Oxford University Centre for the Environment, Long-Term Ecology Laboratory, South Parks Road, Oxford OX1 3Q Y, United Kingdom.
Ecology. 2011 Apr;92(4):805-12. doi: 10.1890/10-1290.1.
The Galápagos Islands are globally renowned for their ecological value and as a world symbol of scientific discovery; however the native biodiversity of this unique region is currently under threat. One of the primary concerns is the detrimental impact of approximately 750 nonnative plants introduced over the last 500 years of human presence in the archipelago. In addition to these known introduced species, there are an additional 62 vascular plants classified as "doubtful natives," where native status remains unclear. To help address the questions of provenance regarding these doubtfully native species and their impact on highland ecosystems over the past 500-1000 years, we analyzed plant macrofossils in sedimentary records. Appropriate species classification (native or introduced) was determined using baseline data of species presence on the islands. We confirmed that six plants (Ageratum conyzoides, Solanum americanum, Ranunculus flagelliformis, Brickellia diffusa, Galium canescens, and Anthephora hermaphrodita) once considered doubtful natives or introduced are actually native to the Galápagos flora. These results have relevance not just for the Galápagos but also many other oceanic islands in demonstrating the application of palaeobotanical data to conserving and restoring native biodiversity.
加拉帕戈斯群岛以其生态价值和世界科学发现的象征而闻名于世；然而，这个独特地区的本地生物多样性目前正受到威胁。其中一个主要问题是在人类存在于该群岛的过去 500 年中引入的约 750 种非本地植物的不利影响。除了这些已知的外来物种，还有另外 62 种维管植物被归类为“可疑本地种”，其本地地位仍不清楚。为了帮助解决这些可疑本地种的起源问题及其在过去 500-1000 年对高地生态系统的影响，我们分析了沉积物记录中的植物宏观化石。使用岛屿上物种存在的基线数据确定了适当的物种分类（本地或引入）。我们证实，有六种植物（Ageratum conyzoides、Solanum americanum、Ranunculus flagelliformis、Brickellia diffusa、Galium canescens 和 Anthephora hermaphrodita）曾经被认为是可疑的本地种或引入种，实际上是加拉帕戈斯植物区系的本地种。这些结果不仅对加拉帕戈斯群岛，而且对许多其他海洋岛屿都具有重要意义，证明了古植物学数据在保护和恢复本地生物多样性方面的应用。
