Exploring the effectiveness of using beaver as an aquatic ecosystem restoration tool

海狸因其创造、破坏和改变水生栖息地的能力而被称为生态系统工程师。海狸草甸形成理论是一个概念框架，解释和预测海狸如何影响形成包括河岸带在内的河谷的物理过程。由于草甸理论对海狸活动对生态系统的影响进行了全面的描述，并具有预测海狸活动后可能的未来（演替途径）的能力，因此草甸理论在水生生态系统恢复策略方面具有相当大的前景。然而，为了将海狸草甸形成理论应用于实践，需要回答关于海狸如何探测和塑造水生生态系统的关键问题。在水生环境中，海狸调节的水文和地貌功能范围是什么？还有，我们在哪些地方可以和不可以使用海狸作为一个可行的恢复选择？我建议通过研究海狸如何在三组占领历史中塑造和探索水生生态系统来解决这些问题：原生的，外来的，重新引入的。在它们的原生栖息地，实地观察和实验将用于评估海狸如何以及在哪里为容易发生洪水和干旱的地区提供增强的水文恢复能力，加拿大落基山脉的东部斜坡。在它们的异国栖息地（巴塔哥尼亚南部的沼泽），恢复实验将用于评估水文过程和土壤水力特性变化的范围和持久性。在它们重新引入的栖息地，我们将确定海狸是否在它们占据的栖息地触发了矿物沉积物的增加过程，并启动了海狸草甸的形成。我们将把研究重点放在苏格兰的溪流上，在消失了400年之后，海狸最近重新被引入了苏格兰。总而言之，拟议的研究应该对其工程能力影响的变化的范围和持久性产生新的见解。通过研究获得的见解将有助于促进对如何最好地与生物合作，以最好地保护和恢复退化栖息地中的水生生态系统功能的理解。我们期望本研究能为环境管理者利用海狸草甸形成理论指导水生生态系统恢复工作提供具体的建议。拟开展的研究包括通过博士后培养大量高素质的本科生。计划中的培训项目将使学员能够满足加拿大及其他地区对技术专家、创新者、领导者和有影响力的研究人员的需求。

Beavers are known ecosystem engineers due to their ability to create, destroy and modify aquatic habitats. The beaver meadow formation theory is a conceptual framework that explains and predicts how beavers influence the physical processes that form stream valleys including the riparian zone. The meadow theory holds considerable promise in informing aquatic ecosystem restoration strategy owing to the theory’s holistic description of ecosystem impacts of beaver activities and its power in predicting possible futures (successional pathways) post-beaver. Yet, key questions on how beaver plumb and shape aquatic ecosystems need answering in order to put beaver meadow formation theory to use in practice. What is the range of hydrologic and geomorphic functions that beavers mediate in aquatic environments? And, where can and cannot we use beavers as a viable restoration option? I propose to address these questions through studying how beaver shape and plumb aquatic ecosystems across the three sets of occupation histories: native, exotic, reintroduced. In their native habitat, field observations and experiments will be used to evaluate how and where beaver offer enhanced hydrologic resiliency in a region prone to floods and droughts, the eastern slopes of the Canadian Rockies. In their exotic habitat (fens in southern Patagonia), restoration experiments will be used to evaluate the scope and permanence of changes to hydrological processes and soil hydraulic properties. In their reintroduced habitat, we will determine whether beaver have triggered mineral sediment accretion processes in their occupied habitats and initiated the formation of beaver meadows. We will focus that research on streams in Scotland to which beaver were recently reintroduced after a 400 year absence. In all, the proposed research should yield new insights into the scope and permanence of the changes effected by their engineering capabilities. The insights gained through the research will help advance understanding of how to best work with organisms to best protect and restore aquatic ecosystem functions in degraded habitats. We expect the research will also provide concrete advice to environmental managers wanting to use beaver meadow formation theory to guide aquatic ecosystem restoration efforts. The proposed research involves extensive training of highly qualified personnel in the form of undergraduates through postdoctoral fellows. The planned training program will ready trainees to fill the demand for technical experts, innovators, leaders and influential researchers in Canada and beyond.