Study On The Landscape Pattern Of Land Cover Responds To Climate Change In Heilongjiang Province

The important influence of land cover change on the global environment is graduallyrecognized as the research on global environment change has been going to depth. So theresearch in land use and cover has become hot points in the field of global environment change.And it is a way to synthetically study global and regional environment change in view ofnature and social economy. Comprehensive analyzing the driving mechanism of the nature andculture on land-cover change not only has become a hot topic in recent years through selectingtypical region and revealing the characteristics land cover change by various means, but alsocan provide more abundant and accurate regional information for further studying large scaleregion and the earth.Situated in Northeastern China, Heilongjiang province is sensitive to global climatechange. In this paper, based on analyzing NOAA/AVHRR and MODIS/EOS images and dailymeteorological data, "3S" technologies, landscape ecology theory and statistical model methodare used to study the spatial pattern, the combination characteristic and the dynamic changes ofland cover in Heilongjiang Province. And at the same time, combining the condition ofsocio-economic development, the effect of climate change on land cover change and its mainimpact factors are discussed to reveal the change condition and its driving force. Accordingly,these studies can provide theoretical basis for achieving sustainable development of regionalland resources in Heilongjiang Province. The main conclusions are as follows.①Air temperature in the whole province has a rising trend in the recent 43 years with arising amplitude of 0.88℃. Major warming characteristic is increase in winter and theminimum air temperature, and then is mean daily temperature. At the same time, the size ofdiurnal range is gradually reduced. Extreme low temperature events are declining by 5 per year,but extreme high temperature events are increasing by 2 per year especially by 5 per year afterthe middle of 1990s.②Although precipitation in the whole province has no marked change, the number ofstations with increasing trend of precipitation is more than that with decreasing trend.Precipitation frequency of most stations has a decreasing trend and precipitation intensity hasan opposite trend. With the corresponding change in temperature and precipitation, relativehumidity in the cold-humidity region has a slight increasing trend as a whole, and that in otherclimate regions has slow decreasing trend.③The area of farmland, water, construction land and unused land has increased indifferent degrees. On the contrary, the area of forest land and grassland is reduced from theyear 1993 to 2003. Area with the slow and extreme slow pace of land-cover changes occupies 90 percent in the 10 years. Comprehensive land cover dynamic degree in the descending orderis forest land, farmland, grassland, construction land, water and unused land. The transformbetween each land cover types mainly represents that forest land and grassland transforms tofarmland and farmland transforms to forest land. The centers of all land cover types have beenmigrated differently in the 10 years. The migrating quantity of center of grassland is the biggestwith 0.32km to eastward from north. The migrating quantity of center of grassland is the leastwith 0.03km to eastward from south.④The landscape pattern change of land cover of Heilongjiang Province in recent 10 yearsis studied using landscape ecology. The results show that the patches of forest land, farmlandand grassland tend to fragment gradually at patches level. The patches of other land cover typestend to be mass. And the quantity of patches in 2003 is bigger than that in 1993. At landscapelevel, the landscape diversity in 2003 increased compared with that in 1993. The evidentdecrease of dominance index and the little increase of evenness index lead to the increase offragment and destroy of integral structure of the natural environment. Mean shape index andmean patch fractal dimension in 2003 is smaller than that in 1993. The landscape shapes innatural and half-natural condition tend to be simplifying. And the controlling effect of regionalecology may be enervated.⑤By using canonical correlation analysis method, 8 variables for indicated land coverchange and 23 variables which relevant to the different nature and humane conditions havingbeen chosen, especially the emphasis was focused on the nature variables. Results showed thatland cover change was caused by the interaction of natural factors and human activities inheiiongjiang province, which was strongly controlled by natural factors in northern and wasstrongly controlled by human activities in southern.⑥The change of total cultivated land area and the number of patches were significantlyinfluenced by the lowest temperature, GDP and the primary industry gross output, especiallyeconomical actuation factor influence was bigger than the climatic conditions. The forestryland area and the number of patches were significantly influenced by the lowest temperature,≥10℃accumulated temperature and GDP, in which the lowest temperature factor influencewas bigger than the economic driving factors; The change of total grassland area and theaverage patch size of it were significantly influenced by the≥1.0℃accumulated temperature,frequency of annual precipitation, total population and GDP, especially the impact of climatecondition on it was bigger than the social driving factors; The change of water bodies area andthe unused land area were significantly influenced by GDP. The change of patch diversityabout total built up land were significantly influenced by GDP and the number ofnon-agricultural population.