Bertness Mark D, Ewanchuk Patrick J, Silliman Brian Reed
Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA.
Proc Natl Acad Sci U S A. 2002 Feb 5;99(3):1395-8. doi: 10.1073/pnas.022447299. Epub 2002 Jan 29.
Salt marshes play a critical role in the ecology and geology of wave-protected shorelines in the Western Atlantic, but as many as 80% of the marshes that once occurred in New England have already been lost to human development. Here we present data that suggest that the remaining salt marshes in southern New England are being rapidly degraded by shoreline development and eutrophication. On the seaward border of these marshes, nitrogen eutrophication stimulated by local shoreline development is shifting the competitive balance among marsh plants by releasing plants from nutrient competition. This shift is leading to the displacement of natural high marsh plants by low marsh cordgrass. On the terrestrial border of these same marshes, shoreline development is also precipitating the invasion of the common reed, Phragmites, by means of nitrogen eutrophication caused by the removal of the woody vegetation buffer between terrestrial and salt marsh communities. As a consequence of these human impacts, traditional salt marsh plant communities and the plants and animals that are dependent on these habitats are being displaced by monocultures of weedy species.
盐沼在西大西洋受海浪保护的海岸线的生态和地质方面发挥着关键作用，但新英格兰曾经存在的盐沼中多达80%已因人类开发而消失。在此，我们展示的数据表明，新英格兰南部剩余的盐沼正因海岸线开发和富营养化而迅速退化。在这些盐沼的向海边界，局部海岸线开发引发的氮富营养化通过使植物摆脱养分竞争，正在改变盐沼植物之间的竞争平衡。这种转变正导致天然的高沼植物被低沼的互花米草取代。在这些相同盐沼的陆地边界，海岸线开发也因陆地和盐沼群落之间木质植被缓冲带的移除导致氮富营养化，从而促使芦苇入侵。由于这些人类影响，传统的盐沼植物群落以及依赖这些栖息地的动植物正被杂草物种的单一栽培所取代。
