Lee Jennifer E, Chown Steven L
Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
Ecol Appl. 2009 Oct;19(7):1944-59. doi: 10.1890/08-2157.1.
Globalization has resulted in unprecedented movements of people, goods, and alien species across the planet. Although the impacts of biological invasions are widely appreciated, a bias exists in research effort to post-dispersal processes because of the difficulties of measuring propagule pressure. The Antarctic provides an ideal model system in which to investigate propagule movements because of the region's isolation and small number of entry routes. Here we investigated the logistics operations of the South African National Antarctic Programme (SANAP) and quantified the initial dispersal of alien species into the region. We found that over 1400 seeds from 99 taxa are transported into the Antarctic each field season in association with SANAP passenger luggage and cargo. The first ever assessment of propagule drop-off indicated that 30-50% of these propagules will enter the recipient environment. Many of the taxa include cosmopolitan weeds and known aliens in the Antarctic, indicating that logistics operations form part of a globally self-perpetuating cycle moving alien species between areas of human disturbance. In addition, propagules of some taxa native to the Antarctic region were also found, suggesting that human movements may be facilitating intra-regional homogenization. Several relatively simple changes in biosecurity policy that could significantly reduce the threat of introduction of nonnative species are suggested.
全球化导致了人员、货物和外来物种在全球范围内前所未有的流动。尽管生物入侵的影响已广为人知,但由于测量繁殖体压力存在困难,研究工作存在偏向于扩散后过程的倾向。南极地区因其隔离性和少量的进入途径,为研究繁殖体移动提供了一个理想的模型系统。在此,我们调查了南非国家南极计划(SANAP)的后勤运作,并量化了外来物种进入该地区的初始扩散情况。我们发现,在每个野外季节,超过1400粒来自99个分类群的种子随SANAP的乘客行李和货物被运进南极。首次对繁殖体投放的评估表明,其中30% - 50%的繁殖体将进入接收环境。许多分类群包括世界性杂草以及南极已知的外来物种,这表明后勤运作构成了一个全球自我延续的循环的一部分,在外来物种在人类干扰区域之间转移。此外,还发现了一些南极地区本土分类群的繁殖体,这表明人类活动可能在促进区域内同质化。文中提出了一些生物安全政策方面相对简单的改变,这些改变可以显著降低引入非本土物种的威胁。