Analysis Of Eolution And Reason Of Ecosystem Functions Of The Jilin Section Of Liaohe River During The Eleventh Five-Year Plan

Ecological system not only supplies many service functions for human living andsocial development，but also maintains life material circulation and hydrological cycleon earth. It maintains the diversity of biological species and has abilities of climateregulation，water conservation，and environment purification. However， in recentyears， with the continuous development of economy， the ecological environment ofthe Jilin section of Liaohe River has been damaged by a certain degree.Forest resources have been massivily deforested.Rare plants and animals areendangered. The ecosystem gradually lost its ability for self-adjustment and its servicefunctions for human living. Based on the situation，the thesis has detailedly studiedbiodiversity maintaining，soil conservation，water conservation and windbreak andsand-fixation functions in this area. Through the use of GIS and RS technologies andcombined with the social and economic development of Jilin section of Liaohe River，the reasons for the issue emerged in the development process have been analyzed. Thecorresponding countermeasures and suggestions are provided in the end.Through the study，we found the following problems in this area. The statisticsshow that in the study area，the biodiversity decreased during2005-2010. Thebiodiversity was high，and still below the middle level. In2005，the average amountof water conservation in the study area was1.15×106t. In2010，the number was1.56×106t. The amount of water conservation had increased a little. The overalldistribution of the amount of water conservation trend in the area was low innorthwest and high in southeast. Soil conservation quantity in the study area was3.62×107t in2005，and4.47×107t in2010. The amount of soil conservation also increased. Its distribution trend in the study area was relatively low in northwest andrelatively high in southeast. The average vegetation coverage in the study area was70.49%in2005，and68.84%in2010. From2005to2010，vegetation coveragedecreased in the area. Its overall distribution trend was relatively low in northwestans relatively high in southeast. The ecosystem service function value in LiaoheRiver source area was0.2144in2005and0.2378in2010. After5years，theecosystem service function was increased，and was in a higher situation. The overalldistribution trend of ecosystem service function in the study area is relatively low innorthwest and relatively high in southeast.Ecological environment problems in the study area have been analyzed and somecountermeasures need to be taken. The main reason of ecological environmentimprovement in the study area is that: stable population eases the pressure on theecological environment; rapid economic development in the study area, to realize thesustainable development of social economic and environmental protection; the threeindustrial structures gradually tend to be more reasonable; water conservancy reformwas applied during the11th five-year plan in the study area, obtaining some goodresults; ecological environment is improved, creating favorable conditions forecological environment protection. Some local problems are still existed: rivers andsurface water were seriously polluted, the groundwater quality was poorer; morechemical fertilizers pesticides in the study area, resulting in the water pollution. Thecountermeasures against the problems are including：continue the population control,realizing sustainable development; afforestation, improving the diversity of forestcategory; water quality improvement，decreasing the pollution of water sources;pesticide and chemical fertilizer control, improving the pollution condition.