Study On Optimizing Groundwater Monitoring Network Of Plain In Huang Shui River Basin

The establishment and monitoring work of groundwater monitoring network has a rather long history and has accumulated a lot of datas. These monitoring datas has made a due contribution to scientific evaluation and management of groundwater resources. But there are many problems of groundwater monitoring network used currently because of the subjective and objective reasons. It is difficult to adapt to the needs of information in society today, specifically manifesting as low density of the whole observation wells network and high density in some local. So the existing groundwater monitoring network needs to be optimized.At present, there are many ways to optimize the groundwater monitoring network, such as hydro-geological analysis method, Kriging method, cluster analysis method, entropy method, Kalman filtering method, mathematical programming model law method, in which the hydro-geological analysis is the basis way.Kriging method is a method that solves the best, linear, unbiased interpolation estimators of spatial and temporal distribution variables. It gives certain weights to the measured dates on the surrounding known points to estimate the water lever values of estimated points, after structural analysis according to the measured datas of the known water level monitoring points. Kriging method can not only make full use of all the relevant information on the monitoring network, but also give the variance of error theory. A threshold of variance valueσ₀² is set according to the actual needs and every theoretical variance valueσ² is calculated by using the existing monitoring dates. Ifσ² is biger thanσ₀² , well density is too small and need to increase some wells, otherwise it is too large and need to close some ones.In this paper, the interpolation optimization model of groundwater monitoring network and its solution process are established based on Kriging method. Three alternative programs are found by using this model to optimize the groundwater level monitoring network of Huang Shui River basin plain area. Then the paper chooses the best program On the basis of meeting Well Accuracy while spending the least money. Although it will be possible to achieve more precise monitoring network testing standards by reserving on the 9th and 14 wells, the monitoring costs will increase. While the monitoring costs will reduce by closing the 9th and 14 wells, but monitoring network monitoring accuracy will not be able to reach. Comprehensively considering the local conditions, the 14th well should be closed while the 9th well reserved. The final optimization result is that increases 23 monitoring wells in the low-density aeras and closes the 14th well. Kriging interpolation model is an effective way to optimize the density of groundwater monitoring network, because it fully consider the impact of hydro-geological conditions.Features and innovations in this paper is as following: (1) Proposing the existing groundwater monitoring network deficiencies after survey; (2) Establishing the interpolation optimization model of groundwater monitoring network and its solution process on the basis of Kriging theory.