Colonization and development of stream communities across a 200-year gradient in Glacier Bay National Park, Alaska, USA
Colonization and development of stream communities across a 200-year gradient in Glacier Bay National Park, Alaska, USA
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DOI：
10.1139/cjfas-57-11-2319
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发表时间：
2000-11-01
影响因子：
2.4
通讯作者：
Magnusson, K
中科院分区：
文献类型：
--
作者：
Milner, AM;Knudsen, EE;Magnusson, K
1997年5月，在阿拉斯加东南部的冰川湾国家公园，研究了16条不同年龄和不同发展阶段的河流的物理和生物变量。的数量的微型甲壳动物和大型无脊椎动物类群和幼鱼的丰度和多样性显着更大的老流。微甲壳动物的多样性有关的数量的instantly木材和百分比池栖息地，而大型无脊椎动物类群的数量与床的稳定性，instantly木材的数量，和百分比池栖息地。蜉蝣目对溪流底栖生物群落的贡献率随溪流年龄和粗颗粒有机质含量的增加而显著增加。少年多莉瓦登（红点鲑）占主导地位的年轻的流，但少年银鲑（Oncorhynchus kisutch）的丰度更大的老流与增加池栖息地。上游湖泊显着影响通道的稳定性，摇蚊百分比，总的大型无脊椎动物和小型底栖动物的丰度，鱼类覆盖率。稳定同位素分析表明，氮富集从海洋来源的大型无脊椎动物和幼鱼在老流建立鲑鱼运行。研究结果封装在流发展的概念性摘要，提出流组合与陆地，海洋和湖泊生态系统的直接相互作用来确定。
In May 1997, physical and biological variables were studied in 16 streams of different ages and contrasting stages of development following glacial recession in Glacier Bay National Park, southeast Alaska. The number of microcrustacean and macroinvertebrate taxa and juvenile fish abundance and diversity were significantly greater in older streams. Microcrustacean diversity was related to the amount of instream wood and percent pool habitat, while the number of macroinvertebrate taxa was related to bed stability, amount of instream wood, and percent pool habitat. The percent contribution of Ephemeroptera to stream benthic communities increased significantly with stream age and the amount of coarse benthic organic matter. Juvenile Dolly Varden (Salvelinus malma) were dominant in the younger streams, but juvenile coho salmon (Oncorhynchus kisutch) abundance was greater in older streams associated with increased pool habitat. Upstream lakes significantly influenced channel stability, percent Chironomidae, total macroinvertebrate and meiofaunal abundance, and percent fish cover. Stable isotope analyses indicated nitrogen enrichment from marine sources in macroinvertebrates and juvenile fish in older streams with established salmon runs. The findings are encapsulated in a conceptual summary of stream development that proposes stream assemblages to be determined by direct interactions with the terrestrial, marine, and lake ecosystems.