贵州典型坝子土地利用强度空间演变及景观格局响应

基于坝子(喀斯特山区受人类活动影响最明显的特殊地貌)尺度较小的特征,运用系统网格法,结合半方差变异函数修正模型,分析贵州省境内3种类型共15个坝子2005、2010、2015年土地利用强度的空间演变特征,揭示贵州岩溶山区典型坝子土地利用强度空间演变的一般规律及其与坝子内部景观格局变化的相互关系.结果表明: 贵州坝子土地利用强度空间动态演变和景观格局响应模式展现出明显的类型差异.总体上,土地利用强度随坝子经济水平由高到低呈梯度递减.微观演变上,市县中心坝子的土地利用强度围绕坝地中心外围呈同心带状先减后增,空间演变趋势为稳定-扩张型;市县周围坝子的土地利用强度以单一“极-轴”为高强度中心,变化兼具增减,演变趋势为波动型;偏远地区坝子的土地利用强度基本稳定不变,甚至小幅减弱,演变趋势为稳定-衰弱型;坝子景观格局与土地利用强度变化因坝区主导功能差异存在5种不同的响应关系模式.研究期间,3种类型坝子土地利用强度的空间演变受自然和人文因子双重控制,各因子之间相互作用形成其空间演变的典型特征.

Spatial evolution of land use intensity and landscape pattern response of the typical basins in Guizhou Province,China

Based on the small scale characteristics of the basin, which is a kind of special landform influenced by the human activities obviously in Karst mountain area, the system grid method and the semivariogram model were used to analyze the 15 basins which belonged to three types in the territory of Guizhou Province to reveal the general pattern of spatial evolution of land use intensity and the mutual relationship with the landscape pattern change of the typical basins in the Karst mountainous area of Guizhou Province in 2005, 2010 and 2015. The results showed that the dynamic spatial evolution of land use intensity and response mode of landscape pattern showed obvious difference under the different basin types. In general, with the decrease of economic level of the basins from high to low, the land use intensity decreased in the form of a gradient. At the level of microcosmic evolution, the land use intensity of basins in the center of the cities and counties descended first and then ascended in the form of concentric band around the periphery of the center in the basin, and the spatial evolution trend of this kind of basin exhibited a stable and expanded form. The land use intensity of basins surrounding cities and towns, with a high intensity center, that could either increase or decrease, exhibited a fluctuating spatial evolution trend. The land use intensity of remote basins was basically stable, even slightly weakened and its space evolution was stable and debilitating. Because of the divergence of dominant function of the basins, there were five different modes of response between the change of land use intensity and landscape pattern of basins. During the study period, the spatial evolution of land use intensity of these 3 basin types was driven by natural and human factors. The interaction among various factors formed the typical characteristics of the land use intensity spatial evolution type of different basins.