We aimed to determine the important functional dimensions that may drive forest succession and community assembly patterns in dry tropical forests. We investigated whether there were patterns in specific functional strategies during succession in the dry tropical forests of the Florida Keys, whose unique physical setting includes nutrient‐stressed, salt‐stressed, and water‐limited environments. The study, which focused on ten traits, determined the leading trait dimensions by which species differentiate from one another in the study area. The general patterns of trait covariation at individual sites and among species were analyzed using principal component analysis. Trait niche overlap indices were calculated for all species sampled across all plots. Evidence for/against likely community assembly processes was tested using the coefficient of heterogeneity to determine whether variation within and among five key traits was clustered, random, or evenly distributed across young, old, or all measured forest stands. A combination of plant architecture, wood density, and three leaf traits (specific leaf area, leaf phosphorus, and leaf nitrogen) comprised a key set of functional traits that are important for understanding the community assembly process in dry tropical forest. Older forest stands were dominated by species with low specific area, low leaf nitrogen content, dense wood, and deeper and narrower canopies. Trees of old forests had leaves with lighter carbon isotope composition, suggesting that such individuals were making more efficient use of scarce water. Tests of trait distributions showed significant clustering across forests of all ages. When individual trait distributions in old stands were tested, they displayed either randomly or evenly distributed traits across trait niche space, indicating that resource partitioning was predominant in shaping community composition. Physical traits of trees in young communities are associated with resource acquisitive strategies, while old communities are dominated by species with traits that enhance survival in environments defined by competition or chronic resource scarcity.

Obtaining spatially explicit, cost-effective, and management-relevant data on invasive plant distributions across large natural areas presents considerable challenges. This is especially true when multiple monitoring objectives exist, because the utility of different monitoring methodologies varies with scale, logistical considerations, and information needs. The Florida Everglades is a vast wetland landscape with widespread invasive plant infestations and multiple management jurisdictions. A multi-agency team Working Group conducted a workshop in 2013 to explore opportunities to enhance the performance of a regional weed control program. Among the most important developments occurring at this meeting was the recognition that relevant management questions are scale-dependent. This led the team to define multiple monitoring objectives. Essential for conveying the success of the weed management program is quantifying large-scale patterns of change, as are quantifying fine-scale patterns informing control activities, defining mechanisms of spread, recognizing accelerating rates of spread, and detecting patterns of occupancy immediately before management intervention. The group’s deliberation resulted in the emergence of a multiscale monitoring program utilizing several distinct monitoring protocols, including systematic landscape-level reconnaissance, a sample-based spatially stratified monitoring system, detailed inventories in planned treatment areas, and a set of methods focused solely on early detection and rapid response. Here we provide an overview of the Everglades multiscale invasive plant monitoring program, highlight benefits and challenges of each program component, and discuss how this program has improved regional invasive plant management.

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Ecosystems have been shaped by fire for millions of years. Many oligotrophic ecosystems rely on fire for biogeochemical cycling and maintenance of key processes. However, it is uncertain how fire intensity interacts with nutrient limitation to drive differential responses in postfire biogeochemical cycling and ecosystem recovery. In this study, we compare pre-and postfire carbon and nutrient pools in two adjacent wetlands characterized by either lower or higher phosphorus (P) inputs and thus different levels of P limitation. Carbon (C), nitrogen (N), and P pools and litter and root decomposition rates were measured starting 1 year prefire until 1 year postfire in lower-P (LP) and higher-P (HP) freshwater marshes of the Florida Everglades. Dominant vegetation biomass and vegetation composition were monitored as well. Fire energy release was measured to link the causal mechanism, heat transfer, to nutrient fluxes. We observed temporary increases in surface water, periphyton, and leaf tissue P concentrations in both wetland types following fire. Soil P increased and soil C:P and N:P ratios decreased postfire in the LP wetland but did not change in the HP wetland. Prefire soil P was greater in the HP than the LP wetland, but did not differ 1 month or 1 year postfire. Vegetation structure and composition were marginally affected by fire. Fire intensity was highly