Urban growth is a key indicator of economic development.At the same time,haphazard urban growth creates serious socioeconomic,environmental and urban land management problems.In this context,understanding the process ...Urban growth is a key indicator of economic development.At the same time,haphazard urban growth creates serious socioeconomic,environmental and urban land management problems.In this context,understanding the process of urban landscape change is important for guiding the sustainable growth of urban areas.This study analyzes the urban land changes during 1990–2018 in two metropolitan cities of Gandaki basin:Pokhara and Bharatpur.Landsat satellite images were analyzed using supervised classification methods.The results revealed that the built-up area has increased significantly by 300%in Pokhara and by nearly 500%in the Bharatpur during the past 28 years.Population growth,migration from surrounding areas due to urban facilities and the easy lifestyle in cities were found to be major determinants of urban growth within the study area.In addition,the changing urban definition and expansion of municipal boundaries are key factors for rapid urban growth.Both cities are likely to grow in the future as they are both located in areas that encompass the high levels of commercial activity and modern service facilities.The haphazard urban growth should be minimized through planning and policies for sustainable urban development.展开更多
In its upper and middle course, the Kali Gandaki river in Western Nepal flows across the Himalayan ranges more or less following tectonic lineaments (NNE—SSW). In this paper we focus our attention on certain slope de...In its upper and middle course, the Kali Gandaki river in Western Nepal flows across the Himalayan ranges more or less following tectonic lineaments (NNE—SSW). In this paper we focus our attention on certain slope deformations along the valley flanks of the middle course, especially on very narrow sections of this large transverse valley. Although the valley experienced several Pleistocene periods of strong glaciations and the powerful river flowing through it currently ranks as the second largest in Nepal we find a number of those amazing valley constrictions in the studied area which should not be ascribed to differences in rock resistance against erosion or to active tectonic control. It can best be explained by deep\|seated rock creep (Chigira,1992), a process which is frequently connected with landslides or rockfalls and must have developed during late Pleistocene and Holocene, i.e. since the valley was deglaciated. In order to prove this thesis we shall describe the situation by means of three case studies between the villages of Rukse (upstream) and Beni (downstream). Another fourth example of gravitational slope deformation described in this paper is located downstream of the reach of previous valley glaciations. Here, too, deep\|seated rock creep is considered to be responsible for the observed mass movements and thus for slope deformation.展开更多
The Gandaki River Basin(GRB),located in the central Himalaya,provides habitats for a large number of important flora and fauna species.The habitats of key protected species have changed over time as a result of climat...The Gandaki River Basin(GRB),located in the central Himalaya,provides habitats for a large number of important flora and fauna species.The habitats of key protected species have changed over time as a result of climate changes and human activities related to land use change,including the development of roads.This study assessed the present and future distributions of sloth bear(Melursus ursinus)habitats using the maximum entropy(Max Ent)model.Bioclimatic data,a digital elevation model and roads were used as environmental layers to assess current and future distributions of habitat.Results show that the overall habitat within the study area is likely to undergo important changes in the future.Bio 8(the mean temperature of the wettest quarter)and slope were found to be important variables affecting the distribution of the species.The habitats very highly suitable for sloth bears currently cover an area of 148 km^(2) within the GRB.These habitats are predicted to increase by 122 km^(2) more by 2050.Overall,a net change by 680.38 km^(2) was found in the GRB.Conservation measures are necessary for this key protected species and its habitat within the GRB and elsewhere in Nepal.展开更多
Gandaki River Basin(GRB) is part of the central Himalayan region, which provides habitat for numerous wild species. However, due to changes in climate and land cover, the habitats of many protected species are at risk...Gandaki River Basin(GRB) is part of the central Himalayan region, which provides habitat for numerous wild species. However, due to changes in climate and land cover, the habitats of many protected species are at risk. Based on the maximum entropy(MaxEnt) model, coupled with bioclimatic layers, land cover and DEM data, the impacts of environmental factors on habitat suitability of Himalayan Monal(Lophophorus impejanus), a national bird of Nepal, was quantified. This study further assessed the present and future habitat and distribution of the Himalayan Monal in the context of climate and land cover changes. The results of this study show that the highly suitable habitat of Himalayan Monal presently occupies around 749 km^2 within the northern, eastern and western parts, particularly protected areas such as Langtang National Park, Manaslu Conservation Area and Annapurna Conservation Area, while it is likely to decrease to 561 km^2 by 2050, primarily in the northern and northwestern parts(i.e., Chhyo, Tatopani, Humde and Chame). These expected changes indicate increasing risk for Himalayan Monal due to a decline in its suitable habitat area.展开更多
Gandaki River Basin(GRB)is an important part of the central Himalayan region,which provides habitat for numerous wild species.However,climatic changes are making the habitat in this basin more vulnerable.This paper ai...Gandaki River Basin(GRB)is an important part of the central Himalayan region,which provides habitat for numerous wild species.However,climatic changes are making the habitat in this basin more vulnerable.This paper aims to assess the potential impacts of climate change on the spatial distributions of habitat changes for two vulnerable species,Himalayan black bear(Ursus thibetanus laniger)and common leopard(Panthera pardus fusca),using the maximum entropy(Max Ent)species distribution model.Species occurrence locations were used along with several bioclimatic and topographic variables(elevation,slope and aspect)to fit the model and predict the potential distributions(current and future)of the species.The results show that the highly suitable area of Himalayan black bear within the GRB currently encompasses around 1642 km^(2)(5.01%area of the basin),which is predicted to increase by 51 km^(2) in the future(2050).Similarly,the habitat of common leopard is estimated as 3999 km^(2)(12.19%of the GRB area),which is likely to increase to 4806 km^(2) in 2050.Spatially,the habitat of Himalayan black bear is predicted to increase in the eastern part(Baseri,Tatopani and north from Bhainse)and to decrease in the eastern(Somdang,Chhekampar),western(Burtibang and Bobang)and northern(Sangboche,Manang,Chhekampar)parts of the study area.Similarly,the habitat of common leopard is projected to decrease particularly in the eastern,western and southern parts of the basin,although it is estimated to be extended in the southeastern(Bhainse),western(Harichaur and northern Sandhikhark)and north-western(Sangboche)parts of the basin.To determine the habitat impact,the environmental variables such as elevation,Bio 15(precipitation seasonality)and Bio 16(precipitation of wettest quarter)highly contribute to habitat change of Himalayan black bear;while Bio 13(precipitation of wettest month)and Bio 15 are the main contributors for common leopard.Overall,this study predicted that the suitable habitat areas of both species are likely to be impacte展开更多
This research examines flood events and related human interactions in the northwestern Himalayan Buri Gandaki Valley(Nepal). Past flood events that left traces at elevations between 3745 m to 780 m above sea level wer...This research examines flood events and related human interactions in the northwestern Himalayan Buri Gandaki Valley(Nepal). Past flood events that left traces at elevations between 3745 m to 780 m above sea level were investigated and reconstructed using morphometric and descriptive fluvial geomorphological analyses of historical flood markers and their related forms in the Buri Gandaki River system. Furthermore, the discharge of the Buri Gandaki River was measured, and infrastructure and permanent and temporary settlements potentially influenced by floods in the region due to their proximity to natural hazard areas were mapped. All reconstructed flood indicators have been documented with photographs that illustrate the evolution of the landscape over a short period in the Holocene. Moreover, satellite images have confirmed the morphological findings at the mesoscale and macroscale. An analysis of the flood levels showed that the high-water marks between 2160 m and 1710 m above sea level represented the highest reconstructed paleoflood stages. An intense flood hazard was observed in the upper stream of the Buri Gandaki near the Birendra Kund glacial lake and Samagaun settlement(3520 m above sea level). Further conclusions may be drawn from the anthropogenic reactions to flooding, such as those of the ethnic groups in this valley, who have used their local knowledge of floods and high discharge events along the Buri Gandaki River to takesafety precautions. Thus, local knowledge has reduced the social vulnerability in the settled areas of the valley. As a result of these local adaption strategies within the valley, we must rethink our implementation of protection and urbanisation strategies.展开更多
基金The National Natural Science Foundation of China(41761144081)The Second Tibetan Plateau Scientific Expedition and Research(2019QZKK2203)+1 种基金The International Partnership Program of Chinese Academy of Sciences(131C11KYSB20160061)The Chinese Academy of Sciences-The World Academy of Sciences(CAS-TWAS)President’s Fellowship Program for Ph D Study
文摘Urban growth is a key indicator of economic development.At the same time,haphazard urban growth creates serious socioeconomic,environmental and urban land management problems.In this context,understanding the process of urban landscape change is important for guiding the sustainable growth of urban areas.This study analyzes the urban land changes during 1990–2018 in two metropolitan cities of Gandaki basin:Pokhara and Bharatpur.Landsat satellite images were analyzed using supervised classification methods.The results revealed that the built-up area has increased significantly by 300%in Pokhara and by nearly 500%in the Bharatpur during the past 28 years.Population growth,migration from surrounding areas due to urban facilities and the easy lifestyle in cities were found to be major determinants of urban growth within the study area.In addition,the changing urban definition and expansion of municipal boundaries are key factors for rapid urban growth.Both cities are likely to grow in the future as they are both located in areas that encompass the high levels of commercial activity and modern service facilities.The haphazard urban growth should be minimized through planning and policies for sustainable urban development.
文摘In its upper and middle course, the Kali Gandaki river in Western Nepal flows across the Himalayan ranges more or less following tectonic lineaments (NNE—SSW). In this paper we focus our attention on certain slope deformations along the valley flanks of the middle course, especially on very narrow sections of this large transverse valley. Although the valley experienced several Pleistocene periods of strong glaciations and the powerful river flowing through it currently ranks as the second largest in Nepal we find a number of those amazing valley constrictions in the studied area which should not be ascribed to differences in rock resistance against erosion or to active tectonic control. It can best be explained by deep\|seated rock creep (Chigira,1992), a process which is frequently connected with landslides or rockfalls and must have developed during late Pleistocene and Holocene, i.e. since the valley was deglaciated. In order to prove this thesis we shall describe the situation by means of three case studies between the villages of Rukse (upstream) and Beni (downstream). Another fourth example of gravitational slope deformation described in this paper is located downstream of the reach of previous valley glaciations. Here, too, deep\|seated rock creep is considered to be responsible for the observed mass movements and thus for slope deformation.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(2019QZKK0603)the Strategic Priority Research Program of Chinese Academy of Sciences(XDA20040201)the Chinese Academy of Sciences-The World Academy of Sciences(CAS-TWAS)President’s Fellowship Program for international PhD students and the Chinese Academy of Sciences President’s International Fellowship Initiative for postdoctoral research(2018PC0030)。
文摘The Gandaki River Basin(GRB),located in the central Himalaya,provides habitats for a large number of important flora and fauna species.The habitats of key protected species have changed over time as a result of climate changes and human activities related to land use change,including the development of roads.This study assessed the present and future distributions of sloth bear(Melursus ursinus)habitats using the maximum entropy(Max Ent)model.Bioclimatic data,a digital elevation model and roads were used as environmental layers to assess current and future distributions of habitat.Results show that the overall habitat within the study area is likely to undergo important changes in the future.Bio 8(the mean temperature of the wettest quarter)and slope were found to be important variables affecting the distribution of the species.The habitats very highly suitable for sloth bears currently cover an area of 148 km^(2) within the GRB.These habitats are predicted to increase by 122 km^(2) more by 2050.Overall,a net change by 680.38 km^(2) was found in the GRB.Conservation measures are necessary for this key protected species and its habitat within the GRB and elsewhere in Nepal.
基金Chinese Academy of Sciences-The World Academy of Sciences(CAS-TWAS)President's Fellowship Program for PhD Study。
文摘Gandaki River Basin(GRB) is part of the central Himalayan region, which provides habitat for numerous wild species. However, due to changes in climate and land cover, the habitats of many protected species are at risk. Based on the maximum entropy(MaxEnt) model, coupled with bioclimatic layers, land cover and DEM data, the impacts of environmental factors on habitat suitability of Himalayan Monal(Lophophorus impejanus), a national bird of Nepal, was quantified. This study further assessed the present and future habitat and distribution of the Himalayan Monal in the context of climate and land cover changes. The results of this study show that the highly suitable habitat of Himalayan Monal presently occupies around 749 km^2 within the northern, eastern and western parts, particularly protected areas such as Langtang National Park, Manaslu Conservation Area and Annapurna Conservation Area, while it is likely to decrease to 561 km^2 by 2050, primarily in the northern and northwestern parts(i.e., Chhyo, Tatopani, Humde and Chame). These expected changes indicate increasing risk for Himalayan Monal due to a decline in its suitable habitat area.
基金The Second Tibetan Plateau Scientific Expedition and Research(2019QZKK0603)The Strategic Priority Research Program of Chinese Academy of Sciences(XDA20040201)The National Natural Science Foundation of China(41761144081)。
文摘Gandaki River Basin(GRB)is an important part of the central Himalayan region,which provides habitat for numerous wild species.However,climatic changes are making the habitat in this basin more vulnerable.This paper aims to assess the potential impacts of climate change on the spatial distributions of habitat changes for two vulnerable species,Himalayan black bear(Ursus thibetanus laniger)and common leopard(Panthera pardus fusca),using the maximum entropy(Max Ent)species distribution model.Species occurrence locations were used along with several bioclimatic and topographic variables(elevation,slope and aspect)to fit the model and predict the potential distributions(current and future)of the species.The results show that the highly suitable area of Himalayan black bear within the GRB currently encompasses around 1642 km^(2)(5.01%area of the basin),which is predicted to increase by 51 km^(2) in the future(2050).Similarly,the habitat of common leopard is estimated as 3999 km^(2)(12.19%of the GRB area),which is likely to increase to 4806 km^(2) in 2050.Spatially,the habitat of Himalayan black bear is predicted to increase in the eastern part(Baseri,Tatopani and north from Bhainse)and to decrease in the eastern(Somdang,Chhekampar),western(Burtibang and Bobang)and northern(Sangboche,Manang,Chhekampar)parts of the study area.Similarly,the habitat of common leopard is projected to decrease particularly in the eastern,western and southern parts of the basin,although it is estimated to be extended in the southeastern(Bhainse),western(Harichaur and northern Sandhikhark)and north-western(Sangboche)parts of the basin.To determine the habitat impact,the environmental variables such as elevation,Bio 15(precipitation seasonality)and Bio 16(precipitation of wettest quarter)highly contribute to habitat change of Himalayan black bear;while Bio 13(precipitation of wettest month)and Bio 15 are the main contributors for common leopard.Overall,this study predicted that the suitable habitat areas of both species are likely to be impacte
基金Funding for this field investigation was provided by the Otto VahlbruchStiftung (Gottingen)
文摘This research examines flood events and related human interactions in the northwestern Himalayan Buri Gandaki Valley(Nepal). Past flood events that left traces at elevations between 3745 m to 780 m above sea level were investigated and reconstructed using morphometric and descriptive fluvial geomorphological analyses of historical flood markers and their related forms in the Buri Gandaki River system. Furthermore, the discharge of the Buri Gandaki River was measured, and infrastructure and permanent and temporary settlements potentially influenced by floods in the region due to their proximity to natural hazard areas were mapped. All reconstructed flood indicators have been documented with photographs that illustrate the evolution of the landscape over a short period in the Holocene. Moreover, satellite images have confirmed the morphological findings at the mesoscale and macroscale. An analysis of the flood levels showed that the high-water marks between 2160 m and 1710 m above sea level represented the highest reconstructed paleoflood stages. An intense flood hazard was observed in the upper stream of the Buri Gandaki near the Birendra Kund glacial lake and Samagaun settlement(3520 m above sea level). Further conclusions may be drawn from the anthropogenic reactions to flooding, such as those of the ethnic groups in this valley, who have used their local knowledge of floods and high discharge events along the Buri Gandaki River to takesafety precautions. Thus, local knowledge has reduced the social vulnerability in the settled areas of the valley. As a result of these local adaption strategies within the valley, we must rethink our implementation of protection and urbanisation strategies.
