中文摘要：

因为人的活动的影响，在中国的沿海的躲蔽处森林在破坏和降级的威胁下面。对沿海的防风林的保护效率评价是躲蔽处森林补习计划和持续管理的一个重要部件。在这研究，一个保护效率索引(PEI ) 模型用设计追求方法被建立在 Dongshan 岛的沿海的节规模估计沿海的躲蔽处森林的保护的质量，中国。三个标准被使用，包括森林看台结构，森林带结构，和防风林效果；每个标准进一步包括了多重因素。在 Dongshan 岛的沿海的躲蔽处森林里基于 31 个阴谋的调查数据，我们用一个追求模型的设计计算了 PEI 值。结果显示出 64.5 ? PEI 的 % 掉落了在或在中间的水平下面，它能显示沿海的防风林的地位是不能令人满意的。为了进一步探索不同海湾和陆地使用类型是否在 PEI 和评估创造重要差别，索引，我们使用了 ANOVA 在沿海的防风林上测试各种各样的海湾的影响和陆地使用的形式。结果显示出那 PEI，大多数这些索引由海湾显著地不同；吝啬的树高度，吝啬的 DBH，吝啬的王冠宽度，看台密度，植被范围，和风速度减小由陆路显著地不同使用。因此，为不同地点，海湾和包围陆地使用的相关措施能被建议改进沿海的防风林的存在条件。这研究的结果在 Dongshan 岛上为未来变化和沿海的防风林的持续管理提供一个理论、技术的框架。

英文摘要：

The coastal shelter forest in China is under threat of destruction and degradation because of the impact of human activities. Protection efficiency assessment of the coastal shelterbelt is an important component of shelterforest remediation planning and sustainable management. In this study, a protection efficiency index （PEI） model was established using the projection pursuit method to assess the protective quality of the coastal shelter forest at the coastal section scale of Dongshan Island, China. Three criteria were used, including forest stand structure, forest belt structure, and windbreak effect; each criterion further comprised multiple factors. Based on survey data of 31 plots in the coastal shelter forest of Dongshan Island, we calculated PEI values using a projection of a pursuit model. The result showed 64.5 % of the PEIs fell at or below the middle level, which can indicate the status of the coastal shelterbelt is unsatisfactory. To further explore whether the different bays and land use types create significant differences in PEIs and evaluation indices, we used an ANOVA to test the influence of various bays and forms of land use on coastal shelterbelts. The results showed that PEI and most of the indices differed significantly by bay; mean tree height, mean DBH, mean crown width, stand density, vegetation coverage, and wind velocity reduction differed significantly by land use. Therefore, relevant measures for different locations, bays and surrounding land use can be proposed to improve the existing conditions of the coastal shelterbelt. The results of this study provide a theoretical and technical framework for future changes and sustainable management of coastal shelterbelt on Dongshan Island.