States and rates: Complementary approaches to developing flow‐ecology relationships
States and rates: Complementary approaches to developing flow‐ecology relationships
复制标题
状态和速率：发展流动生态关系的补充方法
DOI：
10.1111/fwb.13001
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发表时间：
2018
影响因子：
2.7
通讯作者：
M. Freeman
中科院分区：
文献类型：
--
作者：
Kit Wheeler;S. Wenger;M. Freeman
认识到流量对河流生境和生物的影响，河流生态学家投入了大量的精力来开发描述流量变化的生态反应的定量预测关系，即流量-生态关系。
用于生成流生态关系的方法可以被认为是一端由纯状态方法、另一端由速率方法所限定的连续体。在纯状态方法中，生态响应是从单一时间测量得出的条件或属性（即状态）的快照。相比之下，速率方法中的生态响应反映了时间变化（即速率），因此依赖于随时间推移进行的重复测量。
在这里，我们详细阐述了生成流生态关系的不同方法（纯状态、速率和我们称为重复状态的中间方法）的基本特征，研究了不同方法在流生态学文献中的常用程度，进行独立分析以说明通过使用与流量大小相关的溪流鱼类多样性数据集应用重复状态和速率方法所取得的不同结果，并确定生态学家在流生态学中应用速率方法的一些不同方式。
我们的文献综述显示，在生成流生态关系方面，重复状态方法（所审查研究的 53%）比纯状态（19%）或速率（12%）方法更常用。其余的混合研究 (17%) 同时使用状态响应和速率响应，因此也依赖于随时间推移的重复测量。
尽管经常收集适合速率方法的数据，但通常使用状态方法来开发流量-生态关系，这些状态方法将生态状态的变化与不同的长期平均流量条件联系起来，而不是与更短的时间间隔内的特定流量序列联系起来。这种流动-生态关系不能生成对变化的流动条件的生态响应的时间特定预测（即特定流动序列后状态的预期变化），也不能描述观察到的变化背后的人口统计过程。虽然在不同的场景中纯态或重复状态方法会很有用，但更频繁地使用速率方法将提高我们测试流生态学假设的能力以及我们对流生态学关系的机械理解。
In recognition of the influence of flow on riverine habitats and organisms, stream ecologists have devoted considerable effort to the development of quantitative predictive relationships describing ecological responses to flow variability, i.e. flow-ecology relationships.
Methods used to generate flow-ecology relationships can be thought of as a continuum bookended by pure states approaches on one end and by rates approaches on the other. In pure states approaches, the ecological response is a snapshot of a condition or property (i.e. a state) derived from a single measurement in time. In contrast, ecological responses in rates approaches reflect temporal change (i.e. a rate) and are thus reliant on repeated measurements made over time.
Here, we elaborate on the fundamental characteristics of different approaches (pure states, rates and an intermediate approach we call repeated states) for generating flow-ecology relationships, examine how commonly the different approaches are used in the flow-ecology literature, conduct an independent analysis to illustrate the different outcomes achieved by applying repeated-states and rates approaches using a dataset for stream fish diversity in relation to flow magnitude, and identify some of the different ways ecologists are applying rates approaches in flow ecology.
Our literature review revealed that repeated-states approaches (53% of reviewed studies) were used far more commonly than either pure states (19%) or rates (12%) approaches to generate flow-ecology relationships. The remaining hybrid studies (17%) used both state and rate responses, and thus also relied on repeated measurements over time.
Despite frequent collection of data suitable for rates approaches, flow-ecology relationships have generally been developed using states approaches that relate changes in ecological states to different long-term average flow conditions, rather than to specific flow sequences over much shorter time intervals. Such flow-ecology relationships cannot generate temporally specific predictions of ecological responses to changing flow conditions (i.e. the expected change in state following a specific flow sequence), nor can they describe demographic processes underlying observed changes. While there are different scenarios in which a pure or repeated-states approach would be useful, more frequent use of rates approaches would increase our ability to test flow-ecology hypotheses and our mechanistic understanding of flow-ecology relationships.
影响因子：
2.2
作者：
Lancaster, Jill;Downes, Barbara J.
通讯作者：
Downes, Barbara J.