Global Ecological Change (GEC) Laboratory, School of Environmental Sciences, University of Guelph, Guelph, ON, Canada.
Oecologia. 2010 Dec;164(4):1095-106. doi: 10.1007/s00442-010-1769-z. Epub 2010 Sep 22.
Climate change is expected to promote migration of species. In ecotones, areas of ecological tension, disturbances may provide opportunities for some migrating species to establish in otherwise competitive environments. The size of and time since disturbance may determine the establishment ability of these species. We investigated gap dynamics of an old-growth red pine (Pinus resinosa Sol. ex Aiton) forest in the Great Lakes-St. Lawrence forest in northern Ontario, Canada, a transition zone between temperate and boreal forest. We investigated the effects of gaps of different sizes and ages on tree species abundance and basal area. Our results show that tree species from the temperate forest further south, such as red maple (Acer rubrum L.), red oak (Quercus rubra L.), and white pine (Pinus strobus L.), establish more often in large, old gaps; however, tree species that have more northern distributions, such as black spruce (Picea mariana Mill.), paper birch (Betula papyrifera Marsh.), and red pine show no difference in establishment ability with gap size or age. These differences in composition could not be attributed to autogenic succession. We conclude that treefall gaps in this forest facilitate the establishment of northward migrating species, potentially providing a pathway for future forest migration in response to recent changes in climate.
预计气候变化将促进物种迁移。在生态过渡带（生态紧张区域），干扰可能为一些迁移物种提供在原本具有竞争力的环境中建立的机会。干扰的大小和时间可能决定这些物种的建立能力。我们调查了加拿大安大略省北部大湖-圣劳伦斯森林中的一个古老的红松（Pinus resinosa Sol. ex Aiton）林的林隙动态，该地区是温带森林和北方森林之间的过渡带。我们调查了不同大小和年龄的林隙对树种丰度和基部面积的影响。我们的结果表明，来自更南部温带森林的树种，如红枫（Acer rubrum L.）、红橡木（Quercus rubra L.）和白松（Pinus strobus L.），更常出现在大而古老的林隙中；然而，分布更靠北的树种，如黑云杉（Picea mariana Mill.）、纸皮桦（Betula papyrifera Marsh.）和红松，在建立能力方面，林隙的大小或年龄没有差异。这些组成上的差异不能归因于自发生长。我们的结论是，该森林中的树木倒伏林隙促进了向北迁移物种的建立，这可能为未来气候变化导致的森林迁移提供了一种途径。
