Health Assessment Of Jama Wetland In The Lhasa River Drainage Area

Recently years, the ecological environment on the earth has appeared overalldeterioration. Wetland ecosystems also begin to deteriorate. So, the wetland ecosystem healthassessments are very important, they are the foundation of wetland management. Presently,wetland ecosystem health assessments have become the hot issues in the land managementresearch. There have more research concerned with various types of wetland healthassessment, lacking on the Tibetan plateau wetland at home and abroad.Tibetan plateau has unique geographical environment, the extent of the damage issmaller comparing with other wetlands on the earth, but in recent years, with the influences ofthe global climate changes and the human interferences, plateau wetlands have already beendestroyed in varying degrees and appeared the degradation trend. This paper chooses Jamawetland as representative area in Lhasa River drainage area of Tibetan Plateau, evaluatesecosystem health, clears the wetland health level and existing problems. The study providestheoretical reference and method for plateau wetland ecosystem health assessment, at thesame time provide important scientific basis for plateau wetland management, protection andsustainable utilization.This article evaluates ecological health from the whole and component two levels toevaluate and from the ecological structure, function and benefit to build index system. Theselected specific indicators include water quality type, natural soil moisture content, organicmatter, total nitrogen, available nitrogen, available phosphorus content, plant communitycoverage, plant species, soil animal abundance, wetland water supply condition, threatenedstatus of wetland, water purifying capacity, tourism carrying capacity, tourism income,population density, illiteracy rate, high school or above degree ratio, herdsman per capitaincome, policies and regulations etc.This paper used the previous research results on wetland health assessment as reference,at the same time according to the characteristics of the Jama wetland, combined multivariatedata of remote sensing image, field measurement and social and economic indicators, used theevaluation index, the Delphi method and analytic hierarchy process method for dataprocessing and analysis, obtained four grades of health level of Jama wetland, healthy,sub-healthy, general sick and disease. The area proportion of each grade was as follows,44.02percent was healthy,33.86percent was sub-healthy,15.31percent was general sick and6.81percent was disease. The results show that, in Jama wetland the land ecosystem health wereoverall well. Health level was sub-healthy. This result matched the actual that Jama wetlandlocated in the Qinghai-Tibet Plateau, the Lhasa River drainage area. The climate was cold,sparsely populated, its destruction and disturbance was very small. The influence factors towetland health were many factors, but the wetland water reduction was the main reasonswhich lead all index of wetland habitat to be changed.According to the evaluation result, Jama wetland ecological protection and managementshould begin from the policy and educations firstly, that make the local people consciouslyprotect the wetland environment. Control the local people unreasonable behavior that usedwater. We should also consider in the wetland downstream outlet to build dam, storage water,provide the necessary engineering measures for wetland water storage, at same time reducegrazing on vegetation, in order to prevent further deterioration of wetland and thus better usethe wetland ecological, social and economic benefit.