Regional Variability Analysis Of Water Use And An Integrated Management Dynamic Model

In the case of uneven distribution of water resources in China due to natural causes,increase of water consumption as well as the decline of water quality caused by social reasons,reducing water use intensity and strengthening water resources integrated management are of great significance to the effective utilization of water resources in China.This paper analyzes regional variability in water use intensity in China.Then an Integrated Water Management model is established.The main contents are as follows:(1)Regional variability in water use intensity in China.We extend the IPAT identity to the field of water resources and decompose water use intensity into seven factors:water use in agricultural,industrial,household and ecological sector,exploitation rate of water resources,per capita water resources and population intensity.Those seven factors are condensed into four principle components which contain a large amount of original information and are irrelevant under application of Principle Component Analysis.Those four principle components are respectively the agriculture component of water use,the ecological component of water use,the water supply capacity component and the carrying capacity component of water.Then comprehensive water use intensity is calculated by these four components.The four principal components and the comprehensive intensity are taken as cluster variables.The optimal number of cluster is determined to be three by comparing the F-statistic value.Among the three clustering methods–k-means clustering,fuzzy c-means clustering and Gaussian mixture model,we select the result of k-means clustering to study regional variability in water use intensity in China.Three regional water use intensity patterns are obtained: In cluster1,there are ten provinces which are mainly located in the northwest of China.Those members are comparatively undeveloped.Regions in cluster 1 have the worst performance.Sixteen provinces in cluster 2 are mainly located in the southeast of China.They are developed or moderately developed areas.Water use intensity in this cluster is weaker than that in the cluster 1.Cluster 3 includes five provinces.Those provinces are mainly located in the east of China and are relative economically developed areas in China.They have best performance in water use intensity.Finally we analyze contributors to regional variations in water use intensity.Implications for the water ecological civilization of China are proposed.(2)The Integrated Water Management system is studied from the dynamical system perspective.Based on the complex relationship among risk factor,management factor and total water consumption in an area,an Integrated Water Management dynamical system is established.An Integrated Water Management attractor is obtained.Chaotic dynamics characteristics of the system is studied by using Lyapunov exponents spectrum,bifurcation diagrams and Poincar?e mappings.Abundant chaotic dynamics characteristics of the system are showed.The system is controlled to a limit cycle by controlling the management factor.We find that increasing the strength of the government's control over water resources management conduces the effectiveness of water resource management.