Changes in Aspen Communities Over 30 Years in Gunnison County, Colorado
Changes in Aspen Communities Over 30 Years in Gunnison County, Colorado
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科罗拉多州甘尼森县阿斯彭社区 30 年来的变化
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
M. Morgan
中科院分区：
文献类型：
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作者：
J. L. Crawford;S. Mcnulty;J. Sowell;M. Morgan
摘要对美国科罗拉多州Crested Butte附近19个白杨（Populus tremuloides）林分的林冠和林下植被进行了研究，并于1994年进行了重新采样，以评价白杨群落的演替状况。30年后，杨树基材面积基本不变，但总乔木数减少了23%。超过18cm dbh的白杨多出42%。林下物种保持相对不变；以盖度计，1964年最占优势的4种草木（Thalictrum fendleri）、白蜡草（Lathyrus leucanthus）、苔草（Carex geyeri）和紫穗草（Ligusticum porteri）在1994年也相当丰富。针叶林的林分从6个增加到10个，但针叶林的基材面积和乔木总数在30年内保持不变。这些结果表明，顶丘地区的白杨林群落是持久的，而云杉和冷杉可能会逐渐取代一些白杨林，特别是在n面斜坡上，这种取代可能需要几个世纪的时间。
Abstract The canopy and understory vegetation of 19 aspen (Populus tremuloides) stands near Crested Butte, Colorado, were characterized in 1964 and were resampled in 1994 to assess the successional status of aspen communities. After 30 yr, aspen basal area was unchanged although the total number of trees decreased by 23%. There were 42% more aspen over 18 cm dbh. Understory species remained relatively unchanged; Thalictrum fendleri, Lathyrus leucanthus, Carex geyeri and Ligusticum porteri, the four most dominant species, as measured by cover, in 1964 were also abundant in 1994. Conifer basal area and the total number of trees remained constant over 30 yr, though the number of stands with conifers increased from six to 10. These results suggest that the aspen communities in the Crested Butte area are persistent, and while Picea engelmannii and Abies lasiocarpa may gradually replace some aspen stands, particularly on N-facing slopes, this replacement may take centuries.