Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland 7602, South Africa.
Proc Natl Acad Sci U S A. 2012 Mar 27;109(13):4938-43. doi: 10.1073/pnas.1119787109. Epub 2012 Mar 5.
Invasive alien species are among the primary causes of biodiversity change globally, with the risks thereof broadly understood for most regions of the world. They are similarly thought to be among the most significant conservation threats to Antarctica, especially as climate change proceeds in the region. However, no comprehensive, continent-wide evaluation of the risks to Antarctica posed by such species has been undertaken. Here we do so by sampling, identifying, and mapping the vascular plant propagules carried by all categories of visitors to Antarctica during the International Polar Year's first season (2007-2008) and assessing propagule establishment likelihood based on their identity and origins and on spatial variation in Antarctica's climate. For an evaluation of the situation in 2100, we use modeled climates based on the Intergovernmental Panel on Climate Change's Special Report on Emissions Scenarios Scenario A1B [Nakićenović N, Swart R, eds (2000) Special Report on Emissions Scenarios: A Special Report of Working Group III of the Intergovernmental Panel on Climate Change (Cambridge University Press, Cambridge, UK)]. Visitors carrying seeds average 9.5 seeds per person, although as vectors, scientists carry greater propagule loads than tourists. Annual tourist numbers (∼33,054) are higher than those of scientists (∼7,085), thus tempering these differences in propagule load. Alien species establishment is currently most likely for the Western Antarctic Peninsula. Recent founder populations of several alien species in this area corroborate these findings. With climate change, risks will grow in the Antarctic Peninsula, Ross Sea, and East Antarctic coastal regions. Our evidence-based assessment demonstrates which parts of Antarctica are at growing risk from alien species that may become invasive and provides the means to mitigate this threat now and into the future as the continent's climate changes.
入侵的外来物种是全球生物多样性变化的主要原因之一，世界上大多数地区都广泛认识到了它们的风险。同样，人们认为它们是对南极洲最重要的保护威胁之一，尤其是随着该地区气候变化的进行。然而，尚未对这些物种对南极洲构成的风险进行全面的、全大陆范围的评估。在这里，我们通过在国际极地年的第一个季节（2007-2008 年）期间对所有类别访问南极洲的人员所携带的维管植物繁殖体进行采样、鉴定和绘图，并根据其身份和来源以及南极洲气候的空间变化评估繁殖体建立的可能性，来对南极洲所面临的风险进行全面的评估。为了评估 2100 年的情况，我们使用基于政府间气候变化专门委员会的特别报告排放情景 A1B 模型化的气候[Nakićenović N，Swart R，eds（2000）特别报告排放情景：政府间气候变化专门委员会工作组 III 的特别报告（剑桥大学出版社，英国剑桥）]。携带种子的访客平均每人携带 9.5 颗种子，尽管作为传播者，科学家携带的繁殖体负荷比游客大。每年的游客人数（约 33,054 人）高于科学家（约 7,085 人），因此这些繁殖体负荷的差异有所缓和。外来物种的建立目前最有可能在西南极半岛。该地区最近发现的几种外来物种的原始种群证实了这些发现。随着气候变化，南极半岛、罗斯海和东南极沿海地区的风险将会增加。我们基于证据的评估表明，南极洲的哪些地区正面临着外来物种入侵的风险不断增加，这些外来物种可能会成为入侵物种，并为现在和未来随着大陆气候的变化而减轻这一威胁提供了手段。
