区域生态系统景观结构演化定量评价方法

A methodological researches on quantitative assessment for the dynamic trends of landscape structure in regional ecosystems

为了在更宏观层次上评价人类活动对区域生态系统景观格局的影响 ,设计了一种三角图方法。根据自然景观指数、半自然半人工景观指数和人工景观指数的相对比例及其变化 ,该方法把区域生态系统分为 4种景观结构类型以及 6种变化趋势 ,即自然型景观、半自然半人工型景观、人工型景观和混合型景观 ,自然化 -人工化趋势、自然化趋势、自然化 -半自然半人工化趋势、半自然半人工化趋势、半自然半人工化 -人工化趋势和人工化趋势 ,这些景观结构类型和变化趋势分别对应于三角图中的不同区域和演化方向。青岛城阳区、深圳龙华区及海口市的应用实例表明 ,该方法原理简单 ,计算简便 ,结果直观 。

A novel Triangle Methodology was designed to macroscopically assess the effects of human acuities on landscape pattern. Based on the intensity of anthropogenic effects, regional landscape was identified as three categories: a natural landscape, a half-natural half-artificial landscape, and an artificial landscape. The status and dynamic trends of landscape structure were then evaluated by examining the interrelationships among three aggregate landscape indices: a natural landscape index (NLI), a half-natural half-artificial landscape index (HNALI), and an artificial landscape index (ALI). The three elements were then combined within a triangular framework to show the basic visual representation and interconnectivity of three indices. Each axis is read in an anticlockwise direction from zero to 100%. Further, each of the axes is equally divided into four segments or ranges as: 0～25%, 25%～50%, 50%～75%, and 755%～100% allowing the diagram to illustrate relative percentage combinations of the three aggregate landscape indices ALI, NLI and HNALI. In addition, the triangle is further sub-divided into four areas A、B、C, and D expressing four types of landscape structure: nature-type landscape, half-natural half-artificial type landscape, artificial type landscape, and mixed landscape. Within any one triangle, there are six possible trends in movement according to the relative percentage changes in the three aggregate indexes: naturalization-artificialization trend, naturalization trend, naturalization-half-naturalization half-artificialization trend, half-naturalization half-artificialization trend, half-naturalization half-artificialization-artificialization trend, and artificialization trend. Depending on the relative position of data points associated with alternative data sets, the corresponding the status and dynamic trends in landscape structure can then be determined. The assessment results from the Cheng-Yang region in Qing-Dao City and Long-Hua region in Shen-Zhen City as well as from Hai-Kou City suggest that the Triangle Methodology is a valuable uncomplicated tool with ease of calculation and intuitional results. It could be widely used for quantitatively assessing the effects of human acuities on regional landscape patterns.