土地利用表现为在自然要素和人类活动的综合作用下的一系列异质性的图形。不同的土地利用空间格局的地学形成机制、生态功能、演化方向和对环境的影响各不相同,其空间图形也千差万别。运用景观生态学原理、地理图形信息理论,以位于中国北方农牧交错带的吉林省前郭县作为研究区,在GIS的支持下,归纳、抽象了各主要土地利用类型斑块形状及其描述参数,探讨了土地利用空间格局和空间分布的表达方法(VCM曲线),实现了土地利用空间格局图形的数量化描述和分析。其结果为从图形信息机理的角度研究土地利用格局的地学形成机制及生态功能、时空演化等方面奠定了基础

Heterogeneity in land use is shaped as a result of complex interactions between climate, terrain, soil, water availability, and various human activities. Different land use spatial patterns have different geographic causative mechanisms, and the ecological functions and their spatial graphics also vary. The key problem of this study is the quantiative representation of different land use patches, and description of actual patches with graphics. In this article, landscape ecology and geographical graphic information theory are used to discuss this problem by taking Qianguo county of Jilin province in Northeast China as a case. Based on studies of numerous land use patches, we discuss the quantitative description and graphic presentation method of patch shapes of various principal land use types,obtain characteristic graphics of different land use ty pes and law of spatial distribution.The results indicate that the interior rate of residential patch is the lowest, which decreases with the increase of patch area at the scale of 0 1km², while grassland is the highest which increases with the increase of area. The form index of residential patch and grassland changes slightly with patch area, and forest increases with patch area.The fractal dimension of grassland is high and increases with the patch area, while residential patch patch changes a little. The circularity of residential patch remains unchanged with the patch area changes. The patch shape of forest is mostly similar to rectangleas the patch area is less than 0.1 km². The grassland patches shape as rectangle with curvatures at the edges.The patch shape of water area is similar to ellipse. The shapes of residential patch and farmland are simple, and farmland presents as echelon composed by several rectangles when the area is larger than 1km². These two land-use types are reflected intensively by human activities and the patch shapes often have right angles. The other patch shapes are irregular graphics with curvatures at the edges. The result of VCM analysis shows patches of forest are scatteredly distributed with patch distance mostly exceeding 2000 m. The patch distance of grassland is small, mostly less than 1000 m as patches are mostly distributed in concentration. Almost all residential patches are distributed regularly with patch intervals of 3000 m. This study provides basis for further analysis of the geographic causative mechanism and ecological function of different land use spatial patterns.