景观指数是定量分析景观格局的一种常用手段，但目前大部分景观指数，往往只侧重于对景观斑块或格局的几何特征进行简单分析和描述，忽略了景观格局动态变化过程的信息，缺乏将景观空间分布格局与其变化过程相结合的深入研究。作者提出了一种新的景观指数—景观扩张指数 (Landscape Expansion Index, LEI)，与传统的景观指数相比，LEI包涵了景观格局的过程信息，可用来分析两个或多个时相景观格局的动态变化，而传统景观指数则只能反映某一时相景观格局的信息。将景观扩张指数应用于东莞市1988-2006年期间的城市景观扩张过程中，研究结果表明，LEI能够很好的识别城市扩张的三种类型—填充式、边缘式以及飞地式。此外，通过对东莞市城市扩张过程LEI的变化分析，发现东莞市城市扩张规律与城市增长相位理论是相符合的。

Landscape index is an instrument commonly used for quantitative analysis of landscape pattern. However, most of landscape indices are generally focused on simple analysis and description of the geometric features of a landscape patch or pattern, while neglecting information on dynamic changes of landscape pattern. In this paper a new landscape index, i.e., landscape expansion index (LEI), is proposed. In contrast with conventional landscape indices, LEI contains information of the formation processes of landscape pattern, so it can be used to analyze the dynamic changes of two or more temporal phases of landscape pattern, since conventional landscape indices only reflect information for one certain temporal phase of landscape pattern. Landscape expansion index was applied to studies on the urban landscape expansion of Dongguan City, Guangdong, China for the period of 1988-2006, and the results indicate that LEI can perfectly identify the three types of urban expansion, i.e., infilling type, edge-expansion type and outlying type. Additionally, based on an analysis of the LEI changes in the urban expansion processes of Dongguan City, it was found that the rule governing urban expansion of Dongguan City is consistent with the phases theory on urban growth. This study further demonstrates that LEI can be used effectively for a quantitative analysis of the dynamic changes of landscape pattern, and LEI proves to be significant to the studies on landscape pattern and its dynamic changes.