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This study assesses the evolution of major anthropogenic drivers of environmental impacts on Neotropical mangroves, the changes in the environmental pressures acting upon them, and the respective societal responses during the past 40 years. It reviews the impacts of new drivers, in particular those resulting from global climate change and the expansion in aquaculture and the effectiveness of local societal responses aimed at addressing them. Adaptation and mitigation actions are proposed to cope with the impacts and their socio‐economic consequences for Latin America and Caribbean mangroves. By comparing the situation in Latin America and the Caribbean with other regions, the knowledge gaps and priority research needs are discussed to support delineating a preliminary unifying framework to address the environmental pressures affecting mangroves. This scenario necessarily includes the interaction of climate change with human interventions and their effects on ecosystem goods and services, as well as their respective adaptation and management options. Results show that drivers of environmental impacts have changed in the past 40 years, reducing the effectiveness of some important societal responses towards conservation and sustainable management with a great potential to increase rates of mangrove deforestation and conversion to human uses. Although efforts in conservation and restoration have contributed to decreasing pressure on these ecosystems, the coupling of old drivers, such as damming, with climate change, and the appearance of new drivers in the region, such as shrimp aquaculture, may eclipse the gains made through these conservation efforts. Despite the negative trend, we discuss some successful efforts to curb negative impacts of human activities on mangroves. We also recommend regional assessments based on primary sources in the representative mangrove‐bearing countries throughout the continent to allow the upscaling of their experiences towards a regional response to the challenges facing Neotropical mangrove conservation and sustainable use.

Brazilian mangroves cover about 11,100 km2 and provide a wide range of ecosystem services. Despite their importance, they are one of the most impacted ecosystems because of combined influences of climate change, pollution, and direct conversion and loss. A major driver of environmental impacts is shrimp farming and this is particularly acute in the semi-arid northeast of Brazil, where mangroves are constrained in a narrow band along ephemeral estuaries that are often impacted by multi-year droughts. Recent changes to Brazilian law, in particular the Forest Code, have weakened protection for mangroves and associated “apicum” (salt pan) ecosystems. In NE Brazil, most shrimp ponds are converted from mangrove-adjacent “apicuns” rather than the mangroves themselves with periodic hydrological connectivity through dammed channels, allowing the flushing of effluents. As a result, the main impacts on mangroves are typically indirect, because of pollution inputs from shrimp pond effluents and associated loss of ecosystem services including reductions in primary productivity, carbon storage capacity, resilience to other environmental stressors, their efficiency as estuarine filters, and biodiversity and abundance of subsistence use of marine species. Soil damage and infrastructure remaining after shrimp pond deactivation impairs mangrove recovery. This extends the duration of the damage and allows the occupation of degraded areas by other activities that can permanently impair ecosystem function. In this review, we address several aspects of the shrimp culture boom in NE Brazilian, their features and consequences, and the future of mangroves in the region considering climate change and rising poverty. Our conclusions on the practices and outcomes of shrimp farming in mangroves are likely to apply to areas with similar environmental settings, e.g., semiarid regions worldwide, and particularly in the Latin America and Caribbean region, and our findings can be taken into account to improve conservation and management of these forests at the least to a regional scale.

About 120 million people worldwide live within 10 km of large mangrove forests, and many of them directly depend on the goods and services provided by these ecosystems. However, it remains unclear how to synchronize ecological definitions and legal conservation strategies regarding mangroves, especially in developing countries, such as Brazil. The influence of human populations' socio-economic context in mangrove conservation policies, as well associated challenges in incorporating this influence, are underestimated or, often, largely ignored. Considering the recent threats emerging from changes in legislation and the lack of spatial and social-ecological integrated data to plan mangrove conservation in Brazil, this paper aims to answer the following questions: (1) What suitable measures could managers and other decision makers adopt for efficient mangrove conservation planning?; (2) What are the site-specific, social-ecological aspects that need to be taken into account when deciding on conservation and management strategies?; and (3) How could science contribute to the development of these measures? In order to achieve an ecosystem-based management approach, mangrove ecosystems should not be divided into sub-systems, but instead treated as an integrated system. Furthermore, interconnections with other coastal ecosystems must be assessed and taken into account. This is crucial for effective systematic conservation planning. Also, most of the particular social-ecological aspects in the different types of mangrove ecosystems along the Brazilian coast, and how those differences might be considered while planning for conservation, remain poorly understood. Based on similar drivers of change, geological features, and likely impacts of climate change, a macro-unit approach is proposed to group mangrove systems along the Brazilian coast and guide national policies. This paper draws parallels with management approaches worldwide to find common points and hence lessons to be applied in other regional realms. It considers the issues of legal vulnerability and needs for social-ecological data on mangroves, contributing toward systematic conservation planning and ecosystem-based management for these ecosystems.