松嫩高平原黑土区耕地动态变化特征分析--以黑龙江省巴彦县为例

耕地动态变化特征的研究对耕地保护、整理和开发利用具有极其重要的意义。以巴彦县1991,2006和2009年3期遥感影像为数据源,利用GIS空间分析功能,提取3个时点耕地动态变化数据,分析了该区耕地变化幅度与速度特征、耕地转入转出特征、耕地变化空间分布特征及耕地景观格局分布特征。结果表明,巴彦县3个时点耕地面积持续增加,但年均净增速度却呈现下降趋势。未利用地、林地和建设用地始终是向耕地转变的主要土地利用类型;耕地主要向林地、未利用地、草地和建设用地转变。巴彦县耕地变化空间差异显著,新增耕地主要来自于研究区南部松花江沿岸河漫滩开垦、东北部低山丘陵地区毁林开荒及西北部建设用地转变。耕地斑块数量和斑块密度呈上升趋势,人类干扰程度加大,破碎化程度不断加剧;耕地景观形状指数和分形维数呈下降趋势,耕地景观的斑块形状更趋简单并越来越有规律;较高的耕地景观连通性,表明耕地景观在空间分布上具有较高的聚集度。

An Analysis on Dynamic Characteristics of Cultivated Land in Black Soil Region of the Songnen High Plain-A Case Study of Bayan County in Heilongjiang Province

Study on the dynamic characteristics of cultivated land plays a very important role in protection,consolidation and utilization of cultivated land.By taking remote sensing images in 1991,2006 and 2009 as data source,the characteristics of amplitude and speed,roll-in and roll-out,spatial distribution,and landscape distribution of cultivated land changes were analyzed by means of spatial analysis function of GIS.Results show that the total area of cultivated land increased,but the net annual average speed declined in the three years.Unutilized land,forest land and construction land were the main land use types transformed into cultivated land.Cultivated land was mainly transformed into forest land,unutilized land,grassland and construction land.Spatial differences of cultivated land change in Bayan County were remarkable,and newly increased cultivated land was mainly from the reclaimed floodplain along the Songhua River,deforestation of northeast hilly areas and construction land change in northwest.The number and density of cultivated land plaque tended to increase,human interference extent increased,and fragmentation enlarged.Landscape shape index and fractal dimension tended to decrease and the shape of cultivated land landscape plaque became simpler and more regular.The high connectivity of cultivated land landscape indicated that the spatial distribution of cultivated land landscape had a high degree of aggregation.