• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>San Francisco Estuary and Watershed Science >Salmon Lifecycle Considerations to Guide Stream Management: Examples from California’s Central Valley
【24h】

Salmon Lifecycle Considerations to Guide Stream Management: Examples from California’s Central Valley

机译：鲑鱼生命周期注意事项以指导河流管理：来自加利福尼亚中央谷地的实例

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A primary goal of the Central Valley Project Improvement Act is to at least double natural production of Chinook salmon (Oncorhynchus tshawytscha), in California Central Valley (CV) streams on a sustainable basis. Achievement relies on restoration actions that involve both discharge (e.g., dam releases) and non-discharge (e.g., gravel augmentation, screening) components. Annual adult and juvenile abundance estimates for individual watersheds must be tracked to assess effectiveness of individual actions. However, to date, no substantial efforts have been taken to demonstrate success or deficiencies of their implementations. A major challenge in interpreting time series of counts at any one life stage is that they reflect the cumulative effects of both freshwater and marine factors over the full life cycle. To address this issue, we developed a conceptual framework based on ratios of the abundance of consecutive CV fall-run Chinook salmon life stages and how variation in these ratios tracks key independent variables during the freshwater portion of the life cycle. Model validation with several case studies shows that estimates of previous stage class production correlate well with estimated individuals produced in the next class, indicating that transition rates tend to vary within a constrained range, and that monitoring programs generate abundance estimates whose errors are small enough not to swamp out the underlying signal. When selected environmental parameters were added to demonstration models, abundance estimates were more closely modeled and several tested relationships between environmental drivers and life-stage transition rates proved consistent across watersheds where data were available. Results from this generalized life-stage conceptual model suggest a potential framework for tracking the success of actions meant to improve survival for a given life stage within an individual stream and for determining how successive stages respond to these changes. Though examples are provided for CV Chinook salmon, these concepts can be applied wherever migratory salmonid populations and associated environmental data are being adequately monitored.
机译：《中央谷地项目改进法案》的主要目标是，在可持续的基础上，使加利福尼亚中央谷地（CV）溪流的奇努克鲑鱼（Oncorhynchus tshawytscha）的自然产量至少增加一倍。成就依赖于既涉及排放（例如大坝释放）又涉及不排放（例如砾石充填，筛选）的恢复行动。必须跟踪单个流域的年度成年和少年丰度估计，以评估单个行动的有效性。但是，迄今为止，尚未采取任何实质性措施来证明其实现的成功或不足。解释任何生命阶段的时间序列的一个主要挑战是，它们反映了整个生命周期中淡水和海洋因素的累积影响。为了解决此问题，我们基于连续CV下降运行的奇努克鲑鱼生命阶段的丰度比率以及生命周期中淡水部分中这些比率的变化如何跟踪关键的独立变量，开发了一个概念框架。通过一些案例研究进行的模型验证表明，前一班的产量估算与下一班的生产估算值具有很好的相关性，这表明过渡率倾向于在一个受限范围内变化，并且监控程序会生成丰度估算，其误差足够小而不会淹没底层信号。当将选定的环境参数添加到演示模型时，对丰度估算进行了更紧密的建模，并且在可获得数据的流域中，环境驱动因素与生命阶段过渡率之间的几种测试关系证明是一致的。该广义生命阶段概念模型的结果提出了一个潜在的框架，该框架可用于跟踪旨在提高单个流中给定生命阶段生存率并确定连续阶段如何应对这些变化的行动的成功。尽管提供了CV奇努克鲑鱼的示例，但是这些概念可以应用于任何地方的鲑鱼种群和相关环境数据得到适当监测的地方。

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