Effects of Grizzly Bear Digging on Alpine Plant Community Structure
Effects of Grizzly Bear Digging on Alpine Plant Community Structure
复制标题
灰熊挖掘对高山植物群落结构的影响
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
M. Loso
中科院分区：
文献类型：
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作者：
D. Doak;M. Loso
在阿拉斯加高山苔原，灰熊挖掘深洞寻找地松鼠，但很少有研究测试灰熊，或其他大型哺乳动物，在维持植物群落结构的重要性。我们研究了43熊挖，问他们如何影响植物物种丰富度和多样性，克隆模式，和植物不同的克隆生长策略。熊从挖掘中移除大部分植被，恢复挖掘的物种丰富度低于邻近的成熟苔原。然而，成熟的苔原单独，有显着较少的物种比成熟的苔原和熊挖掘的总和，这表明熊挖掘有助于苔原社区的整体丰富性。挖掘开发最高的植物丰富度和多样性在中间的年龄，但即使在新的挖掘的整体物种组成是类似于邻近的苔原。不同克隆生长型的植物对熊挖的反应不同。这两个物种显着更常见的挖掘比其他地方有一个nonspreading（方阵）克隆的习惯，而六种植物中的五个显着更常见的成熟苔原能够快速，扩散（游击队）克隆生长。总体而言，熊挖掘造成不太明显的影响，在其他一些系统中的群落组成比哺乳动物diabetes，可能是因为亚北极高山苔原已经具有高水平的非生物干扰。
Abstract In Alaskan alpine tundra, grizzly bears excavate deep holes in search of ground squirrels, but few studies have tested the importance of grizzlies, or other large mammals, in maintaining plant community structure. We examined 43 bear digs, asking how they affect plant species richness and diversity, recolonization patterns, and plants with different clonal growth strategies. Bears remove most vegetation from digs, and recovering digs had lower species richness than adjacent mature tundra. Mature tundra alone, however, had significantly fewer species than mature tundra and bear digs combined, suggesting that bear digs contribute to the overall richness of tundra communities. Digs develop the highest plant richness and diversity at intermediate ages, but even in new digs the overall species composition is similar to adjacent tundra. Plants of different clonal growth forms reacted differently to bear digs. The two species significantly more common in digs than elsewhere have a nonspreading (phalanx) clonal habit, whereas five of six plant species significantly more common in mature tundra are capable of rapid, diffuse (guerrilla) clonal growth. Overall, bear digs cause less pronounced effects on community composition than mammalian diggings in some other systems, possibly because subarctic alpine tundra is already characterized by high levels of abiotic disturbance.