Swain Timothy D, Vega-Perkins Jesse B, Oestreich William K, Triebold Conrad, DuBois Emily, Henss Jillian, Baird Andrew, Siple Margaret, Backman Vadim, Marcelino Luisa
Department of Civil and Environmental Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA.
Department of Zoology, Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, IL, 60605, USA.
Glob Chang Biol. 2016 Jul;22(7):2475-88. doi: 10.1111/gcb.13276. Epub 2016 Apr 13.
As coral bleaching events become more frequent and intense, our ability to predict and mitigate future events depends upon our capacity to interpret patterns within previous episodes. Responses to thermal stress vary among coral species; however the diversity of coral assemblages, environmental conditions, assessment protocols, and severity criteria applied in the global effort to document bleaching patterns creates challenges for the development of a systemic metric of taxon-specific response. Here, we describe and validate a novel framework to standardize bleaching response records and estimate their measurement uncertainties. Taxon-specific bleaching and mortality records (2036) of 374 coral taxa (during 1982-2006) at 316 sites were standardized to average percent tissue area affected and a taxon-specific bleaching response index (taxon-BRI) was calculated by averaging taxon-specific response over all sites where a taxon was present. Differential bleaching among corals was widely variable (mean taxon-BRI = 25.06 ± 18.44%, ±SE). Coral response may differ because holobionts are biologically different (intrinsic factors), they were exposed to different environmental conditions (extrinsic factors), or inconsistencies in reporting (measurement uncertainty). We found that both extrinsic and intrinsic factors have comparable influence within a given site and event (60% and 40% of bleaching response variance of all records explained, respectively). However, when responses of individual taxa are averaged across sites to obtain taxon-BRI, differential response was primarily driven by intrinsic differences among taxa (65% of taxon-BRI variance explained), not conditions across sites (6% explained), nor measurement uncertainty (29% explained). Thus, taxon-BRI is a robust metric of intrinsic susceptibility of coral taxa. Taxon-BRI provides a broadly applicable framework for standardization and error estimation for disparate historical records and collection of novel data, allowing for unprecedented accuracy in parameterization of mechanistic and predictive models and conservation plans.
随着珊瑚白化事件变得越来越频繁和严重，我们预测和减轻未来事件的能力取决于我们解读先前事件模式的能力。不同珊瑚物种对热应激的反应各不相同；然而，在全球记录白化模式的努力中，珊瑚组合的多样性、环境条件、评估方案以及应用的严重程度标准，给制定一个特定分类群反应的系统指标带来了挑战。在此，我们描述并验证了一个新框架，用于标准化白化反应记录并估计其测量不确定性。对316个地点的374个珊瑚分类群在1982 - 2006年期间的特定分类群白化和死亡率记录（共2036条）进行标准化，以计算受影响组织面积的平均百分比，并通过对一个分类群出现的所有地点的特定分类群反应进行平均，计算出特定分类群白化反应指数（分类群 - BRI）。珊瑚之间的差异白化差异很大（平均分类群 - BRI = 25.06 ± 18.44%，±标准误）。珊瑚的反应可能不同，原因在于共生体在生物学上存在差异（内在因素）、它们暴露于不同的环境条件（外在因素），或者报告存在不一致性（测量不确定性）。我们发现，在给定的地点和事件中，外在因素和内在因素具有相当的影响（分别解释了所有记录中白化反应方差的60%和40%）。然而，当将各个分类群在不同地点的反应进行平均以获得分类群 - BRI时，差异反应主要由分类群之间的内在差异驱动（解释了分类群 - BRI方差的65%），而非不同地点的条件（解释了6%），也不是测量不确定性（解释了29%）。因此，分类群 - BRI是珊瑚分类群内在易感性的一个可靠指标。分类群 - BRI为不同历史记录的标准化和误差估计以及新数据的收集提供了一个广泛适用的框架，使得在机械模型和预测模型以及保护计划的参数化方面能够达到前所未有的准确性。
