Data from: Unravelling seed dispersal through fragmented landscapes: frugivore species operate unevenly as mobile links

Seed dispersal constitutes a pivotal process in an increasingly fragmented world, promoting population connectivity, colonization and range shifts in plants. Unveiling how multiple frugivore species disperse seeds through fragmented landscapes, operating as mobile links, has remained elusive owing to methodological constraints for monitoring seed dispersal events. We combine for the first time DNA barcoding and DNA microsatellites to identify, respectively, the frugivore species and the source trees of animal-dispersed seeds in forest and matrix of a fragmented landscape. We found a high functional complementarity among frugivores in terms of seed deposition at different habitats (forest vs. matrix), perches (isolated trees vs. electricity pylons) and matrix sectors (close vs. far from the forest edge), cross-habitat seed fluxes, dispersal distances, and canopy-cover dependency. Seed rain at the landscape-scale, from forest to distant matrix sectors, was characterized by turnovers in the contribution of frugivores and source-tree habitats: open-habitat frugivores replaced forest-dependent frugivores, whereas matrix trees replaced forest trees. As a result of such turnovers, the magnitude of seed rain was evenly distributed between habitats and landscape sectors. We thus uncover key mechanisms behind ‘biodiversity–ecosystem function’ relationships, in this case, the relationship between frugivore diversity and landscape-scale seed dispersal. Our results reveal the importance of open-habitat frugivores, isolated fruiting trees, and anthropogenic perching sites (infrastructures) in generating seed dispersal events far from the remnant forest, highlighting their potential to drive regeneration dynamics through the matrix. This study helps to broaden the ‘mobile link’ concept in seed dispersal studies by providing a comprehensive and integrative view of the way in which multiple frugivore species disseminate seeds through real-world landscapes.

种子扩散在日益破碎化的全球生态系统中是一项核心过程，可促进植物种群的连通性、定植以及分布范围的迁移。由于监测种子扩散事件的方法学限制，阐明多种食果动物（frugivore）如何作为移动链接（mobile links）在破碎化景观中完成种子扩散，长期以来一直是学界尚未解决的难题。我们首次结合DNA条形码（DNA barcoding）与DNA微卫星（DNA microsatellites）技术，分别鉴定破碎化景观中森林与基质生境里动物传播种子的食果动物物种及其源树。研究发现，食果动物在不同生境（森林与基质）、停栖点（孤立树木与输电铁塔）以及基质片区（距林缘近与远）的种子沉积、跨生境种子通量、扩散距离以及冠层覆盖依赖性方面，展现出极高的功能互补性。从森林到远端基质片区的景观尺度种子雨（seed rain），其特征为食果动物贡献与源树生境的类群更替：开阔生境食果动物取代了依赖森林的食果动物，而基质树木取代了森林树木。此类类群更替使得种子雨的总量在不同生境与景观片区中分布均匀。借此，我们揭示了“生物多样性-生态系统功能（biodiversity–ecosystem function）”关系背后的核心机制——就本研究而言，即食果动物多样性与景观尺度种子扩散之间的关联。本研究结果揭示了开阔生境食果动物、孤立结果树木以及人工停栖点（基础设施）在促成远离残存森林的种子扩散事件中的重要性，并凸显了它们驱动基质中植物更新动态的潜力。本研究通过提供多种食果动物物种在真实景观中传播种子的全面整合视角，有助于拓展种子扩散研究中的“移动链接”概念。