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Analysis of lignin in seawater is essential to understanding the fate of terrestrial dissolved organic matter (DOM) in the ocean and its role in the carbon cycle. Lignin is typically quantified by gas or liquid chromatography, coupled with mass spectrometry (GC‐MS or LC‐MS). MS instrumentation can be relatively expensive to purchase and maintain. Here we present an improved approach for quantification of lignin phenols using LC and absorbance detection. The approach applies a modified version of parallel factor analysis (PARAFAC2) to 2^ndderivative absorbance chromatograms. It is capable of isolating individual elution profiles of analytes despite co‐elution and overall improves sensitivity and specificity, compared to manual integration methods. For most lignin phenols, detection limits below 5 nmol L⁻¹were achieved, which is comparable to MS detection. The reproducibility across all laboratory stages for our reference material showed a relative standard deviation between 1.47% and 16.84% for all 11 lignin phenols. Changing the amount of DOM in the reaction vessel for the oxidation (dissolved organic carbon between 22 and 367 mmol L⁻¹), did not significantly affect the final lignin phenol composition. The new method was applied to seawater samples from the Kattegat and Davis Strait. The total concentration of dissolved lignin phenols measured in the two areas was between 4.3–10.1 and 2.1–3.2 nmol L⁻¹, respectively, which is within the range found by other studies. Comparison with a different oxidation approach and detection method (GC‐MS) gave similar results and underline the potential of LC and absorbance detection for analysis of dissolved lignin with our proposed method.

The potential for animals to modify spatial patterns of nutrient limitation for autotrophs and habitat availability for other members of their communities is increasingly recognized. However, net trophic effects of consumers acting as ecosystem engineers remain poorly known. The American AlligatorAlligator mississippiensisis an abundant predator capable of dramatic modifications of physical habitat through the creation and maintenance of pond‐like basins, but its role in influencing community structure and nutrient dynamics is less appreciated.

The relationship between biodiversity and stability, or its inverse, temporal variability, is multidimensional and complex. Temporal variability in aggregate properties, like total biomass or abundance, is typically lower in communities with higher species diversity (i.e., the diversity–stability relationship [DSR]). At broader spatial extents, regional‐scale aggregate variability is also lower with higher regional diversity (in plant systems) and with lower spatial synchrony. However, focusing exclusively on aggregate properties of communities may overlook potentially destabilizing compositional shifts. It is not yet clear how diversity is related to different components of variability across spatial scales, nor whether regional DSRs emerge across a broad range of organisms and ecosystem types. To test these questions, we compiled a large collection of long‐term metacommunity data spanning a wide range of taxonomic groups (e.g., birds, fish, plants, invertebrates) and ecosystem types (e.g., deserts, forests, oceans). We applied a newly developed quantitative framework for jointly analyzing aggregate and compositional variability across scales. We quantified DSRs for composition and aggregate variability in local communities and metacommunities. At the local scale, more diverse communities were less variable, but this effect was stronger for aggregate than compositional properties. We found no stabilizing effect of γ‐diversity on metacommunity variability, but β‐diversity played a strong role in reducing compositional spatial synchrony, which reduced regional variability. Spatial synchrony differed among taxa, suggesting differences in stabilization by spatial processes. However, metacommunity variability was more strongly driven by local variability than by spatial synchrony. Across a broader range of taxa, our results suggest that high γ‐diversity does not consistently stabilize aggregate properties at regional scales without sufficient spatial β‐diversity to reduce spatial synchrony.

Macrophyte foundation species provide both habitat structure and primary production, and loss of these habitats can alter species interactions and lead to changes in energy flow in food webs. Extensive seagrass meadows in Florida Bay have recently experienced a widespread loss of seagrass habitat due to a Thalassia testudinum mass mortality event in 2015 associated with prolonged hypersalinity and bottom-water anoxia. Using stable isotope analysis paired with Bayesian mixing models, we investigated the basal resource use of seven species of seagrass-associated consumers across Florida Bay in areas affected by the 2015 seagrass die-off. Three years after the die-off, basal resource use did not differ for species collected inside and outside the die-off affected areas. Instead, consumers showed seasonal patterns in basal resource use with seagrass the most important in the wet season (58%), while epiphytes were the most important in the dry season (44%). Additionally, intraspecific spatial variability in resource use was lower in the wet season compared to the dry season. We were unable to detect a legacy effect of a major disturbance on the basal resource use of the most common seagrass-associated consumers in Florida Bay.

Energetic resources and habitat distribution are inherently linked. Energetic resource availability is a major driver of the distribution of consumers, but estimating how much specific habitats contribute to the energetic resource needs of a consumer can be problematic.

Mangroves buffer inland ecosystems from hurricane winds and storm surge. However, their ability to withstand harsh cyclone conditions depends on plant resilience traits and geomorphology. Using airborne lidar and satellite imagery collected before and after Hurricane Irma, we estimated that 62% of mangroves in southwest Florida suffered canopy damage, with largest impacts in tall forests (>10 m). Mangroves on well-drained sites (83%) resprouted new leaves within one year after the storm. By contrast, in poorly-drained inland sites, we detected one of the largest mangrove diebacks on record (10,760 ha), triggered by Irma. We found evidence that the combination of low elevation (median = 9.4 cm asl), storm surge water levels (>1.4 m above the ground surface), and hydrologic isolation drove coastal forest vulnerability and were independent of tree height or wind exposure. Our results indicated that storm surge and ponding caused dieback, not wind. Tidal restoration and hydrologic management in these vulnerable, low-lying coastal areas can reduce mangrove mortality and improve resilience to future cyclones.

In aquatic systems, refuge habitats increase resistance to drying events and maintain populations in disturbed environments. However, reduced water availability and altered flow regimes threaten the function of these habitats. We conducted a capture–mark–recapture study, integrating angler citizen science. Our objectives were to quantify variation in survival of Florida Largemouth BassMicropterus salmoides floridanusin a coastal refuge habitat across seasonal hydrological periods and over 4 years of varying drying severity and to determine the contribution of angler sampling to improving capture probabilities. Apparent survival of Florida Largemouth Bass in the coastal Everglades was highest in wet and drying periods and lowest in dry and reflooding periods. Interannual survival was closely tied to the length of upstream marsh drying, with the lowest observed survival (0.21) during a drought year. The inclusion of angler sampling improved recapture probabilities, suggesting that angler data can supplement standardized electrofishing sampling. Findings show that during short drying events Florida Largemouth Bass survival can be relatively high, with implications for Everglades restoration. Understanding the ability of refuge habitats to buffer populations from drying disturbance is a key component for conservation and restoration, particularly under climate change scenarios.

Mangroves are the most blue-carbon rich coastal wetlands contributing to the reduction of atmospheric CO₂through photosynthesis (sequestration) and high soil organic carbon (C) storage. Globally, mangroves are increasingly impacted by human and natural disturbances under climate warming, including pervasive pulsing tropical cyclones. However, there is limited information assessing cyclone’s functional role in regulating wetlands carbon cycling from annual to decadal scales. Here we show how cyclones with a wide range of integrated kinetic energy (IKE) impact C fluxes in the Everglades, a neotropical region with high cyclone landing frequency. Using long-term mangrove Net Primary Productivity (Litterfall, NPP_L) data (2001–2018), we estimated cyclone-induced litterfall particulate organic C (litter-POC) export from mangroves to estuarine waters. Our analysis revealed that this lateral litter-POC flux (71–205 g C m⁻² year⁻¹)—currently unaccounted in global C budgets—is similar to C burial rates (69–157 g C m⁻² year⁻¹) and dissolved inorganic carbon (DIC, 61–229 g C m⁻² year⁻¹) export. We proposed a statistical model (PULITER) between IKE-based pulse index and NPP_Lto determine cyclone’s impact on mangrove role as C sink or source. Including the cyclone’s functional role in regulating mangrove C fluxes is critical to developing local and regional climate change mitigation plans.