Coastal Mangrove Forests Research Articles

Developing indicators to assess climate change adaptable in Ba ria-Vung tau province and proposed improve solutions

With the target of research is assess and classify the ability to adapt climate change for districts of Ba Ria-VungTau (BR-VT) province and proposed improve solutions, the authors used MCA, Entropy weighting and SAW methods to evaluate and achieve the results as follows: Developing indicators to assess climate change adaptable in BR-VT province includes 12 topics and 24 indicators corresponding to the provincial level. And adaptation indicators for the districts, including 9 topics and 16 indicators. The indicators belongs to two main groups to assess the vulnerability and adaptable to climate change; The results were evaluated by the provincial level adaptation period 2009 - 2012 shows that adaptation index has increased over the years and reached an average level of adaptation (52 points) for climate change and fluctuation of adaptation index is from 50.97 to 52.96; The adaptation index of the districts is low. Ba Ria city has the highest adaptation index 57.61 points – at average level, follows by Vung Tau city. The lowest is 49.29 points in Chau Duc district. Besides, authors proposing solutions to improve adaptation to climate change as the solution to landslide coast control, land erosion, maintain and development of coastal mangrove forests of the province and propose rice variety can adapt to saline aluma and get yield stable.

Estimation of Wind-Driven Coastal Waves Near a Mangrove Forest Using Adaptive Neuro-Fuzzy Inference System

At the coastline of the Carey Island, mangroves provide natural protection against the wind-driven coastal waves. The area is located at the west Malaysia within the waters of the Straits of Malacca. Recently, its coastline has been exposed to increasing rates of coastal erosion due to mangrove deforestation. In order to provide mitigating measures, it is necessary to study wave characteristics in this region. For this purpose, we collected 5 years (2009 to 2013) of hourly measurements for wind direction, wave height, wind speed and wave period. Moreover, we used the adaptive neuro-fuzzy inference system (ANFIS) to estimate the wave period and height. The model was trained using the measured data. The validation of the model gave satisfactory R2 values of 0.8484 and 0.9496 for wave height and wave period, respectively. The findings from this study suggest that fuzzy logic based technique satisfactorily predicts the differences between multiple inputs and single output in terms of non-linear relationship. The developed model can be used to further study the effect of non-linear wind-driven waves on the depleting coastal mangrove forests in similar tropical and sub-tropical areas. We suggest further research to test the model in different geographical locations, such as in deep-ocean, narrow straits and other coastal sites, which were not covered in this study.

Mangrove forests store high densities of carbon across the tropical urban landscape of Singapore

Tropical forested ecosystems provide multiple ecosystem services to rural and urban landscapes, with carbon storage gaining particular attention. Deforestation due to rural-urban transitions may lead to a reduction in carbon storage ability. Coastal mangrove forests are particularly at risk from deforestation due to their location in the rapidly urbanizing coastal zone, and the city state of Singapore is an extreme example, losing as much as 90 % of its original mangrove cover due to land reclamation and reservoir construction. Knowledge of mangrove ecosystem services may allow better conservation, restoration and incorporation of remaining mangrove patches into the urban landscape. Focusing on the regulating ecosystem service of carbon storage, mangrove carbon stocks have been estimated for Singapore using a combination of field and remote sensing techniques. Biomass carbon showed substantial spatial variation, with old, contiguous mangrove patches containing a higher density of biomass carbon than fragmented, river-fringing or restored mangroves. In total, national biomass carbon equated to 116,117.1 megagrams of carbon (Mg C), and a coarse estimate of the total carbon stock (including soil carbon) suggests that Singapore’s mangroves may store 450,571.7 Mg C. While lower than other regional estimates focused on natural, oceanic mangroves, this is a significant carbon stock for a disturbed, urban mangrove system, and may be equivalent to the average annual carbon emissions of 621,000 residents. This analysis, alongside a review of other urban forest studies, highlights the importance of forested ecosystems such as mangroves in providing a carbon storage ecosystem service to urban areas.

Coastal sediment elevation change following anthropogenic mangrove clearing

Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” catching terrestrial sediment, thus preventing smothering of subtidal coral reefs. Coastal development that removes mangrove habitat may impact adjacent nearshore coral reefs through sedimentation and nutrient loading. We examined differences in sediment elevation change between patches of open-coast intact and anthropogenically cleared red mangroves (Rhizophora mangle) on the east side of Turneffe Atoll, Belize, to quantify changes following mangrove clearing. Samples were collected over a 24 month period at five study sites, each containing paired intact (+mangrove) and cleared (-mangrove) plots. Five sediment elevation pins were deployed in each plot: behind areas cleared of mangroves (-mangrove) and behind adjacent intact mangroves (+mangrove). Sediment elevation increased at intact mangrove sites (M = +3.83 mm, SE = 0.95) whereas cleared mangrove areas suffered elevation loss (M = −7.30 mm, SE = 3.38). Mangroves inshore of partial or continuous gaps in the adjacent fringing reefs had higher rates of elevation loss (M = −15.05 mm) than mangroves inshore of continuous fringing reefs (M = −1.90 mm). Our findings provide information on potential effects of mangrove clearing and the role of offshore habitat characteristics on coastal sediment trapping and maintenance of sediment elevation by mangroves. With implications for coastline capacity to adjust to sea level rise, these findings are relevant to management of coastal fringing mangrove forests across the Caribbean.

Plant–plant interactions in a subtropical mangrove‐to‐marsh transition zone: effects of environmental drivers

AbstractQuestionsDoes the presence of herbaceous vegetation affect the establishment success of mangrove tree species in the transition zone between subtropical coastal mangrove forests and marshes? How do plant–plant interactions in this transition zone respond to variation in two primary coastal environmental drivers?LocationSubtropical coastal region of the southern United States.MethodsWe conducted a greenhouse study to better understand how abiotic factors affect plant species interactions in the mangrove‐to‐marsh transition zone, or ecotone. We manipulated salinity (fresh, brackish or salt water) and hydrologic conditions (continuously saturated or 20‐cm tidal range) to simulate ecotonal environments. Propagules of the mangroves Avicennia germinans and Laguncularia racemosa were introduced to mesocosms containing an established marsh community. Both mangrove species were also introduced to containers lacking other vegetation. We monitored mangrove establishment success and survival over 22 mo. Mangrove growth was measured as stem height and above‐ground biomass. Stem height, stem density and above‐ground biomass of the dominant marsh species were documented.ResultsEstablishment success of A. germinans was reduced under saturated saltwater conditions, but establishment of L. racemosa was not affected by experimental treatments. There was complete mortality of A. germinans in mesocosms under freshwater conditions, and very low survival of L. racemosa. In contrast, survival of both species in monoculture under freshwater conditions exceeded 62%. The marsh species Distichlis spicata and Eleocharis cellulosa suppressed growth of both mangroves throughout the experiment, whereas the mangroves did not affect herbaceous species growth. The magnitude of growth suppression by marsh species varied with environmental conditions; suppression was often higher in saturated compared to tidal conditions, and higher in fresh and salt water compared to brackish water.ConclusionsOur results indicate that herbaceous marsh species can suppress mangrove early seedling growth. Depending on species composition and density, marsh plants can slow mangrove landward migration under predicted climate change scenarios as salinity in freshwater and oligohaline wetlands increases with rising sea levels. Change in the relative coverage of mangrove forests and marshes will depend on both the ability of marsh species to migrate further inland as mangroves advance, and the ability of shoreline mangroves to adjust to rising sea level through accretionary processes.

B. Understanding Climate Change Vulnerability Assessments: Application to Coastal Mangrove Forests

Increased global temperature and its consequences pose threats to coastal habitat health and productivity, which, in turn, impact biodiversity, fisheries and coastal integrity. Assessment of vulnerability of the coastal area therefore involves not only investigating climate and ocean exposure and their potential impact but should likewise include evaluating socio-economic development and the ability of affected communities to cope with such changes. To this end, three tools were developed to assist local government units in conducting assessments of their respective areas. The first is the Integrated Coastal Sensitivity, Exposure, Adaptive Capacity to Climate Change VA Tool (I-C-SEA-Change by Licuanan et al.), which is a scoping and rapid reconnaissance tool intended to offer comparison of general vulnerabilities across barangays. For adaptation planning, I-C-SEA-Change must be complemented with the two other tools, TURF (Tool for Understanding Resilience of Fisheries by Mamauag et al.) and CIVAT (Coastal Integrity VA Tool by Siringan et al.). TURF and CIVAT are !ner resolution analyses intended to provide direct guidance in developing CC adaptation strategies. Specifically for mangrove ecosystem, vulnerability assessment includes land-use planning (including the marine environment), measures of habitat protection, measures of coastal integrity and presence/ absence of marine infrastructure. In general therefore, adaptability of the mangrove ecosystem to climate change can be enhanced with synergistic management of the watershed and the coast.

Historical and contemporary cultural ecosystem service values in the rapidly urbanizing city state of Singapore.

Cultural ecosystem services are a function of people and place, so may change as a location transitions from rural to urban. Singapore has undergone rapid urbanization after its independence in 1965, with a concomitant decline in natural habitat extent and accessibility. Using coastal mangrove forests as a case study habitat, changing cultural values were explored with a novel array of techniques, including qualitative archival analysis (photographs, oral histories), current sources (publically uploaded social media photographs), and surveys of (a) the general public and (b) visitors to publically accessible mangroves. Cultural value changed through time, with a significant transition from intrinsic, intrapersonal values (spiritual, cultural heritage) to instrumental, interpersonal values (recreation, education). Additionally, cultural value varied between different mangroves depending on their public accessibility, and the evolving degree of human interaction with the ecosystem as urban development occured. Cultural values change as development transitions, though mangroves still play an important cultural role in a heavily urbanized environment.

Spatio-temporal assessment of ecological disturbance and its intensity in the Mangrove forest using MODIS derived disturbance index

Abstract. The mangrove ecosystem of Sundarbans region plays an important ecological and socio-economical role in both India and Bangladesh. The ecological disturbance in the coastal mangrove forests are mainly attributed to the periodic cyclones caused by deep depression formed over the Bay of Bengal. In the present study, three of the major cyclones in the Sundarbans region were analyzed to establish the cause-and-effect relationship between cyclones and the resultant ecological disturbance. The Moderate Resolution Imaging Spectroradiometer (MODIS) time-series data was used to generate MODIS global disturbance index (MGDI) and its potential was explored to assess the instantaneous ecological disturbance caused by cyclones with varying landfall intensities and at different stages of mangrove phenology. The time-series MGDI was converted into the percentage change in MGDI using its multi-year mean for each pixel, and its response towards several cyclonic events was studied. The affected areas were identified by analyzing the Landsat-8 satellite data before and after the cyclone and the MGDI values of the affected areas were utilized to develop the threshold for delineation of the disturbed pixels. The selected threshold was applied on the time-series MGDI images to delineate the disturbed areas for each year individually to identify the frequently disturbed areas. The classified intensity map could able to detect the chronically affected areas, which can serve as a valuable input towards modelling the biomigration of the invasive species and efficient forest management.

Mangrove Species Identification: Comparing WorldView-2 with Aerial Photographs

Remote sensing plays a critical role in mapping and monitoring mangroves. Aerial photographs and visual image interpretation techniques have historically been known to be the most common approach for mapping mangroves and species discrimination. However, with the availability of increased spectral resolution satellite imagery, and advances in digital image classification algorithms, there is now a potential to digitally classify mangroves to the species level. This study compares the accuracy of mangrove species maps derived from two different layer combinations of WorldView-2 images with those generated using high resolution aerial photographs captured by an UltraCamD camera over Rapid Creek coastal mangrove forest, Darwin, Australia. Mangrove and non-mangrove areas were discriminated using object-based image classification. Mangrove areas were then further classified into species using a support vector machine algorithm with best-fit parameters. Overall classification accuracy for the WorldView-2 data within the visible range was 89%. Kappa statistics provided a strong correlation between the classification and validation data. In contrast to this accuracy, the error matrix for the automated classification of aerial photographs indicated less promising results. In summary, it can be concluded that mangrove species mapping using a support vector machine algorithm is more successful with WorldView-2 data than with aerial photographs.

Analyses on phenological and morphological variations of mangrove forests along the southwest coast of Bangladesh

Drastic changes in river discharge and salinity levels are threatening the phenology and morphology of the coastal mangrove forests of the Sundarbans of Bangladesh. We have used AVHRR GIMMS (1985–2006) and MODIS (2005–2010) satellite Normalized Difference Vegetation Index (NDVI) data to identify the temporal variation of the phenology of the mangroves. Linear interpolation and Fourier-based adjustment were applied to remove noise from the NDVI time series. Then linear regression analysis on a single area (8 km ✕ 8 km) and a composite of 36 areas for three NDVI statistics the annual minimum, annual average, and annual maximum were performed--over the time periods 1985–1990, 1990–2000, 2000–2006 and 2005–2010 to identify possible functional changes in NDVI time series around the Sundarbans. Furthermore, we used fourteen LANDSAT images spanning the period 1989–2010 to estimate the spatiotemporal rate of shoreline changes over the three time periods 1989–2000, 2000–2006, and 2006–2010. A decreasing trend in the annual minimum NDVI was observed in most of the areas of the Sundarbans for the period 1990–2000. During the years 2000–2006, the trends of the three NDVI statistics became significantly positive, indicating an improvement of the mangrove phenology. In the period 2005–2010, a decreasing trend in all the NDVI variables was again dominant. The coast underwent rapid erosion from 1989–2000 and 2006–2010. However, the rate substantially declined between 2000 and 2006, when accretion was dominant. The advent of the upstream Farakka barrage caused a significant reduction in the Ganges-Gorai River discharge and increased the salinity in and around the Sundarbans. Our study concludes that this may be responsible for the degradation of mangrove phenology and accelerated erosion in the earlier and recent periods. In the interim, 2000–2006, improved river discharge and salinity levels due to the Ganges water sharing agreement (1996) and dredging of the Gorai River bed (1998–1999) enhanced the mangrove phenology and helped the coast to gain land.

Coastal People Activity on Mangrove Forest Rehabilitation in Mahakam Estuary

Present condition shows that balance and environmental sustainability of mangrove forests in Mahakam Estuary (Delta Mahakam) area has changed which can result negative effect on people activity of coastal communities. Destruction of mangrove forest is caused by intervention and rapid population growth, especially in coastal areas, which result land use change and excessive utilization of natural resources. This condition can lead to degradation of mangrove forest. In order to rehabilitate mangrove forest, active participation from coastal community is needed. In this regard, this research was carried out in order to assess the perception and participation as well as strategies that can be implemented to improve community participation on mangrove forest rehabilitation. The research was conducted in five villages (Saliki, Salo Palai, Muara Badak Ulu, Muara Badak Ilir and Tanjung Limau), Formulation strategies was carried out using SWOT (Strengths, Weaknesses, Opportunities, Threats) method through Focus Group Discussion which combined with Analytical Hierarchy Process to determine the priority of alternative strategies and policies on mangrove forest rehabilitation. The analysis shows that social factor which influences community’s participation towards the rehabilitation of coastal mangrove forest is perception variable. Strategy which is expected to improve community participation in mangrove rehabilitation activities is carried out by optimizing the strength factor and take advantage from the opportunities (Strengths Opportunities Quadrant Strategy). Based on formulated strategies, it can be obtained four priority alternatives which can be implemented to improve coastal community participation, i.e.: 1) Development of rural participatory for mangrove nursery; 2) Generates positive perception on the strengthening coastal communities about the advantage and functions of mangrove forests; 3) control upon re-vegetation and restoration of coastal areas resources which suffer from degradation and deforestation; and 4) Accelerate the establishment of Guidance Unit Team and Technical Guidance Unit of Mangrove Forest.

Vulnerability to coastal flooding and response strategies: The case of settlements in Cameroon mangrove forests

Worldwide, millions of people experience coastal flooding each year, with devastating effects especially in rural coastal settlements in tropical developing countries. This paper investigates the vulnerability of local settlements in the Cameroon mangrove forest zone to flooding, and improves understanding of perceptions and responses to past and current coastal flooding. Six communities in the coastal mangrove forest zone of the extreme SouthWest of Cameroon were investigated. A questionnaire was administered to a total of 200 individuals supplemented by other participatory rapid appraisal tools. The ground positions of the sampled sites as well as their altitudes were recorded for subsequent geospatial analysis.Statistical analysis was performed to show trends. The coordinates of the study sites were superimposed on base topographic maps of 1965, to investigate coastal changes over a period of 43 years. Results show that: (1) changes in coastal area have occurred in the past 43 years either through inland retreat or seaward shifts and accordingly, settlements are differentially vulnerable; (2) settlement submergence, house damage, and landscape deformation are the key impacts of flooding; (3) coastal flooding promotes the deforestation of mangrove forest for fuel wood; (4) current adaptive measures include retreat of settlement, abandonment, and house design modifications; and (5) most adaptive strategies are reactive individual actions which are likely inefficient and unsustainable from a longer term perspective given their limited scope of implementation. The paper recommends external support to improve adaptive capacity in mangrove settlements, review and improvement of existing policies, and development of integrated coastal management strategy for the region.

Preliminary data on Brachyura (Crustacea) in coastal mangrove forests from Tinh Gia (Thanh Hoa province) to Hoi An (Quang Nam province)

The surveying on Brachyura (Crustacea) in coastal mangrove forests from Tinhgia (Thanhhoa province) to Hoian (Quangnam province) was carried out in December, 2003 at 9 localities. 36 crab species, belonging to 5 families were collected and the species number was mainly in the families Ocypodidae and Grapsidae. In addition, there were several wide range species found in the northern fauna as well as in the southern fauna of Vietnam. Crabs were numerous in species in Vietnam mangrove ecosystems. The characteristics of the crab species composition in mangrove forests from Tinhgia to Hoian were following species: Parapyxidognathus deianira, Hemigrapsus penicillatus, Neoepisesarma lafondi, Scopimera curtelsoma, Ocypode sinensis and Metopograpsus thukuhar. All the crab species found in these mangrove stands were burrowers and ground-dwelling animals. The ground-dwelling crabs could be found on the lower parts of the tree trunks.

Evolution in Australasian Mangrove Forests: Multilocus Phylogenetic Analysis of the Gerygone Warblers (Aves: Acanthizidae)

The mangrove forests of Australasia have many endemic bird species but their evolution and radiation in those habitats has been little studied. One genus with several mangrove specialist species is Gerygone (Passeriformes: Acanthizidae). The phylogeny of the Acanthizidae is reasonably well understood but limited taxon sampling for Gerygone has constrained understanding of its evolution and historical biogeography in mangroves. Here we report on a phylogenetic analysis of Gerygone based on comprehensive taxon sampling and a multilocus dataset of thirteen loci spread across the avian genome (eleven nuclear and two mitochondrial loci). Since Gerygone includes three species restricted to Australia's coastal mangrove forests, we particularly sought to understand the biogeography of their evolution in that ecosystem. Analyses of individual loci, as well as of a concatenated dataset drawn from previous molecular studies indicates that the genus as currently defined is not monophyletic, and that the Grey Gerygone (G. cinerea) from New Guinea should be transferred to the genus Acanthiza. The multilocus approach has permitted the nuanced view of the group's evolution into mangrove ecosystems having occurred on multiple occasions, in three non-overlapping time frames, most likely first by the G. magnirostris lineage, and subsequently followed by those of G. tenebrosa and G. levigaster.

Effect of mangrove forest structures on wave attenuation in coastal Vietnam

This paper analyses wave attenuation in coastal mangrove forests in Vietnam. Data from 32mangrove plots of six species located in 2 coastal regions are used for this study. In each plot, mangrove forest structures and wave height at different cross-shore distances are measured. Wave height closely relates to crossshore distances. 92 exponential regression equations are highly significant with R2 >0.95 and P val. <0.001. Wave height reduction depends on initial wave height, cross-shore distances, and mangrove forest structures. This relationship is used to define minimum mangrove band width for coastal protection from waves in Vietnam.

DOCUMENTATION OF INDIGENOUS KNOWLEDGE ABOUT MEDICINAL PLANTS OF PAKISTAN

Indigenous knowledge of wild and cultivated plant use is linked to local culture and history. It should be regarded as a body of knowledge that has continually developed over time without the outside assistance of formal science. Pakistan has 18 different types of ecological zones with a variety of habitat types like the coastal Mangrove forests, the desert subtropical foothills dry and moist areas, the alpine pastures etc. with diverse ethnic composition and ancient civilization. It has rich flora of over 6000 species of flowering plants, conifers and ferns with about 4000 fungal species and 1000 algae are so far reported to occur in different provinces including Kashmir. A very large number is found in northern and northwestern parts of the country. It was estimated in early 1950 that up to 84% of the Pakistani population is dependent on traditional medicine for all or most of their medical needs. Even now, in some parts of the reported area the percentage may be the same or even higher. Western-style allopathic medicines are relatively expensive compared to the traditional herbal medicine, and for people living in hilly areas, usually not available. The use of medicinal plants to cure diseases and relieve physical suffering of both humans and animals, goes back to ancient times. It has been reported that approximately 400-600 medicinal plants are more frequently used in herbal preparations and while several species, which are common in certain areas, are known to be used locally in traditional preparations, they have not been scientifically investigated for wider use. A lot more work therefore needs to be done with regard to collecting and compiling indigenous knowledge of plants, especially amongst living in the western mountains.

Are Laguncularia racemosa galled leaves less attractive to chewing herbivores

Evolutionary interactions between herbivores and plants have resulted in an impressive variety of adaptations, and herbivory pressure has led to the evolution of chemical, mechanical and phenological defense in plants. Coastal mangrove forests provide a very tractable system in which to study the dynamics of herbivory. The objective of this work was to evaluate if galled leaves of the mangrove tree Laguncularia racemosa (L.) Gaerten (Combretaceae) are less consumed by chewing insects. Monthly excursions were carried to the Maracaipe Mangrove in Pernambuco, to collect adult leaves from 60 plants of L. racemosa: 240 ungalled leaves consumed by chewing insects (CL), 240 galled leaves consumed by chewing insects (CLG) and 240 galled leaves not consumed by chewing herbivores (LG). Other leaves were collected in August, in order to quantify total phenolic concentration: 40 intact leaves of individuals with low rate of infestation by galls (LL) and 40 of individuals with high infestation (HL) were thus collected. CLG displayed a lesser loss of foliar area to chewing herbivores. The results show a signifi cant amount of phenols in HL (35.63 mg) and LG (32.7 mg). This high phenol concentration is probably repelling chewing phytophagous. It is known that herbivores tend to avoid leaves that were previously predated by another herbivore. Possibly galls are infl uencing the feeding performance of the chewing insects.

The current refugial rainforests of Sundaland are unrepresentative of their biogeographic past and highly vulnerable to disturbance

Understanding the historical dynamics of forest communities is a critical element for accurate prediction of their response to future change. Here, we examine evergreen rainforest distribution in the Sunda Shelf region at the last glacial maximum (LGM), using a spatially explicit model incorporating geographic, paleoclimatic, and geologic evidence. Results indicate that at the LGM, Sundaland rainforests covered a substantially larger area than currently present. Extrapolation of the model over the past million years demonstrates that the current "island archipelago" setting in Sundaland is extremely unusual given the majority of its history and the dramatic biogeographic transitions caused by global deglaciation were rapid and brief. Compared with dominant glacial conditions, lowland forests were probably reduced from approximately 1.3 to 0.8 x 10(6) km(2) while upland forests were probably reduced by half, from approximately 2.0 to 1.0 x 10(5) km(2). Coastal mangrove and swamp forests experienced the most dramatic change during deglaciations, going through a complete and major biogeographic relocation. The Sundaland forest dynamics of fragmentation and contraction and subsequent expansion, driven by glacial cycles, occur in the opposite phase as those in the northern hemisphere and equatorial Africa, indicating that Sundaland evergreen rainforest communities are currently in a refugial stage. Widespread human-mediated reduction and conversion of these forests in their refugial stage, when most species are passing through significant population bottlenecks, strongly emphasizes the urgency of conservation and management efforts. Further research into the natural process of fragmentation and contraction during deglaciation is necessary to understand the long-term effect of human activity on forest species.

Mangrove-Exported Nutrient Incorporation by Sessile Coral Reef Invertebrates

Coastal mangrove forests were historically considered as a source of organic matter (OM) for adjacent marine systems due to high net primary production; yet recent research suggesting little uptake through the food web because of low nutritional quality, challenges the concept of trophic linkage between mangrove forests and coral reefs. To examine the importance of mangrove forests to coral reef nutrient availability, we examined sessile reef-forming invertebrate consumers including hard corals, sponges, a bivalve mollusc, polychaete annelid and tunicate, and potential sources of OM (decaying mangrove leaves, microalgae, macroalgae, and seagrass) in Bocas del Toro, Panama. Using stable isotope analyses of δ34S and δ13C and a concentration-dependent version of the IsoSource mixing model, we were able to discriminate among and determine the range of potential contributions of our four OM sources to consumers. Contributions of microalgae and macroalgae were often indeterminate due to high variability, yet seagrass and mangrove contributions were often substantial. Mangrove OM ranged across sites and species of filter feeders from 0 to 57%, 7 to 41%, and 18 to 52% for sponges, file clams, and feather duster worms, respectively. Mangrove contribution to corals (Acropora cervicornis, Agaricia fragilis, Agaricia tenuifolia, Montastrea annularis, Diploria sp.) ranged from 0 to 44%. To examine whether OM contribution varied with distance from mangroves, we conducted a sponge transplant experiment that demonstrated declining mangrove contribution across three sponge species with increasing distance from the shore. These results supported the hypothesis of mangrove-coral reef nutrient linkages, providing the first evidence that mangrove inputs of OM to sessile invertebrates are substantial, accounting for 0–57% of the composition.

Influence of host-plant quality on the performance of Episimus unguiculus, a candidate biological control agent of Brazilian peppertree in Florida

Brazilian peppertree, Schinus terebinthifolius Raddi (Sapindales: Anacardiaceae), introduced from South America, invades a variety of habitats in Florida (e.g. disturbed sites, coastal mangrove forests). The objective of this study was to evaluate the effect of host-plant quality on the performance of Episimus unguiculus Clarke (=E. utilis Zimmerman) (Lepidoptera: Tortricidae), a potential biocontrol agent of Brazilian peppertree. Experiments were conducted in the laboratory using Brazilian peppertrees exposed either to different salinity levels (0, 6, 12 parts per thousand), or to different nutrient levels (low, medium, high). Higher survival (55%) and faster development (32 day) to adulthood was observed on plants grown in fresh-water environments (0 ppt) compared to low (6 ppt) or high-salinity environments (12 ppt). In addition, higher survival (40%), faster development (34 day) and higher fertility (88% eggs hatched) occurred in high-nutrient treatments. Based on these results, field releases should be conducted in favorable habitats (e.g., low salinity, high fertility soils) to maximize the possibility of establishment and population growth of E. unguiculus in Florida.