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Geographically isolated wetlands (GIWs) play a critical role in regional hydrology, streamflow, groundwater recharge, evapotranspiration, and water quality. Despite their importance, research on quantifying discharges from these wetlands remains scarce. This study focuses on the hydrological characterization of GIWs in W-C Florida, a region where they cover a significant proportion of the land surface. The paper introduces a new procedure for developing Stage–Storage–Discharge (rating) characteristics essential for deterministic hydrological modeling in larger geographic areas. The approach synthesizes and extends previous research methodologies and offers simplified key modeling coefficients (m and n), which act as intelligent calibration knobs. These coefficients, when coupled with easily derivable physical attributes such as areas, slopes, and elevations, allow for the accurate simulation of downstream discharge timings and magnitudes, including flood behavior. The proposed method was tested using observational data from well-calibrated models. The results indicated a relative error of −7.2% for stage–storage and 15% for stage–discharge. GIS-based techniques were evaluated against surveyed data, and the results showed an accuracy of 0.16 m (0.52 ft) in estimating both the invert elevation and the maximum depth of GIWs. This effort will ultimately contribute to a better understanding and management of these critical ecosystems. [ABSTRACT FROM AUTHOR]

This paper reviews some of the key influences that wetlands have had on the development of human society together with the history of wetland use, conservation and management in the context of changing human interactions from prehistoric to modern times. It documents the origins of the Ramsar Convention and the changes in the criteria for defining wetlands of international importance from an emphasis on migratory birds to those of wider functional importance contributing to community well-being. This led to a significant increase in the number of signatories from developing countries The change in scientific emphasis from ecology to ecosystems (and ecosystem services) is identified as a key element of the wetland paradigm shift, which has occurred in the last half century and renewed the recognition of the importance of the natural capital of wetlands. It represents a change in research agenda from what wetlands are to what wetlands do. Modification of the Ramsar wise use concept is documented, and evolution of wetland assessment methods is traced in relation to policy development and the need for a strong science evidence base to improve decision-making connected with wetland conservation and management. The author also addresses the significance of wetland economic valuation and biodiversity issues, transboundary water management with particular reference to the marshlands of Mesopotamia (southern Iraq), conflict, and human livelihood issues. Examples are given of the drive towards wetland restoration in different countries, and at different scales, with awareness of the extraordinarily high costs associated with major schemes such as the Florida Everglades which may prohibit replication in other parts of the world. Adoption of the Ecosystem Approach and the "Wholescapes" concept are seen as important in the future management of wetland ecosystems. The wide-ranging interactions within the structure of a new wetland paradigm are summarized diagrammatically. An examination of current societal priorities and challenges resulting from the nexus of issues arising from food production, energy, water, and environmental change and health suggests both significant threats to wetlands, but also some opportunities for these ecosystems to play a part in sustainable solutions contributing to human well-being. The paper concludes with an endorsement of a new World Charter for wetlands but emphasizes the vital importance of partnership working and the key engagement of local communities to make any new initiative for enhanced protection and management of wetlands to work on the ground. Key challenges facing wetland science are identified, but it is the realization that healthy wetland ecosystems are a significant contributor to human and societal well-being that underpins the paradigm shift in research, management and policy needs. [ABSTRACT FROM AUTHOR]

Much of Florida's economy is tied to the third-largest barrier reef in the world, the Florida Reef Tract. However, because of anthropogenic threats, it is not the thriving ecosystem it once was, and its persistence requires new, unconventional management strategies. Two entities have emerged to address this problem: the Florida Keys National Marine Sanctuary, a formally structured regulatory authority, and the Southeast Florida Coral Reef Initiative, an informal network of stakeholder partnerships. We therefore ask: How does coral reef management vary over the different spatial extents and structures of these organizations, and how do these organizations vary in incorporating important aspects of novel ecosystem management? Using 1122 statements from news documents, public meeting transcripts, and stakeholder interviews, we compare the institutional elements of each organization and determine the importance they place on five management considerations. Our results indicate significant institutional differences between the two, one marked by a focus on regulations and authority and the other by a focus on data collection and preparedness. Understanding these institutional differences promotes a better understanding of how adaptive governance can be iteratively applied in novel ecosystems to improve management under rapidly changing conditions. • Anthropogenic threats have damaged the Florida Reef Tract, forming a novel ecosystem. • A Novel Ecosystems Framework is used to compare two management systems. • Two types of institutions, formal and informal, appear via case study analysis. • This research identifies where formal-informal cooperation can improve management. • This new understanding improves reef management and benefits coral reefs worldwide. [ABSTRACT FROM AUTHOR]

Aims: The stress gradient hypothesis predicts that competition will be important in productive environments while facilitation will be common in environments with high stress or consumer pressure. However, abiotic stress and grazing may vary independently and even occur simultaneously. Here we examine the outcome of plant interactions in grazed wetlands where consumer pressure and abiotic stress occur concurrently. We hypothesized that cattle grazing and microhabitat would alter the outcome of plant interactions. Given that wetland edges are drier and less productive than wetland centers we expected that facilitation would be greatest in drier wetland edges due to greater abiotic stress regardless of cattle presence. Location: Archbold Biological Station's Buck Island Ranch (BIR), south‐central Florida, USA (27°09′ N, 81°11′ W). Methods: We conducted an experiment for two growing seasons in ten wetlands, five exposed to cattle grazing and five fenced. Two wetland obligate plants were included (Panicum hemitomon and Alternanthera philoxeroides), and plots were assigned to three treatments (a) all neighbors removed; (b) all neighbors removed except Juncus effusus, a dominant, unpalatable plant; and (c) all neighbors intact (control), in both wetland centers and edges. Differences in survival, change in height and number of leaves were assessed. Results: In ungrazed wetlands, plant survival was higher in wetland edges vs centers, while it did not differ between microhabitats in grazed wetlands. Survival in wetland edges was further increased by the presence of Juncus effusus. Positive interactions under grazed conditions were clear when plant height was assessed, but negative interactions affected leaf production in both ungrazed and grazed wetlands. Conclusions: Grazing interacts with wetland microhabitat to alter plant survival. Facilitative interactions on plant height were apparent in grazed wetlands. Understanding how plant interactions change under different biotic and abiotic contexts is important for informing ecosystem restoration and management. [ABSTRACT FROM AUTHOR]

Human activities very obviously impact the environment. From pollution, to deforestation, to the introduction of invasive species, human activities often cause noticeable effects within an ecosystem. Knowledge of the cause and effect relationship between an action and its consequences makes up the bulk of effects pathways management. Describing land development proposals using data concerning Effects Pathways is often employed to minimize the harmful effects of developing that land. This data includes a list of the activities involved, the kinds of cause-and-effect interactions that are known to exist, and the methods by which stressors finally result in consequences in the environment. This study aims to uncover and catalog the resource needs for every life stage of 64 imperiled plant species, some of them being endemic to the state of Florida. This data could then be used to identify cause-and effect relationships between Human actions and the wellbeing of these endangered species. Most data collected was obtained by way of ECOS, most notably through the use of the "Five-year review" papers when they were available. Additional data was collected through the use of various peer-reviewed articles. Raw data in the form of papers, articles, and reports were mostly processed visually and the pertinent data from the raw data was recorded manually. This was done through careful reading and note-taking. The resource needs and life stage data was then added into a spreadsheet where data for each plant was recorded. From the data collected from the life stages and resource needs of the plant species used in this study several trends between the species involved arose. These trends Include low genetic diversity, persisting only in habitats exclusive to Florida, poor defenses against competing or invasive species, and benefitting from regular wildfires. The information gathered in this study is sure to be instrumental in allowing the effects pathways management team of the USFWS to effectively and efficiently manage and maintain Florida's ecosystems through understanding of their life cycles, resource needs, and the effects that certain actions or inactions from humans cause on them. This information allows us to understand not only the relationship between humans and the ecosystem, but the relationships between the organisms that live in them as well. There are several instances in which one plant on the list often lives near or relies on another plant from the list for its survival. This shows that the act of protecting one species is often the same as acting to protect the other species that rely upon it. This holistic approach to ecosystem management via the protection of one species that benefits several others can be very effective in ensuring the survival of several uniquely Floridian ecosystems. [ABSTRACT FROM AUTHOR]

Exotic invasive species are one of the most widespread and common agents of change in ecosystems worldwide. Here, we are focused on community-level changes associated with the appearance and persistence of exotic species in an ecosystem over more than 2 decades. We combined datasets of Florida's ant (Hymenoptera: Formicidae) community from Wekiwa Springs State Park, Florida, USA, spanning 25 yr, which included 3 sampling events in several distinct upland ecosystems. Species accumulation curves, non-parametric species estimators, community similarity indices, and ratios of exotic to native ants were used to assess sampling effort, including patterns of diversity, and changes in community composition. Our data showed that the ant community of Wekiwa Springs has at least 4 exotic species present in all of the ecosystems sampled within the park. These upland ecosystems are accumulating exotics slowly and, with one exception, there is no clear signal that the exotic species are displacing native species. The likely exception is the invasive fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), causing local extinction of the native fire ant Solenopsis geminata (Fabricius) (Hymenoptera: Formicidae). Continued long-term monitoring efforts are necessary to understand how these exotics may impact native communities in the future. [ABSTRACT FROM AUTHOR]

Understanding the effects of hurricanes and other large storms on ecological communities and the post-event recovery in these communities can guide management and ecosystem restoration. This is particularly important for communities impacted by invasive species, as the hurricane may affect control efforts. Here we consider the effect of a hurricane on tree communities in southern Florida that has been invaded by Melaleuca quinquevervia (melaleuca), an invasive Australian tree. Biological control agents were introduced starting in the 1990s and are reducing melaleuca in habitats where they are established. We used size-structured matrix modeling as a tool to project the continued possible additional effects of a hurricane on a pure stand of melaleuca that already had some level of biological control. The model results indicate that biological control could suppress or eliminate melaleuca within decades. A hurricane that does severe damage to the stand may accelerate the trend toward elimination of melaleuca with both strong and moderate biological control. However, if the biological control is weak, the stand is resilient to all but extremely severe hurricane damage. Although only a pure melaleuca stand was simulated in this study, other plants, such as natives, are likely to accelerate the decline of melaleuca due to competition. Our model provides a new tool to simulate post-hurricanes effect on invasive species and highlights the essential role that biological control has played on invasive species management. [ABSTRACT FROM AUTHOR]

Conservation and management of coastal ecosystems require an understanding of how accelerated sea-level rise (SLR) and altered hydrology impact community shifts over time. This study evaluates the response of tidal wetlands of the Ten Thousand Islands, Collier County, Florida, to SLR and water management, with a focus on the development and distribution of tidal ponds across a wetland landscape. Sediment cores collected from marshes, mangroves, and tidal ponds reveal a clear transgressive stratigraphy. Facies analyses demonstrate that ponds originate from the surface downward through the degradation of marsh peat. Analyses of 1953 and 2009 aerial imagery using ArcGIS® software clearly identified tidal pond initiation, growth, and merger over time. Wetlands west of the Faka Union Canal, which have limited freshwater sheet flow due to canalization, are experiencing a greater increase in pond count, pond density (p = 0.0038), and mean pond area (p < 0.0001). Qualitative observations also recognize a relatively larger influence of mangrove envelopment over time in western sites compared with those retaining near-natural flows. Future land management plans must account for the expected submergence of inland marsh ecosystems driven by SLR and accelerated by hydrologic alteration. Continued restoration of freshwater sheet flow is necessary for slowing the regional transition (and loss) of graminoid marshes to either mangrove or pond environments. Without such action, a complete loss of these biologically diverse marsh ecosystems as mangrove forests encroach and marsh surfaces submerge is probable in the short term. [ABSTRACT FROM AUTHOR]

Within the environment of semitropical central Florida emerges a confluence of two management needs between sand pine (Pinus clausa) and the Florida scrub-jay (Aphelocoma coerulescens). Each is a unique species adapted to extremely xeric scrub sites and commonly found on the Ocala National Forest. Since the 1940s, sand pine has been successfully regenerated after timber harvest within the constraints of managing for a low-value product on a poor site. In 1987, the Florida scrub-jay was designated federally threatened, and a recovery plan was developed in 1990 by the US Fish and Wildlife Service (USFWS). Managers on the Ocala National Forest began to adapt sand pine management to accommodate habitat needs of the Florida scrub-jay. In recent years, scrub-jay habitat statewide has declined further and as the USFWS develops a revision to the 1990 Recovery Plan, National Forest managers are evaluating new management schemes to best provide scrub-jay habitat yet still manage sand pine. Management and Policy Implications Collaboration between resource managers was a key element in developing a management plan that has multiple resource objectives and treatments. In this case, resource managers representing wildlife biology, fire management, timber management, and silviculture were the interdisciplinary team that developed the new management plan. Understanding the past resource management history of the ONF was important in developing a new plan so that successful activities and treatments were retained in the new plan and unsuccessful activities and treatments were not repeated. By informing and consulting with the public all along the way to project development, the final plan was better accepted and fewer negative comments during the formal public involvement process were received. Federal and state biologists monitored scrub-jay populations beginning shortly after the species was federally listed as threatened in 1987 and provided important data to evaluate past treatments and propose new ones. In the past, resource managers developed one timber management plan that attempted to modify treatments and techniques to provide habitat needs for multiple species. However, as we honestly evaluated the current needs of Florida scrub-jays and the effects on habitat from past timber management, we needed to separate the management plan into different areas to best manage for scrub-jays. [ABSTRACT FROM AUTHOR]

• Longleaf pine stand structure varies by community, but growth rates do not. • Longleaf pine stand structure is correlated with fire and species composition. • Growth rates increase with temperature, but decrease with less precipitation. • Managers should use fire to support species that facilitate longleaf establishment. The longleaf pine (Pinus palustris) savanna is an endangered ecosystem within a global biodiversity hotspot. However, most studies of longleaf habitats have not considered their distinct structure and function among unique communities, which are critical for developing appropriate management strategies. We aim to assess how differences in climate, fire, and species composition interact and relate to longleaf pine densities and growth rates in distinct communities. We surveyed longleaf pine stand structure (density by size and age classes) and estimated growth rates using 516 tree cores across 5 community types (69 plots, each ≤ 160 m2). Surveys covered the range of longleaf pine in Florida, USA, including the southernmost extent of the species range, and included all communities where longleaf are dominant (sandhill, upland pine, and mesic, wet, and scrubby flatwoods). We used an NMDS ordination to classify communities by species composition. We used linear mixed-effects models to examine the effect of community type on longleaf pine density and growth rates and then used recursive partitioning and regression tree analyses to identify how climate, fire, and species composition affect density and growth rates. We found that stand structure and species composition were different across communities, with upland pine being the most species rich and having the highest density of mature trees, whereas growth rates were not statistically different across communities. Across communities, unique interactions between climate, fire, and species composition, resulted in differences in stand structure and growth rates. In general, tree and grass stage densities were best predicted by species composition and fire rather than by climate, whereas growth rates were best predicted by climate. Having included the southernmost extent of longleafs range we show that longleaf growth rates increased with higher temperatures, but this effect is reversed in dry conditions. Our results suggest that longleaf growth rates across its range will be more sensitive to current and future climate change than longleaf population density. Furthermore, while controlling competition from hardwoods has been a focus of longleaf restoration, our results suggest that species that facilitate longleaf establishment may be equally important in restoring and managing these habitats. Managers should design and apply regional and community specific plans that take into account relationships between fire and associated species composition under a changing climate, which will influence strand structure and tree growth differently in different communities. [ABSTRACT FROM AUTHOR]

The Southeast Florida Regional Climate Change Compact (SFRCCC) has been highlighted as a regional climate change governance exemplar for land use planning. After six years, we find the compact has given momentum to local climate change planning through the Regional Climate Action Plan and provides a foundation for adaptive governance for climate change adaptation. We also find aspects of the compact lacking in terms of representation, decision making, learning, and problem responsiveness. Efforts are now needed to scale down implementation and scale up governance and planning more systematically to address climate change adaptation needs at multiple levels. [ABSTRACT FROM AUTHOR]

Resource managers in South Florida are aware that coastal and marine ecosystems provide food, recreation, and a quality of life that are highly-valued by humans. Estimates of economic values in Florida, such as willingness-to-pay for a day of coral reef snorkeling or the change in this value from a change in coral cover, are not updated in a timely manner or are not available at all. Usually these studies are "baseline studies" that provide a snapshot of economic values under existing economic and environmental conditions. Therefore, to be useful to ecosystems management, human dimension (HD) economic indicators that are relatively easy to measure each year must be identified. In addition, they must be combined with a conceptual model that links these indicators to the ecosystem services; their relevant economic values; the HD non-economic metrics of well-being; and the quality and/or quantity of the environmental and ecologic attributes associated with the ecosystem service. Carefully selected HD economic indicators together with ecological, environmental, and non-economic human dimensions indicators can provide a rich source of information for managing the long term conservation and use of coastal and marine ecosystems. In this paper, we specify criteria for selecting HD economic indicators that measure the change in demand for ecosystem services resulting from changes in the quality or quantity of the environmental attributes that comprise the service. We assessed a suite of candidate metrics and arrived at a final set of HD economic indicators for further evaluation. These HD economic indicators are the percentage change from year to year in: (1) coastal park visitation; (2) number of registered recreational boats; (3) pounds of commercial seafood landed; (4) number of live marine organisms landed; and (5) dollar value of insured flood damage claims paid. We illustrated the use of these HD economic indicators with an empirical example for the Florida Keys and Dry Tortugas where the indicators are measured over a one year period. The changes were then scored and the scores were assigned a stop light rating of: green for good (or increasing), yellow for fair (or stable), and red for poor (or decreasing). Our empirical illustration of HD economic indicators offers a first step in developing metrics to rate the status of Florida's coastal and marine ecosystem services. The next steps are to propose a full suite of candidate HD economic indicators and metrics; final selection of HD economic indicators and their integration into the conceptual model; annual calculation of these indicators and their evaluation; and environmental/ecosystem assessment. [ABSTRACT FROM AUTHOR]

Marine ecosystem based management plans are gaining popularity with natural resource managers, but examples of their successful implementation remain few. The complexity inherent in marine ecosystems presents a major obstacle to understanding how individual ecosystem pressures impact multiple ecosystem states that in turn impact the provisioning of ecosystem services. To create and implement successful ecosystem based management plans will require tools for understanding these processes. Over the past three years integrated conceptual ecosystem models of the coastal marine environment have been developed as part of the Marine and Estuarine Goal Setting for South Florida (MARES) project. Here we use these conceptual models in conjunction with a modified DPSIR model, expert opinion and matrix-based analyses to explore the direct and indirect relative impact of 12 ecosystem pressures on 11 ecosystem states and 11 ecosystem services identified through MARES. Within the South Florida coastal ecosystem the most pervasive pressures were freshwater delivery, temperature effects of climate change, and impacts of climate change on weather. For the study region the least pervasive pressures were recreational fishing, commercial fishing, and invasive species. The most at risk ecosystem states, as determined by cumulative impacts were fish and shellfish, protected species, and marine birds. By the same measure, the least at risk states were oyster reefs and inshore flats. The most at risk ecosystem services were existence of a natural system, pristine wilderness experience, and non-extractive recreation. The least impacted ecosystem services were commercial extraction, recreational fishing and climate stability. When the relative direct and indirect (i.e. including state to state interactions) impacts of ecosystem pressures were traced to individual ecosystem services, it was apparent that within the study domain a lack of freshwater delivery to coastal estuaries was the predominant pressure, and recreational fishing had the lowest relative impact on the provisioning of ecosystem services. Through this expert opinion analysis and exploration of the interaction strength among various ecosystem pressures, states, and ecosystem services, we can begin to understand the diverse manners in which ecosystem services are impacted by various pressures. In so doing we provide a tool for resource managers to understand the trade-offs among individual user groups and the possible impact on provisioning of ecosystem services that may occur when considering various management strategies. [ABSTRACT FROM AUTHOR]

We propose a framework for lake management that accounts for inherent variation in ecosystem state and extends the Hutchinsonian niche concept to the ecosystem level. Analogous to the n-dimensional species niche, the ecosystem state “niche” is enclosed by the range of variation in primary environmental drivers within which the target ecosystem state can be established and maintained. We applied this concept to Lake Apopka in central Florida using the 3 major drivers of trophic status: (1) concentration of total phosphorus ([P]); (2) concentration of chlorophylla([Chl-a]); and 3) transparency, as represented by Secchi disk transparency (SDT). We delineated 3 volumes or domains: regional, reference, and target domain, which is the ecosystem state niche for the desired condition. The regional domain includes the range of variation in trophic status drivers for the region. The reference domain lies within the regional domain and includes the ranges for trophic status variables for a set of lakes within the region that have conditions approximating the desired condition. The target domain is the ecosystem state niche, encompassed by the ranges of values required for establishment and persistence of the desired condition. The target domain, or ecosystem state niche, considers site-specific aspects such as the lake's bathymetry, water budget, and natural nutrient loadings. Further, we demonstrate that state diagrams of the temporal trajectory of lake trophic status, plotted over the suite of domains, effectively track progress toward the management goals embodied by the ecosystem state niche. [ABSTRACT FROM AUTHOR]

From 2004 to 2008, 1,834 Environmental Resource Permits were issued for development projects in coastal wetlands within the Charlotte Harbor National Estuary Program. We evaluated 118 sites utilizing three wetland functional assessment methods (WFAMs): Hydrogeomorphic Method (HGM), Wetland Rapid Assessment Procedure (WRAP), and Uniform Mitigation Assessment Method (UMAM). All functioned as designed and produced similar assessments of wetlands but yielded different mitigation results. The study results showed that HGM was most effective in identifying and quantifying wetland functions of coastal wetlands. UMAM and WRAP are useful but delivered mitigation ratios less than one in both function and area, resulting in net wetland losses. The wetland area lost over the study period was small relative to total wetland area, but the permitted wetland elimination is gradually reducing the extent of wetlands. The process relocates wetland functions out of impacted watersheds toward off-site mitigation areas. The WFAM site evaluations indicated an equal or greater balance of ecosystem functions within the total service area when utilizing off-site mitigation. However, there is loss of wetland area and function in the donor watershed and an increase in function, but not area, of wetlands in the receiving watershed. [ABSTRACT FROM AUTHOR]

Precipitation and temperature in Florida responds to climate teleconnections from both the Pacific and Atlantic regions. In this region south of Lake Okeechobee, encompassing NWS Climate Divisions 5, 6, and 7, modern movement of surface waters are managed by the South Florida Water Management District and the US Army Corps of Engineers for flood control, water supply, and Everglades restoration within the constraints of the climatic variability of precipitation and evaporation. Despite relatively narrow, low-relief, but multi-purposed land separating the Atlantic Ocean from the Gulf of Mexico, South Florida has patterns of precipitation and temperature that vary substantially on spatial scales of 10-10 km. Here we explore statistically significant linkages to precipitation and temperature that vary seasonally and over small spatial scales with El Niño-Southern Oscillation (ENSO), the Atlantic Multidecadal Oscillation (AMO), and the Pacific Decadal Oscillation (PDO). Over the period from 1952 to 2005, ENSO teleconnections exhibited the strongest influence on seasonal precipitation. The Multivariate ENSO Index was positively correlated with winter (dry season) precipitation and explained up to 34 % of dry season precipitation variability along the southwest Florida coast. The AMO was the most influential of these teleconnections during the summer (wet season), with significant positive correlations to South Florida precipitation. These relationships with modern climate parameters have implications for paleoclimatological and paleoecological reconstructions, and future climate predictions from the Greater Everglades system. [ABSTRACT FROM AUTHOR]

The ability to document the frequency, extent, and severity of fires in wetlands, as well as the dynamics of post-fire wetland land cover, informs fire and wetland science, resource management, and ecosystem protection. Available information on Everglades burn history has been based on field data collection methods that evolved through time and differ by land management unit. Our objectives were to (1) design and test broadly applicable and repeatable metrics of not only fire scar delineation but also post-fire land cover dynamics through exhaustive use of the Landsat satellite data archives, and then (2) explore how those metrics relate to various hydrologic and anthropogenic factors that may influence post-fire land cover dynamics. Visual interpretation of every Landsat scene collected over the study region during the study time frame produced a new, detailed database of burn scars greater than 1.6 ha in size in the Water Conservation Areas and post-fire land cover dynamics for Everglades National Park fires greater than 1.6 ha in area. Median burn areas were compared across several landscape units of the Greater Everglades and found to differ as a function of administrative unit and fire history. Some burned areas transitioned to open water, exhibiting water depths and dynamics that support transition mechanisms proposed in the literature. Classification tree techniques showed that time to green-up and return to pre-burn character were largely explained by fire management practices and hydrology. Broadly applicable as they use data from the global, nearly 30-year-old Landsat archive, these methods for documenting wetland burn extent and post-fire land cover change enable cost-effective collection of new data on wetland fire ecology and independent assessment of fire management practice effectiveness. [ABSTRACT FROM AUTHOR]

We developed a conceptual successional model for South Florida that describes relationships among major natural plant communities in terms of the region's two major environmental processes, hydrology and fire regime. We next developed several conceptual transitional models that provide more detail on the characteristics of fire regimes that determine successional and disturbance transitions between communities. Transitions between communities in the models were based largely upon personal field experience, aerial photography, and limited data, such as tree ages and organic soil 14C dates. We used our best professional judgment to fill information gaps. Major assumptions in the models were the ready availability of seeds, a long-term perspective for development of communities, and differences in rates of change across a transition depending on direction of change. The models will assist land managers to understand long-term implications of their management decisions. [ABSTRACT FROM AUTHOR]

The disappearance of Acropora palmata from reefs in the Florida Keys National Marine Sanctuary (FKNMS) represents a significant loss in the amount of structurally complex habitat available for reef-associated species. The consequences of such a widespread loss of complex structure on ecosystem processes are still unclear. We sought to determine whether the disappearance of complex structure has adversely affected grazing and invertebrate predation rates on a shallow reef in the FKNMS. Surprisingly, we found grazing rates and invertebrate predation rates were lower in the structurally complex A. palmata branches than on the topographically simple degraded reefs. We attribute these results to high densities of aggressively territorial damselfish, Stegastes planifrons, living within A. palmata. Our study suggests the presence of agonistic damselfish can cause the realized spatial patterns of ecosystem processes to deviate from the expected patterns. Reef ecologists must therefore carefully consider the assemblage of associate fish communities when assessing how the mortality of A. palmata has affected coral reef ecosystem processes. [ABSTRACT FROM AUTHOR]

Large-scale ecosystem restoration efforts, such as those in the Florida Everglades, can be long-term and resource intensive. To gauge success, restoration efforts must have a means to evaluate positive or negative results of instituted activities. Edaphic properties across the Everglades landscape have been determined to be a valuable metric for such evaluation, and as such, a baseline condition from which to make future comparisons and track ecosystem response is necessary. The objectives of this work were to document this baseline condition in the southern most hydrologic unit of the Everglades, Everglades National Park (ENP), and to determine if significant eco-partitioning of soil attributes exists that would suggest the need to focus monitoring efforts in particular eco-types within the ENP landscape. A total of 342 sites were sampled via soil coring and parameters such as total phosphorus (TP), total nitrogen (TN), total carbon (TC), total calcium, total magnesium, and bulk density were measured at three depth increments in the soil profile (floc, 0-10 cm, and 10-20 cm). Geostatistical analysis and GIS applications were employed to interpolate site-specific biogeochemical properties of soils across the entire extent of the ENP. Spatial patterns and eco-type comparisons suggest TC and TN to be highest in Shark River Slough (SRS) and the mangrove interface (MI), following trends of greatest organic soil accumulation. However, TP patterns suggest greatest storages in MI, SRS, and western marl and wet prairies. Eco-partitioning of soil constituents suggest local drivers of geology and hydrology are significant in determining potential areas to focus monitoring for future change detection. [ABSTRACT FROM AUTHOR]

Patterns of mangrove vegetation in two distinct basins of Florida Coastal Everglades (FCE), Shark River estuary and Taylor River Slough, represent unique opportunities to test hypotheses that root dynamics respond to gradients of resources, regulators, and hydroperiod. We propose that soil total phosphorus (P) gradients in these two coastal basins of FCE cause specific patterns in belowground biomass allocation and net primary productivity that facilitate nutrient acquisition, but also minimize stress from regulators and hydroperiod in flooded soil conditions. Shark River basin has higher P and tidal hydrology with riverine mangroves, in contrast to scrub mangroves of Taylor basin with more permanent flooding and lower P across the coastal landscape. Belowground biomass (0-90 cm) of mangrove sites in Shark River and Taylor River basins ranged from 2317 to 4673 g m, with the highest contribution (62-85%) of roots in the shallow root zone (0-45 cm) compared to the deeper root zone (45-90 cm). Total root productivity did not vary significantly among sites and ranged from 407 to 643 g m y. Root production in the shallow root zone accounted for 57-78% of total production. Root turnover rates ranged from 0.04 to 0.60 y and consistently decreased as the root size class distribution increased from fine to coarse roots, indicating differences in root longevity. Fine root biomass was negatively correlated with soil P density and frequency of inundation, whereas fine root turnover decreased with increasing soil N:P ratios. Lower P availability in Taylor River basin relative to Shark River basin, along with higher regulator and hydroperiod stress, confirms our hypothesis that interactions of stress from resource limitation and long duration of hydroperiod account for higher fine root biomass along with lower fine root production and turnover. Because fine root production and organic matter accumulation are the primary processes controlling soil formation and accretion in scrub mangrove forests, root dynamics in the P-limited carbonate ecosystem of south Florida have a major controlling role as to how mangroves respond to future impacts of sea-level rise. [ABSTRACT FROM AUTHOR]

The article focuses on the development of the collective learning framework apply to a study of learning in collaborative ecosystem restoration program in Everglades, Florida. It mentions that the collaborative program aims to restore the ecological integrity of Everglades and was institutionalized under the Water Resources Development Act of 2000. It states that the framework is also used to guide a study of learning processes and products that are linked within the collaborative using case-based and inductive approach at two levels of analysis through survey and interview data. Moreover, applying the framework to study learning offers understanding of the variables relevant to learning in a collaborative setting and identified theoretical propositions.

The article describes the first meeting of INTERFACE, the Integrated Network for Terrestrial Ecosystem Research on Feedbacks to the Atmosphere and ClimatE, which was held on February 28 to March 3, 2011 in Captiva Island, Florida, United States. The primary topics of the workshop are outlined, including nutrient limitation of carbon storage on land, the role of changes in the hydrolic cycle in regulating climate feedbacks, and the role of acclimation in moderating responses of carbon uptake.

BSTRACT [ABSTRACT FROM AUTHOR]

Restoration can be viewed as the process of reestablishing both exogenous drivers and internal feedbacks that maintain ecosystems in a desirable state. Correcting exogenous and abiotic drivers is clearly necessary, but may be insufficient to achieve desired outcomes in systems with self-organizing biotic feedbacks that substantially influence ecological stability and timing of responses. Evidence from a broad suite of systems demonstrates the prevalence of biotic control over key ecosystem attributes such as hydroperiod, nutrient gradients, and landform that are most commonly conceived of as exogenously controlled. While a general theory to predict conditions under which biotic controls exert such strong feedbacks is still nascent, it appears clear that the Greater Everglades/South Florida landscape has a high density of such effects. The authors focus on three examples of biotic control over abiotic processes: hydroperiod and discharge controls exerted by peat accretion in the ridge-slough landscape; phosphorus (P) gradients that emerge, at least in part, from interactions between accelerated peat accretion rates, vegetation structure and fauna; and reinforcing feedbacks among land elevation, aquatic respiration, and carbonate dissolution that produce local and landscape basin structure. The authors propose that the unifying theme of biogeomorphic landforms in South Florida is low extant topographic variability, which allows reciprocal biotic modification of local site conditions via mechanisms of peat accretion (including via effects of landscape P redistribution on primary production) or limestone dissolution. Coupling these local positive feedbacks, which drive patch expansion, with inhibitory or negative feedbacks on site suitability at distance, which serve to constrain patch expansion, provide the mechanistic basis for landscape pattern formation. The spatial attributes (range and isotropy) of the distal negative feedback, in particular, control pattern geometry; elucidating the mechanisms and properties of these distal feedbacks is critical to restoration planning. [ABSTRACT FROM AUTHOR]

Sulfur is broadly recognized as a water quality issue of significance for the freshwater Florida Everglades. Roughly 60% of the remnant Everglades has surface water sulfate concentrations above 1 mg l-1, a restoration performance measure based on present sulfate levels in unenriched areas. Highly enriched marshes in the northern Everglades have average sulfate levels of 60 mg l-1. Sulfate loading to the Everglades is principally a result of land and water management in South Florida. The highest concentrations of sulfate (average 60-70 mg l-1) in the ecosystem are in canal water in the Everglades Agricultural Area (EAA). Potential sulfur sources in the watershed are many, but geochemical data and a preliminary sulfur mass balance for the EAA are consistent with sulfur presently used in agricultural, and sulfur released by oxidation of organic EAA soils (including legacy agricultural applications and natural sulfur) as the primary sources of sulfate enrichment in the EAA canals. Sulfate loading to the Everglades increases microbial sulfate reduction in soils, leading to more reducing conditions, greater cycling of nutrients in soils, production of toxic sulfide, and enhanced methylmercury (MeHg) production and bioaccumulation. Wetlands are zones of naturally high MeHg production, but the combination of high atmospheric mercury deposition rates in South Florida and elevated sulfate loading leads to increased MeHg production and MeHg risk to Everglades wildlife and human consumers. Sulfate from the EAA drainage canals penetrates deep into the Everglades Water Conservation Areas, and may extend into Everglades National Park. Present plans to restore sheet flow and to deliver more water to the Everglades may increase overall sulfur loads to the ecosystem, and move sulfate-enriched water further south. However, water management practices that minimize soil drying and rewetting cycles can mitigate sulfate release during soil oxidation. A comprehensive Everglades restoration strategy should include reduction of sulfur loads as a goal because of the many detrimental impacts of sulfate on the ecosystem. Monitoring data show that the ecosystem response to changes in sulfate levels is rapid, and strategies for reducing sulfate loading may be effective in the near term. A multifaceted approach employing best management practices for sulfur in agriculture, agricultural practices that minimize soil oxidation, and changes to stormwater treatment areas that increase sulfate retention could help achieve reduced sulfate loads to the Everglades, with resulting benefits. [ABSTRACT FROM AUTHOR]

The Everglades is the largest subtropical wetland in the United States. Because of its size, floral and faunal diversity, geological history and hydrological functions on the Florida landscape, the remaining Everglades are considered to be the crown jewel of U.S. wetlands. It is also called a 'sentinel wetland' to test our society's resolve for ecosystem restoration. Originally called Pa-hay-okee ('grassy lake') by the American Indians, it was later popularized as the 'river of grass' by Marjory Stoneman Douglas. This metaphor unfortunately has led to a simplistic view of the complexities of the Everglades ecosystem and how it functions on the landscape. Often incorrectly referred to as the 'marsh' or 'swamp,' the Everglades is a fen peatland or alkaline mire. These are important distinctions when one considers how different marshes and swamps are from peatlands in terms of their hydrologic controls, biogeochemistry, rate of peat development, plant and animal communities and-importantly-succession patterns. This paper provides a brief review of the geological processes that led to the development of the Everglades, compares historic and current hydrologic flow patterns, assesses nutrient conditions, presents information on vegetation communities and succession patterns, and provides a new peatland classification of the Everglades system, which may help in the development of a more appropriate restoration management framework. [ABSTRACT FROM AUTHOR]

The article presents a study on adaptive management approach between scientific and policy-based hypotheses to evaluate multiple hypotheses regarding ecosystem behavior. It states that ecosystem presents unpredictable behavior which posts important challenge for natural resource management. It also discusses and evaluates the high concentration of NO3- in Florida springs which leads to vast growth rates of algae.

Defining success targets in restoration and how social values affect them are two commonly discussed issues in restoration today. We believe that how success is commonly defined—with vague terms such as “healthy ecosystem” or cited as a return to a previous, historic state—needs to be reevaluated. With the increasing number of novel ecosystems, there is an increasing conflict between the ecosystem concept, social values, and restoration. This arises from the fact that ecosystems are defined by the values of the scientists describing them, necessarily constraining the ecosystem to a generally static concept. It is not directly the concept, but how it is perceived through our filter of social values that represses the creativity and innovation needed in restoration today. Within restoration, we feel that the ecosystem concept does a disservice by ignoring the increasing number of novel systems, and that hinders real progress in a time when hesitation can be costly. To best illustrate this, we offer the example of restoration of the Florida Everglades and how it has become a novel system in pattern and process. We suggest renaming the Everglades “The Semiglades” in hopes of opening a dialog to expose social/ecosystem biases and include novel landscapes in management and planning. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an integrated hydrodynamic modeling and probability analysis approach to assess the long-term effects of changing river inflows on the estuarine ecosystem. The probability analysis method, which is popularly used in advanced hydrological frequency analysis of river flows and rainfalls, has been applied to analyze the effects of changing inflow on salinity and thus on oyster ecology in Apalachicola Bay. Long-term salinity data were predicted through the application of a calibrated 3D hydrodynamic model under two river inflow conditions over a 10-year period. The first flow represents the historic flow. The 2nd flow condition, called Scenario-1, represents a regulated flow scenario to account for the potential increasing upstream water demands. Two stations, Mid Bay and Dry Bar, in the bay were selected to examine the estuarine responses. Under the historic flow condition, the maximum probability salinity at Dry Bar in the rich oyster reef is near 24ppt, within the optimal salinity range for oyster growth of 16–26 ppt (Harned et al., 1996); the maximum probability salinity at Mid Bay station is 27ppt, beyond the optimal salinity for oyster growth in mid-bay area where there is no oyster reef around. While it is difficult to examine the difference between two scenarios by conventional time series analysis of river flows and salinity, probability analysis reasonably characterizes and quantifies the changes of river flow and salinity patterns over the 10-year period. The Scenario-1 has caused the increase of the probability in low flows. Higher probability of low flows for the regulated flow scenario shortens the period of optimal salinity in the oyster reef, and cause substantial increase of exceedance probability of higher salinity in the oyster reef to the level beyond the optimal salinity range for oyster growth. The probability analysis approach has demonstrated its advantage for the risk assessments of the long-term estuarine ecohydrological effects under various regulated inflow scenarios to support estuarine water resources managements. [Copyright &y& Elsevier]

To be successful, conservation practitioners and resource managers must fully integrate the effects of climate change into all planning projects. Some conservation practitioners are beginning to develop, test, and implement new approaches that are designed to deal with climate change. We devised four basic tenets that are essential in climate-change adaptation for conservation: protect adequate and appropriate space, reduce nonclimate stresses, use adaptive management to implement and test climate-change adaptation strategies, and work to reduce the rate and extent of climate change to reduce overall risk. To illustrate how this approach applies in the real world, we explored case studies of coral reefs in the Florida Keys; mangrove forests in Fiji, Tanzania, and Cameroon; sea-level rise and sea turtles in the Caribbean; tigers in the Sundarbans of India; and national planning in Madagascar. Through implementation of these tenets conservation efforts in each of these regions can be made more robust in the face of climate change. Although these approaches require reconsidering some traditional approaches to conservation, this new paradigm is technologically, economically, and intellectually feasible. [ABSTRACT FROM AUTHOR]

This paper documents the analyses that were conducted with regards to investigating an appropriate Minimum Mapping Unit (MMU) to be used to capture the potential changes in vegetation patterns for a 10,924 square km restoration project being conducted in south Florida, USA. Spatial landscape and class metrics that were shown to change predictably with increasing grain size were adopted from previous studies and applied to a multi-scale analysis. Specifically, this study examines the effects of changing grain size on landscape metrics, utilizing empirical data from a real landscape encompassing 234,913 ha of south Florida's Everglades. The objective was to identify critical thresholds within landscape metrics, which can be used to provide insight in determining an appropriate MMU for vegetation mapping. Results from this study demonstrate that vegetation heterogeneity will exhibit dissimilar patterns when investigating the loss of information within landscape and class metrics, as grain size is increased. These results also support previous findings that suggest that landscape metric ''scalograms'' (the response curves of landscape metrics to changing grain size), are more likely to be successful for linking landscape pattern to ecological processes as both pattern and process in ecological systems often operate on multiple scales. This study also incorporates an economic cost for various grain dependant vegetation mapping scales. A final selection of the 50 9 50 m grain size for mapping vegetation was based on this study's investigation of the ''scalograms'', the costs, and a composite best professional judgment of seasoned scientists having extensive experience within these ecosystems. [ABSTRACT FROM AUTHOR]

Sea-level rise presents an imminent threat to freshwater-dependent ecosystems on small oceanic islands, which often harbor rare and endemic taxa. Conservation of these assemblages is complicated by feedbacks between sea level and recurring pulse disturbances (eg hurricanes, fire). Once sea level reaches a critical level, the transition from a landscape characterized by mesophytic upland forests and freshwater wetlands to one dominated by mangroves can occur suddenly, following a single storm-surge event. We document such a trajectory, unfolding today in the Florida Keys. With sea level projected to rise substantially during the next century, ex-situ actions may be needed to conserve individual species of special concern. However, within existing public conservation units, managers have a responsibility to conserve extant biodiversity. We propose a strategy that combines the identification and intensive management of the most defensible core sites within a broader reserve system, in which refugia for biota facing local extirpation may be sought. [ABSTRACT FROM AUTHOR]

Abstract: The continental shelf of the southeast United States forms one of North America''s Large Marine Ecosystems (LME). Despite increased attention on ecosystem management, fisheries within this LME continue to be managed on a single stock basis, in part because interactions among species and environmental effects are poorly understood. Using fishery data from two different sources (recreational and commercial), we applied multivariate statistical techniques to elucidate spatial and temporal dynamics of reef fish assemblages. Spatial analyses of species composition revealed a zoogeographic boundary near Cape Canaveral, Florida, suggesting that management of reef fishes could be applied to the northern and southern regions with discrimination. Temporal analyses revealed, in general, gradual changes in species composition of landings, but with primary shifts in 1992 and again in 1999–2000. Chronological patterns, evident in these two independent data sets, bear the signature of one or more trending factors, which in this LME could include increased exploitation, spread of invasive species, habitat degradation, or climate change. [Copyright &y& Elsevier]

The article presents a study pertaining to the responses of components of the ridge and slough landscape to climate variability and 20th century water management in Everglades, Florida. It explores the importance of conducting the study on Everglades restoration because this is provides data on the function and structure of wetland communities. Moreover, this can be used for developing strategies to obtain sustainable ecosystem restoration.

Florida gar, Lepisosteus platyrhincus DeKay, were sampled in two canal systems in south Florida during 2000–2001 to estimate age, growth and mortality as part of the Everglades ecosystem-restoration effort. Tamiami (C-4) and L-31W canal systems had direct connections to natural wetlands of the Everglades and harboured large Florida gar populations. Of 476 fish aged, maximum ages were 19 and 10 years for females and males, respectively. Maximum sizes were also larger for females compared with males (817 vs 602 mm total length). Overall, female Florida gar from both Tamiami and L-31W were larger at age than males from L-31W that, in turn, were larger at any given age than males from Tamiami. Females also had lower rates of annual mortality ( Z = 0.21) than males from L-31W ( Z = 0.31) or males from Tamiami ( Z = 0.54). As a large and long-lived apex predator in the Everglades, Florida gar may structure lower trophic levels. Regional- and sex-specific population parameters for Florida gar will contribute to the simulation models designed to evaluate Everglades restoration alternatives. [ABSTRACT FROM AUTHOR]

There is growing interest in implementing market-like programs that would pay farmers and ranchers for producing environmental services (beyond those that generate food and fiber) from working agricultural lands. However, few examples exist of programs that pay directly for quantified services. Since 2005, a coalition of non-governmental environmental organizations, state and federal agencies, ranchers, and researchers has been developing a Pay-for-Environmental Services (PES) program that would compensate cattle ranchers in Florida's northern Everglades region for providing water storage and nutrient retention on private lands. We use our experience with this program to identify key challenges to PES program design, including identifying a buyer and defining the environmental services; agreeing upon credible, yet practical, approaches to quantifying the services provided; reducing programmatic costs in light of existing policies and complex regulatory issues; and maintaining an adaptive approach to program design and implementation, while satisfying the concerns of multiple stakeholders. [ABSTRACT FROM AUTHOR]

• The teabag index (TBI) was adopted to quantify subtropical wetland decomposition. • Land-use intensification, grazing, and fire interactively affected decomposition. • Hydrology and climate contributed to spatial–temporal variation in decomposition. • TBI is a useful indicator to inform wetland ecosystem service management. Understanding how global change drivers and their interactions affect decomposition in wetlands embedded in agricultural landscapes remains challenging, especially in tropical and subtropical biomes, which are disproportionately important for global carbon cycling yet with high uncertainties. In a long-term whole-ecosystem experiment, we used a widely-adopted indicator of decomposition, the Teabag Index (TBI), to investigate individual and interactive effects of surrounding land-use intensity, cattle grazing, and prescribed fire on seasonal wetland decomposition (i.e., decay rate k , and stabilization factor S) in an exemplar subtropical landscape in central-south Florida, USA. We ask: (1) How do land-use intensity and management practices affect the decomposition in seasonal wetlands? (2) How does wetland decomposition vary with hydrological gradient and seasonal climatic condition? (3) What are the dominant direct and indirect pathways through which land-use intensity and management practices affect wetland decomposition? Our results showed that, overall, surrounding land-use intensity exerted much stronger effects on litter decomposition compared to grazing and prescribed fire, and cattle grazing reduced decomposition rate k. There was a complex three-way interaction among land-use intensity, grazing and fire on the stabilization factor S – a proxy related to carbon sequestration potential. Grazing-fire interactive effects on S only existed in wetlands embedded in intensively-managed landscapes, where grazing reduced S in burned wetlands but did not affect S in unburned wetlands. Decay rate k showed profound temporal variation primarily driven by seasonal climatic conditions (especially precipitation), whereas S varied spatially along the hydrological gradient. Our structural equation modeling (SEM) analyses further revealed that effects on k were also indirectly manifested through changes on soil C/N, C/P, and pH, while effects on S were manifested through alterations in soil C/P ratio, pH, soil nutrients and water content. Our TBI results suggest that anthropogenic environmental changes, including land-use intensification, livestock introduction and fire suppression, could compromise carbon sequestration potential in tropical and subtropical seasonal wetlands. Our research highlights the importance of considering landscape context in wetland management and demonstrates the use of TBI as an indicator to quantify and inform combinations of land management and agricultural practices could conserve wetlands and sustain their vital functions and services, especially from the lens of promoting carbon storage and nutrient retention services. [ABSTRACT FROM AUTHOR]

The article discusses the ecosystem in South Florida. It examines the rainfall frequency, water quality and quantity, wetlands, birds and animal population in the location. It mentions that South Florida has diverse subtropical, coastal and marine areas that are being protected by the South Florida Water Management District (SFWMD). According to the author, authorities are establishing laws such as water policy, flood control and reforestation, to further protect and preserve the ecosystem of South Florida.

Nutrient loading and eutrophication in coastal waters are the causes of water quality degradation and loss of marine biota, which has led to ecological imbalance. Understanding and modeling the level of eutrophication as a function of environmental parameters can be beneficial to coastal ecosystem management. The limitation of deterministic and empirical models in accurately predicting the level of algal blooms, and the nonlinear relationship between the water quality and environmental parameters and that of the level of chlorophyll a necessitate a new approach using machine learning and data-driven modeling. A multilayer perceptron-back propagation (MLP-BP) algorithm of artificial neural network (ANN) was used to predict the level of eutrophication (chlorophyll a) from water quality parameters monitored at two Florida Bay water quality monitoring stations (FLAB03 and FLAB14). Based on the correlation of monthly nutrients (total phosphate, nitrite, ammonium) and other water data (temperature, turbidity, and dissolved oxygen) to the level of chlorophyll a, an input-output data structure was selected. Seven input data scenarios were studied, and model performance was compared using four indices. Monthly data from 1992 to 2004 were partitioned into training and testing subsets. Results show that chlorophyll a was predicted well with the selected inputs, with an average R² and model efficiency (E) of 0.856 and 0.582, respectively. Prediction with antecedent chlorophyll a alone gave a stable result with smaller error and higher performance attributed to easier and more efficient training. It was also found that ANN performed better at FLA03 than at FLA14. It is shown that the MLP-BP technique is applicable to the monitoring and prediction of algal blooms and will be crucial to coastal watershed management. [ABSTRACT FROM AUTHOR]

In this article, I offer an institutional history of the ecosystem concept, tracing shifts in its meaning and application as it has become the key organizing principle for the Everglades restoration program in Florida. Two institutional forms are analyzed here: (1) quasi-governmental organizations, a term I use to describe interagency science collaboratives and community stakeholder organizations, and (2) government bureaucracies, which are the administrative agencies tasked with Everglades restoration planning and implementation. In analyzing these knowledge trajectories, I both document the complex networks of relations that facilitate the ecosystem's emergence as an object of knowledge and examine the bureaucratic claims to authority that circumscribe the ecosystem's transformation into policy. [ABSTRACT FROM AUTHOR]

Abstract: As more people visit natural areas for tourism and recreation purposes, it is becoming increasingly important to understand the value they place on these natural resources. Specifically, tourists to Florida have been increasingly interested in visiting natural areas, forests, parks, and preserves—highlighting the importance of this new and growing phenomenon. We analyze visitors’ demand for nature-based recreation in the Apalachicola River region of Florida using the travel cost method. The results from a count data regression model reveal that on average visitors would pay $74.18 per visit-day for nature-based recreation resulting in a total economic value of $484.56 million attributable to nature-based recreation in the Apalachicola River region. Results of this study provide useful information for natural resources management in the region and a rationale to preserve Florida''s unique ecosystems. [Copyright &y& Elsevier]

The removal of plants and soil to bedrock to eradicate exotic invasive plants within the Hole-in-the-Donut (HID) region, part of the Everglades National Park (Florida), presented a unique opportunity to study the redevelopment of soil and the associated microbial communities in the context of short-term primary succession and ecosystem restoration. The goal of this study was to identify relationships between soil redevelopment and activity and composition of methanogenic assemblages in HID soils. Methane production potentials indicated a general decline in methanogenic activity with restoration age. Microcosm incubations strongly suggested hydrogenotrophic methanogenesis as the most favorable pathway for methane formation in HID soils from all sites. Culture-independent techniques targeting methyl coenzyme M reductase genes (mcrA) were used to assess the dynamics of methanogenic assemblages. Clone libraries were dominated by sequences related to hydrogenotrophic methanogens of the orders Methanobacteriales and Methanococcales and suggested a general decline in the relative abundance of Methanobacteriales mcrA with time since restoration. Terminal restriction fragment length polymorphism analysis indicated methanogenic assemblages remain relatively stable between wet and dry seasons. Interestingly, analysis of soils across the restoration chronosequence indicated a shift in Methanobacteriales populations with restoration age, suggesting genotypic shifts due to site-specific factors. [ABSTRACT FROM AUTHOR]

The article discusses the regulatory controls and ecosystem management services in Apalachicola-Chattahoochee-Flint (ACR) River Basin, and explores the impact of the services on decision making in Georgia, Alabama and Florida. It is noted that water allocation became the problem of the management because party states based their allocation relative to the sustenance of larger resource. The Georgia Environmental Protection Division of the Department of National Resources is authorized to administer its surface and groundwater as well as irrigation uses of Flint River. The states are given correlative rights to use the services and resource sharing.

The Australian punk tree Melaleuca quinquenervia is a notorious invasive weed that threatens the biological integrity of Florida's Everglades ecosystems. A comprehensive plan initiated to manage M. quinquenervia includes an ambitious biological control program, and as part of this program we investigated the origins and invasion history of M. quinquenervia in Florida. Scrutiny of public and private records showed that extant populations derive from more than a dozen introductions, with the earliest occurring during 1886 in Sarasota County. Six sources, some Australian and some extra-Australian, have contributed to Florida's populations. The tree became naturalized in southern Florida during the 1920s, but a paucity of records makes it difficult to determine when naturalized populations began to proliferate via an exponential growth phase. Human distribution of seeds and seedlings is a confounding factor in attempting to decipher rates of M. quinquenervia invasion. [ABSTRACT FROM AUTHOR]

Mathematical relations that use easily measured variables to predict difficult-to-measure variables are important to resource managers. In this paper we develop allometric relations to predict total aboveground biomass and individual components of biomass (e.g., leaves, stems, branches) for three species of mangroves for Everglades National Park, Florida, USA. The Greater Everglades Ecosystem is currently the subject of a 7.8-billion-dollar restoration program sponsored by federal, state, and local agencies. Biomass and production of mangroves are being used as a measure of restoration success. A technique for rapid determination of biomass over large areas is required. We felled 32 mangrove trees and separated each plant into leaves, stems, branches, and for Rhizophora mangle L., prop roots. Wet weights were measured in the field and subsamples returned to the laboratory for determination of wet-to-dry weight conversion factors. The diameter at breast height (DBH) and stem height were also measured. Allometric equations were developed for each species for total biomass and components of biomass. We compared our equations with those from the same, or similar, species from elsewhere in the world. Our equations explained ≥93% of the variance in total dry weight using DBH. DBH is a better predictor of dry weight than is stem height and DBH is much easier to measure. Furthermore, our results indicate that there are biogeographic differences in allometric relations between regions. For a given DBH, stems of all three species have less mass in Florida than stems from elsewhere in the world. [ABSTRACT FROM AUTHOR]

Long-term studies of the responses of plant populations to fire can inform adaptive management of ecosystems. I present results of an analysis of responses of a fire-adapted plant, Pityopsis graminifolia (Michx.) Nutt. (silkgrass goldenaster), to season of fire from 2001 to 2005 in a longleaf pine (Pinus palustris P. Miller) sandhill community in north Florida. Replicated May-burned and January-burned plots had been burned biennially from 1986 to 2004. Previous work in the early 1990s showed that populations of this species benefited more from fires during the peak lightning fire season (i.e., May) than from January fires. In 2001, however, shoot densities in both treatments were substantially lower than in 1992 and remained relatively low through March 2005. Shoot densities were significantly higher in May-burned plots than in January-burned plots between 2001 and 2005. May fires significantly increased shoot densities in 2002 (relative to January fires), but did not in 2004. Shoot densities in January-burned plots remained remarkably stable between 2001 and 2005. As in the early 1990s, May fires were consistently more effective than January fires at stimulating flowering, which in turn produced higher seedling densities. Seedling survival was low, however, as in the early 1990s. Positive short-term effects of lightning-season fires on long-term population trends in this fire-adapted species appear to be substantially reduced by periodic population crashes, inconsistent short-term effects on clonal growth, and inherently low seedling establishment rates. [ABSTRACT FROM AUTHOR]

Eddy covariance was used to measure energy fluxes from July 2000 – June 2002 above the tree canopy and above the understory in a mature, naturally regenerated slash pine (Pinus elliottii Engelm. var. elliottii) – longleaf pine (Pinus palustris Mill.) flatwoods forest. Understory latent energy (λE) and sensible heat (H) fluxes accounted for 45% and 55% of whole-ecosystem fluxes, respectively, with strong seasonal variation in the proportion of λE attributable to the understory. The partitioning of net radiation (Rnet) to λE and H also changed seasonally, with half-hourly mean ecosystem H in the winter peaking at 175 W·m–2, almost twice as large as λE. In contrast, half-hourly ecosystem λE and H remained almost equal throughout the day in July and August, with mean midday peaks of approximately 200 W·m–2. Maximum hourly evapotranspiration (ET) in the months of July and August was 0.32 and 0.29 mm·h–1 for 2000 and 2001, respectively. For a variety of environmental conditions, mean daily ET was approximately 2.7 mm in the summer and 1.3 mm in the winter. Annual ET for the first year was 832 mm, or 87% of annual precipitation (956 mm). Although leaf area index was higher in the second year, annual ET was only 676 mm, which is considerably lower than that of the previous year, but it still accounted for approximately the same proportion (84%) of the much lower annual precipitation (811 mm). Canopy conductance declined as soils dried, changing patterns of partitioning of Rnet to λE. [ABSTRACT FROM AUTHOR]

Because ecosystem approaches to management adhere to ecological systems rather than human-defined boundaries, collaboration across jurisdiction, agencies, and land ownership is often necessary to achieve effective management of transboundary resources. Local natural resource and land use planners increasingly recognize that while ecosystem management requires looking beyond specific jurisdictions and focusing on broad spatial scales, the approach will partly be implemented at the local level with the coordination of local policies across larger landscapes. This article evaluates the collective capabilities of local jurisdictions to manage large transboundary ecological systems in Florida. Specifically, it combines plan evaluation with geographic information systems (GIS) techniques to map, measure, and analyze the existing mosaic of management across selected ecosystems in the southern portion of the State. Visual and statistical results indicate significant gaps in the management framework of southern Florida that, if filled, could achieve a greater level of consistency and more complete coverage of ecosystem management policies. Based on the spatial distribution of 58 ecosystem management indicators, notable gaps persist in the southwest coast, southeast coast, and central Everglades ecosystems, particularly for wildlife corridors and collaboration with neighboring jurisdictions. We also test for spatial autocorrelation of ecosystem planning scores and find that local jurisdictions with strong ecosystem management capabilities tend to cluster within specific ecosystems. Based on the findings, we make recommendations on how and where local plans can be strengthened to more effectively attain the objectives of ecosystem approaches to management. [ABSTRACT FROM AUTHOR]