Many studies have shown that biodiversity regulates multiple ecological functions that are needed to maintain the productivity of a variety of ecosystem types. What is unknown is how human activities may alter the ‘multifunctionality’ of ecosystems through both direct impacts on ecosystems and indirect effects mediated by the loss of multifaceted biodiversity. Using an extensive database of 72 lakes spanning four large Neotropical wetlands in Brazil, we demonstrate that species richness and functional diversity across multiple larger (fish and macrophytes) and smaller (microcrustaceans, rotifers, protists and phytoplankton) groups of aquatic organisms are positively associated with ecosystem multifunctionality. Whereas the positive association between smaller organisms and multifunctionality broke down with increasing human pressure, this positive relationship was maintained for larger organisms despite the increase in human pressure. Human pressure impacted multifunctionality both directly and indirectly through reducing species richness and functional diversity of multiple organismal groups. These findings provide further empirical evidence about the importance of aquatic biodiversity for maintaining wetland multifunctionality. Despite the key role of biodiversity, human pressure reduces the diversity of multiple groups of aquatic organisms, eroding their positive impacts on a suite of ecological functions that sustain wetlands.

许多研究表明，生物多样性调节着维持各种生态系统类型生产力所需的多种生态功能。未知的是人类活动如何通过对生态系统的直接影响和多方面生物多样性丧失所介导的间接影响来改变生态系统的“多功能性”。使用涵盖巴西四个大型新热带湿地的 72 个湖泊的广泛数据库，我们证明了多个较大（鱼类和大型植物）和较小（微甲壳动物、轮虫、原生生物和浮游植物）水生生物群的物种丰富度和功能多样性与生态系统多功能性。尽管随着人类压力的增加，较小生物体与多功能性之间的正相关关系被打破，尽管人类压力增加了，但对于较大的生物体，这种正相关关系仍然存在。人类压力通过减少多个生物群落的物种丰富度和功能多样性，直接或间接地影响了多功能性。这些发现进一步证明了水生生物多样性对维持湿地多功能性的重要性。尽管生物多样性发挥着关键作用，但人类压力降低了多类水生生物的多样性，削弱了它们对维持湿地的一系列生态功能的积极影响。这些发现进一步证明了水生生物多样性对维持湿地多功能性的重要性。尽管生物多样性发挥着关键作用，但人类压力降低了多类水生生物的多样性，削弱了它们对维持湿地的一系列生态功能的积极影响。这些发现进一步证明了水生生物多样性对维持湿地多功能性的重要性。尽管生物多样性发挥着关键作用，但人类压力降低了多类水生生物的多样性，削弱了它们对维持湿地的一系列生态功能的积极影响。