Data for a meta-analysis of the effect of kelp forests on fish communities around the world from observational and experimental studies spanning 1983-2020

Data for Pérez-Matus, A., Micheli, F., Konar, B., Shears, N., Low, N., Okamoto, D., Wernberg, T., Krumhansl, K., Ling, S., Kinsgford, M., Navarrete-Fernandez, T., Ruz, C., and Byrnes, J. 2024. Kelp forests as nursery and foundational habitat for reef fish. Ecology. For the definitive analysis, see the paper. Code is at https://github.com/jebyrnes/fish_kelp_meta.

This data set concerns the effects of kelp on fish community composition. Data was mined as part of the National Center for Ecological Analysis and Synthesis (NCEAS) working group on "Global impacts of climate change on kelp forest ecosystems." It consists of digitized information from studies searched (see methods) examining fish community composition with and without kelp.

To summarize the study, conservation of marine biodiversity requires an understanding of the habitats needed to support and replenish species of interest. It also requires knowledge about the abundance and diversity of multi-species assemblages. Variation in the distribution and composition of kelp forests, one of the most productive marine coastal habitats globally, can have major influences on reef fishes – a group of ecologically and socio-economically important species. In the face of widespread and escalating loss of kelp forests, quantification of these effects is urgently needed to assess and project cascading impacts on biodiversity. Here, we evaluate relationships between kelp forests and associated reef fish populations using a global meta-analysis of experimental kelp removals and comparative surveys of kelp and adjacent non-kelp habitats. These analyses show that kelp forests increase the abundance of reef fishes, though the significance of this effect varied depending on the structural complexity of kelp forests. In experimental studies, kelp forests have a significant positive effect on fish species richness, revealing that kelp act as true foundation species by supporting the diversity of associated multi-species assemblages. Importantly, regardless of kelp forest morphology and type of study (observational or experimental studies), kelp forests enhance the recruitment of early life history stages suggesting they are nursery habitats for many reef fish taxa. Lastly, kelp forests differentially affected species with different functional traits; small body size fishes from low trophic levels (e.g., herbivore and detritivores, micropredators, and mesopredators) and large body size fish from higher trophic level (e.g., piscivores) were both facilitated by kelp forests. Taken together, these results indicate that the loss of kelp forest, particularly those with more complex morphology, can reduce total abundance and diversity of fish, with possible cascading consequences for coastal ecosystem function.

本数据集关联Pérez-Matus,A.、Micheli,F.、Konar,B.、Shears,N.、Low,N.、Okamoto,D.、Wernberg,T.、Krumhansl,K.、Ling,S.、Kinsgford,M.、Navarrete-Fernandez,T.、Ruz,C.及Byrnes,J.于2024年发表于《生态学》（Ecology）的论文《海带林作为礁栖鱼类的育苗场与基础生境》。如需获取完整分析内容，请参阅该论文。数据集配套代码开源地址为：https://github.com/jebyrnes/fish_kelp_meta。

本数据集聚焦海带林（kelp forests）对鱼类群落组成的影响。本数据集的数据通过文献检索与数据挖掘获得，源自国家生态分析与合成中心（National Center for Ecological Analysis and Synthesis, NCEAS）下属的"气候变化对海带林生态系统的全球影响"专题工作小组的研究成果。数据集包含经数字化处理的相关研究信息，这些研究通过对比有无海带林的生境，对鱼类群落组成展开了调查（具体方法参见论文方法部分）。

本研究综述如下：保护海洋生物多样性，需明确目标物种赖以存续与繁衍的生境类型，同时掌握多物种集合的丰度与多样性特征。作为全球生产力最高的近岸海洋生境之一，海带林的分布与组成变化可对礁栖鱼类产生显著影响——这类鱼类兼具重要的生态价值与社会经济价值。当前全球海带林流失范围不断扩大、程度持续加剧，亟需量化上述影响以评估和预测其对生物多样性的级联效应。本研究通过整合全球范围内的海带林移除实验数据，以及对比海带林与邻近无海带林生境的调查数据，开展荟萃分析，以此探究海带林与伴生礁栖鱼类种群的关联。分析结果显示，海带林可提升礁栖鱼类的丰度，但该效应的显著性取决于海带林的结构复杂度。在实验研究中，海带林对鱼类物种丰富度具有显著的正向作用，表明海带林可通过支撑伴生多物种集合的多样性，成为真正的基础物种。值得注意的是，无论海带林的形态特征与研究类型（观测研究或实验研究）如何，海带林均可促进鱼类早期生活史阶段的存活与补充，暗示其为多数礁栖鱼类类群提供了育苗生境。此外，海带林对不同功能性状的鱼类产生差异化影响：低营养级的小型鱼类（如草食性、碎屑食性、微型捕食者及中型捕食者类群）与高营养级的大型鱼类（如肉食性鱼类）均能从海带林中获益。综合来看，上述结果表明，海带林的流失（尤其是结构复杂度较高的海带林）会降低鱼类的总丰度与多样性，进而可能对近岸生态系统功能产生级联影响。