流域尺度土地利用与土壤类型空间分布的相关性研究

随着人类活动日益加强，土地利用变化及其驱动力研究已经成为国际地理学界研究的热点。但目前更多的工作侧重于研究人为因子，如人口增长、政策变化等因子对土地利用变化的影响，其实土地利用在宏观尺度上的变化一定程度上取决于自然环境背景，因此研究土地利用变化的自然环境背景特征对于进一步探讨土地利用变化的自然驱动力具有重要意义。土壤类型的空间分布在一定程度将影响土地利用的空间分布格局和变化过程。本文利用遥感、地理信息系统，通过选取景观格局指标，以于桥水库流域为例，研究了土地利用与土壤类型空间分布之间的相互关系。结果表明：(1)受人类活动干扰较弱的土地利用类型，如有林地、稀疏林地、灌木林地、其他林地和草地，主要分布在淋溶褐土、褐土性土以及棕壤地区；而与人类活动密切的土地利用类型，如山区旱耕地、丘陵区水田、丘陵区旱耕地和平原区旱耕地主要分布在淋溶褐土、褐土性土和潮土地区；(2)同类地区土地利用的多样性指数要比土壤的低。并且土地利用和土壤类型多样性均表现出明显的地形梯度效应，从中低山区、低山丘陵区、丘陵平原区到山间盆地区，土壤多样性指数从小到大有规律地变化。而土地利用类型多样性变化较为复杂，反映出人类活动对土地利用格局的影响较强，而对土壤类型的影响相对较小；(3)随着平均斑块面积的增加，流域多样性指数将呈下降趋势。土地利用多样性指数与流域总面积之间的相关性较差，但土壤多样性指数与流域总面积表现出的相关性较好；(4)土地利用类型与土壤类型之间，平均斑块面积上没有明显的相关关系，但在多样性指数之间存在着较好的相关性。土壤类型丰富多样的地区，土地利用的多样性指数也相对较高。

Correlation analysis on spatial pattern of land use and soil at catchment scale

Land use/cover change and its driving force have become the hot topic of ecologists and geographers within recent years with farmland loss due to population growth. However, most research works carried out at present are focused on the role of human factors on land use/land cover change, for example population growth, grain demand, road construction, urban expansion, policy change and others. In fact, apart from the human factors, the land use/land cover change on macro scale is more dependent on the natural environmental background. As one of principal environmental factors, the spatial distribution of soil types may affect land use structure and change . To study the relationship between soil and land use pattern will be of significance to identify the effect of natural environmental factors on land use change . In this study, a case study was carried out in Yuqiao Reservoir Basin focusing on the relationship between the soil spatial pattern and land use pattern by using remote sensing data, GIS modeling, and landscape ecological approaches. It was found: (1) the land use types less involved by human, such as woodland (including woodland, sparse woodland, shrubland, other types) and grassland, are mainly distributed in the leaching Cinnamon soil, infant cinnamon soil and brown forest soil while the land use types affected strongly by human activity, such as cropland, are mainly distributed in the leaching Cinnamon soil, infant cinnamon soil and fluvoaquic soil; (2) The land use diversity is commonly smaller than soil diversity in the same area. Meanwhile, land use and soil diversity index changes with the topographic gradient. They increase from mid-low hill areas, low-hill areas, low-hill and plain areas to flat basin inter-hills; (3) Both the diversity index of soil and land use decline with the mean patch area increase, and the soil diversity increase with the total area increase of the catchment rather than the land use diversity index; (4) Comparing the soil and the land use, slight correlationship is found between the mean patch size of land use and soil, while a good positive relationship is found between them. This implies that diverse land use areas often appear in the heterogeneous soil areas.