This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrologic...This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrological simulation and analyzing the factors affecting runoff volume.Runoff volume and runoff depth were simulated using the VIC model and its performance was evaluated.Meanwhile,the factors affecting runoff volume were analyzed using Spearman correlation.The following model sensitivity parameters were obtained based on the China Natural Runoff Grid Point Dataset(CNRD v1.0):The variable infiltration curve parameter was 0.3,the Dsmax fraction where non-linear baseflow begins was 0.02,the maximum baseflow velocity was 15 mm/d,the maximum soil moisture where non-linear baseflow occurred was 0.7,the second soil moisture layer thickness was 0.3,and the thickness of the third soil moisture layer was 1.5.The surface runoff values in the Nyang River basin were similar in the first and fourth quarters(1.05–2.27 mm and 2.38–4.77 mm,respectively),and the surface runoff values were similar in the second and third quarters when the surface runoff was greater(23.46–52.20 mm and 60.59–85.63 mm,respectively).Watershed area,temperature,and precipitation significantly influenced the amount of runoff from the Nyang River.The applicability of the model to the Nyang River basin was confirmed using two different rate models.In some areas,precipitation and temperature did not have a dominating influence on runoff.Although the VIC model has significant advantages in runoff simulation,it requires a wealth of meteorological,soil,and hydrological data that may be difficult to obtain in some areas.展开更多
Nyang-nyi-ma-vor-zer is a famous historical fi gure of the Nyingma in twelfth Century. He learned various dharma based on Esoteric Buddhism, and achieved a high level of achievement. He Made an important contribution ...Nyang-nyi-ma-vor-zer is a famous historical fi gure of the Nyingma in twelfth Century. He learned various dharma based on Esoteric Buddhism, and achieved a high level of achievement. He Made an important contribution to esoteric buddhism. Although Tibetan Buddhism history recorded Nyangs stories, at present, there is not enough attention on the research of Nyangs. In this paper, we mainly discussed Nyangs life story and his historical records <Nyangs Dharma Resources>.展开更多
There are a large number of glaciers and lakes developed in the Nyang Qu Basin of China. Recent climate change has significant impacted on the high-mountain glacial environment. Rapid melting of glaciers contributes t...There are a large number of glaciers and lakes developed in the Nyang Qu Basin of China. Recent climate change has significant impacted on the high-mountain glacial environment. Rapid melting of glaciers contributes to the formation and expansion of moraine-dammed lakes which increase the probability of glacial lake outburst floods(GLOFs). We calculated a multi-temporal lake inventory based on(1) topographic maps in the 1970 s,(2) satellite imageries from 1990 to 2016,(3) First Chinese Glacier Inventory(FCGI),(4) Glacier Inventory of Southeastern Tibet(GIST) and(5) meteorological data. A total of 880 lakes(>0.01 km^2) have been mapped in 2016, with 318 being glacial lakes(GLs) and 462 non-glacier lakes(NGLs). Most of the lakes were mainly located at 4500 m a.s.l. and the lakes dominated by small lakes(<0.1 km^2) where the change of their actual sizes are more significant compared to the larger ones. Meanwhile, we found that there were 178 newly formed GLs and 51 of them had disappeared between 1970 and 2016. During the same period, there can be identified 157 newly formed GLs and 226 had disappeared. We additionally performed a hazard and risk assessment for GL in 2016 and exposed 14 potentially dangerous morainedammed lakes(PDMDLs), covering a total area of 5.88 km2 in the Nyang Qu Basin. There can be found 4 GLs with very high risk, 3 GLs with high risk, 4 GLs with medium risk and 4 GLs with low risk of GLOFs susceptibility. The findings of this study can be used for the future policy of risk management and also be adapted for promoting water resources management.展开更多
Land use/land cover(LULC)is an important part of exploring the interaction between natural environment and human activities and achieving regional sustainable development.Based on the data of LULC types(cropland,fores...Land use/land cover(LULC)is an important part of exploring the interaction between natural environment and human activities and achieving regional sustainable development.Based on the data of LULC types(cropland,forest land,grassland,built-up land,and unused land)from 1990 to 2015,we analysed the intensity and driving factors of land use/cover change(LUCC)in the Yarlung Zangbo River,Nyang Qu River,and Lhasa River(YNL)region,Qinghai-Tibet Plateau of China,using intensity analysis method,cross-linking table method,and spatial econometric model.The results showed that LUCC in the YNL region was nonstationary from 1990 to 2015,showing a change pattern with"fast-slow-fast"and"U-shaped".Built-up land showed a steady increase pattern,while cropland showed a steady decrease pattern.The gain of built-up land mainly came from the loss of cropland.The transition pattern of LUCC in the YNL region was relatively single and stable during 1990–2015.The transition pattern from cropland and forest land to built-up land was a systematic change process of tendency and the transition pattern from grassland and unused land to cropland was a systematic change process of avoidance.The transition process of LUCC was the result of the combined effect of natural environment and social economic development in the YNL region.This study reveals the impact of ecological environment problems caused by human activities on the land resource system and provides scientific support for the study of ecological environment change and sustainable development of the Qinghai-Tibet Plateau.展开更多
基金supported by the Key R&D Project of Science and Technology Program of Tibet Autonomous Region(XZ202301ZY0006G)the Graduate High-level Talent Training Program of Xizang University(2022-GSP-B007)+1 种基金Nagqu City Science and Technology Program Key R&D Projects(NQKJ-2023-15)Central Financial Support for Local Universities to Construct Wetland Station in Mitika and Collaborative Innovation Center for Ecological Civilization of the Qinghai-Tibetan Plateau([2024]NO.01).
文摘This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrological simulation and analyzing the factors affecting runoff volume.Runoff volume and runoff depth were simulated using the VIC model and its performance was evaluated.Meanwhile,the factors affecting runoff volume were analyzed using Spearman correlation.The following model sensitivity parameters were obtained based on the China Natural Runoff Grid Point Dataset(CNRD v1.0):The variable infiltration curve parameter was 0.3,the Dsmax fraction where non-linear baseflow begins was 0.02,the maximum baseflow velocity was 15 mm/d,the maximum soil moisture where non-linear baseflow occurred was 0.7,the second soil moisture layer thickness was 0.3,and the thickness of the third soil moisture layer was 1.5.The surface runoff values in the Nyang River basin were similar in the first and fourth quarters(1.05–2.27 mm and 2.38–4.77 mm,respectively),and the surface runoff values were similar in the second and third quarters when the surface runoff was greater(23.46–52.20 mm and 60.59–85.63 mm,respectively).Watershed area,temperature,and precipitation significantly influenced the amount of runoff from the Nyang River.The applicability of the model to the Nyang River basin was confirmed using two different rate models.In some areas,precipitation and temperature did not have a dominating influence on runoff.Although the VIC model has significant advantages in runoff simulation,it requires a wealth of meteorological,soil,and hydrological data that may be difficult to obtain in some areas.
文摘Nyang-nyi-ma-vor-zer is a famous historical fi gure of the Nyingma in twelfth Century. He learned various dharma based on Esoteric Buddhism, and achieved a high level of achievement. He Made an important contribution to esoteric buddhism. Although Tibetan Buddhism history recorded Nyangs stories, at present, there is not enough attention on the research of Nyangs. In this paper, we mainly discussed Nyangs life story and his historical records <Nyangs Dharma Resources>.
基金the National Natural Science Foundation of China(No.41761144075,No.41861013)Yunnan University(YJRC3201702)National Natural Science Foundation of China Youth Fund Project(No.41801052)。
文摘There are a large number of glaciers and lakes developed in the Nyang Qu Basin of China. Recent climate change has significant impacted on the high-mountain glacial environment. Rapid melting of glaciers contributes to the formation and expansion of moraine-dammed lakes which increase the probability of glacial lake outburst floods(GLOFs). We calculated a multi-temporal lake inventory based on(1) topographic maps in the 1970 s,(2) satellite imageries from 1990 to 2016,(3) First Chinese Glacier Inventory(FCGI),(4) Glacier Inventory of Southeastern Tibet(GIST) and(5) meteorological data. A total of 880 lakes(>0.01 km^2) have been mapped in 2016, with 318 being glacial lakes(GLs) and 462 non-glacier lakes(NGLs). Most of the lakes were mainly located at 4500 m a.s.l. and the lakes dominated by small lakes(<0.1 km^2) where the change of their actual sizes are more significant compared to the larger ones. Meanwhile, we found that there were 178 newly formed GLs and 51 of them had disappeared between 1970 and 2016. During the same period, there can be identified 157 newly formed GLs and 226 had disappeared. We additionally performed a hazard and risk assessment for GL in 2016 and exposed 14 potentially dangerous morainedammed lakes(PDMDLs), covering a total area of 5.88 km2 in the Nyang Qu Basin. There can be found 4 GLs with very high risk, 3 GLs with high risk, 4 GLs with medium risk and 4 GLs with low risk of GLOFs susceptibility. The findings of this study can be used for the future policy of risk management and also be adapted for promoting water resources management.
基金jointly supported by the Second Tibetan Plateau Scientific Expedition and Research of China(2019QZKK0603)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20040200)Reconstruction of Historical Cultivated Land and Human Activities around the North Slope of Everest Area of China(42061023)。
文摘Land use/land cover(LULC)is an important part of exploring the interaction between natural environment and human activities and achieving regional sustainable development.Based on the data of LULC types(cropland,forest land,grassland,built-up land,and unused land)from 1990 to 2015,we analysed the intensity and driving factors of land use/cover change(LUCC)in the Yarlung Zangbo River,Nyang Qu River,and Lhasa River(YNL)region,Qinghai-Tibet Plateau of China,using intensity analysis method,cross-linking table method,and spatial econometric model.The results showed that LUCC in the YNL region was nonstationary from 1990 to 2015,showing a change pattern with"fast-slow-fast"and"U-shaped".Built-up land showed a steady increase pattern,while cropland showed a steady decrease pattern.The gain of built-up land mainly came from the loss of cropland.The transition pattern of LUCC in the YNL region was relatively single and stable during 1990–2015.The transition pattern from cropland and forest land to built-up land was a systematic change process of tendency and the transition pattern from grassland and unused land to cropland was a systematic change process of avoidance.The transition process of LUCC was the result of the combined effect of natural environment and social economic development in the YNL region.This study reveals the impact of ecological environment problems caused by human activities on the land resource system and provides scientific support for the study of ecological environment change and sustainable development of the Qinghai-Tibet Plateau.
