中文摘要：

东北地区是我国森林、草场资源最为丰富的地区之一。近300年来,耕地扩张、森林砍伐、草地退化等所导致的显著土地覆盖变化会通过对陆-气之间碳通量和地表反照率的改变,进而对气候系统产生影响。该文采用历史文献分析、原始潜在植被恢复等方法,结合驱动力分析,重建了过去300年东北地区林地和草地自然覆盖变化状况。可提供空间分辨率至县、时间分辨率约为100年的东北地区林地和草地覆盖数据,为气候模拟、碳排放估计等相关研究提供真实的历史数据;得到对过去300年,东北地区林地和草地覆盖变化特征的认识：过去300年,东北地区林地、草地所占比例分别减少了约15%、10%;18—19世纪,东北的天然植被覆盖几乎处于原始状态,林地、草地减少的地区主要集中在辽东、辽西等农垦区;1900—1950年为林地、草地减少最为迅速的时期,辽东、辽西的天然植被几乎均被破坏殆尽,鸭绿江流域、长白山地区森林减少十分显著,草地界线已明显向西退缩;20世纪后半期,林地覆盖在空间上呈扩张趋势,局部地区仍在减少,而草地覆盖在空间上则一直呈缩小趋势。

英文摘要：

Northeastern China is one of the regions having the most abundant forest and grass resources in China. During the past 3 centruries（1700-2000）, land cover changes, such as deforestation, grass degeneration, etc. , have influenced the climate system by changing surface albedo and carbon flux between land and atmosphere. This paper uses historical document analysis and reconstruction of original potential vegetation cover combined with driving force analysis to reconstruct forest and grassland cover changes over the past 3 centruries in northeastern China. The authors hope to provide forest and grassland coverage data on spatial resolution of county level and time resolution of approximately 100 years, and also provide real historical data for climate models, carbon emission estimates, and other relative research. Furthermore, greater knowledge was sought about the characteristics of forest and grassland cover changes in northeastern China over the past 300 years： the proportions of forestland and grassland in northeastern China were reduced by approximately 15 % and 10%; during 18-19 centuries, natural vegetation coverage in northeastern China was still nearly at the initial state, the area where the forest and grassland reduced mainly concentrated in agriculture and reclamation areas of eastern and western Liaoning Province; 1900-1950 is the most rapid time of reduction, natural vegetation in eastern and western Liaoning Province was almost completely destroyed, forest reduction in the Yalu River Basin and the Changbai Mountain area was extremely obvious, the grassland distribution flinched obviously to the west; in late half of the 20th century, forest cover showed a trend of spatial expansion except that the part of area was still decreasing, but the grassland cover showed reduction tendency continuously.