关键词: PSAS, 赤潮生物, 正交试验, 絮凝作用

Abstract: Based on the 1∶10000 topographic map of Jiangsu Province in 2000, and by the method of neighborhood statistics, this paper analyzed the spatial distribution characteristics of road density (RD) and settlement percentage coverage (SPC) in 15 counties of Jiangsu Province at the scales of 5, 10, 15, and 20 km, with the correlation degrees of RD and SPC at 16 scale pairs of each county compared. The results showed that road was a kind of the landscape element with low heterogeneity, while settlement was a kind of the landscape element with high heterogeneity. The spatial heterogeneity of road and settlement all decreased with increasing scale, but the decreased degree of the spatial heterogeneity of road was less obvious than that of the spatial heterogeneity of settlement. In the areas with higher RD or SPC, the spatial heterogeneity of road and settlement tended to be lower. At the 16 scale pairs, the correlation degree of RD at 20km scale and of SPC at 5km scale was the highest, and the RD at 20km scale showed a ladder-like growth with the increase of SPC at 5km scale, presenting a discontinuous growth. Due to the differences in the scaledependent attributes between RD and SPC, it would be necessary to compare the correlation degrees of these two elements under different scale-pairs, and select the appropriate scale combinations to study the correlations between landscape elements under different scale-pairs.