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Tropical cyclones play an increasingly important role in shaping ecosystems. Understanding and generalizing their responses is challenging because of meteorological variability among storms and its interaction with ecosystems. We present a research framework designed to compare tropical cyclone effects within and across ecosystems that: a) uses a disaggregating approach that measures the responses of individual ecosystem components, b) links the response of ecosystem components at fine temporal scales to meteorology and antecedent conditions, and c) examines responses of ecosystem using a resistance–resilience perspective by quantifying the magnitude of change and recovery time. We demonstrate the utility of the framework using three examples of ecosystem response: gross primary productivity, stream biogeochemical export, and organismal abundances. Finally, we present the case for a network of sentinel sites with consistent monitoring to measure and compare ecosystem responses to cyclones across the United States, which could help improve coastal ecosystem resilience.

Aim The aim was to quantify the influence of urban land use and urban populations on mangrove systems around the world over the past four decades. Location Global. Time period 1997–2015. Major taxa studied Avicennia, Laguncularia, Rhizophora, Aves, Actinopterygii, Crustacea and Mollusca. Methods This review extracts results of mangrove studies on forest cover and structure, nutrient dynamics, sediment contamination and faunal community assemblages conducted around the world between 1997 and 2015. These observations are then correlated with surrounding social–ecological spatial characteristics pertaining to urbanization. Results Mangrove coverage in large cities is mostly decreasing, and at a greater rate than means for corresponding countries. Both expanding urbanization and existing agriculture are most strongly correlated with mangrove losses, which are primarily occurring 5–10 km from urban areas. Along a gradient of surrounding urban land use, mangrove leaf δ15N content increases, and leaf carbon to nitrogen ratios decrease. Sediment concentrations of almost all examined heavy metals are strongly and positively correlated with both surrounding urban and mangrove extent. The diversity of subsistence fisheries increases significantly with surrounding mangrove extent. Worm diversity decreases with increasing surrounding urbanness (urban index), and mangrove specialist bird diversity increases with increasing surrounding urban coverage as well as with mangrove coverage. Main conclusions Mangroves increasingly coexist within highly anthropogenic landscapes along urbanized coasts. Most ecological reports of these systems, however, lack quantified representations of the urban landscape, such as population density or impervious surface coverage. The results of this analysis suggest that some of the reported patterns of forest coverage, nitrogen dynamics, heavy metal contamination and faunal community assemblages in isolated urban mangroves are systemic across the world. These findings are particularly pertinent to 21st century tropical coastlines, which will see some of the greatest urbanization rates over the next century and will guide urban mangrove ecology towards the development of more synergistic social–ecological systems.

Although hydrology and water chemistry are known to change in proximity to cities, there remains little empirical evidence connecting specific components of urban landscapes to mangrove flooding dynamics or surface water chemistry. This study constructs five-year water level models from tidal harmonics and precipitation inputs to characterize mangrove flooding across urban gradients in three watersheds of Puerto Rico. There was some evidence for an influence of urbanization on both flooding and water chemistry, but this depended on the definition of urbanness, and points instead to geomorphology as the primary culprit. Urban sites exhibited 46% longer hydroperiods and 450% lower depths than non-urban sites. Rainfall importance was explained more by geomorphology than by urbanization and suggested systems with limited tidal connectivity are four times more sensitive to rainfall than systems with full tidal connectivity. There was also evidence for changes in tidal amplitudes along the urban gradient, which may explain the observed differences in flooding. Relationships between surface water chemical metrics and land cover contradicted previous studies by suggesting lower nutrients and biochemical oxygen demand with increasing urbanization. These results reinforce the understanding that the most important drivers of urban mangrove hydrology and water quality in Puerto Rico are likely geomorphology and tidal connectivity, with little but not zero influence from surrounding land cover. Results should be considered alongside the reported errors stemming from inaccuracies in digital elevation and rainfall response models, and will be useful in understanding future ecological censuses on the island.

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Tropical cyclones drive coastal ecosystem dynamics, and their frequency, intensity, and spatial distribution are predicted to shift with climate change. Patterns of resistance and resilience were synthesized for 4138 ecosystem time series from n = 26 storms occurring between 1985 and 2018 in the Northern Hemisphere to predict how coastal ecosystems will respond to future disturbance regimes. Data were grouped by ecosystems (fresh water, salt water, terrestrial, and wetland) and response categories (biogeochemistry, hydrography, mobile biota, sedentary fauna, and vascular plants). We observed a repeated pattern of trade-offs between resistance and resilience across analyses. These patterns are likely the outcomes of evolutionary adaptation, they conform to disturbance theories, and they indicate that consistent rules may govern ecosystem susceptibility to tropical cyclones.

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