| Houhe River Basin, within the crater lake and fen peat wetlands dotted, located inLonggang Volcanic Clusters Region of Changbai Mountain, is a typical water source regionof the Changbai Mountain, as well as one important source of the Second Songhua River,and is also the centre region of Longwan National Nature Reserve. The basin includes specialgeological formations, complex and diverse landforms such as forests, wetlands, rivers,Crater Lake and other natural geographical units, where developed a wetland owing largepeat reserves-the Jinchuan wetland. So there is great ecological significance of the basinprotection.The main conclusions of the study are as follows:(1) The classification system of watershed land use/cover types was established and theland use/cover information was extracted on the basis of interpreting four remote sensingimages of1980,1991,2000and2011Landsat TM image, topographic maps and forest map.The spatial characteristic changes of the study area during31years were gradually in-deepanalyzed by using remote sensing interpretation data, GIS spatial analysis and dynamicchanges measurement mode. Meanwhile the Landscape Pattern Indexes were used to analyzethe landscape pattern transformation characters on the type and landscape level. The changesof basin landscape pattern and types indicate: the landscape types of Houhe River basin werenot changed; the main changes were the landscapes proportions and the spatial pattern. Theprocess of landscape evolution was that residential land area increased, paddy fields areadeclined, dry farmland firstly rapidly increased and then slightly reduced, wetland depredatedfirst and then stabilized, forest area slightly increased volatility, but not much. Dynamicconversion process indicates that the basin landscape type changes include the two-waychange of increase and decrease. On the landscape level, human activities impact on thelandscape pattern made it tends to be shaped because of the human aims; on the plaque level,paddy fields, dry farmland and residential areas changed dramatically, which interferedobviously.(2) The annual change character of regional meteorological factors was analyze in thispaper. MIKE SHE hydrological modeling software was used to set up the evapotranspirationempirical model, which coupling the maximum temperature, minimum temperature,humidity, wind speed, precipitation and other meteorological factors, in order to calculate thebasin potential evaporation capacity, and the relationship between precipitation andevapotranspiration. According to the result above, the reduce trend of water resources in thebasin under current climate condition was described. The reason of landscape type transformation in the basin is complex, which can be concluded in two dominations of moreintensive human activities and climate change. Climatic factor in the period changes slightly,therefore, that human activities were the main dominate driving force for dynamictransformation of landscape pattern.(3)On the basis of the above work, the ecological system value was evaluated and aseries of evaluation indicators reflecting the level of ecological and economic yield wereestablished depend on the emergy theory and method. According to Emergy analysismethods and procedures, model of ecological economic systems related with landscapepattern transformation was constructed separately. The emergy indicators was used toevaluate system input-output level, and then explain the purpose of human activitiestransferring landscape pattern on the foundations of ecological economic changes due tolandscape transformation from1980to2000. The results show that: the total emergy inputsand outputs were obvious different between every sub-landscape system in unit area, themost input landscape per unit was residents, lakes, paddy fields and dry fields followed butfar lower than the former, the lowest was wetland and forest; The difference between everylandscape unit yield is large, residents and lakes highest, wetlands, forests and paddy fieldsSecondly, dry farmland lowest. On the aspect of overall ecological and economic benefitsof the study area, landscape pattern change lead to economic benefits increase of2.83×107US$, the ecological benefits reduction of1.07×107US$, total emergy yield increaseof1.03×1020sej. Economic yield increased significantly, but the ecological yield wassignificantly reduced. The emergy indexes first decreased and then increased. In the entirestudy period, the ecological, economic and ecological system sustainable development indexvalue tended to decrease. Therefore Houhe River basin Landscape pattern change lead to theeconomic benefits growth, but very obvious damage to the ecological environment,meanwhile the sustainable development space was narrowing.(4)On the basis of the pattern structure and function studies, the main ecosystemservices function of houhe river basin was determined, which consist with basic services andsocial services, corresponding value of base value (the value of the substance, process value,existence value) and social values (aesthetic value, cultural value of scientific research,etc.)separately. The Houhe river ecological function values of1980,1991,2000and2011were evaluated by making use of the effective value classification and reasonable evaluationmethod, including the market price method, expenditure method, shadow project method, theproductivity change method, human capital method, the production function method and theecological value method. The results suggest that between1980and2011,the total value ofhouhe river basin significantly fluctuated. landscape pattern transformation owing to humanactivities significantly affect the watershed ecosystem services function. Basin totalecosystem services value quantity decreased significantly from1980to1991, separately390050.06×104US$and1991396550.68×104US$, and decreased continuously after1991, in2000the total value was387616.09×104US$, and then in2011recovered to 392722.75×104US$respectively, decrease of2.25%and0.97%respectively compared with1991. In the aspect of value composition, support service function is the largest, accountingfor about99%of the entire ecosystem services, Second is regulation services, followed bythe production supply services and cultural services. The composition indicates that apartfrom the support service which is the material basic of nature ecosystem, ecologicalprocess make the largest impact on the entire value, Culture service value, mainly consistedof scientific research and leisure service, is a subsidiary function of system. Even thoughagricultural production activities make a great impact on the landscape transformationprocess, value contribution is much less than the natural ecological system.(5)The comprehensive health assessment of Houhe River basin ecosystem was madeby utilizing the pressure-state-response model (PSR model), on the base of the latelyresearch achievement of domestic and foreign scholars on the ecosystem health assessment.The indexes of PSR model include the human disturbance index and population densityindex. status indicators were selected from the organization, vitality, functionality andflexibility aspects of landscape diversity, and average plaque area index, hydrologicalregulation index biodiversity conservation index net primary productivity index, flexibilityindex and pollutants purification index, to reflect the structure and function of the ecosystem.fragmentation index and the economic rate of return index were choose as houhe river basinecology system health evaluation index, using analytical hierarchy process to weight thesorted indicators, and then calculate comprehensive evaluation index. The final result ofcomprehensive Assessment Index in1980,1991,2000,2011is0.7750、0.7667、0.7189、0.7492respectively. According to the index classification level of ecosystem health, thehealth value of Houhe River basin is belong the interval of0.7to0.9, that means, at presenthuman activities governed by the policies and economic development is the main influencingfactors of the basin ecosystem health; basin ecosystem to be some changes, but still maintaina nature state; landscape pattern is relatively stable and the structure relatively reasonable,system vitality relatively strong, pressure relatively light; the basin can still play normalecosystem functions, system is still stable; the basin ecosystem health is staying on a goodlevel. |
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