Deforestation results in habitat fragmentation, decreasing diversity, and functional degradation. For mangroves, no data are available on the impact of deforestation on the diversity and functionality of the specialized invertebrate fauna, critical for their functioning. We compiled a global dataset of mangrove invertebrate fauna comprising 364 species from 16 locations, classified into 64 functional entities (FEs). For each location, we calculated taxonomic distinctness (Δ+), functional richness (FRi), functional redundancy (FRe), and functional vulnerability (FVu) to assess functional integrity. Δ+ and FRi were significantly related to air temperature but not to geomorphic characteristics, mirroring the global biodiversity anomaly of mangrove trees. Neither of those two indices was linked to forest area, but both sharply decreased in human-impacted mangroves. About 60% of the locations showed an average FRe < 2, indicating that most of the FEs comprised one species only. Notable exceptions were the Eastern Indian Ocean and west Pacific Ocean locations, but also in this region, 57% of the FEs had no redundancy, placing mangroves among the most vulnerable ecosystems on the planet. Our study shows that despite low redundancy, even small mangrove patches host truly multifunctional faunal assemblages, ultimately underpinning their services. However, our analyses also suggest that even a modest local loss of invertebrate diversity could have significant negative consequences for many mangroves and cascading effects for adjacent ecosystems. This pattern of faunal-mediated ecosystem functionality is crucial for assessing the vulnerability of mangrove forests to anthropogenic impact and provides an approach to planning their effective conservation and restoration.

森林砍伐导致栖息地破碎化、多样性下降和功能退化。对于红树林，没有关于森林砍伐对特殊无脊椎动物群的多样性和功能的影响的数据，这对其功能至关重要。我们编译了一个全球红树林无脊椎动物数据集，包括来自 16 个地点的 364 个物种，分为 64 个功能实体 (FE)。对于每个位置，我们计算了分类差异性 (Δ+)、功能丰富度 (FRi)、功能冗余 (FRe) 和功能脆弱性 (FVu) 以评估功能完整性。Δ+和FRi与气温显着相关，与地貌特征无关，反映了全球红树林生物多样性异常。这两个指数都与森林面积无关，但在受人类影响的红树林中，两者都急剧下降。大约 60% 的位置显示平均 FRe < 2，表明大多数 FEs 仅包含一个物种。值得注意的例外是东印度洋和西太平洋地区，但同样在该地区，57% 的 FE 没有冗余，使红树林成为地球上最脆弱的生态系统之一。我们的研究表明，尽管冗余度很低，但即使是小红树林地块也拥有真正多功能的动物群落，最终支撑着它们的服务。然而，我们的分析还表明，即使局部无脊椎动物多样性的轻微丧失也可能对许多红树林产生重大的负面影响，并对邻近的生态系统产生连锁效应。