College of Science and Engineering, James Cook University, Townsville, Queensland, Australia.
TropWATER (Centre for Tropical Water and Aquatic Ecosystem Research), James Cook University, Townsville, Queensland, Australia.
PLoS One. 2019 Apr 17;14(4):e0215350. doi: 10.1371/journal.pone.0215350. eCollection 2019.
Habitat valuation can provide an objective basis for the prioritisation of conservation and restoration actions. The attribution of fisheries production to particular habitat units is an important measure of value, but is difficult to estimate. Using the case study of habitat use by juvenile banana prawns in a tropical estuary, we assessed the potential to produce valid value estimates at two spatio-conceptual scales: estuary reach and whole estuary. Additionally, we also explore the potential to produce meaningful value estimates at the scale of whole estuary contribution to the offshore fisheries stock. A diversity of potential and actual sources of error and logical problems means that quantification at any scale is at best of uncertain validity and produces estimates that are likely to produce unreliable results if treated as quantitative inputs to production models. Estimates for the whole estuary were the most viable, although still requiring substantial assumptions that may or may not be reasonable in particular situations. Estimates for individual habitats required the unreasonable assumption of limited prawn movement, while estimates of contribution of an estuary to the fishery required difficult-to-obtain and usually unavailable information. Because low occupancy habitats can have trophic value, we also used stable isotope analysis to assess the importance of mangroves and saltmarshes to prawn nutrition. No particular habitat was of critical trophic importance, again suggesting that the habitat-production link is most usefully assessed at the whole-of-estuary scale. While valuable and required to support targeted ecosystem management and protection and restoration efforts, valid estimates of the contribution of particular units to fisheries are likely to be unachievable in many situations.
生境评估可为保护和恢复行动的优先级排序提供客观依据。将渔业产量归因于特定生境单元是衡量价值的重要手段，但很难估计。本研究以热带河口幼虾对生境的利用为例，评估了在两个空间概念尺度上（河口段和整个河口）产生有效价值估计的潜力：河口段和整个河口。此外，我们还探讨了在整个河口对近海渔业资源的贡献尺度上产生有意义的价值估计的潜力。各种潜在的和实际的误差源和逻辑问题意味着在任何尺度上的量化都最多是不确定的有效性，并产生如果将其视为生产模型的定量投入，则可能产生不可靠结果的估计。整个河口的估计是最可行的，尽管仍然需要大量的假设，这些假设在特定情况下可能合理，也可能不合理。对单个生境的估计需要对虾类有限移动的不合理假设，而对河口对渔业贡献的估计则需要难以获得且通常无法获得的信息。由于低占有生境可能具有营养价值，我们还使用稳定同位素分析来评估红树林和盐沼对虾类营养的重要性。没有特别的生境具有关键的营养重要性，这再次表明，在整个河口尺度上评估生境-生产关系最为有用。尽管对于支持有针对性的生态系统管理、保护和恢复工作非常有价值且需要，但在许多情况下，特定单元对渔业的贡献的有效估计可能无法实现。
