A Half-Century of Change in Arctic Alaskan Shrubs: A Photographic-Based Assessment

该项目将对大约50年前拍摄的同一地形进行航拍，以检查环境的变化，特别是以灌木为主的地区的扩张情况。灌木的大小、密度和范围将会与旧照片和新照片进行比较，以确定先前试点研究的结果是否适用于北坡更广泛的地区。灌木向北扩张是对气候变暖的一种预期响应，对全球变暖最先影响地区的全球变化研究具有重要意义。实地测量的植被指数（如植被年龄、大小、尺寸、组成、间距、生长率）将与气温历史进行比较，以评估气候变暖对该地区灌木生长/扩张的影响。

The project will take aerial photographs of the same terrain photographed approximately 50 years previously to examine changes in the environment, particularly the expansion of areas dominated by shrubs. Shrub size, density, and extent will be compared between the old scenes and the new photographs to see if previous results from a pilot study are applicable to a wider area of the North Slope. The northward expansion of shrubs is an expected response to climate warming and will have important implications for global change research in an area expected to experience the first impacts from global warming. On-site measurements of vegetation indices (e.g. vegetation age, size, dimensions, composition, spacing, growth rates) will be used in comparison with temperature history to assess the impacts of warming climate on shrub growth/expansion in the region.