Diagnosis And Management Of Drought Pressure Based On Dualistic Water Cycle Simulation Model In Jing River Basin

As a global problem, drought has significantly impacted social development in the world. In China, economic losses caused by drought rank first, which greatly hinders development of agriculture, social economy, animal husbandry and ecological environment construction. As far as agriculture, economic losses caused by drought each year exceed total losses by other natural disasters since the foundation of our country. Furthermore, even nowadays, with the advent of massive highly developed science and technologies, drought is still a formidable problem needs to be solved. Besides, according to relative materials, drought regime has deteriorated in recent years. In order to efficiently alleviate drought, domestic and foreign scholars have already carried out lots of related researches, concerning drought regularity, drought evaluation, drought early warning, drought management and so forth. However, previous researches usually focus on correlation analysis between drought and hydrological factors, underlying surface conditions, climatic patterns, ignoring influences by human activities and ecological factors in the process of drought. Thus, comprehending the exhaustive evolving process of drought becomes scarcely possible, so does its potential effects. Additionally, as for research methods, at one level, due to influences of human activities, consistency of hydrological series has been destroyed. At another level, each impact factor of drought has interacting and mutual transformation relationships. Both of them let the results of analysis become suspicious, so does the forecasting results of merely considering climatic patterns. In this condition, this research takes the Jing river basin as an example, carrying out research to drought decision support system concerning impacts of human activities. The main contents and conclusions are as follows:1. Drought regularity and driving mechanism analysis. From the angle of natural water circulation and social water circulation respectively, this paper analyzes evolutionary regularity of drought regime. To be more specific, in the aspect of natural water circulation, we mainly consider correlations of drought events with factors like climates, weather, low flow and underlying surface conditions while in the aspect of social water circulation, we mainly consider evolution process of volume and structure of water consumption, conditions of water catchment area, diversion and storage project and so on, for the sake of thoroughly revealing the driving mechanism of drought.2. Construction of the drought pressure diagnosis system. On the basis of confirming the drought index selection principle, combining results of driving mechanism analysis, this paper constructs drought pressure diagnosis index system from the angle of meteorology, water catchment regime and surplus-deficit relationships. Furthermore, we introduce obtaining paths and approaches of each index, which is closely bound up to the dualistic water circulation simulation model. Finally, contrasting to current drought evaluation system, we emphasis on the role of human activities in the process of drought, for the purpose of establishing a more scientific, credible index system. As a natural-human dualistic model, the dualistic water cycle simulation model can be an important method to response to the process combing human activities and natural process.3. Establishment of drought pressure development-oriented dualistic water simulation model. Dualistic water cycle simulation is the basis of the diagnosis of drought, the important approach of obtaining indexes.This chapter mainly introduces the process of establishing dualistic water simulation model particularly. Generally speaking, the process of establishing the SWAT(Soil and water assessment tool) hydrological model, the allocation model of water resources and their coupling procedures are expounded here in details, including the coupling temporal scales, the coupling spatial scales, the input and output interfaces and so on.4. Establishment of drought pressure diagnosis system based on dualistic water circulation simulation model. The pressure early warning system blends the diagnosis system and dualistic water cycle system, through the rolling run of drought pressure diagnosis system driving by dualistic water cycle simulation model, combing regulation and controlling approaches, the diagnosis and regulation process based on “evaluation-early warning-early decision-rationality evaluation of the decision-evaluation again”can be achieved, which undoubtedly will assist the scientific quantification of drought management.5. Instance analysis. In this chapter, the established drought pressure diagnosis system is applied to the practical project to verify its rationality. To be specific, we choose a study phase from July 2013 to June 2014. In this phase, we use the established system to manage drought of 27 sub-basins in the study area. Besides, combining to 3 sub-districts of Qingyang District, Pingliang District and Xianyang District, we elaborately analyze the evolving process of regional drought regimes. The research indicates that, at one hand, this drought pressure diagnosis system is scientific and reasonable, the early warning results are reliable. At another hand, the selection of drought-resisting measures, which is closely related to the early warning results, can magnificently alleviate drought regime inside the catchment, thus it can be applied to practical project. Overall, frequent, severe drought usually happens in Jing river basin, it is urgent to implement scientific management measures to reply drought and pay attention to opening up the source and reducing the flow. Additionally, in the condition of having extremely deficient water resources, in order to efficiently alleviate drought regime, the government should adjust the structure of water consumption, such as vigorously developing building industry, light industry, service industry and other low water consumption industries, suitably suppressing heavy industries and other high water consumption industries and encouraging rain-water and waste-water reclamation and reuse. Eventually, the government should also pay attention to main water consumer-agriculture, adjusting irrigation methods like encouraging water saving irrigation, substituting earth canals for impermeable canals, implementing sprinkling irrigation and drip irrigation technologies and so forth.