In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT...In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT) model. The model was tested at the Juntanghu watershed on the northern slope of the Tian Shan Mountains, Xinjiang,China. We compared the performances of temperature-index method and energy balanced method in SWAT model by taking Juntanghu river basin as an application example(as the simulation experiment was conducted in Juntanghu River, we call the energy balanced method as SWAT-JTH). The results suggest that the SWAT snowmelt model had overall Nash-Sutcliffe efficiency(NSE) coefficients ranging from 0.61 to 0.85 while the physical based approach had NSE coefficients ranging from 0.58 to0.69. Overall, on monthly scale, the SWAT model provides better results than that from the SWAT-JTH model. However, results generated from both methods seem to be fairly close at a daily scale. Thestructure of the temperature-index method is simple and produces reasonable simulation results if the parameters are well within empirical ranges. Although the data requirement for the energy balance method in current observation is difficult to meet and the existence of uncertainty is associated with the experimental approaches of physical processes, the SWAT-JTH model still produced a reasonably high NSE. We conclude that using temperature-index methods to simulate the snowmelt process is sufficient, but the energy balance-based model is still a good choice to simulate extreme weather conditions especially when the required data input for the model is acquired.展开更多
Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper t...Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rims sustainable development. Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.展开更多
The population system is the only subsystem tha has charecteristic of subjectivity in theregional PRED system. Influenced by the particular status quo of natural resources and environmentconditions, the population sub...The population system is the only subsystem tha has charecteristic of subjectivity in theregional PRED system. Influenced by the particular status quo of natural resources and environmentconditions, the population subsystem of the Qaidam Basin is very different from those of otherregions'. Based on the on-the-spot investigation to the Qaidam Basin in July 1997, the authors of thispaper sum up several characters of the population subsystem of the Basin. (1) Population mainlyconsisting of the big volume of immigrants and floating population increases very fast. (2) With highpopulation mobility there was great discrepany between the actual number of population (aggregatepopulation) and the statidtical population. (3) Degree of urbanization is very high, and employmentconcentrates mainly on the industrial and teftiary industrial sectors. (4) Sex ratio remains veryunbalanced, especially in the youth group of population which exerts high pressure on employmentand training because of the young age structure. (5) Population quality is relatively high as a wholeWhile educahonal level characterizes the undeveloped regions. In order to predict the futurepopulation of the Basin. according to the characters of population system, this paper puts forward away called dividing-steps-forecast-sum to do the prediction till 2050, use both modeling forecastingmethod and empirical evaluation. The results indicated that the total population of the Basin whllreach 1 .28 million in 2050. Among them, the natural increment and immigrant and floating incrementoccupy 34.99% and 60.86%, respectively, with another 4.13% of special population. In terms ofcharactedstics of population and predicted results as well as the status quo of natural resources andenvironment this paper suggests several thoughts to optimize and adjust the population system of theQaidam Basin. They are, firsuy, to control the number of population as well as improve thepopulation quality, and secondly, to reghate the floating population to assort them withsocioeconomic development in the Basin. Above all, the most important step is to throw high level ofscience and techniqte into the Basin's socioeconomic system to enhance the carrying capacity ofresources and environment and improve the coordinated relationship among population, resources andcnvironment展开更多
基金financially supported by the Ministry of Water Resources (MWR) public sector research and special funds-the most stringent in arid zone water resources management key technologies (201301103)National Nature Science Foundation of China (NSFC) under Grant No. 41130641, 41201025+1 种基金Ministry of Education Key Laboratory of Eco-Oasis Open Topic-Moisture change in Central Asia and its influence on precipitation in Xinjang Province (XJDX0201-2013-07)the Tianshan Scholar Start-up Fund provided by Xinjiang University
文摘In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT) model. The model was tested at the Juntanghu watershed on the northern slope of the Tian Shan Mountains, Xinjiang,China. We compared the performances of temperature-index method and energy balanced method in SWAT model by taking Juntanghu river basin as an application example(as the simulation experiment was conducted in Juntanghu River, we call the energy balanced method as SWAT-JTH). The results suggest that the SWAT snowmelt model had overall Nash-Sutcliffe efficiency(NSE) coefficients ranging from 0.61 to 0.85 while the physical based approach had NSE coefficients ranging from 0.58 to0.69. Overall, on monthly scale, the SWAT model provides better results than that from the SWAT-JTH model. However, results generated from both methods seem to be fairly close at a daily scale. Thestructure of the temperature-index method is simple and produces reasonable simulation results if the parameters are well within empirical ranges. Although the data requirement for the energy balance method in current observation is difficult to meet and the existence of uncertainty is associated with the experimental approaches of physical processes, the SWAT-JTH model still produced a reasonably high NSE. We conclude that using temperature-index methods to simulate the snowmelt process is sufficient, but the energy balance-based model is still a good choice to simulate extreme weather conditions especially when the required data input for the model is acquired.
基金The National Natural Science Foundation of China No. 49971037
文摘Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rims sustainable development. Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.
文摘The population system is the only subsystem tha has charecteristic of subjectivity in theregional PRED system. Influenced by the particular status quo of natural resources and environmentconditions, the population subsystem of the Qaidam Basin is very different from those of otherregions'. Based on the on-the-spot investigation to the Qaidam Basin in July 1997, the authors of thispaper sum up several characters of the population subsystem of the Basin. (1) Population mainlyconsisting of the big volume of immigrants and floating population increases very fast. (2) With highpopulation mobility there was great discrepany between the actual number of population (aggregatepopulation) and the statidtical population. (3) Degree of urbanization is very high, and employmentconcentrates mainly on the industrial and teftiary industrial sectors. (4) Sex ratio remains veryunbalanced, especially in the youth group of population which exerts high pressure on employmentand training because of the young age structure. (5) Population quality is relatively high as a wholeWhile educahonal level characterizes the undeveloped regions. In order to predict the futurepopulation of the Basin. according to the characters of population system, this paper puts forward away called dividing-steps-forecast-sum to do the prediction till 2050, use both modeling forecastingmethod and empirical evaluation. The results indicated that the total population of the Basin whllreach 1 .28 million in 2050. Among them, the natural increment and immigrant and floating incrementoccupy 34.99% and 60.86%, respectively, with another 4.13% of special population. In terms ofcharactedstics of population and predicted results as well as the status quo of natural resources andenvironment this paper suggests several thoughts to optimize and adjust the population system of theQaidam Basin. They are, firsuy, to control the number of population as well as improve thepopulation quality, and secondly, to reghate the floating population to assort them withsocioeconomic development in the Basin. Above all, the most important step is to throw high level ofscience and techniqte into the Basin's socioeconomic system to enhance the carrying capacity ofresources and environment and improve the coordinated relationship among population, resources andcnvironment
