Studies On Ecological Security Assessment Of The Caohai Plateau Lake Wetland

In this paper, I take Caohai plateau lake wetland as the object of the research, withcombined the domestic and foreign ecological security and ecological safety of wetland,to construction ecological security evaluation index system of Caohai wetland andassessment the present situation of ecological security, find out the major threats andexplore the countermeasures. This article start with the definition of ecological safety,based on the pressure state response (PSR)----conceptual model, selects13indicatorsof2003to2008constructed wetland ecological security evaluation index system, withthe standardization of range and entropy method to determine evaluation index valueand its weight value, using the single factor evaluation and comprehensive evaluationmethod for wetland ecological security evaluation, analysis the impact of variousindicators for Caohai wetland ecosystem.Results of the present study are in the following:①Pressure index safety degree:In the pressure index, soil erosion area is the lowest index, for it is very unsafe in6years, but the grade of ecological security is gradually improved. Therefore, soil erosionis still recovering from the Caohai wetland ecological functions of long focus control;water resources per capita in2007to2008is improved, from safety improvement to theideal state; Cultivated area per capita is less safe grade, which is another potential threatfactor needs to take caused seriously; There are no significant changes in the amount ofsewage discharge per capita and the density of population in the6year period, but alsoshow that these two factors had not obtained the effective control.②State index of safety degreeOn the whole，state indicator is much better compared to the pressure index, one ofthe lowest index is biodiversity index, Caohai wetland is a National Nature Reserve, sothe protection zone of animals and plants ecological safety evaluation standards ishigher than others, which is composed of the biodiversity index of ecological security of low is one of the main reasons. secondly, the indicators in2003to2008，the6yearsthere is not much change, relevant departments for Caohai wetland reserve biodiversityprotection do a lot of work to solve it; The grade of ecological security change index issoil erosion modulus, the natural population growth rate, per capita net income netincome of average per capita, from2003close unsafe and not security level edge, to2008close to a safe level, have very big breakthrough, the main factors to be attributedto in recent years due to the state of the development of the western region ’s attention,with the Guizhou provincial government for the development of Weining regioneconomy drive, per capita income rises to, from several hundred yuan to now2000multivariate; Soil erosion modulus is also improved, from2003to2005is in not safegrade and from2006~2008years is in less security level, which is largely because ofthe vegetation coverage contribution; Vegetation coverage from2005to2008changetendency is obvious, in the safety grade in2008.③Response of indices:In response to the three indicators are rendered gradually become the good trend.Among them, index of environmental governance investment trend of maximum,2003grade of ecological security in the less safety grade in2004to2006,the grade ofecological security to security,2007~2008grade of ecological security for ideal; indexGDP per capita from less safety grade gradually transformed into a security level, this isthe grass sea nature protection area located in Weining county economic developmentresults; the tertiary industry proportion index changes a little.Evaluation results show that from2003to2007level of ecological safety of caohaiwetland is in the unsafe grade, but the overall trend in improved year by year, until the2008into the less secure level, indicating that high level of ecological safety of caohaiwetlands, and the other advanced large urban wetland ecological security state gap isnot small. The reason, ecological safety of caohai wetlands status and ecosystemdestruction because of human rational exploitation of waters and the surrounding,resulting in caohai wetlands degradation of ecosystem function. However, in recentyears, the caohai growing attention, managers and joint efforts of local residents duringthe caohai wetlands ecological systems were improved, in particular wetland ecologicalsecurity levels significantly increase in2008.