The integration of biodiversity knowledge with management needs in coastal protected ecosystems is a current challenge that requires a social-ecological perspective, especially in view of the current scenario regarding climate changes. At the southeastern Brazil, estuaries inside protected areas highlight as a great source of ecosystem services connected to the biodiversity, such as the food provisioning for local communities (i.e. fishery supply). However, climate change models considering the last four decades alert to an annual rainfall increase in the region, threatening the estuarine biodiversity and its associated ecosystem services. Here, we evaluated how estuarine macrofaunal distribution could be used as ecological indicators to support the stakeholders management needs in subtropical Marine Protected Areas (MPAs). The intertidal macrofauna distribution was assessed along physical gradients in estuaries within MPAs of the southeastern Brazil, testing the effects of salinity and sediment properties on taxa richness. Then, implications of these ecological findings were discussed with the local users and managers of the MPAs, aiming to stipulate indicators and management proposals considering the rainfall increase predicted for the region. We found that macrofauna community varied between estuarine zones along the physical gradients. High values of mud and organic content in the sediment were correlated with reduced taxa richness in the upper estuarine zone, indicating high vulnerability of biodiversity to a possible estuarine mud input connected to the expected rainfall increase. Stakeholders noted that this knowledge could assist with spatial planning for an adaptive management of the biodiversity use rules on the MPAs, with focus on the ecosystem services conservation (ecosystem-based management). Stakeholders suggested using biodiversity hotspots to guide estuarine areas classification (no-take zones and sustainable use zones), maintaining the resources use rules adaptable according to the biodiversity changes. In this regard, our data revealed important bioindicators, such as the macrofaunal richness, which can be monitored as “early signals” to assess eventual ecosystem alterations related to the climate changes. These signals can include loss in taxa richness, extirpation of species exclusively found on the lower estuarine zone (sensitives to mud input) and changes in the distribution or abundance of dominant taxa. We suggest that understanding the relationships between macrofaunal indicators and ecosystems services, associated with continuous monitoring, are the key steps to implementing an adaptive ecosystem-based management of these protected estuaries in the current changing scenario, contributing to decision making at local scale that respond to global challenges, as the UN Ocean Decade.

将生物多样性知识与沿海受保护生态系统的管理需求相结合是当前的一项挑战，需要从社会生态角度出发，尤其是考虑到当前的气候变化情景。在巴西东南部，保护区内的河口是与生物多样性相关的生态系统服务的重要来源，例如当地社区的食物供应（即渔业供应）。然而，考虑到过去 40 年的气候变化模型对该地区的年降雨量增加发出警报，威胁着河口生物多样性及其相关的生态系统服务。在这里，我们评估了如何将河口大型动物分布用作生态指标，以支持亚热带海洋保护区 (MPA) 的利益相关者管理需求。沿巴西东南部海洋保护区内河口的物理梯度评估了潮间带大型动物分布，测试了盐度和沉积物特性对类群丰富度的影响。然后，与当地用户和海洋保护区管理人员讨论了这些生态调查结果的影响，旨在根据该地区预测的降雨量增加来制定指标和管理建议。我们发现大型动物群落沿物理梯度在河口区之间变化。沉积物中泥浆和有机物含量的高值与河口上游区的分类群丰富度降低有关，表明生物多样性对与预期降雨量增加相关的可能河口泥浆输入的高度脆弱性。利益相关者指出，这些知识有助于空间规划，以对海洋保护区的生物多样性使用规则进行适应性管理，重点是生态系统服务保护（基于生态系统的管理）。利益相关方建议利用生物多样性热点来指导河口区域分类（禁采区和可持续利用区），保持资源利用规则与生物多样性变化相适应。在这方面，我们的数据揭示了重要的生物指标，例如大型动物丰富度，可以作为“早期信号”进行监测，以评估与气候变化相关的最终生态系统变化。这些信号可能包括类群丰富度的丧失、仅在河口下游地区发现的物种的灭绝（对泥浆输入敏感）以及优势类群的分布或丰度的变化。