Ecol Appl. 2014 Apr;24(3):484-502. doi: 10.1890/13-0905.1.
Many protected areas may not be adequately safeguarding biodiversity from human activities on surrounding lands and global change. The magnitude of such change agents and the sensitivity of ecosystems to these agents vary among protected areas. Thus, there is a need to assess vulnerability across networks of protected areas to determine those most at risk and to lay the basis for developing effective adaptation strategies. We conducted an assessment of exposure of U.S. National Parks to climate and land use change and consequences for vegetation communities. We first defined park protected-area centered ecosystems (PACEs) based on ecological principles. We then drew on existing land use, invasive species, climate, and biome data sets and models to quantify exposure of PACEs from 1900 through 2100. Most PACEs experienced substantial change over the 20th century (> 740% average increase in housing density since 1940, 13% of vascular plants are presently nonnative, temperature increase of 1 degree C/100 yr since 1895 in 80% of PACEs), and projections suggest that many of these trends will continue at similar or increasingly greater rates (255% increase in housing density by 2100, temperature increase of 2.5 degrees-4.5 degrees C/100 yr, 30% of PACE areas may lose their current biomes by 2030). In the coming century, housing densities are projected to increase in PACEs at about 82% of the rate of since 1940. The rate of climate warming in the coming century is projected to be 2.5-5.8 times higher than that measured in the past century. Underlying these averages, exposure of individual park PACEs to change agents differ in important ways. For example, parks such as Great Smoky Mountains exhibit high land use and low climate exposure, others such as Great Sand Dunes exhibit low land use and high climate exposure, and a few such as Point Reyes exhibit high exposure on both axes. The cumulative and synergistic effects of such changes in land use, invasives, and climate are expected to dramatically impact ecosystem function and biodiversity in national parks. These results are foundational to developing effective adaptation strategies and suggest policies to better safeguard parks under broad-scale environmental change.
许多保护区可能无法充分保护周围土地上的生物多样性和全球变化。这些变化因素的规模以及生态系统对这些因素的敏感性在不同的保护区之间存在差异。因此，有必要评估保护区网络的脆弱性，以确定最脆弱的保护区，并为制定有效的适应战略奠定基础。我们对美国国家公园受到气候和土地利用变化的影响以及对植被群落的后果进行了评估。我们首先根据生态原则定义了以公园为中心的保护区生态系统（PACEs）。然后，我们利用现有的土地利用、入侵物种、气候和生物群落数据集和模型，量化了 1900 年至 2100 年 PACEs 的暴露情况。大多数 PACEs 在 20 世纪经历了巨大的变化（自 1940 年以来，住房密度平均增加了 740%，目前有 13%的维管植物是非本地的，80%的 PACEs 自 1895 年以来温度每 100 年上升 1 摄氏度），预测表明，这些趋势中的许多将以类似或更高的速度继续（到 2100 年，住房密度将增加 255%，温度每 100 年上升 2.5 到 4.5 摄氏度，到 2030 年，30%的 PACE 地区可能会失去当前的生物群落）。在未来的一个世纪里，预计 PACEs 的住房密度将以自 1940 年以来的 82%的速度增长。未来一个世纪的气候变暖速度预计将是过去一个世纪的 2.5-5.8 倍。在这些平均值的基础上，个别公园 PACE 对变化因素的暴露程度在重要方面有所不同。例如，大烟山等公园土地利用程度高，气候暴露程度低，大沙丘等公园土地利用程度低，气候暴露程度高，而雷耶斯角等少数公园则在两个轴上都有很高的暴露程度。土地利用、入侵物种和气候的这些变化的累积和协同效应预计将对国家公园的生态系统功能和生物多样性产生巨大影响。这些结果是制定有效适应战略的基础，并为在广泛的环境变化下更好地保护公园提供了政策建议。
