Research On Simulation Of Water Quantity And Water Quality In No-Data Area

With the increasing development of social economy, water resources and water environment issues are also increasingly prominent. It has become a scientific research hotspot at home and abroad using water quality and water yield simulation to make optimal allocation of water resources and further planning and management of water environment. An overview of the study area, hydrological and water quality data are the foundation of water quality and water yield simulation. However, the river which is small scale but has a great impact on local water resources and water environment is lack of basic information. In the condition of the lack of relevant information, simulating the water quantity and quality of study area is very difficult.This paper takes Jiangning District Niushoushan river Basin as study area. The first step we do is to summary relevant research at home and abroad.Basing on the theory of hydrology and other disciplines. We collect data, make field sampling surveys and do laboratory test. Using geographic information systems and remote sensing technologies, we preliminarily discussed the water quality and quantity simulation method of no data area, and build the water quality and quantity model of Niushoushan river basin.Firstly, determining the basin boundary. At this stage, This paper takes Jiangning District Niushoushan river Basin for example, we downloads STRM data of 30m precision of Niushoushan River and its surrounding area. Then we use Global Mapper software platform to make the Terrain contour production, and extract the watershed theory boundary with analyzing the study area watershed topographic features. The next step, we amend the boundary through field investigation. Finally, we determine the watershed boundaries and area. The calculated area of the basin is 47.6 square kilometers.Secondly, researching runoff calculation model of the basin. According to the characteristics of the study area and combining field investigation, we delimit control range of pumping stations in the study area. We classify the study area in accordance with four types of land use classification (the surface of the water, paddy fields, dry land and construction land). By the previous step, we obtain areas of four types of land use of different partitions. Results show that construction land and dry land are the main types of land use in the basin. Their areas are 25.93 square kilometers and 12.49 square kilometers, respectively accounting for 54.5% and 26.3% of the total area. Considering different surface conditions, we divide runoff calculation into four modes, namely water calculation model, paddy calculation model, dry calculation model and construction land calculation model. We calculate runoff of 2005,2006, 2012 and 2013 (January to April). Results show that there is a difference of runoff in different years, and the runoff of different partitions of the same year is also different. Among them the runoff of the river's source is the biggest. We simulate the flow of the outlet section of and compare it with the measured. Results show that the simulated flow curve fits very well with the calculated flow curve, and both the simulated and measured daily average flow values are 0.35m 3/s. So the simulate result is accurate.Thirdly, we select four indicators including permanganate index, ammonia nitrogen, total nitrogen and total phosphorus to evaluate and analyze water quality by using single factor index evaluation and fuzzy comprehensive evaluation. Evaluation results from a single-exponential factor show that ammonia nitrogen and total nitrogen are the major pollution factors of the river. And the sampling point 2 and point 6 are seriously polluted. Fuzzy comprehensive evaluation analysis shows that water quality of sampling point 2, point 3, point 6, and point 10 are poor. Among them sampling point 2 and point 6 are the worst. Analysis of the evaluation results shows that Niushoushan river pollution increases from upstream to downstream gradually.Finally, we generalize Niushoushan river into four sections and build its multi-river water quality model. We calculate the attenuation coefficients of permanganate index, ammonia nitrogen and total phosphorus of Niushoushan river. The results are 0.0559d-1,0.0171 d-1 and 0.0212 d-1. The result is reasonable. We simulate the river water quality of 2013 (January to April). Results show that the concentration curves of four sections have a highly consistent trend. Three kinds of pollutants concentration of section one exceed the standard value of water environment function zones.