...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Ecosystems >Geography of invasion in mountain streams: Consequences of headwater lakefish introductions
【24h】

Geography of invasion in mountain streams: Consequences of headwater lakefish introductions

机译：山区河流入侵的地理环境：引入源头湖水的后果

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The introduction of fish into high-elevation lakes can provide a geographic and demographic boost to their invasion of stream networks, thereby further endangering the native stream fauna. Increasingly, remaining populations of native salmonids are concentrated in fragmented headwater refugia that are protected by physical or biological barriers from introduced fishes that originate in the pervasive source populations established at lower elevations. Although fish introduced near mainstem rivers frequently encounter obstacles to upstream dispersal, such as steep slopes or falls, we found that brook trout (Salvelinus fontinalis) dispersed downstream through channel slopes of 80% and 18-m-high falls. Thus, headwater lake stocking provides source populations that may be capable of invading most downstream habitats, including headwater refugia of native fishes. The extent of additional area invasible from lakes, beyond that invasible from downstream, depends on the geography of the stream network, particularly the density and distribution of headwater lakes and their location relative to barriers inhibiting upstream dispersal. In the thermal and trophic environments downstream of lakes, fish commonly grow faster and thus mature earlier and have higher fecundity-at-age than their counterparts in other high-elevation streams. The resulting higher rates of population growth facilitate invasion. Larger body sizes also potentially aid the fish in overcoming barriers to invasion. Trout introductions to high-elevation headwater lakes thus pose disproportionately large risks to native fishes-even when the place of introduction may appear to be spatially dissociated from populations of the native species. Mapping the potential invasible area can help to establish priorities in stocking and eradication efforts.
机译：将鱼引入高海拔湖泊可以为它们对河流网络的入侵提供地理和人口统计学上的推动，从而进一步危害本地河流动物。剩余的本地鲑科鱼类越来越多地集中在零散的源头避难所中，这些源头受到了物理或生物屏障的保护，免受来自较低海拔建立的普遍来源种群的引进鱼类的物理或生物屏障的保护。尽管在主干河附近引入的鱼类经常遇到上游扩散的障碍，例如陡峭的山坡或瀑布，但我们发现溪鳟（Salvelinus fontinalis）通过80％的河道坡度和18米高的瀑布向下游扩散。因此，源头湖泊的放养提供了可能入侵大多数下游生境的源种群，包括本地鱼类的源头避难所。除下游可入侵的湖泊外，湖泊可入侵的其他区域的范围还取决于河流网络的地理位置，特别是上游水域湖泊的密度和分布及其相对于阻碍上游扩散的障碍物的位置。在湖泊下游的高温和营养环境中，鱼类通常比其他高海拔河流中的鱼类生长更快，因此成熟更早，并且在年龄上的繁殖力更高。随之而来的更高的人口增长率促进了入侵。较大的体形还可能帮助鱼类克服入侵的障碍。因此，将鳟鱼引入高海拔源头湖泊会给当地鱼类带来不成比例的巨大风险，即使引入地点在空间上似乎与当地物种的种群无关。绘制潜在的可入侵区域的地图有助于确定放牧和根除工作的重点。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号