多维地形因子作用下的西南山地丘陵过渡带景观格局研究:以涪江流域中上游为例

    Study on the Landscape Pattern of Southwest Transition Zone From Mountainous to Hilly Areas Under the Influence of Multi-Dimensional Terrain Factors: A Case Study of the Middle and Upper Reaches of Fujiang River Basin

    • 摘要: 山地丘陵过渡带地形独特,地形因子分析不仅可以对复杂地理单元的景观格局做出合理解释,而且能进一步了解景观格局分布规律,为优化空间配置奠定基础。以2017年Google Earth影像、DEM和全球30 m地表覆盖数据为数据源,运用GIS技术、分布指数、景观格局指数和移动窗口法等方法,分析了涪江流域中上游地区景观类型随高程、坡度、起伏度和坡向的空间分布特征,利用Pearson相关性分析探究不同地形因子对景观格局变化的影响程度。结果表明:(1)随着高程、坡度和起伏度的增加,景观类型由人为主导的耕地、建设用地过渡为以自然为主导的林地、草地;从阳坡到阴坡,建设用地分布由优势到劣势下降最为明显。(2)流域景观类型最为丰富的地貌为冲积平原,主要分布于海拔> 500~650 m、坡度0~5°和起伏度> 10~30 m的区域;高海拔、坡度和起伏度地区的景观格局单一化趋势明显,破碎化程度较轻。(3)山地区的多样化景观主要分布在涪江沿岸,丘陵区涪江沿岸景观呈现单一化趋势,冲积平原区景观由外向内呈现出相对单一化-多样化-相对单一化的趋势,城乡结合部景观最为丰富。(4)不同地形因子对景观格局的影响程度为高程>坡度>起伏度>坡向,高程、坡度、起伏度与景观格局有较强的相关性,而坡向则表现为弱相关性。

       

      Abstract: Due to its unique topography, the mountainous and hilly transition zone has a complex but regular landscape pattern. The analysis of terrain factors can not only make a reasonable explanation for the landscape pattern of complex geographical units, but also help further understand the distribution law of landscape pattern, laying a foundation for optimizing spatial allocation. Mainly based on Google Earth image, DEM and 30 m global surface coverage data in 2017 as data sources, applying methods of GIS technology, distribution index, landscape pattern index and moving window, this paper analyzes the spatial distribution characteristics of landscape types in the middle and upper reaches of Fujiang River Basin with the changes of elevation, slope, fluctuation and slope direction, the spatial difference of landscape pattern with the moving window method as well as exploring the influence degree of different terrain factors on landscape pattern change with Pearson correlation analysis method. The results show that: (1) With the increase of elevation, slope and fluctuation, the landscape type changes from man-made culticated and construction land to nature-driven grass and forest land; it is with the most obvious advantage and disadvantage changes of the construction land from sunny slope. (2) The most abundant landscape type in the basin is the impact plain, which is mainly distributed in the areas with altitude (>500-650 m), slope (0-5°) and fluctuation (>10-30 m); while the landscape pattern tends to be single and the fragmentation degree is weak in the areas with high altitude, slope and fluctuation. (3) The diversified landscape in mountainous areas is mainly distributed along the Fujiang River, while the landscape in hilly areas tends to be unitary along the Fujiang River. The landscape in the impact plain areas tends to be relatively unitary → diversified → relatively unitary from the outside to the inside, and the landscape in the urban-rural junctions is the most abundant. (4) The influence degree of different terrain factors on landscape pattern can be expressed as: elevation > slope > fluctuation > slope direction. Elevation, slope and fluctuation have strong correlation with landscape pattern, while slope direction shows weak correlation.

       

    /

    返回文章
    返回