Grassland is a key component of the ecosystem in the Qinghai Lake Basin,China.Understanding the effects of climate change and human activities on grassland productivity significantly improves ecological conservation a...Grassland is a key component of the ecosystem in the Qinghai Lake Basin,China.Understanding the effects of climate change and human activities on grassland productivity significantly improves ecological conservation and promotes sustainable vegetation growth in this area.Based on the net primary productivity(NPP)products of MOD17A3HGF(a moderate-resolution imaging spectroradiometer(MODIS)product that provides annual NPP at 500 m resolution)and meteorological data,we analyzed the spatial and temporal evolution of grassland NPP and its interaction with climate factors in the Qinghai Lake Basin from 2001 to 2022 via partial correlation and trend analysis methods.We also used the deflecting trend residual method and scenario analysis method to quantitatively assess the relative contributions of climatic factors and human activities to grassland NPP.The results revealed that:(1)during the past 22 a,grassland NPP increased considerably,with a gradient change from the northwest to the southeast of the study area;(2)sunshine duration,precipitation,and temperature positively influenced grassland NPP,with sunshine duration exerting a stronger effect on grassland NPP than precipitation and temperature;and(3)98.47%of the grassland in the study area was restored,with an average contribution of 65.00%from human activities and 35.00%from climatic alterations.Compared with climate change,human-induced factors had a greater effect on grassland NPP in this area.The results of the study not only provide important scientific support for ecological restoration and sustainable development of the basin but also offer new ideas for research on similar ecologically fragile areas.展开更多
Qinghai Lake is the largest saline lake in China.The change in the lake volume is an indicator of the variation in water resources and their response to climate change on the Qinghai-Tibetan Plateau(QTP)in China.The p...Qinghai Lake is the largest saline lake in China.The change in the lake volume is an indicator of the variation in water resources and their response to climate change on the Qinghai-Tibetan Plateau(QTP)in China.The present study quantitatively evaluated the effects of climate change and land use/cover change(LUCC)on the lake volume of the Qinghai Lake in China from 1958 to 2018,which is crucial for water resources management in the Qinghai Lake Basin.To explore the effects of climate change and LUCC on the Qinghai Lake volume,we analyzed the lake level observation data and multi-period land use/land cover(LULC)data by using an improved lake volume estimation method and Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.Our results showed that the lake level decreased at the rate of 0.08 m/a from 1958 to 2004 and increased at the rate of 0.16 m/a from 2004 to 2018.The lake volume decreased by 105.40×10^(8)m^(3)from 1958 to 2004,with the rate of 2.24×10^(8)m^(3)/a,whereas it increased by 74.02×10^(8)m^(3)from 2004 to 2018,with the rate of 4.66×10^(8)m^(3)/a.Further,the climate of the Qinghai Lake Basin changed from warm-dry to warm-humid.From 1958 to 2018,the increase in precipitation and the decrease in evaporation controlled the change of the lake volume,which were the main climatic factors affecting the lake volume change.From 1977 to 2018,the measured water yield showed an"increase-decrease-increase"fluctuation in the Qinghai Lake Basin.The effects of climate change and LUCC on the measured water yield were obviously different.From 1977 to 2018,the contribution rate of LUCC was-0.76%and that of climate change was 100.76%;the corresponding rates were 8.57%and 91.43%from 1977 to 2004,respectively,and-4.25%and 104.25%from 2004 to 2018,respectively.Quantitative analysis of the effects and contribution rates of climate change and LUCC on the Qinghai Lake volume revealed the scientific significance of climate change and LUCC,as well as their individual and combined effects in the Qinghai Lake Basin and on the QTP.This study can contribute to the water resources management and regional sustainable development of the Qinghai Lake Basin.展开更多
基金financially supported by the Lanzhou Youth Science and Technology Talent Innovation Project(2023-QN-2)the Gansu Haizhi Plan Project(GSHZJH 12-2025-04)+1 种基金the National Key Research and Development Program of China(2019YFC0507404)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20100101)。
文摘Grassland is a key component of the ecosystem in the Qinghai Lake Basin,China.Understanding the effects of climate change and human activities on grassland productivity significantly improves ecological conservation and promotes sustainable vegetation growth in this area.Based on the net primary productivity(NPP)products of MOD17A3HGF(a moderate-resolution imaging spectroradiometer(MODIS)product that provides annual NPP at 500 m resolution)and meteorological data,we analyzed the spatial and temporal evolution of grassland NPP and its interaction with climate factors in the Qinghai Lake Basin from 2001 to 2022 via partial correlation and trend analysis methods.We also used the deflecting trend residual method and scenario analysis method to quantitatively assess the relative contributions of climatic factors and human activities to grassland NPP.The results revealed that:(1)during the past 22 a,grassland NPP increased considerably,with a gradient change from the northwest to the southeast of the study area;(2)sunshine duration,precipitation,and temperature positively influenced grassland NPP,with sunshine duration exerting a stronger effect on grassland NPP than precipitation and temperature;and(3)98.47%of the grassland in the study area was restored,with an average contribution of 65.00%from human activities and 35.00%from climatic alterations.Compared with climate change,human-induced factors had a greater effect on grassland NPP in this area.The results of the study not only provide important scientific support for ecological restoration and sustainable development of the basin but also offer new ideas for research on similar ecologically fragile areas.
基金funded by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20100101)the National Key Research and Development Program of China(2019YFC0507404)the Gansu Province Science Foundation for Youth,China(20JR5RA543).
文摘Qinghai Lake is the largest saline lake in China.The change in the lake volume is an indicator of the variation in water resources and their response to climate change on the Qinghai-Tibetan Plateau(QTP)in China.The present study quantitatively evaluated the effects of climate change and land use/cover change(LUCC)on the lake volume of the Qinghai Lake in China from 1958 to 2018,which is crucial for water resources management in the Qinghai Lake Basin.To explore the effects of climate change and LUCC on the Qinghai Lake volume,we analyzed the lake level observation data and multi-period land use/land cover(LULC)data by using an improved lake volume estimation method and Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.Our results showed that the lake level decreased at the rate of 0.08 m/a from 1958 to 2004 and increased at the rate of 0.16 m/a from 2004 to 2018.The lake volume decreased by 105.40×10^(8)m^(3)from 1958 to 2004,with the rate of 2.24×10^(8)m^(3)/a,whereas it increased by 74.02×10^(8)m^(3)from 2004 to 2018,with the rate of 4.66×10^(8)m^(3)/a.Further,the climate of the Qinghai Lake Basin changed from warm-dry to warm-humid.From 1958 to 2018,the increase in precipitation and the decrease in evaporation controlled the change of the lake volume,which were the main climatic factors affecting the lake volume change.From 1977 to 2018,the measured water yield showed an"increase-decrease-increase"fluctuation in the Qinghai Lake Basin.The effects of climate change and LUCC on the measured water yield were obviously different.From 1977 to 2018,the contribution rate of LUCC was-0.76%and that of climate change was 100.76%;the corresponding rates were 8.57%and 91.43%from 1977 to 2004,respectively,and-4.25%and 104.25%from 2004 to 2018,respectively.Quantitative analysis of the effects and contribution rates of climate change and LUCC on the Qinghai Lake volume revealed the scientific significance of climate change and LUCC,as well as their individual and combined effects in the Qinghai Lake Basin and on the QTP.This study can contribute to the water resources management and regional sustainable development of the Qinghai Lake Basin.
