Collaberative Research: Ultimate Causation of Insect Drift:An Evaluation of Active and Passive Models

生活在溪流底质上或溪流底质内的昆虫“漂流” 在大量的下游和一个明显的夜间 节奏 昆虫漂移是跑步的独特特性之一 沃茨，尽管有许多研究， 也是一个令生态学家困惑的问题 概念和技术的最新发展现在允许 对生物体为何漂移， 度漂移进入是主动与被动，以及相对的 生物与非生物原因的影响。 本研究是 目的是了解昆虫在 觅食事件和捕食风险的背景。 夜间性已被令人满意地解释为风险 捕食假说 为什么漂移存在两种解释 发生：作为夜间活动的被动和意外后果 觅食活动，或作为一个积极的和有目的的过程， 栖息地搜索/分散，与资源枯竭有关。 而 被动模式被广泛接受，最近的工作证明 文件的弱点，被动机制和一个重要的 一个积极的机制。 这项研究使用了一种组合 实地取样以及实验室和实地实验， 五个目标，测试多个假设， 漂移行为的潜在机制。 其完成应 有助于更好地理解 下游漂移的主动和被动解释， 仍然是河流生态学中尚未解决的主要问题之一。

Insects living on or within the substrate of streams "drift" downstream in substantial numbers and with a pronounced nocturnal rhythm. Insect drift is one of the unique properties of running waters and, despite numerous studies, it remains both a challenge and a puzzle to lotic ecologists. Recent developments of concepts and techniques now allow for a concerted attack on the issues of why organisms drift, to what degree drift entry is active vs. passive, and the relative influence of biotic vs. abiotic causes. This research is directed toward the goal of understanding insect drift within the context of foraging events and risk of predation. Nocturnality has been satisfactorily explained by the risk of predation hypothesis. Two explanations exist for why drift occurs: as the passive and accidental consequence of nocturnal foraging activity, or as an active and purposeful process of habitat search/dispersal, related to resource depletion. While the passive model is widely accepted, evidence from recent work documents weaknesses in the passive mechanism and a significant role for an active mechanism. This research uses a combination of field sampling and laboratory and field experiments to address five objectives that test multiple hypotheses concerning the mechanism(s) underlying drift behavior. Their completion should lead to an improved understanding of the relative contributions of active and passive explanations of downstream drift, which remains one of the major, unresolved issues in river ecology.