The paper focuses on geological and geochemical evidence of thermal brine genesis of Pb Zn deposits in Wuqia district, Xinjiang. The results suggest that the known Pb Zn deposits, such as Wulagen, are thermal brine ge...The paper focuses on geological and geochemical evidence of thermal brine genesis of Pb Zn deposits in Wuqia district, Xinjiang. The results suggest that the known Pb Zn deposits, such as Wulagen, are thermal brine genesis, which is supported by the features of tectonic setting, magma and regional metamorphism, and the characteristics of trace element distribution in strata and redistribution in the ore forming process, the REE patterns and their main parameters of main type ores, the composition features and the source indicators of Pb, S isotopes. Ore forming conditions of superlarge Pb Zn deposits studies show that there exists tectonic and sources setting of Jinding type superlarge Pb Zn deposits in this area. Five Pb Zn ore belts and central uplift belts discovered lately have not only confirmed that the genesis of Wulagen Pb Zn deposits is thermal genesis, but also further proved that there exists tectonic and source setting of Jinding type superlarge Pb Zn deposit in the study area. Mineral deposit model was described and prospecting potentiality of superlarge Pb Zn deposit and their significance were discussed.展开更多
Air temperature and snow cover variability are sensitive indicators of climate change. This study was undertaken to forecast and quantify the potential streamflow response to climate change in the Jhelum River basin. ...Air temperature and snow cover variability are sensitive indicators of climate change. This study was undertaken to forecast and quantify the potential streamflow response to climate change in the Jhelum River basin. The implications of air temperature trends （＋0.11℃decade） reported for the entire north-west Himalaya for past century and the regional warming （＋0.7℃/decade） trends of three observatories analyzed between last two decades were used for future projection of snow cover depletion and stream flow. The streamflow was simulated and validated for the year 2007-2008 using snowmelt runoff model （SRM） based on in-situ temperature and precipitation with remotely sensed snow cover area. The simulation was repeated using higher values of temperature and modified snow cover depletion curves according to the assumed future climate. Early snow cover depletion was observed in the basin in response to warmer climate. The results show that with the increase in air temperature, streamfiow pattern of Jhelum will be severely affected. Significant redistribution of streamflow was observed in both the scenarios. Higher discharge was observed during spring-summer months due to early snowmelt contribution with water deficit during monsoon months. Discharge increased by 5%-40% during the months of March to May in 2030 and 2050. The magnitude of impact of air temperature is higher in the scenario-2 based on regional warming. The inferences pertaining to change in future streamflow pattern can facilitate long term decisions and planning concerning hydro-power potential, waterresource management and flood hazard mapping in the region.展开更多
Recent changes occurred in terminus of the debris-covered Bilafond Glacier in the Karakoram Range in the Himalayas, Northern Pakistan was investigated in this research. Landsat MSS, TM and ETM+ images were used for th...Recent changes occurred in terminus of the debris-covered Bilafond Glacier in the Karakoram Range in the Himalayas, Northern Pakistan was investigated in this research. Landsat MSS, TM and ETM+ images were used for this study. Digital elevation models derived from ASTER GDEM and SRTM were also utilized. Visible, infrared and thermal infrared channels were utilized in order to get accurate glacier change maps. Three methods were tried to map this debris-covered glacier in this research. The glacier has been mapped successfully and the changes in the glacier terminus from 1978 to 2011 have been calculated. Manual, semi-automatic and thermal methods were found to give similar results. It was found that the glacier has undergone serious ablation during this period despite of the fact that many of the larger glaciers in the Hindu Kush and Karakoram mountain regions in the Upper Indus Basin were reported to be expanding. The terminus has been moved back about 600 meters during this period and there was an abrupt change in the glacier terminus during 1990-2002. We propose that debris thickness is not the only factor that influences the glacier ablation but the altitude of the debris-covered glacier as well. Many glaciers in the Karakoram region reported to be expanding were having higher altitudes compared to the study area.展开更多
Ten quantitative morphological characters were studied in 56 Morus alba L. trees representing three natural populations from the trans-Himalayan Ladakh region. The altitude of collection sites ranged from 2815 to 3177...Ten quantitative morphological characters were studied in 56 Morus alba L. trees representing three natural populations from the trans-Himalayan Ladakh region. The altitude of collection sites ranged from 2815 to 3177 m above the sea level(asl). Coefficient of variation(CV) showed high phenotypic variation in M. alba. Linear regression analysis revealed that leaf and fruit size decreases with an increase in altitude. High CV was observed for leaf length, leaf width, petiole length, leaf area, internodal distance, number of nodes, bud length, fruit length, fruit width and fruit weight. Similarly, a high phenotypic plasticity index was observed for bud length, leaf length, leaf width, petiole length, leaf area, inter-nodal distance, number of nodes, fruit length, fruit width and fruit weight. For every 100 m increase in altitude, leaf length, leaf width and leaf area decreased by 1 cm, 0.8 cm and 16.6 cm2, respectively. Analysis of covariance showed a predominant altitudinal effect on the morphological characters in comparison to the population effect. A small change in the altitude caused significant change in the plant morphological characteristics. The present investigation represents to our knowledge the first study addressing phenotypic variation in mulberryalong an altitudinal gradient.展开更多
The Mw 7.8 Gorkha earthquake in Nepal on April 25, 2015, produced thousands of landslides in the Himalayan mountain range. After the earthquake, two field investigations along Araniko Highway were conducted. Then, usi...The Mw 7.8 Gorkha earthquake in Nepal on April 25, 2015, produced thousands of landslides in the Himalayan mountain range. After the earthquake, two field investigations along Araniko Highway were conducted. Then, using remote sensing technology and geographic information system(GIS)technology, 1481 landslides were identified along the Bhote Koshi river. Correlations between the spatial distribution of landslides with slope gradient and lithology were analyzed. The power-law relationship of the size distribution of earthquake-induced landslides was examined in both the Higher Himalaya and Lesser Himalaya. Possible reasons for the variability of the power exponent were explored by examining differences in the geological situations of these areas. Multi-threshold cellular automata were introduced to model the complexity of system components. Most of the landslides occurred at slope gradients of 30°–40°, and the landslide density was positively correlated with slope gradient. Landslides in hard rock areas were more common than in soft rock areas. The cumulative number-area distribution of landslides induced by the Gorkha earthquake exhibited a negative power-law relationship, but the power exponents were different: 1.13 in the Higher Himalaya, 1.36 and Lesser Himalaya. Furthermore,the geological conditions were more complex and varied in the Lesser Himalaya than in the Higher Himalaya, and the cellular automata simulation results indicated that, as the complexity of system components increased, the power exponent increased.Therefore, the variability of the power exponent of landslide size distribution should ascribe to the complexity of geological situations in the Bhote Koshi river watershed.展开更多
Land use changes such as deforestation,increase in cropping or grazing areas and built-up land, likely modify the water balance and land surface behavior in the Himalayan watersheds.An integrated approach of hydrologi...Land use changes such as deforestation,increase in cropping or grazing areas and built-up land, likely modify the water balance and land surface behavior in the Himalayan watersheds.An integrated approach of hydrological and hydraulic modeling was adopted for comparative analysis of hydrological pattern in three Himalayan watersheds i.e.Khanpur,Rawal and Simly situated in the Northern territory of Pakistan.The rainfall-runoff model SWAT- Soil and water assessment tool and Hydro CAD were calibrated for the selected watersheds.The correlation analysis of the precipitation data of two climate stations i.e.Murree and Islamabad, with the discharge data of three rivers was utilized to select best suitable input precipitation data for Hydro CAD rainfall-runoff modeling.The peak flood hydrograph were generated using Hydro CAD runoff to optimize the basin parameters like CN, runoff volume, peak flows of the three watersheds.The hydrological response of the Rawal watershed was studied as a case study to different scenarios of land use change using SWAT model.The scenario of high deforestation indicated a decline of about 6.3% in the groundwater recharge tostream while increase of 7.1% in the surface runoff has been observed under the scenario of growth in urbanization in the recent decades.The integrated modeling approach proved helpful in investigating the hydrological behavior under changing environment at watershed level in the Himalayan region.展开更多
With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantita...With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantitative analysis of the snow cover in the higher Himalayas. In this study, a nonlinear autoregressive exogenous model, an artificial neural network （ANN）, was deployed to predict the snow cover in the Kaligandaki river basin for the next 30 years. Observed climatic data, and snow covered area was used to train and test the model that captures the gross features of snow under the current climate scenario. The range of the likely effects of climate change on seasonal snow was assessed in the Himalayas using downscaled temperature and precipitation change projection from - HadCM3, a global circulation model to project future climate scenario, under the AIB emission scenario, which describes a future world of very rapid economic growth with balance use between fossil and non-fossil energy sources. The results show that there is a reduction of 9% to 46% of snow cover in different elevation zones during the considered time period, i.e., 2Oll to 2040. The 4700 m to 52oo m elevation zone is the most affected area and the area higher than 5200 m is the least affected. Overall, however, it is clear from the analysis that seasonal snow in the Kaligandaki basin is likely to be subject to substantialchanges due to the impact of climate change.展开更多
This paper studies electrical resistivity dataset acquired for a groundwater study in the Domail Plain in the northwestern Himalayan section of Pakistan. Through a combination of geostatistical analysis,geophysical in...This paper studies electrical resistivity dataset acquired for a groundwater study in the Domail Plain in the northwestern Himalayan section of Pakistan. Through a combination of geostatistical analysis,geophysical inversion and visualization techniques,it is possible to re-model and visualize the single dimension resistivity data into 2D and 3D space.The variogram models are utilized to extend the interpretation of the data and to distinguish individual lithologic units and the occurrence of saline water within the subsurface. The resistivity data has been calibrated with the lithological logs taken from the available boreholes. As such the alluvial system of the Domail Plain has formed during episodes of local tectonic activity with fluvial erosion and depositionyielding coarse sediments with high electrical resistivities near to the mountain ranges and finer sediments with medium to low electrical resistivities which tend to settle in the basin center. Thus a change is depositional setting happened from basin lacustrine environment to flash flooding during the Himalayan orogeny. The occurrence of rock salt in the northern mountains has imparted a great influence on the groundwater quality of the study area. The salt is dissolved by water which infiltrates into the subsurface through the water channels. Variogram aided gridding of resistivity data helps to identify the occurrence and distribution of saline water in the subsurface.展开更多
Indigenous agroforestry systems have been practiced for centuries in the Himalaya Mountains and adjoining regions.With the increase of climate change associated risks,enhanced understanding of the impact of climate ch...Indigenous agroforestry systems have been practiced for centuries in the Himalaya Mountains and adjoining regions.With the increase of climate change associated risks,enhanced understanding of the impact of climate change and related phenomena on the potential distribution of agroforestry is increasingly useful and necessary,for both maintaining and improving yield and ecosystem function.In particular,展开更多
The Chinese yew（Taxus wallichiana）,which is widely distributed in the Himalayas and in southern China,is now on the edge of extinction.In order to understand the evolutionary processes that control the current diver...The Chinese yew（Taxus wallichiana）,which is widely distributed in the Himalayas and in southern China,is now on the edge of extinction.In order to understand the evolutionary processes that control the current diversity within this species at the genetic and ecological levels,its genetic patterns and range dynamics must first be identified and mapped.This knowledge can then be applied in the development of an effective conservation strategy.Based on molecular data obtained from 48 populations of T.wallichiana,we used GIS-based interpolation approach for the explicit visualization of patterns of genetic divergence and diversity,and a number of potential evolutionary hotspots have been specifically identified within the genetic landscape maps.Within the maps of genetic divergence and diversity,five areas of high inter-population genetic divergence and six areas of high intra-population genetic diversity have been highlighted in a number of separate mountain regions,and these evolutionary hotspots should have the priority to be protected.Furthermore,four geographical barriers have been identified： the eastern Himalayas,the Yunnan Plateau,the Hengduan Mountains and the Taiwan Strait.According to ecological niche modeling（ENM）,the populations of T.wallichiana within the Sino-Himalayan Forest floristic subkingdom experienced westward expansion from the periods of Last Inter-glacial to Last Glacial Maximum（LGM）.Following the LGM,the distribution range overall became reduced and fragmented.These findings challenge the classic mode of contraction-expansion in response to the last glaciation.In conclusion,our findings suggest that the changes in geographical landscapes and climate that occurred during the Quaternary resulted in current genetic landscape patterns.展开更多
基金TheNationalNaturalScienceFoundationofChina (No .4 0 0 72 0 32 )
文摘The paper focuses on geological and geochemical evidence of thermal brine genesis of Pb Zn deposits in Wuqia district, Xinjiang. The results suggest that the known Pb Zn deposits, such as Wulagen, are thermal brine genesis, which is supported by the features of tectonic setting, magma and regional metamorphism, and the characteristics of trace element distribution in strata and redistribution in the ore forming process, the REE patterns and their main parameters of main type ores, the composition features and the source indicators of Pb, S isotopes. Ore forming conditions of superlarge Pb Zn deposits studies show that there exists tectonic and sources setting of Jinding type superlarge Pb Zn deposits in this area. Five Pb Zn ore belts and central uplift belts discovered lately have not only confirmed that the genesis of Wulagen Pb Zn deposits is thermal genesis, but also further proved that there exists tectonic and source setting of Jinding type superlarge Pb Zn deposit in the study area. Mineral deposit model was described and prospecting potentiality of superlarge Pb Zn deposit and their significance were discussed.
文摘Air temperature and snow cover variability are sensitive indicators of climate change. This study was undertaken to forecast and quantify the potential streamflow response to climate change in the Jhelum River basin. The implications of air temperature trends （＋0.11℃decade） reported for the entire north-west Himalaya for past century and the regional warming （＋0.7℃/decade） trends of three observatories analyzed between last two decades were used for future projection of snow cover depletion and stream flow. The streamflow was simulated and validated for the year 2007-2008 using snowmelt runoff model （SRM） based on in-situ temperature and precipitation with remotely sensed snow cover area. The simulation was repeated using higher values of temperature and modified snow cover depletion curves according to the assumed future climate. Early snow cover depletion was observed in the basin in response to warmer climate. The results show that with the increase in air temperature, streamfiow pattern of Jhelum will be severely affected. Significant redistribution of streamflow was observed in both the scenarios. Higher discharge was observed during spring-summer months due to early snowmelt contribution with water deficit during monsoon months. Discharge increased by 5%-40% during the months of March to May in 2030 and 2050. The magnitude of impact of air temperature is higher in the scenario-2 based on regional warming. The inferences pertaining to change in future streamflow pattern can facilitate long term decisions and planning concerning hydro-power potential, waterresource management and flood hazard mapping in the region.
基金Rio Grande do Sul State Foundation for Research (FAPERGS), Brazil for financial support
文摘Recent changes occurred in terminus of the debris-covered Bilafond Glacier in the Karakoram Range in the Himalayas, Northern Pakistan was investigated in this research. Landsat MSS, TM and ETM+ images were used for this study. Digital elevation models derived from ASTER GDEM and SRTM were also utilized. Visible, infrared and thermal infrared channels were utilized in order to get accurate glacier change maps. Three methods were tried to map this debris-covered glacier in this research. The glacier has been mapped successfully and the changes in the glacier terminus from 1978 to 2011 have been calculated. Manual, semi-automatic and thermal methods were found to give similar results. It was found that the glacier has undergone serious ablation during this period despite of the fact that many of the larger glaciers in the Hindu Kush and Karakoram mountain regions in the Upper Indus Basin were reported to be expanding. The terminus has been moved back about 600 meters during this period and there was an abrupt change in the glacier terminus during 1990-2002. We propose that debris thickness is not the only factor that influences the glacier ablation but the altitude of the debris-covered glacier as well. Many glaciers in the Karakoram region reported to be expanding were having higher altitudes compared to the study area.
基金supported by Defence Research and Development Organization (DRDO),Ministry of Defence, Government of India
文摘Ten quantitative morphological characters were studied in 56 Morus alba L. trees representing three natural populations from the trans-Himalayan Ladakh region. The altitude of collection sites ranged from 2815 to 3177 m above the sea level(asl). Coefficient of variation(CV) showed high phenotypic variation in M. alba. Linear regression analysis revealed that leaf and fruit size decreases with an increase in altitude. High CV was observed for leaf length, leaf width, petiole length, leaf area, internodal distance, number of nodes, bud length, fruit length, fruit width and fruit weight. Similarly, a high phenotypic plasticity index was observed for bud length, leaf length, leaf width, petiole length, leaf area, inter-nodal distance, number of nodes, fruit length, fruit width and fruit weight. For every 100 m increase in altitude, leaf length, leaf width and leaf area decreased by 1 cm, 0.8 cm and 16.6 cm2, respectively. Analysis of covariance showed a predominant altitudinal effect on the morphological characters in comparison to the population effect. A small change in the altitude caused significant change in the plant morphological characteristics. The present investigation represents to our knowledge the first study addressing phenotypic variation in mulberryalong an altitudinal gradient.
基金supported by the National Natural Science Foundation of China (Grant No. 41571004)National Program on Key Research Project of China (Grant No. 2016YFC0802206)+1 种基金Key Laboratory Foundation of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences (Grant No. KLMHESP-17-03)the Fundamental Research Funds for the Central Universities of China (Grant No. 2682016CX003)
文摘The Mw 7.8 Gorkha earthquake in Nepal on April 25, 2015, produced thousands of landslides in the Himalayan mountain range. After the earthquake, two field investigations along Araniko Highway were conducted. Then, using remote sensing technology and geographic information system(GIS)technology, 1481 landslides were identified along the Bhote Koshi river. Correlations between the spatial distribution of landslides with slope gradient and lithology were analyzed. The power-law relationship of the size distribution of earthquake-induced landslides was examined in both the Higher Himalaya and Lesser Himalaya. Possible reasons for the variability of the power exponent were explored by examining differences in the geological situations of these areas. Multi-threshold cellular automata were introduced to model the complexity of system components. Most of the landslides occurred at slope gradients of 30°–40°, and the landslide density was positively correlated with slope gradient. Landslides in hard rock areas were more common than in soft rock areas. The cumulative number-area distribution of landslides induced by the Gorkha earthquake exhibited a negative power-law relationship, but the power exponents were different: 1.13 in the Higher Himalaya, 1.36 and Lesser Himalaya. Furthermore,the geological conditions were more complex and varied in the Lesser Himalaya than in the Higher Himalaya, and the cellular automata simulation results indicated that, as the complexity of system components increased, the power exponent increased.Therefore, the variability of the power exponent of landslide size distribution should ascribe to the complexity of geological situations in the Bhote Koshi river watershed.
文摘Land use changes such as deforestation,increase in cropping or grazing areas and built-up land, likely modify the water balance and land surface behavior in the Himalayan watersheds.An integrated approach of hydrological and hydraulic modeling was adopted for comparative analysis of hydrological pattern in three Himalayan watersheds i.e.Khanpur,Rawal and Simly situated in the Northern territory of Pakistan.The rainfall-runoff model SWAT- Soil and water assessment tool and Hydro CAD were calibrated for the selected watersheds.The correlation analysis of the precipitation data of two climate stations i.e.Murree and Islamabad, with the discharge data of three rivers was utilized to select best suitable input precipitation data for Hydro CAD rainfall-runoff modeling.The peak flood hydrograph were generated using Hydro CAD runoff to optimize the basin parameters like CN, runoff volume, peak flows of the three watersheds.The hydrological response of the Rawal watershed was studied as a case study to different scenarios of land use change using SWAT model.The scenario of high deforestation indicated a decline of about 6.3% in the groundwater recharge tostream while increase of 7.1% in the surface runoff has been observed under the scenario of growth in urbanization in the recent decades.The integrated modeling approach proved helpful in investigating the hydrological behavior under changing environment at watershed level in the Himalayan region.
文摘With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantitative analysis of the snow cover in the higher Himalayas. In this study, a nonlinear autoregressive exogenous model, an artificial neural network （ANN）, was deployed to predict the snow cover in the Kaligandaki river basin for the next 30 years. Observed climatic data, and snow covered area was used to train and test the model that captures the gross features of snow under the current climate scenario. The range of the likely effects of climate change on seasonal snow was assessed in the Himalayas using downscaled temperature and precipitation change projection from - HadCM3, a global circulation model to project future climate scenario, under the AIB emission scenario, which describes a future world of very rapid economic growth with balance use between fossil and non-fossil energy sources. The results show that there is a reduction of 9% to 46% of snow cover in different elevation zones during the considered time period, i.e., 2Oll to 2040. The 4700 m to 52oo m elevation zone is the most affected area and the area higher than 5200 m is the least affected. Overall, however, it is clear from the analysis that seasonal snow in the Kaligandaki basin is likely to be subject to substantialchanges due to the impact of climate change.
基金Water and Power Development Authority(WAPDA)is hereby acknowledged for their support in th e present study.
文摘This paper studies electrical resistivity dataset acquired for a groundwater study in the Domail Plain in the northwestern Himalayan section of Pakistan. Through a combination of geostatistical analysis,geophysical inversion and visualization techniques,it is possible to re-model and visualize the single dimension resistivity data into 2D and 3D space.The variogram models are utilized to extend the interpretation of the data and to distinguish individual lithologic units and the occurrence of saline water within the subsurface. The resistivity data has been calibrated with the lithological logs taken from the available boreholes. As such the alluvial system of the Domail Plain has formed during episodes of local tectonic activity with fluvial erosion and depositionyielding coarse sediments with high electrical resistivities near to the mountain ranges and finer sediments with medium to low electrical resistivities which tend to settle in the basin center. Thus a change is depositional setting happened from basin lacustrine environment to flash flooding during the Himalayan orogeny. The occurrence of rock salt in the northern mountains has imparted a great influence on the groundwater quality of the study area. The salt is dissolved by water which infiltrates into the subsurface through the water channels. Variogram aided gridding of resistivity data helps to identify the occurrence and distribution of saline water in the subsurface.
文摘Indigenous agroforestry systems have been practiced for centuries in the Himalaya Mountains and adjoining regions.With the increase of climate change associated risks,enhanced understanding of the impact of climate change and related phenomena on the potential distribution of agroforestry is increasingly useful and necessary,for both maintaining and improving yield and ecosystem function.In particular,
基金National Basic Research Program of China(No.2010CB951704)National Natural Science Foundation of China(No.41271068)
文摘The Chinese yew（Taxus wallichiana）,which is widely distributed in the Himalayas and in southern China,is now on the edge of extinction.In order to understand the evolutionary processes that control the current diversity within this species at the genetic and ecological levels,its genetic patterns and range dynamics must first be identified and mapped.This knowledge can then be applied in the development of an effective conservation strategy.Based on molecular data obtained from 48 populations of T.wallichiana,we used GIS-based interpolation approach for the explicit visualization of patterns of genetic divergence and diversity,and a number of potential evolutionary hotspots have been specifically identified within the genetic landscape maps.Within the maps of genetic divergence and diversity,five areas of high inter-population genetic divergence and six areas of high intra-population genetic diversity have been highlighted in a number of separate mountain regions,and these evolutionary hotspots should have the priority to be protected.Furthermore,four geographical barriers have been identified： the eastern Himalayas,the Yunnan Plateau,the Hengduan Mountains and the Taiwan Strait.According to ecological niche modeling（ENM）,the populations of T.wallichiana within the Sino-Himalayan Forest floristic subkingdom experienced westward expansion from the periods of Last Inter-glacial to Last Glacial Maximum（LGM）.Following the LGM,the distribution range overall became reduced and fragmented.These findings challenge the classic mode of contraction-expansion in response to the last glaciation.In conclusion,our findings suggest that the changes in geographical landscapes and climate that occurred during the Quaternary resulted in current genetic landscape patterns.
