【摘要】 植被覆盖在维持生态系统结构稳定和防治水土流失等方面发挥着重要的作用，海南自1988年建省以来迅速发展，导致海南岛植被覆盖也产生了巨大的变化。为揭示海南本岛地形因子对植被覆盖度的影响以及为海南本岛进一步制定合理的生态环保策略提供依据，基于1988、1998、2008、2017和2020年Landsat-TM/OLI多光谱影像，以海南本岛为研究区域，采用归一化植被指数和像元二分模型进行植被覆盖度提取，通过线性趋势分析海南本岛近30 a植被覆盖变化特征。并结合30 m＿DEM获取的海、坡度和坡向数据，来进一步探讨海南本岛植被覆盖度在不同地形因子条件下的空间分布特征。结果表明：(1)1988～2020年海南岛平均植被覆盖度介于0.58～0.88之间，整体呈先下降后上升趋势；(2)海南岛高植被覆盖主要分布于海南岛中部、西南部和东南部地区，低植被覆盖主要出现在居住区、沿海地区等人为干扰因素较高的地区；(3)海南岛各等级植被覆盖均随海拔的增加而不断降低，在海拔小于100 m的区域分布面积最大；坡度为0～5°时植被覆盖面积达到最大值，随着坡度的增加，植被覆盖面积呈减少趋势；各等级植被覆盖在阴坡和阳坡的分布面积变化差异不大，主要以高植被覆盖类型为主。更多还原

【Abstract】 Vegetation cover plays an important role in maintaining the stability of the ecosystem and preventing the loss of water and soil. Hainan has developed in a rapid pace since its establishment as a province in 1988, which has led to tremendous changes in the vegetation cover across the Hainan Island. To shed light on the impact of topographic factors on the vegetation cover on the Hainan Island and provide a basis for a more reasonable ecological and environmental protection strategy for the island, this study targets the Hainan Island for research, and applies the normalized differential vegetation index and the dimidiate pixel model for the vegetation cover extraction based on the Landsat TM/OLI multispectral images of 1988, 1998, 2008 2017 and 2020, and provides a linear trend analysis in the characteristics of the vegetation cover changes on the Hainan Island in the last 30 years. Combined with the altitude, slope and aspect data obtained through 30m＿DEM, it offers further explorations over the characteristics of the spatial distribution of vegetation cover on the Hainan Island with different topographic factors. The results show that:(1) The average vegetation cover on the Hainan Island from 1988 to 2020 is between 0.58～0.88, and the general trend is first downward and then upward;(2) High vegetation cover is mainly distributed in the central, southwestern and southeastern parts of the Hainan Island, while low vegetation cover mainly appears in areas of the island with man-made interference such as residential and coastal areas.(3) With the increase of altitude, the vegetation cover of various levels in the Hainan Island decreases, and the areas with an altitude of less than 100 meters have the largest vegetation cover; at 0～5° of the slope, the vegetation cover reaches the maximum, and with the increase of slope, the vegetation cover shrinks; and there is little difference in the vegetation cover between the shady and sunny slopes that are primarily characterized by high vegetation cover.更多还原