| The Jing-Hang Grand Canal with a total length of more than1,700km, goes through2,500years in Chinese history. It plays an important role in the field of Canal navigation, militaryaffairs, political affairs and culture. Until now, the part of the Canal from Jining to Hangzhou,which is more than1100km, is still being used. However, the current situation of environmentalong the Canal is disgusting and the human environment is not thought important. The east lineof south to north water transfer project and the application for the world heritage of theJing-Hang Grand Canal provided new chance and challenge to protect its environment. Study onthe variation of environment along the Jing-Hang Grand Canal is of vital importance for itssustainable development as well as cities along the canal.Based on remote sensing inversion of vegetation index of the whole Jing-Hang Grand Canalwithin60km, this study analyzed the vegetation distribution along the canal； in the case of theXuzhou city on the canal, based on remote sensing inversion of temperature and interpretation ofland use, equation between regional forest coverage and regional average surface temperaturewas established; With RegCM3to simulate surface annual average temperature, equationbetween regional forest coverage and regional average annual surface temperature wasestablished; in the case of Yangzhou city, integrated estuary change, river bank change and canalchange with urban change of Yangzhou city, the variation of Yangzhou city within2500yearswas analyzed; in the case of Beijing city, a new human environmental evaluation model wasproposed systematically with cultural and heritage factors. It was integrated with ecologicalenvironment evaluation model to create a synthetic environment assessment model to evaluatethe environment along the Canal of Beijing. The results are as follow:(1)Based on remote sensing inversion of vegetation index of the whole Jing-Hang GrandCanal within60km, as well as the vegetation index from MODIS-NDVI andSPOT/VEGETATION NDVI, this study analyzed the vegetation distribution along the canal. Itshowed that the vegetation index was the highest in the August (0.42) and the lowest in theJanuary (0.18).(2)In the case of the Xuzhou city on the canal, based on remote sensing inversion oftemperature under Arc GIS9.3from remote sensing image on August,11th,1987and August,12th,2006, and interpretation of land use, lad use map and regional average surface temperaturewas acquired and equation between regional forest coverage and regional average surfacetemperature was established. It showed that on August,11th,1987, the max temperaturedifference among seven prefectures was0.98℃, the equation between regional forest coverage and regional average surface temperature was y=-0.2132x+25.769; While on August,11th,2006,the max temperature difference among seven prefectures was3.24℃, which showed on one hand,the increase of extreme surface temperature due to hot island effect in the city area, on the otherhand the decreases of regional average surface temperature in several prefectures due to theincrease of forest. The equation between regional forest coverage and regional average surfacetemperature was y=-0.1044x+30.649.With RegCM3surface annual average temperature was simulate for the period1960-1969and1990-1997. It showed that surface annual average temperature varied between13.6℃-14.1℃in the years from1960-1969,lower than those(13.5℃-14.5℃) in the period form1990-1997.The max surface annual regional temperature in the years1990-1997was0.4℃higher than thatin the years1960-1969while the minimum annual regional temperature in the years1990-1997was0.1℃lower than that in the years from1960-1969. The equation between regional averageannual surface temperature and regional forest coverage for the period1960-1969was:y=0.0201x2-0.3791x+15.398, R2=0.67, showing that for each10%increase of forest coverage,regional average annual surface temperature decreased by0.68℃. That for the period1990-1997was y=-0.0747x+15.229, R2=0.90, showing that for each10%increase of forest coverage,regional average annual surface temperature decreased by0.75℃. On the background of globalwarming, increase of forest coverage in the Xuzhou city controlled regional warming, showinggreat importance in response for global warming.(3)Yangzhou city, which lies besides the north bank of the Yangtze River, was built in theyear B.C.486and the same old as the Grand Canal. Within2500years, it experienced greatdevelopments and changes in several important historical periods (Spring and Autumn, HanDynasty, Jin Dynasty, Tang Dynasty, Song Dynasty, Ming and Qing Dynasties). Based onliterature of historical geography and archaeological data, using the historical geography methodand3S (GIS (Geographic Information System), RS (Remote Sensing) and GPS (GlobalPositioning System)), this study integrated estuary change, river bank change and canal changewith urban change of Yangzhou city. Firstly, the boundary of the Yangzhou city was made on theimages in September2006of the LANDSAT ETM remote sensing data based on itsadministrative map; Then according to history literature and archaeology data, key points for theboundary of the Yangzhou city were selected and located by GPS field observation and stackedwith the RS image, using ArcGIS9.3to simulate the change process of the Yangtze River indifferent periods and acquire its attribute data quantitatively, based on which, characteristics ofurban change were analyzed in six historical periods and the driving factors for the urban changewere discussed.The results showed that climate change was the background of urban changes of theYangzhou city, but these changes were also affected by several other factors. The changes of theYangtze River channel and the Hangou Canal guided the changes of the Yangzhou city. Thespatial changes of the bank of the Yangtze River and of the Hangou Canal in different periods were estimated. The silted area and water area of the Yangtze River within Yangzhou city inhistorical periods were calculated. The changes that took place in the ancient Yangzhou city werecaused by the silt of the Yangtze River moving the bank southward by deposition on its northernbank, which in turn resulted in the necessary extension of the Canal for shipping. The cityextended its area, following the extension of the Canal. Even when the city decreased in size, itdid so by retreating back towards the Canal. In general, before the Tang Dynasty, the city waschanged mainly by natural factors, and after the Tang Dynasty by human factors.(4)Based on GIS and RS, SPOT5RS image data of September in the year2006forBeijing city was interpreted and raster database of land use/vegetation coverage was made.According to the cultural heritage data obtained from field observation as well as the ecologicalcharacteristics along the Grand Canal, a new human environmental evaluation model wasproposed systematically with cultural and heritage factors. It was integrated with ecologicalenvironment evaluation model to create a synthetic environment assessment model to evaluatethe environment along the Canal of Beijing. Results showed that the general environment alongthe Canal was usual, and the area under middle level takes34%of the whole. Correlating withnatural condition, economic development and human environment, its spatial distribution showsthat the synthesis value of environment decreased from the suburb to the urban area. So measuresshould be taken to improve both ecological environment and human environment along the canalin Beijing. The new model was believed useful for the ecological and human environmentassessment of the area along the Jing-Hang Grand Canal for its planning, protection,management and application for the world heritage as well as its sustainable development.
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