Study On Evaluation Of Water Resources Carrying Capacity In Coastal Regions

Water resources is not only one of natural resources of controlling ecological environment,and is the substance base of all society development,but also is a strategic economic resource.It is also an important component of comprehensive national strength of a country.With socioeconomic development and population growth,under the drive of enormous water demant,people exploits and utilizes water resources on a large scale continually and discharges a vast of waste water without being disposed,which not only result in the amount of water resources decreasing rapidly and the quality of water resources falling gradually,but also affect hydrologic cycle and renewability of water resources.And these have brought forth severe water problems and water resources crisis to many countries and regions.Water even becomes a limiting factor that plays a critical role in substainable development in many water-shortage areas.How is the status of water resources carrying capacity in a region? And what levels of the economic development and social development can it sustain,which is the condition of water resources in this region? All these have been the yardwand of constituting sustainable development programming and goal.Therefore,it is being of great academic and practical significance to study on the evaluation of water resources carrying capacity.In this dissertation,taking Dalian as study region,we study on evaluation of water resources carrying capacity in coastal regions.The main study contents and conclusions are as follows:(1) Analysis and description of some fundamental conceptions and theories of evaluation of water resources carrying capacity.There has not been perfect theory system for the study on water resources carrying capacity.So in this dissertation only some close theories are analyzed and described:Definition,connotation,characteristics,and influence factors of water resources carrying capacity are analyzed;the relationship between water resources carrying capacity and sustainable development is described;and relationship between the sbusystems of water resources-society-economy-ecological environment compound system are analyzed.(2) The status of water resources,society and economy development,and ecological environment in Dalian.In order to practically embody the core content of this dissertation,we take Dalian as study region.By collecting the related data,the status of water resources, society and economy decelopment,and ecological environment in Dalian are introduced and summarized. (3) Study on evaluation indicators system for water resources carrying capacity in coastal regions.The evaluation indicators system eatablished can describe the water resources carrying capacity and its status,which is more suitable for the design trend of the evaluation indicators system for water resources carrying capacity.Conforming this trend,the evaluation indicators system for water resources carrying capacity in coastal regions is established, which comprises two sub-indicator-systems:One consists of two indicators,maximal economy scale and maximal population scale sustained by water resources,which reflect the size of water resources carrying capacity;Another also can be called comprehensive evaluation indicators system for water resources carrying capacity composed of five hierarchy cellular systems,which reflects the status of water resources carrying capacity by the indicator——status coefficient of water resources carrying capacity,and this coefficient is reflected by carrying capacity coefficient and harmoniousness coefficient.At present,it is of great subjectivity in establishing comprehensive evaluation indicators system for water resources carrying capacity.There have no operational steps to select indicators,and have no feasible selection framework and analysis method to establish evaluation indicators system. The spirit of Entity-Relationship modeling proposed by Peter P.Chen is that supports the specification of "is-a" generalization hierarchy.Based on the construction rules of Entity-Relationship model,the conceptional data model of the problem can be obtained.In this dissertation,based on the Entity-Relationship Appoach,the indicators on subsystems of water resources carrying capacity compound system and their relationships are selected,and then the conceptional framework of comprehensive evaluation indicators system for water resources carrying capacity is established.Combined with the actual conditions of study regions,39 indicators are selected,and the evaluation indicators system for water resources carrying capacity is established under guidance of this conceptional framework.This approach provides an operational steps that can be followed for the selection of indicators on water resources carrying capacity compound system.The conceptional framework has a certain universality to the selection of indicators that compose comprehensive evaluation indicators system of water resources carrying capacity.(4) Study on standard values of indicators.In order to quantitative describing the status of water resources carrying capacity,the status of water resources carrying capacity is classified as the highest level,high level,middle level,low level and the lowest level.And the standard values of 39 indicators of 5 levels are designed and given.These indicators standard values also can be as the basal data or supporting data for some comprehensive evaluation methods' flexible application in comprehensive evaluation of water resources carrying capacity.And these warranties and train of thoughts can provide reference for the design of evaluating indicator standard values in other fields,and even some standard values of indicators can be used directly.(5) Study on method of comprehensive evaluation of water resources carrying capacity. Model and corresponding method of comprehensive evaluation of water resources carrying capacity should be selected according to the characteristics of evaluation indicators system. According to the hierarchical characteristics of the evaluation indicators system and interval characteristics of the indicator standard values,variable fuzzy sets theory and cellular systems theory of fuzzy analysis proposed by Chen Shouyu are introduced into comprehensive evaluation of water resources carrying capacity.The multi-hierarchy variable fuzzy comprehensive evaluation method is proposed on basis of giving relative proportion function model,which can scientifically identify the relative membership degree between sample(study region) indicator and standard value interval of each level indicator,and which can reasonably determine the evaluation level of each sample by varying model and its parameters.This method provides a new quantitative evaluation tool for evaluation water resources carrying capacity,and also perfects and develops variable fuzzy sets theory.(6) Study on evaluation of water resources carrying capacity in Dalian.The evaluation indicators system for water resources carrying capacity in coastal regions,evaluation models, and the multi-hierarchy variable fuzzy comprehensive evaluation method are applied to evaluate the water resources carrying capacity of Dalian and its subdistricts(south of Jinzhou, Wafangdian,Pulandian,Zhuanghe,Changhai) in the actuality year of 2005 and the planning year of 2010.The case study proves that the evaluation indicators system and the models and methods are reasonable and feasible,and that results can provide reference for Dalian working out sustainable development strategy and implementation plan.(7) Study on ways to improve water resources carrying capacity of Dalian.On the basis of analysis of sea ice resources advantage of Dalian,and based on land-ocean synergistic principle in the development of water resources,taking increased water resources quantity of Dalian as starting point,a feasible way to improve water resources carrying capacity by synergy of the artificial runoff obtained by sea ice desalination regulation and the existing natural runoff regulation of Biliuhe reservoir and Yingnahe reservoir of Dalian,is put forward.Lastly,the conclusions are given and some problems to be further studied are discussed.