Spatial Variation in Upper Limits of Coral Cover on the Great Barrier Reef

IF 6.3 1区环境科学与生态学 Q1 ECOLOGY

Global Ecology and Biogeography Pub Date : 2024-10-26 DOI:10.1111/geb.13928

Mariana Álvarez-Noriega, Juan C. Ortiz, Daniela M. Ceccarelli, Michael J. Emslie, Katharina E. Fabricius, Michelle J. Jonker, Marji Puotinen, Barbara J. Robson, Chris M. Roelfsema, Tane H. Sinclair-Taylor, Renata Ferrari

{"title":"Spatial Variation in Upper Limits of Coral Cover on the Great Barrier Reef","authors":"Mariana Álvarez-Noriega, Juan C. Ortiz, Daniela M. Ceccarelli, Michael J. Emslie, Katharina E. Fabricius, Michelle J. Jonker, Marji Puotinen, Barbara J. Robson, Chris M. Roelfsema, Tane H. Sinclair-Taylor, Renata Ferrari","doi":"10.1111/geb.13928","DOIUrl":null,"url":null,"abstract":"<div>\n \n \n <section>\n \n <h3> Aim</h3>\n \n <p>Identifying the maximum coral cover that a coral community can sustain (i.e., its ‘upper limit’) is important for predicting community dynamics and improving management strategies. Here, we quantify the relationship between estimated upper limits and key environmental factors on coral reefs: hard substrate availability, temperature and water clarity.</p>\n </section>\n \n <section>\n \n <h3> Location</h3>\n \n <p>Great Barrier Reef (GBR), Australia (over 1400 km).</p>\n </section>\n \n <section>\n \n <h3> Time Period</h3>\n \n <p>1990 to 2022.</p>\n </section>\n \n <section>\n \n <h3> Major Taxa Studied</h3>\n \n <p>Scleractinian corals.</p>\n </section>\n \n <section>\n \n <h3> Methods</h3>\n \n <p>We used 32 years of data on coral cover around reef perimeters. Each reef was divided into four wave-exposure habitats depending on prevailing wind conditions. For each site, we determined if hard coral cover had reached a plateau or upper limit. Next, we extracted existing estimates of hard substrate availability, modelled water temperature and Secchi depth. Then, we quantified the relationship between these environmental variables and the upper limits.</p>\n </section>\n \n <section>\n \n <h3> Results</h3>\n \n <p>We found varying upper limits across the GBR, with a median of 33% coral cover and only 17% of the estimated upper limits exceeded 50% coral cover. Upper limits increased towards the southern reefs. Our results show that upper limits increased with increasing hard substrate availability and decreased with temperature and, to a lesser extent, with water clarity.</p>\n </section>\n \n <section>\n \n <h3> Main Conclusions</h3>\n \n <p>The upper limits estimated in this study are much lower than what is commonly assumed when modelling ecological dynamics, most likely resulting in predicted recovery rates being inappropriately high. Although hard substrate ultimately restricted upper limits, there are mechanisms constraining the proportion of hard substrate that is covered by hard corals. The negative relationship between temperature and upper limits cannot be explained by changes in macroalgal abundance but may be related to changes in species composition. The quantitative relationships between the upper limits of coral cover and environmental variables will provide critical information to prioritise sites for management interventions.</p>\n </section>\n </div>","PeriodicalId":176,"journal":{"name":"Global Ecology and Biogeography","volume":"33 12","pages":""},"PeriodicalIF":6.3000,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Global Ecology and Biogeography","FirstCategoryId":"93","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/geb.13928","RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ECOLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

Aim

Identifying the maximum coral cover that a coral community can sustain (i.e., its ‘upper limit’) is important for predicting community dynamics and improving management strategies. Here, we quantify the relationship between estimated upper limits and key environmental factors on coral reefs: hard substrate availability, temperature and water clarity.

Location

Great Barrier Reef (GBR), Australia (over 1400 km).

Time Period

1990 to 2022.

Major Taxa Studied

Scleractinian corals.

Methods

We used 32 years of data on coral cover around reef perimeters. Each reef was divided into four wave-exposure habitats depending on prevailing wind conditions. For each site, we determined if hard coral cover had reached a plateau or upper limit. Next, we extracted existing estimates of hard substrate availability, modelled water temperature and Secchi depth. Then, we quantified the relationship between these environmental variables and the upper limits.

Results

We found varying upper limits across the GBR, with a median of 33% coral cover and only 17% of the estimated upper limits exceeded 50% coral cover. Upper limits increased towards the southern reefs. Our results show that upper limits increased with increasing hard substrate availability and decreased with temperature and, to a lesser extent, with water clarity.

Main Conclusions

The upper limits estimated in this study are much lower than what is commonly assumed when modelling ecological dynamics, most likely resulting in predicted recovery rates being inappropriately high. Although hard substrate ultimately restricted upper limits, there are mechanisms constraining the proportion of hard substrate that is covered by hard corals. The negative relationship between temperature and upper limits cannot be explained by changes in macroalgal abundance but may be related to changes in species composition. The quantitative relationships between the upper limits of coral cover and environmental variables will provide critical information to prioritise sites for management interventions.

查看原文本刊更多论文

大堡礁珊瑚覆盖上限的空间变化

目的确定珊瑚群落可维持的最大珊瑚覆盖率（即 "上限"）对于预测群落动态和改进管理策略非常重要。在此，我们对珊瑚礁的估计上限与关键环境因素（硬基质可用性、温度和水透明度）之间的关系进行了量化。根据盛行风的条件，每个珊瑚礁被划分为四个波浪暴露栖息地。对于每个地点，我们都要确定硬珊瑚覆盖率是否达到了高原或上限。接着，我们提取了现有的硬底质可用性估计值、模拟水温和 Secchi 深度。结果我们发现整个 GBR 的上限各不相同，珊瑚覆盖率的中位数为 33%，只有 17% 的估计上限超过了 50%。上限在南部珊瑚礁有所增加。我们的结果表明，上限随着硬底质可用性的增加而增加，随着温度的升高而降低，在较小程度上随着水透明度的升高而降低。主要结论本研究估计的上限远低于模拟生态动态时通常假设的上限，很可能导致预测的恢复率过高。虽然硬底质最终限制了上限，但硬珊瑚覆盖的硬底质比例受到机制限制。温度与上限之间的负相关关系无法用大型藻类丰度的变化来解释，但可能与物种组成的变化有关。珊瑚覆盖上限与环境变量之间的定量关系将为确定管理干预地点的优先次序提供重要信息。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Global Ecology and Biogeography 环境科学-生态学

CiteScore

12.10

自引率

3.10%

发文量

170

审稿时长

3 months

期刊介绍： Global Ecology and Biogeography (GEB) welcomes papers that investigate broad-scale (in space, time and/or taxonomy), general patterns in the organization of ecological systems and assemblages, and the processes that underlie them. In particular, GEB welcomes studies that use macroecological methods, comparative analyses, meta-analyses, reviews, spatial analyses and modelling to arrive at general, conceptual conclusions. Studies in GEB need not be global in spatial extent, but the conclusions and implications of the study must be relevant to ecologists and biogeographers globally, rather than being limited to local areas, or specific taxa. Similarly, GEB is not limited to spatial studies; we are equally interested in the general patterns of nature through time, among taxa (e.g., body sizes, dispersal abilities), through the course of evolution, etc. Further, GEB welcomes papers that investigate general impacts of human activities on ecological systems in accordance with the above criteria.