样线法在北方基岩性海岛植被调查中的应用效果评价 ——以北长山岛为例

植被是海岛生态系统的重要组成部分。由于海岛陆地环境与大陆的差异性，现有的陆域植被调查方法不能完全适用于海岛植被。亟须结合现有成熟的陆地植被调查方法，选取不同类型的海岛，对调查方法中的关键环节进行实地测试，积累数据进行统计分析，以得到适用于海岛特殊地理环境海岛植被调查技术方法。文章针对植被调查中的样线法，以北长山岛两种不同面积的调查区域为例，对比分析不同样线设置方法，明确在该岛屿何种坡向、坡位，何种类型植物群落中设置样线，以及设置多长的样线才能够较为完整地代表该调查区域的植物物种丰富度，同时降低大量的调查时间，最终确定最优的海岛样线设置原则，为海岛植被群落调查中样线的有效选择提供科学依据。

Evaluation of Line Transect Sampling Method in Vegetation Survey of North Rock Island: take North Changshan Island for example

Vegetation is an important part of island ecosystem.Due to the distinction of vegetation from mainland vegetation,the existing mainland sampling method cannot be entirely applied to the islands.Hence it is necessary to combine the existing mainland vegetation sampling methods,to select different types of islands to test the key links of the methods,and to accumulate data for statistical analysis,so as to obtain the technical methods suitable for island vegetation sampling.Aiming at the application of Line Transect Method in island vegetation survey,this paper chose two different survey areas of North Changshan Island as examples,compared different sample line setting methods,clarified how to set the sampling line in different kind of slope direction,slope position,and types of plant communities,and how long the sampling line could be set in order to represent the island more completely.Finally,the optimal principle of setting up the island sample line was determined,which provided scientific basis for the effective selection of the sample line in the investigation of island vegetation community.