Study On The Diagnosis And Evaluation Of Regional Water Resources Carrying Capacity Based On Connection Number

In recent years,due to the rapid expansion of city population,rapid economic and social development in many areas,the development and utilization of water resources in many areas is close to or even more than the upper limit of the local water resources,the shortage of water resources is becoming more and more prominent and restricts the sustainable development of regional society and economy.The diagnosis and evaluation of water resources carrying capacity can provide the basis for identifying and regulating water resources overloading factors in the process of water resource management,and it has important practical significance to promote human water harmony and realize regional sustainable development.The paper is based on the analysis and induction of the concept of water resources carrying capacity diagnosis and evaluation,we build a diagnosis and evaluation model of regional water resources carrying capacity based on the number of connections,and the set pair subtractive situation was used to identify vulnerability indexes.The model is applied to the study of the dynamic diagnostic evaluation and the spatial differential diagnosis analysis of the water resources carrying capacity of Anhui province.In order to predict diagnosis of the regional water resources carrying capacity,we set up a combination prediction model for the diagnosis index of regional water resources carrying capacity based on connection number.The following main achievements have been achieved:(1)We set a diagnosis and evaluation model of regional water resources carrying capacity based on the connection number,and study the dynamic diagnosis and evaluation of the water resources carrying capacity of Anhui province.For this study we have a new research idea,first,we evaluated the overall status of the water resources carrying capacity.Second,we identified vulnerability indexes based on the evaluation results.And then we regulated the vulnerability indexes to make them invulnerability.At last,we reevaluated of water resources carrying capacity.The results shows that the comprehensive evaluation grade of water resources carrying capacity in Anhui Province from 2005 to 2015 is near the grade 2,and it has been developed to a certain extent,but there is a tendency to improve slowly.After the vulnerability indexes are regulated,the evaluation results are significantly better than before.(2)We use the model to diagnose the spatial difference of the water resources carrying capacity of Anhui province.The results shows that the water resources in Jiangnan area of Anhui province are the best,followed by the Jianghuai area,and the water resources in Huaibei area are the worst.For subsystems,the water resource carrying capacity support subsystem of Jiangnan area is the best,followed by the Jianghuai area,and the Huaibei area is the worst but it`s water resources carrying capacity pressure subsystem is the least.For indexes,per capita water resources is the main index leading to the spatial difference of water resources carrying capacity in Anhui Province.(3)Based on the establishment of BP neural network,multivariate linear regression and support vector machine model(SVM)for predicting the diagnostic index of regional water resources carrying capacity,we construct a combination prediction model of regional water resources carrying capacity based on the number of connections(CNCF).The result shows that the SPA-CF model combines the advantages of the 3 forecasting methods such as BP neural network,multiple linear regression and support vector machine.In the prediction of diagnostic index of water resources carrying capacity,CNCF overcomes the shortcomings of BP neural network,such as poor extension,multiple linear regression model,low prediction accuracy and poor support vector machine fitting effect.The CNCF model's prediction accuracy is more greatly improved than a single model.In summary,the proposed method based on connection number for regional water resources carrying capacity diagnosis and evaluation,combined forecasting method and research ideas is reasonable and reliable,and has universality.The method can provide an effective method for the comprehensive study of the evaluation,diagnosis and prediction of regional water resources carrying capacity and can provide technical support for the rational allocation and control of regional water resources.And it is also of great significance to the establishment of water resources carrying capacity monitoring and early warning mechanism.