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This synthesis is framed within the scope of the Brazilian Benthic Coastal Habitat Monitoring Network (ReBentos WG 4: Mangroves and Salt Marshes), focusing on papers that examine biodiversity-climate interactions as well as human-induced factors including those that decrease systemic resilience. The goal is to assess difficulties related to the detection of climate and early warning signals from monitoring data. We also explored ways to circumvent some of the obstacles identified. Exposure and sensitivity of mangrove and salt marsh species and ecosystems make them extremely vulnerable to environmental impacts and potential indicators of sea level and climate-driven environmental change. However, the interpretation of shifts in mangroves and salt marsh species and systemic attributes must be scrutinized considering local and setting-level energy signature changes; including disturbance regime and local stressors, since these vary widely on a regional scale. The potential for adaptation and survival in response to climate change depends, in addition to the inherent properties of species, on contextual processes at the local, landscape, and regional levels that support resilience. Regardless of stressor type, because of the convergence of social and ecological processes, coastal zones should be targeted for anticipatory action to reduce risks and to integrate these ecosystems into adaptation strategies. Management must be grounded on proactive mitigation and collaborative action based on long-term ecosystem-based studies and well-designed monitoring programs that can 1) provide real-time early warning and 2) close the gap between simple correlations that provide weak inferences and process-based approaches that can yield increasingly reliable attribution and improved levels of anticipation.

Of Brazil’s 7408 km of coastline 6786 km contain mangrove forests, covering some 25,000 km2. Only one coastal state, Rio Grande do Sul, lacks mangrove coverage. Mangroves occur from the border with French Guiana, just above the Equator (04°30′N) to well beyond the Tropic of Capricorn, reaching 28°30′S, near Laguna (Santa Catarina State). Because the term mangrove may be applied to various levels of observation, specifying the proper spacio-temporal scale is important to describe system behavior. In this paper we describe a nested hierarchy of organization levels constituted of patches, stands, settings, coastal segments and large marine ecosystems. Each of these describes an organization that has evolved to facilitate energy dissipation at its relevant scale, and can be related to a geographic unit. We expect that the framework presented here will be useful for the study of mangrove ecosystem health, assessment of ecosystem pathology, and the development of models for the management and conservation of this resource.

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A B S T R A C TSediment cores are an essential tool for the analysis of the dynamics of mangrove succession. Coring was used to correlate changes in depositional environments and lateral sedimentary facies with discrete stages of forest succession at the Cananéia-Iguape Coastal System in southeastern Brazil. A local level successional pattern was examined based on four core series T1) a sediment bank; T2) a smooth cordgrass Spartina alterniflora bank; T3) an active mangrove progradation fringe dominated by Laguncularia racemosa, and; T4) a mature mangrove forest dominated by Avicennia schaueriana. Cores were macroscopically described in terms of color, texture, sedimentary structure and organic components. The base of all cores exhibited a similar pattern suggesting common vertical progressive changes in depositional conditions and subsequent successional colonization pattern throughout the forest. The progradation zone is an exposed bank, colonized by S. alterniflora. L. racemosa, replaces S. alterniflora as progradation takes place. As the substrate consolidates A. schaueriana replaces L. racemosa and attains the greatest structural development in the mature forest. Cores collected within the A. schaueriana dominated stand contained S. alterniflora fragments near the base, confirming that a smooth cordgrass habitat characterized the establishment and early seral stages. Cores provide a reliable approach to describe local-level successional sequences in dynamic settings subject to drivers operating on multiple temporal and spatial scales where spatial heterogeneity can lead to multiple equilibria and where similar successional end-points may be reached through convergent paths. RESUMOTestemunhos de sondagem apresentam-se como importantes ferramentas para análise da dinâmica sucessional de bosques de mangue. A sucessão dos bosques de mangue, no litoral sul do Estado de São Paulo (Brasil), foi determinada com base em quatro testemunhos de sondagem: T1) banco de sedimento; T2) banco de gramínea Spartina alterniflora; T3) bosque de mangue em progradação, dominado por Laguncularia racemosa; e T4) bosque de mangue maduro, dominado por Avicennia schaueriana. Os testemunhos foram descritos macroscopicamente em função de cor, textura, estruturas sedimentares e componentes orgânicos. A base de todos os testemunhos apresentou padrão semelhante, sugerindo colonização similar por bosques de mangue , em toda sua extensão. Áreas em progradação apresentam banco de sedimento exposto, colonizado por S. alterniflora. Faixa de L. racemosa substitui a gramínea, com a progradação. À maior consolidação do sedimento, passam a dominar outras espécies típicas de mangue, como observado no bosque maduro, onde A. schaueriana alcança grande desenvolvimento estrutural. No testemunho coletado na área colonizada pelo bosque maduro dominado por A. shaueriana, há fragmentos de S. alterniflora próximo à base, confirmando o papel da gramínea como espécie pioneira. Os testemunhos analisados refletem a zonação e a sucessão dos bosques de mangue da r...

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