Colonization of the polar willow Salix polarison the early stage of succession after glacier retreat in the High Arctic, Ny-Alesund, Svalbard.
Colonization of the polar willow Salix polarison the early stage of succession after glacier retreat in the High Arctic, Ny-Alesund, Svalbard.
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在斯瓦尔巴特群岛新奥勒松高纬度地区，冰川退缩后，极地柳柳在演替的早期阶段开始定植。
DOI：
10.1111/j.1751-8369.2010.00170.x
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发表时间：
2010
期刊：
影响因子：
1.9
通讯作者：
Koizumi H. and Uchida M.
中科院分区：
文献类型：
--
作者：
Nakatsubo T.;Fujiyoshi M.;Yoshitake S.;Koizumi H. and Uchida M.
极地杨柳（Salix polaris）在斯瓦尔巴特群岛新勒松冰川消退区的演替晚期占优势，而在早期则很少发现，当时紫色虎耳草（Saxifraga oppositifolia）占优势。为了阐明从虎耳草阶段到柳阶段的演替变化模式和机制，我们研究了柳在入侵虎耳草优势地的演替阶段的分布格局、大小结构和生境条件。目前的分布格局和过去拍摄的航空照片表明，沙柳在该地点的殖民开始在过去的70年。在30 m × 30 m的样方中，调查到柳属115株（其中雄柳22株，雌柳13株，未知80株）。虽然最大的个体的尺寸为2000 cm 2（长度×最大宽度），但大多数（84%）个体小于100 cm 2。幼苗的大小分布，推断从叶痕数，表明每年的招聘是轻微的。在观察到的个体中，约75%的个体在裸露的地面上定居，只有4个个体在虎耳草群落中生长。结果表明，沙柳定植后土壤含水量、碳、氮含量与定植前无显著差异。这些结果表明，在种子生产，发芽和/或幼苗建立ofSalix的困难，而不是土壤形成的前物种（虎耳草），限制了早期阶段的定殖。
The polar willow (Salix polaris), predominant in the late successional stage in deglaciated areas of Ny-Ålesund, Svalbard, is rarely found in the early stage, when purple saxifrage (Saxifraga oppositifolia) dominates. To elucidate the pattern and the mechanism of successional change from theSaxifragastage to theSalixstage, we examined the distribution pattern, size structure and habitat conditions of a colonizing Salix population in the seral stage whereSalixwas invading Saxifraga-dominated sites. The present distribution pattern and aerial photographs taken in the past suggest thatSalixcolonization at this site commenced within the last 70 years. We found 115Salixindividuals (22 male, 13 female and 80 unknown) in a 30 m × 30 m quadrat on the seral stage. Although the largest individual had a size of 2000 cm2(length × maximum width), the majority (84%) of individuals were smaller than 100 cm2. The seedling size distribution, as inferred from the leaf scar number, indicated that annual recruitment was slight. Of the individuals observed about 75% had colonized bare ground; only four individuals grew withinSaxifragacolonies. No significant difference was found in soil characteristics (water content, and carbon and nitrogen concentrations) between the seral stage and the earlier stage prior to colonization bySalix. These results suggest that difficulties in seed production, germination and/or seedling establishment ofSalix, rather than soil formation by preceding species (Saxifraga), limits the early-stage colonization bySalix.