta River are enhancing food availability for riparian communities in northern Ghana despite climate change and its associated effects on food security. Using participatory methods such as focus group discussions and interviews, data was collected from households and institutions in three riparian communities. The result of the study indicates that, all things been equal, cultivation of food crops along the river bank in the rainy season gives significantly high yields as compared to yields from farms farthest from the river under rain fed agriculture. Higher organic content and moisture retention capacity of river bank soils explains the yield differential and adaptability to climate change. In addition, farmers now irrigate cereal crops which were hitherto, reserved for only rainy season production. However, inappropriate irrigation practices are accelerating erosion and sedimentation of the river and thus, threaten the sustainability of agriculture and food security in the White Volta Basin. The paper therefore, recommends the adoption of IWRM （integrated water resources management） and the participation of local communities, Government and Civil Society organisations for sustaining the productive capacity of the White Volta Basin for enabling adaptation of agriculture to climate change in the riparian communities of the basin.展开更多
Due to federal, state, and local regulations pertaining to clean water and salmon recovery, stream health and water quality are major concerns in the Pacific Northwest of the United States. An integral component of mo...Due to federal, state, and local regulations pertaining to clean water and salmon recovery, stream health and water quality are major concerns in the Pacific Northwest of the United States. An integral component of most riparian rehabilitation efforts is the effective establishment of preferred vegetation. We conducted arthropod surveys in representative disturbed and rehabilitated riparian buffers directly adjacent to apple orchards and grape vineyards in the Lower Yakima Valley near Prosser, Benton County, Washington State USA. Objectives of the study were to determine whether densities of select predatory and pest taxa changed with distance from the waterway and to test whether densities differed among disturbed, rehabilitated, or pristine riparian buffers. The studies suggest that populations of some beneficial arthropods, including spiders and ground beetles, were higher in the presence of exotic flowering plant species. In the riparian environments surveyed, more native woody plant species were found adjacent to the waterway, and this apparent stability appears to have had a positive effect on beneficial arthropods. Concurrently, data indicated that some exotic, flowering species of plants may be preferred over native plant species as hosts to certain arthropod pests. These plants tend to persist in degraded riparian buffers and at the interface of riparian habitats and cultivated areas, whereas native plant species are predominant in pristine or properly maintained and rehabilitated buffers.展开更多
An investigation has been carried out in the vicinity of the coastal villages of Kanyakumari District,India to decode the influence of coastal geomorphology on inundation degree and run-up level.Even though the tsunam...An investigation has been carried out in the vicinity of the coastal villages of Kanyakumari District,India to decode the influence of coastal geomorphology on inundation degree and run-up level.Even though the tsunami waves approach the study area in different patterns,the consequences are found to be mainly dependent upon the coastal configuration and local geographic setting,the study area are considered to be of three types based upon the geomorphic arrangement,namely shallow coast,elevated coast and estuarine coast.The inundation and run-up level vary from coast to coast even though there is no remarkable variation in the intensity of the approaching tsunami surge.The inundation extent ranges from to 54 m to 413 m with maximum along estuarine coast and minimum along elevated coast.Estuarine coast recorded the maximum run-up level of about 6 m and the minimum of about 1 m along the elevated coast.The percentage of inundated area in the total coastal area varies between 19% to 10% along estuarine coast and elevated coast respectively.Inundation and run-up level cannot be appreciable in the inland along the elevated coast.The beaches of elevated coast are less affected whereas those of estuarine coast are highly affected.Inundation is limited in the elevated beaches along the study area.展开更多
Abstract： Because of the complex topography in southwest region of China, the water level of the inland river has a large amplitude of variation which causes a frequent diversification of water content in the river s...Abstract： Because of the complex topography in southwest region of China, the water level of the inland river has a large amplitude of variation which causes a frequent diversification of water content in the river slope. The flow caused by the infiltration of the terminal slope stability will induce a great impact on the slope stability of wharf.. This paper uses an ideal elastic-plastic model and the Moore Coulomb yield criterion for numerical simulation. Through the b an k slop e stability of the overhead-type terminal s under the changes of water, we obtained the impact of all factors on the bank slope in the course of water lowering. It was found out that the impact from the cohesion of the geo-materials of the bank slope on the slope stability is greater than that from the internal friction angle.展开更多
基金This study was supported by the Chinese Academy of Sciences (A grant KZCX2-406) the National Natural Science Foundation of China (NSFC39970123) and Changbai Mountain Open Research Station.
文摘Sixteen different vegetation types of grassland and shrubland were selected to study the component and diversity of plant species of riparian plant communities along main channel in the Three-Gorges areas. Species richness (s), Simpson index (D), and Shannon-Weiner index (H) were used to study the biodiversity and the hierarchical classification was carried out by the methods of TWINSPAN and DCA ordination. The results showed that the components of flora were complex and dominated by the temperate type in the riparian plant communities. Species diversity was not different between the communities, but Shannon-Weiner indexes of different layers in some grassland were significantly different. TWINSPAN and DCA indicated that riparian plant communities distributed along the gradient of moisture.
基金This study is supported by major projects of Knowledge Innovation Program Chinese Academy of Sciences ( No. KZCX2-SW-320-3) and Institute of Applied Ecology (a grant SCXZD010-01)CAS
文摘The restoration of the riparian vegetation disturbed by human activities is one of the hotspots of watershed ecology. Through interpreting the images of Remote Sensing in 1985 and 1999, the basic information of forest resources of Lushuihe Forest Bureau, which is a typical forest area of Changbai Mountain, was obtained with support of GIS. By dividing Land covers of Lushuihe area into 10 types (water body, residential land, stump land, farming land, wetland, mature conifer forest, midlife conifer forest, mature broadleaf forest, midlife broadleaf forest, and man-made young forest) and dividing the riparian zone into four buffers (in turn, 1000, 2000, 3000, 4000 m away from the river), the changes of riparian forest resources during 1985-1999 were analyzed. The results showed that the deforestation intension has obviously decreased and the whole environment has been evidently improved, but the riparian ecosystem was still flimsy. In buffer 1, 2, 3, the area of midlife conifer forest increased largely, but the areas of other types of land covers all decreased. Midlife conifer forest had a comparatively good status in the three buffers. In buffer 4, midlife conifer forest, mature conifer forest, and mature broadleaf forest formed a forest-age rank that is helpful to stabilize the forest ecosystem and exert its functions. Area percentage of wetland decreased in buffer 1, buffer 2, and buffer 3, even in buffer 4 in which forest ecosystem rehabilitated comparatively well, so protecting and rehabilitating wetland is a very difficult task.
文摘This paper has examined how the resources of the White Volta River are enhancing food availability for riparian communities in northern Ghana despite climate change and its associated effects on food security. Using participatory methods such as focus group discussions and interviews, data was collected from households and institutions in three riparian communities. The result of the study indicates that, all things been equal, cultivation of food crops along the river bank in the rainy season gives significantly high yields as compared to yields from farms farthest from the river under rain fed agriculture. Higher organic content and moisture retention capacity of river bank soils explains the yield differential and adaptability to climate change. In addition, farmers now irrigate cereal crops which were hitherto, reserved for only rainy season production. However, inappropriate irrigation practices are accelerating erosion and sedimentation of the river and thus, threaten the sustainability of agriculture and food security in the White Volta Basin. The paper therefore, recommends the adoption of IWRM （integrated water resources management） and the participation of local communities, Government and Civil Society organisations for sustaining the productive capacity of the White Volta Basin for enabling adaptation of agriculture to climate change in the riparian communities of the basin.
基金The authors would like thank S. Schveilbein and R. Wight for technical assistance G. Reisenauer and R. Aldridge for statistical assistance+2 种基金 B. Parker for plant identification assistance C. Looney for arthropod identification assistance and S. O＇Neal for editorial feedback. The authors are grateful to Olson Brothers Inc. for the use of their property. The authors would like to acknowledge the National Science Foundation Center for Integrated Pest Management, The Washington State Tree Fruit Research Commission, and the Washington State Commission on Pesticide Registration for financial support.
文摘Due to federal, state, and local regulations pertaining to clean water and salmon recovery, stream health and water quality are major concerns in the Pacific Northwest of the United States. An integral component of most riparian rehabilitation efforts is the effective establishment of preferred vegetation. We conducted arthropod surveys in representative disturbed and rehabilitated riparian buffers directly adjacent to apple orchards and grape vineyards in the Lower Yakima Valley near Prosser, Benton County, Washington State USA. Objectives of the study were to determine whether densities of select predatory and pest taxa changed with distance from the waterway and to test whether densities differed among disturbed, rehabilitated, or pristine riparian buffers. The studies suggest that populations of some beneficial arthropods, including spiders and ground beetles, were higher in the presence of exotic flowering plant species. In the riparian environments surveyed, more native woody plant species were found adjacent to the waterway, and this apparent stability appears to have had a positive effect on beneficial arthropods. Concurrently, data indicated that some exotic, flowering species of plants may be preferred over native plant species as hosts to certain arthropod pests. These plants tend to persist in degraded riparian buffers and at the interface of riparian habitats and cultivated areas, whereas native plant species are predominant in pristine or properly maintained and rehabilitated buffers.
基金the National Resource Data Management System (NRDMS) Division of the Department of Science and Technology (DST)Government of India for supplying the necessary equipment and financial assistance
文摘An investigation has been carried out in the vicinity of the coastal villages of Kanyakumari District,India to decode the influence of coastal geomorphology on inundation degree and run-up level.Even though the tsunami waves approach the study area in different patterns,the consequences are found to be mainly dependent upon the coastal configuration and local geographic setting,the study area are considered to be of three types based upon the geomorphic arrangement,namely shallow coast,elevated coast and estuarine coast.The inundation and run-up level vary from coast to coast even though there is no remarkable variation in the intensity of the approaching tsunami surge.The inundation extent ranges from to 54 m to 413 m with maximum along estuarine coast and minimum along elevated coast.Estuarine coast recorded the maximum run-up level of about 6 m and the minimum of about 1 m along the elevated coast.The percentage of inundated area in the total coastal area varies between 19% to 10% along estuarine coast and elevated coast respectively.Inundation and run-up level cannot be appreciable in the inland along the elevated coast.The beaches of elevated coast are less affected whereas those of estuarine coast are highly affected.Inundation is limited in the elevated beaches along the study area.
文摘Abstract： Because of the complex topography in southwest region of China, the water level of the inland river has a large amplitude of variation which causes a frequent diversification of water content in the river slope. The flow caused by the infiltration of the terminal slope stability will induce a great impact on the slope stability of wharf.. This paper uses an ideal elastic-plastic model and the Moore Coulomb yield criterion for numerical simulation. Through the b an k slop e stability of the overhead-type terminal s under the changes of water, we obtained the impact of all factors on the bank slope in the course of water lowering. It was found out that the impact from the cohesion of the geo-materials of the bank slope on the slope stability is greater than that from the internal friction angle.
