Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturba...Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturbance on drinking water and natural resources. Effective communication and knowledge exchange across scientists and stakeholders (i.e., drinking water managers) is essential for constructively responding to such landscape scale disturbances, providing improved adaptive capacity through knowledge sharing. An assessment of stakeholder knowledge levels, information needs, primary concerns, and suggested communication strategies were conducted via an online elicitation survey and World Science Café workshops. Knowledge levels, assessed via a survey of local water managers and experts, were relatively low with approximately half of the respondents reporting little to no knowledge of the effects of mountain pine beetle on drinking water quality and quantity, thereby indicating limited knowledge exchange between scientists and drinking water stakeholders. Increased accessibility and dissemination of research findings pertinent to the mountain pine beetle epidemic’s effects on drinking water quality and quantity is necessary for natural resource management. Recommendations for improved communication among scientists and drinking water stakeholders in particular and forest health in general include dispersal of non-academic research summaries, information exchange through existing media and community resources, demonstration projects, and information clearinghouses. This information provides a better understanding of the challenges, concerns, and first-hand experience of stakeholders of a landscape disturbance issue to apply this knowledge to enhance land management practice and how researchers on this overall project enhanced science communication efforts.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
In this study,FLUENT software was employed to simulate the flow pattern and water depth changes in a 120° sharp bend at four discharge rates.To verify the numerical model,a 90° sharp bend was first modeled w...In this study,FLUENT software was employed to simulate the flow pattern and water depth changes in a 120° sharp bend at four discharge rates.To verify the numerical model,a 90° sharp bend was first modeled with a three-dimensional numerical model,and the results were compared with available experimental results.Based on the numerical model validation,a 120° bend was simulated.The results show that the rate of increase of the water depth at the cross-section located 40 cm before the bend,compared with the cross-sections located 40 cm and 80 cm after the bend,decreases with the increase of the normal water depth in the 120° curved channel.Moreover,with increasing normal water depth,the dimensionless water depth change decreases at all cross-sections.At the interior cross-sections of the bend,the transverse water depth slope of the inner half-width is always greater than that of the outer half-width of the channel.Hence,the water depth slope is nonlinear at each crosssection in sharp bends.Two equations reflecting the relationships between the maximum and minimum dimensionless water depths and the normal water depth throughout the channel were obtained.展开更多
As is already known, most of the plasma literature is occupied with the plasma instabilities and the inevitable plasma waves, which remain major obstacles to the thermonuclear fusion process. Many experimental data on...As is already known, most of the plasma literature is occupied with the plasma instabilities and the inevitable plasma waves, which remain major obstacles to the thermonuclear fusion process. Many experimental data on the plasma waves (growth or damping) and their accompanied theoretical interpretations have been published during the last five decades; lots of them have been identified and justified as well, some not yet. One of these is our previous research on plasma waves, which originated in the early 80's at the Plasma Physics Laboratory of the NCSR "Demokritos". As the wave rising is defined by the growth rate (or the damping on the extinguishment), these important wavy quantities will be studied in detail in the present paper. Three examples are taken from our previous theoretical results, and the first observation reveals that the involved quantities are complicated enough to be studied by themselves. So, the use of suitable approach models, which may interpret the experimental wavy quantities, is the central idea of the present attempt, Furthermore, calculations with a little change of the initial conditions have been repeated in order to determine whether the plasma behaves as a chaotic medium.展开更多
[Objective] The study aimed to discuss the effects of coal mining subsided water area on temperature change in Huaibei coal mine. [Method] Based on the data of monthly temperature from 1957 to 2007 recorded by Suixi ...[Objective] The study aimed to discuss the effects of coal mining subsided water area on temperature change in Huaibei coal mine. [Method] Based on the data of monthly temperature from 1957 to 2007 recorded by Suixi (coal mining subsided water area) and Fuyang stations (control), the effects of coal mining subsided water area on temperature change in Huaibei coal mine were discussed using linear trend estimation and comparative analysis methods. [Result] Spring, autumn, winter and annual average temperatures of coal mining subsided water area (Suixi) were increased in the last 51 years, and the increase of winter temperature was mostly significant with a tendency rate of 0.49 ℃/10 a. Meanwhile, annual temperature range of coal mining subsided water area was decreased from 1957 to 2007. Temperatures of Suixi in four seasons were lower than those of Fuyang from the 1960s to 1990s, and temperatures of coal mining subsided water area (Suixi) were higher than those of Fuyang in spring, autumn and winter but lower than those of Fuyang in summer from 2000 to 2007. [ Result] Coal mining subsided water area had certain effects on temperature change of Huaibei coal mine.展开更多
Due to its specificity, seasonality and location of large areas, the crops are exposed to the greatest degree of risks posed by climate change. To maintain stability and increase yields, it is imperative to implement ...Due to its specificity, seasonality and location of large areas, the crops are exposed to the greatest degree of risks posed by climate change. To maintain stability and increase yields, it is imperative to implement an innovative approach by which to optimize certain processes such as tillage, sowing and irrigation. The main tasks of innovative solutions are proposed to increase the soil water holding capacities in the root layer over a prolonged period of time, and improve the accuracy of the drilling process for row crops and vegetables by using biodegradable materials, and on this basis to optimize the irrigation by use of specialized software products to determine irrigation scheduling and irrigation requirements.展开更多
The water cycle and water resources within river basins under changing environmental conditions undergo profound changes, which have significant effects on the water environment of the river. Owing to the water resour...The water cycle and water resources within river basins under changing environmental conditions undergo profound changes, which have significant effects on the water environment of the river. Owing to the water resources demanded for economic and social development, water quantity and quality are becoming the core constraints of water resources development and utilization. In this paper, the dual attributes of water resources, progress into research regarding water quantity and quality joint assessment and simulation and the shortcomings associated with these techniques are summarized and described with respect to water quantity and quality. The results indicated that under the current environmental conditions, the method used for traditional water quality assessment of single water bodies cannot meet the requirements for water resources management. Moreover, a coupled hydrodynamic and water quality numerical model for river networks and lakes that applies to the river water environment system was developed for the river network flow and pollutant migration and transformation process and validated. This validation revealed that the error between the simulated values calculated by the model and the monitored values was small, meeting the application requirements and realizing the integrated and dynamic simulation of water quantity and quality of the river water environmental system. On this basis, the integrated simulation model was applied to the Luanhe River Basin.展开更多
文摘Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturbance on drinking water and natural resources. Effective communication and knowledge exchange across scientists and stakeholders (i.e., drinking water managers) is essential for constructively responding to such landscape scale disturbances, providing improved adaptive capacity through knowledge sharing. An assessment of stakeholder knowledge levels, information needs, primary concerns, and suggested communication strategies were conducted via an online elicitation survey and World Science Café workshops. Knowledge levels, assessed via a survey of local water managers and experts, were relatively low with approximately half of the respondents reporting little to no knowledge of the effects of mountain pine beetle on drinking water quality and quantity, thereby indicating limited knowledge exchange between scientists and drinking water stakeholders. Increased accessibility and dissemination of research findings pertinent to the mountain pine beetle epidemic’s effects on drinking water quality and quantity is necessary for natural resource management. Recommendations for improved communication among scientists and drinking water stakeholders in particular and forest health in general include dispersal of non-academic research summaries, information exchange through existing media and community resources, demonstration projects, and information clearinghouses. This information provides a better understanding of the challenges, concerns, and first-hand experience of stakeholders of a landscape disturbance issue to apply this knowledge to enhance land management practice and how researchers on this overall project enhanced science communication efforts.
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.
文摘In this study,FLUENT software was employed to simulate the flow pattern and water depth changes in a 120° sharp bend at four discharge rates.To verify the numerical model,a 90° sharp bend was first modeled with a three-dimensional numerical model,and the results were compared with available experimental results.Based on the numerical model validation,a 120° bend was simulated.The results show that the rate of increase of the water depth at the cross-section located 40 cm before the bend,compared with the cross-sections located 40 cm and 80 cm after the bend,decreases with the increase of the normal water depth in the 120° curved channel.Moreover,with increasing normal water depth,the dimensionless water depth change decreases at all cross-sections.At the interior cross-sections of the bend,the transverse water depth slope of the inner half-width is always greater than that of the outer half-width of the channel.Hence,the water depth slope is nonlinear at each crosssection in sharp bends.Two equations reflecting the relationships between the maximum and minimum dimensionless water depths and the normal water depth throughout the channel were obtained.
文摘As is already known, most of the plasma literature is occupied with the plasma instabilities and the inevitable plasma waves, which remain major obstacles to the thermonuclear fusion process. Many experimental data on the plasma waves (growth or damping) and their accompanied theoretical interpretations have been published during the last five decades; lots of them have been identified and justified as well, some not yet. One of these is our previous research on plasma waves, which originated in the early 80's at the Plasma Physics Laboratory of the NCSR "Demokritos". As the wave rising is defined by the growth rate (or the damping on the extinguishment), these important wavy quantities will be studied in detail in the present paper. Three examples are taken from our previous theoretical results, and the first observation reveals that the involved quantities are complicated enough to be studied by themselves. So, the use of suitable approach models, which may interpret the experimental wavy quantities, is the central idea of the present attempt, Furthermore, calculations with a little change of the initial conditions have been repeated in order to determine whether the plasma behaves as a chaotic medium.
基金Supported by the Key Project of Provincial Natural Science Research for Colleges and Universities in Anhui Province, China ( KJ2013A244)
文摘[Objective] The study aimed to discuss the effects of coal mining subsided water area on temperature change in Huaibei coal mine. [Method] Based on the data of monthly temperature from 1957 to 2007 recorded by Suixi (coal mining subsided water area) and Fuyang stations (control), the effects of coal mining subsided water area on temperature change in Huaibei coal mine were discussed using linear trend estimation and comparative analysis methods. [Result] Spring, autumn, winter and annual average temperatures of coal mining subsided water area (Suixi) were increased in the last 51 years, and the increase of winter temperature was mostly significant with a tendency rate of 0.49 ℃/10 a. Meanwhile, annual temperature range of coal mining subsided water area was decreased from 1957 to 2007. Temperatures of Suixi in four seasons were lower than those of Fuyang from the 1960s to 1990s, and temperatures of coal mining subsided water area (Suixi) were higher than those of Fuyang in spring, autumn and winter but lower than those of Fuyang in summer from 2000 to 2007. [ Result] Coal mining subsided water area had certain effects on temperature change of Huaibei coal mine.
文摘Due to its specificity, seasonality and location of large areas, the crops are exposed to the greatest degree of risks posed by climate change. To maintain stability and increase yields, it is imperative to implement an innovative approach by which to optimize certain processes such as tillage, sowing and irrigation. The main tasks of innovative solutions are proposed to increase the soil water holding capacities in the root layer over a prolonged period of time, and improve the accuracy of the drilling process for row crops and vegetables by using biodegradable materials, and on this basis to optimize the irrigation by use of specialized software products to determine irrigation scheduling and irrigation requirements.
基金supported by the National Basic Research Program of China (2006CB403404 and 2010CB951102)the Funds for Creative Research Groups of China (51021066)the National Natural Science Foundation of China (51009150,40830637)
文摘The water cycle and water resources within river basins under changing environmental conditions undergo profound changes, which have significant effects on the water environment of the river. Owing to the water resources demanded for economic and social development, water quantity and quality are becoming the core constraints of water resources development and utilization. In this paper, the dual attributes of water resources, progress into research regarding water quantity and quality joint assessment and simulation and the shortcomings associated with these techniques are summarized and described with respect to water quantity and quality. The results indicated that under the current environmental conditions, the method used for traditional water quality assessment of single water bodies cannot meet the requirements for water resources management. Moreover, a coupled hydrodynamic and water quality numerical model for river networks and lakes that applies to the river water environment system was developed for the river network flow and pollutant migration and transformation process and validated. This validation revealed that the error between the simulated values calculated by the model and the monitored values was small, meeting the application requirements and realizing the integrated and dynamic simulation of water quantity and quality of the river water environmental system. On this basis, the integrated simulation model was applied to the Luanhe River Basin.