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Sample records for mangrove forest monitoring

  1. A review of uses of satellite imagery in monitoring mangrove forests

    NASA Astrophysics Data System (ADS)

    Rhyma Purnamasayangsukasih, P.; Norizah, K.; Ismail, Adnan A. M.; Shamsudin, I.

    2016-06-01

    Satellite image could provide much information of earth surfaces in a large scale in a short time, thus saving time. With the evolution and development of sensors providing satellite image, resolution of object captured enhanced with advance image processing techniques. In forestry, satellite image has been widely used for resources management, planning, monitoring, predicting, etc. However, the uses of satellite image are reported to be moderate and sometimes poor for mangrove forests due to homogenous species existed in salty and inundation areas. Many researches had been carried out to improve the uses of satellite imagery of either optical or radar data for mangrove forests. This paper reviews the uses of satellite imagery data in mangrove with the main focus of the literature related to mangroves monitoring.

  2. [Monitoring of the mangrove forest at Gandoca, Costa Rica (CARICOMP site)].

    PubMed

    Fonseca, Ana C; Cortés, Jorge; Zamora, Priscilla

    2007-03-01

    The mangrove forest at Gandoca, Refugio Nacional de Vida Silvestre Gandoca-Manzanillo, Caribbean coast of Costa Rica, has been monitored since 1999, following the CARICOMP protocol. The dominant species was the red mangrove, Rhizophora mangle. The peak of productivity and flowering was in July. The mangrove productivity decline from 2001 to 2004 while the temperature rised. Biomass (14 kg/m2) and density (9 trees/10 m2) in Gandoca were relatively low compared to other CARICOMP sites, while productivity in July in Costa Rica (4 g/m2/day) was intermediate, similar to most CARICOMP sites. PMID:18457111

  3. Applications of ALOS PALSAR for monitoring biophysical parameters of a degraded black mangrove (Avicennia germinans) forest

    NASA Astrophysics Data System (ADS)

    Kovacs, J. M.; Lu, X. X.; Flores-Verdugo, F.; Zhang, C.; Flores de Santiago, F.; Jiao, X.

    2013-08-01

    Within the last few decades mangrove forests worldwide have been experiencing high annual rates of loss and many of those that remain have undergone considerable degradation. To understand the condition of these forests, various optical remote sensing platforms have been used to map and monitor these wetlands, including the use of these data for biophysical parameter mapping. For many mangrove forests a reliable source of optical imagery is not possible given their location in quasi-permanent cloud cover or smoke covered regions. In such cases it is recommended that Synthetic Aperture Radar (SAR) be considered. The purpose of this investigation was to examine the relationships between various ALOS-PALSAR modes, acquired from eight images, and mangrove biophysical parameter data collected from a black mangrove (Avicennia germinans) dominated forest that has experienced considerable degradation. In total, structural data were collected from 61 plots representing the four common stand types found in this degraded forest of the Mexican Pacific: tall healthy mangrove (n = 17), dwarf healthy mangrove (n = 15), poor condition mangrove (n = 13), and predominantly dead mangrove (n = 16). Based on backscatter coefficients, significant negative correlation coefficients were observed between filtered single polarization ALOS PALSAR (6.25 m) HH backscatter and Leaf Area Index (LAI). When the dead stands were excluded (n = 45) the strength of these relationships increased. Moreover, significant negative correlation coefficients were observed with stand height, Basal Area (BA) and to a lesser degree with stem density and mean DBH. With the coarser spatial resolution dual-polarization and quad polarization data (12.5 m) only a few, and weaker, correlation coefficients were calculated between the mangrove parameters and the filtered HH backscatter. However, significant negative values were once again calculated for the HH when the 16 dead mangrove stands were removed from the

  4. Monitoring mangrove forest dynamics of the Sundarbans in Bangladesh and India using multi-temporal satellite data from 1973 to 2000

    NASA Astrophysics Data System (ADS)

    Giri, Chandra; Pengra, Bruce; Zhu, Zhiliang; Singh, Ashbindu; Tieszen, Larry L.

    2007-06-01

    Mangrove forests in many parts of the world are declining at an alarming rate—possibly even more rapidly than inland tropical forests. The rate and causes of such changes are not known. The forests themselves are dynamic in nature and are undergoing constant changes due to both natural and anthropogenic forces. Our research objective was to monitor deforestation and degradation arising from both natural and anthropogenic forces. We analyzed multi-temporal satellite data from 1970s, 1990s, and 2000s using supervised classification approach. Our spatio-temporal analysis shows that despite having the highest population density in the world in its periphery, areal extent of the mangrove forest of the Sundarbans has not changed significantly (approximately 1.2%) in the last ˜25 years. The forest is however constantly changing due to erosion, aggradation, deforestation and mangrove rehabilitation programs. The net forest area increased by 1.4% from the 1970s to 1990 and decreased by 2.5% from 1990 to 2000. The change is insignificant in the context of classification errors and the dynamic nature of mangrove forests. This is an excellent example of the co-existence of humans with terrestrial and aquatic plant and animal life. The strong commitment of governments under various protection measures such as forest reserves, wildlife sanctuaries, national parks, and international designations, is believed to be responsible for keeping this forest relatively intact (at least in terms of area). While the measured net loss of mangrove forest is not that high, the change matrix shows that turnover due to erosion, aggradation, reforestation and deforestation was much greater than net change. The forest is under threat from natural and anthropogenic forces leading to forest degradation, primarily due to top-dying disease and over-exploitation of forest resources.

  5. Monitoring mangrove forest dynamics of the Sundarbans in Bangladesh and India using multi-temporal satellite data from 1973 to 2000

    USGS Publications Warehouse

    Giri, C.; Pengra, B.; Zhu, Z.; Singh, A.; Tieszen, L.L.

    2007-01-01

    Mangrove forests in many parts of the world are declining at an alarming rate-possibly even more rapidly than inland tropical forests. The rate and causes of such changes are not known. The forests themselves are dynamic in nature and are undergoing constant changes due to both natural and anthropogenic forces. Our research objective was to monitor deforestation and degradation arising from both natural and anthropogenic forces. We analyzed multi-temporal satellite data from 1970s, 1990s, and 2000s using supervised classification approach. Our spatio-temporal??analysis shows that despite having the highest population density in the world in its periphery, areal extent of the mangrove forest of the Sundarbans has not changed significantly (approximately 1.2%) in the last ???25 years. The forest is however constantly changing due to erosion, aggradation, deforestation and mangrove rehabilitation programs. The net forest area increased by 1.4% from the 1970s to 1990 and decreased by 2.5% from 1990 to 2000. The change is insignificant in the context of classification errors and the dynamic nature of mangrove forests. This is an excellent example of the co-existence of humans with terrestrial and aquatic plant and animal life. The strong commitment of governments under various protection measures such as forest reserves, wildlife sanctuaries, national parks, and international designations, is believed to be responsible for keeping this forest relatively intact (at least in terms of area). While the measured net loss of mangrove forest is not that high, the change matrix shows that turnover due to erosion, aggradation, reforestation and deforestation was much greater than net change. The forest is under threat from natural and anthropogenic forces leading to forest degradation, primarily due to top-dying disease and over-exploitation of forest resources. ?? 2007 Elsevier Ltd. All rights reserved.

  6. Myanmar Ecological Forecasting: Utilizing NASA Earth Observations to Monitor, Map, and Analyze Mangrove Forests in Myanmar for Enhanced Conservation

    NASA Technical Reports Server (NTRS)

    Weber, Samuel J.; Keddell, Louis; Kemal, Mohammed

    2014-01-01

    Mangroves supply many essential environmental amenities, such as preventing soil erosion, filtering water pollution, and protecting shorelines from harmful waves, floods, storms and winds. The Mangroves in Myanmar not only provide citizens with a food source, but they also offer firewood, charcoal, and construction materials. The depletion of mangroves is threatening more than the biodiversity however; Myanmar's fiscal livelihood is also in harm's way. Mangroves are valued at $100,000 to $277,000 per square kilometer and if managed in a sustainable fashion, can infuse constant income to the emerging Myanmarese economy. This study analyzed three coastline regions, the Ayeyarwady Delta, Rakhine and Tanintharyi, and mapped the spatial extent of mangrove forest during the dry season in 2000 and 2013. The classifications were derived from Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 8 Operation Land Imager (OLI) imagery, as well as the Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation model information. This data was atmospherically corrected, mosaicked, masked and classified in ENVI, followed by ArcGIS to perform raster calculations and create final products. Forest degradation collected from 2000 to 2013 was later used to forecast the density and health of Mangroves in the year 2030. These results were subsequently presented to project partners Dr. Peter Leimgruber and Ellen Aiken at the Smithsonian Conservation Biology Institute in Front Royal, VA. After the presentation of the project to the partners, these organizations formally passed on to the Myanmar Ministry of Environment, Conservation and Forestry for policy makers and forest managers to utilize in order to protect the Myanmar mangrove ecosystem while sustaining a healthy economy.

  7. Stress in mangrove forests: Early detection and preemptive rehabilitation are essential for future successful worldwide mangrove forest management.

    PubMed

    Lewis, Roy R; Milbrandt, Eric C; Brown, Benjamin; Krauss, Ken W; Rovai, André S; Beever, James W; Flynn, Laura L

    2016-08-30

    Mangrove forest rehabilitation should begin much sooner than at the point of catastrophic loss. We describe the need for "mangrove forest heart attack prevention", and how that might be accomplished in a general sense by embedding plot and remote sensing monitoring within coastal management plans. The major cause of mangrove stress at many sites globally is often linked to reduced tidal flows and exchanges. Blocked water flows can reduce flushing not only from the seaward side, but also result in higher salinity and reduced sediments when flows are blocked landward. Long-term degradation of function leads to acute mortality prompted by acute events, but created by a systematic propensity for long-term neglect of mangroves. Often, mangroves are lost within a few years; however, vulnerability is re-set decades earlier when seemingly innocuous hydrological modifications are made (e.g., road construction, blocked tidal channels), but which remain undetected without reasonable large-scale monitoring. PMID:26971817

  8. Stress in mangrove forests: early detection and preemptive rehabilitation are essential for future successful worldwide mangrove forest management

    USGS Publications Warehouse

    Lewis, Roy R; Milbrandt, Eric C; Brown, Benjamin; Krauss, Ken W.; Rovai, Andre S; Beever, James W.; Flynn, Laura L

    2016-01-01

    Mangrove forest rehabilitation should begin much sooner than at the point of catastrophic loss. We describe the need for “mangrove forest heart attack prevention”, and how that might be accomplished in a general sense by embedding plot and remote sensing monitoring within coastal management plans. The major cause of mangrove stress at many sites globally is often linked to reduced tidal flows and exchanges. Blocked water flows can reduce flushing not only from the seaward side, but also result in higher salinity and reduced sediments when flows are blocked landward. Long-term degradation of function leads to acute mortality prompted by acute events, but created by a systematic propensity for long-term neglect of mangroves. Often, mangroves are lost within a few years; however, vulnerability is re-set decades earlier when seemingly innocuous hydrological modifications are made (e.g., road construction, blocked tidal channels), but which remain undetected without reasonable large-scale monitoring.

  9. Stress in mangrove forests: Early detection and preemptive rehabilitation are essential for future successful worldwide mangrove forest management.

    PubMed

    Lewis, Roy R; Milbrandt, Eric C; Brown, Benjamin; Krauss, Ken W; Rovai, André S; Beever, James W; Flynn, Laura L

    2016-08-30

    Mangrove forest rehabilitation should begin much sooner than at the point of catastrophic loss. We describe the need for "mangrove forest heart attack prevention", and how that might be accomplished in a general sense by embedding plot and remote sensing monitoring within coastal management plans. The major cause of mangrove stress at many sites globally is often linked to reduced tidal flows and exchanges. Blocked water flows can reduce flushing not only from the seaward side, but also result in higher salinity and reduced sediments when flows are blocked landward. Long-term degradation of function leads to acute mortality prompted by acute events, but created by a systematic propensity for long-term neglect of mangroves. Often, mangroves are lost within a few years; however, vulnerability is re-set decades earlier when seemingly innocuous hydrological modifications are made (e.g., road construction, blocked tidal channels), but which remain undetected without reasonable large-scale monitoring.

  10. Mangrove Forest Distributions and Dynamics in Madagascar (1975–2005)

    PubMed Central

    Giri, Chandra; Muhlhausen, Joseph

    2008-01-01

    Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of ± one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ∼2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%).

  11. Mangrove forest distributions and dynamics in Madagascar (1975-2005)

    USGS Publications Warehouse

    Giri, C.; Muhlhausen, J.

    2008-01-01

    Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of ?? one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ???2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km 2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%). ?? 2008 by MDPI.

  12. Soil Respiration of Three Mangrove Forests on Sanibel Island, Florida

    NASA Astrophysics Data System (ADS)

    Cartwright, F.; Bovard, B. D.

    2011-12-01

    Carbon cycling studies conducted in mangrove forests have typically focused on aboveground processes. Our understanding of carbon storage in these systems is therefore limited by the lack information on belowground processes such as fine root production and soil respiration. To our knowledge there exist no studies investigating temporal patterns in and environmental controls on soil respiration in multiple types of mangrove ecosystems concurrently. This study is part of a larger study on carbon storage in three mangrove forests on Sanibel Island, Florida. Here we report on eight months of soil respiration data within these forests that will ultimately be incorporated into an annual carbon budget for each habitat type. Soil respiration was monitored in the following three mangrove habitat types: a fringe mangrove forest dominated by Rhizophora mangle, a basin mangrove forest dominated by Avicennia germinans, and a higher elevation forest comprised of a mix of Avicennia germinans and Laguncularia racemosa, and non-woody salt marsh species. Beginning in June of 2010, we measured soil emissions of carbon dioxide at 5 random locations within three-100 m2 plots within each habitat type. Sampling was performed at monthly intervals and conducted over the course of three days. For each day, one plot from each habitat type was measured. In addition to soil respiration, soil temperature, salinity and gravimetric moisture content were also measured. Our data indicate the Black mangrove forest, dominated by Avicennia germinans, experiences the highest rates of soil respiration with a mean rate of 4.61 ± 0.60 μmol CO2 m-2 s-1. The mixed mangrove and salt marsh habitat has the lowest soil carbon emission rates with a mean of 2.78 ± 0.40 μmol CO2 m-2 s-1. Soil carbon effluxes appear to peak in the early part of the wet season around May to June and are lower and relatively constant the remainder of the year. Our data also suggest there are important but brief periods where

  13. Coastal mangrove forests mitigated tsunami

    NASA Astrophysics Data System (ADS)

    Kathiresan, Kandasamy; Rajendran, Narayanasamy

    2005-11-01

    A study conducted after the 26th of December 2004 tsunami in 18 coastal hamlets along the south-east coast of India reiterates the importance of coastal mangrove vegetations and location characteristics of human inhabitation to protect lives and wealth from the fury of tsunami. The tsunami caused human death and loss of wealth and these decreased with the area of coastal vegetation, distance and elevation of human inhabitation from the sea. Human inhabitation should be encouraged more than 1 km from the shoreline in elevated places, behind dense mangroves and or other coastal vegetation. Some plant species, suitable to grow in between human inhabitation and the sea for coastal protection, are suggested.

  14. Carbon Cycling and Storage in Mangrove Forests

    NASA Astrophysics Data System (ADS)

    Alongi, Daniel M.

    2014-01-01

    Mangroves are ecologically and economically important forests of the tropics. They are highly productive ecosystems with rates of primary production equal to those of tropical humid evergreen forests and coral reefs. Although mangroves occupy only 0.5% of the global coastal area, they contribute 10-15% (24 Tg C y-1) to coastal sediment carbon storage and export 10-11% of the particulate terrestrial carbon to the ocean. Their disproportionate contribution to carbon sequestration is now perceived as a means for conservation and restoration and a way to help ameliorate greenhouse gas emissions. Of immediate concern are potential carbon losses to deforestation (90-970 Tg C y-1) that are greater than these ecosystems' rates of carbon storage. Large reservoirs of dissolved inorganic carbon in deep soils, pumped via subsurface pathways to adjacent waterways, are a large loss of carbon, at a potential rate up to 40% of annual primary production. Patterns of carbon allocation and rates of carbon flux in mangrove forests are nearly identical to those of other tropical forests.

  15. Carbon cycling and storage in mangrove forests.

    PubMed

    Alongi, Daniel M

    2014-01-01

    Mangroves are ecologically and economically important forests of the tropics. They are highly productive ecosystems with rates of primary production equal to those of tropical humid evergreen forests and coral reefs. Although mangroves occupy only 0.5% of the global coastal area, they contribute 10-15% (24 Tg C y(-1)) to coastal sediment carbon storage and export 10-11% of the particulate terrestrial carbon to the ocean. Their disproportionate contribution to carbon sequestration is now perceived as a means for conservation and restoration and a way to help ameliorate greenhouse gas emissions. Of immediate concern are potential carbon losses to deforestation (90-970 Tg C y(-1)) that are greater than these ecosystems' rates of carbon storage. Large reservoirs of dissolved inorganic carbon in deep soils, pumped via subsurface pathways to adjacent waterways, are a large loss of carbon, at a potential rate up to 40% of annual primary production. Patterns of carbon allocation and rates of carbon flux in mangrove forests are nearly identical to those of other tropical forests. PMID:24405426

  16. Global trends and vulnerabilities of mangrove forests

    NASA Astrophysics Data System (ADS)

    Simard, M.; Fatoyinbo, T. E.; Rivera-Monroy, V. H.; Castaneda, E.; Roy Chowdhury, R.

    2015-12-01

    Mangrove forests are located along Earth's coastlines and estuaries within tropical and subtropical latitudes. They provide numerous services functioning as an extraordinary carbon sequestration system and serving as habitat and nursery for fish, crustaceans and amphibians. To coastal populations, they provide livelihood, food, lumber and act as an effective protection against tsunamis, storm surges and hurricanes. Their vulnerability to sea level rise is strongly related to their extraordinary ability to accumulate soils, which is in part related to their productivity and therefore canopy structure. As a first step to understand their vulnerability, we seek to understand mangrove dependencies on environmental and geophysical setting. To achieve this, we mapped mangrove canopy height and above ground biomass (AGB) at the Global scale. To identify mangrove forests, existing maps derived from a collection of Landsat data around the 2000 era were used. Using the Shuttle Radar Topography Mission elevation data collected in February of 2000, we produced a Global map of mangrove canopy height. The estimated heights were validated with the ICESat/Geoscience Altimeter System (GLAS) and in situ field data. Most importantly, field data were also used to derive relationships between canopy height and AGB. While the geographical coverage of in situ data is limited, ICESat/GLAS data provided extensive geographical coverage with independent estimates of maximum canopy height. These estimates were used to calibrate SRTM-estimates of height at the Global scale. We found the difference between GLAS RH100 and SRTM resulted from several sources of uncertainty that are difficult to isolate. These include natural variations of canopy structure with time, system errors from GLAS and SRTM, geo-location errors and discrepancies in spatial resolution. The Global canopy height map was trnasormed into AGB using the field-derived allometry. Depending on the scale of analysis and geographical

  17. Predicting future mangrove forest migration in the Everglades under rising sea level

    USGS Publications Warehouse

    Doyle, Thomas W.

    2003-01-01

    Mangroves are highly productive ecosystems that provide valued habitat for fish and shorebirds. Mangrove forests are universally composed of relatively few tree species and a single overstory strata. Three species of true mangroves are common to intertidal zones of the Caribbean and Gulf of Mexico Coast, namely, black mangrove (Avicennia germinans), white mangrove (Laguncularia racemosa), and red mangrove (Rhizophora mangle). Mangrove forests occupy intertidal settings of the coastal margin of the Everglades along the southwest tip of the Florida peninsula (fig. 1).

  18. Restoration of biogeochemical function in mangrove forests

    USGS Publications Warehouse

    McKee, K.L.; Faulkner, P.L.

    2000-01-01

    Forest structure of mangrove restoration sites (6 and 14 years old) at two locations (Henderson Creek [HC] and Windstar [WS]) in southwest Florida differed from that of mixed-basin forests (>50 years old) with which they were once contiguous. However, the younger site (HC) was typical of natural, developing forests, whereas the older site (WS) was less well developed with low structural complexity. More stressful physicochemical conditions resulting from incomplete tidal flushing (elevated salinity) and variable topography (waterlogging) apparently affected plant survival and growth at the WS restoration site. Lower leaf fall and root production rates at the WS restoration site, compared with that at HC were partly attributable to differences in hydroedaphic conditions and structural development. However, leaf and root inputs at each restoration site were not significantly different from that in reference forests within the same physiographic setting. Macrofaunal consumption of tethered leaves also did not differ with site history, but was dramatically higher at HC compared with WS, reflecting local variation in leaf litter processing rates, primarily by snails (Melampus coffeus). Degradation of leaves and roots in mesh bags was slow overall at restoration sites, however, particularly at WS where aerobic decomposition may have been more limited. These findings indicate that local or regional factors such as salinity regime act together with site history to control primary production and turnover rates of organic matter in restoration sites. Species differences in senescent leaf nitrogen content and degradation rates further suggest that restoration sites dominated by Laguncularia racemosa and Rhizophora mangle should exhibit slower recycling of nutrients compared with natural basin forests where Avicennia germinans is more abundant. Structural development and biogeochemical functioning of restored mangrove forests thus depend on a number of factors, but site

  19. Floods and mangrove forests, friends or foes? Perceptions of relationships and risks in Cameroon coastal mangroves

    NASA Astrophysics Data System (ADS)

    Munji, Cecilia A.; Bele, Mekou Y.; Idinoba, Monica E.; Sonwa, Denis J.

    2014-03-01

    Faced with the growing influence of climate change on climate driven perturbations such as flooding and biodiversity loss, managing the relationship between mangroves and their environment has become imperative for their protection. Hampering this is the fact that the full scope of the threats faced by specific mangrove forests is not yet well documented. Amongst some uncertainties is the nature of the relationship/interaction of mangroves with climate driven perturbations prevalent in their habitat such as coastal floods. We investigated the relationship between coastal flooding and mangrove forest stabilization, identify perceptions of flood risk and responses to offset identified effects. Random household surveys were carried out within four communities purposively sampled within the Cap Cameroon. Coastal changes were investigated over a period of 43 years (1965-2008). Seasonal flooding improved access to mangrove forests and hence promoted their exploitation for non-timber forest products (NTFPs) such as fuel wood and mangrove poles. 989 ha of mangrove forests were estimated to be lost over a period of 43 years in Cap Cameroon with implications on forest resources base, ecosystem stability, and livelihoods. Alternative livelihood activities were found to be carried out to moderate interruptions in fishing, with associated implications for mangrove forest dynamics. Respondents were of the opinion that risks associated with floods and mangrove deforestation will pose a major challenge for sustainable management of mangroves. These locally relevant perceptions and responses should however enable the identification of pertinent needs, challenges and opportunities to inform and orient effective decision-making, and to facilitate the development and participation in adaptive management strategies.

  20. Downed wood in Micronesian mangrove forests

    USGS Publications Warehouse

    Allen, J.A.; Ewel, K.C.; Keeland, B.D.; Tara, T.; Smith, T. J.

    2000-01-01

    Dead, downed wood is an important component of upland forest and aquatic ecosystems, but its role in wetland ecosystems, including mangroves, is poorly understood. We measured downed wood in ten sites on the western Pacific islands of Kosrae, Pohnpei, and Yap, all located within the Federated States of Micronesia. Our goals were to examine patterns of variability in the quantity of downed wood in these mangrove ecosystems, provide a general characterization of downed wood in a region with no previously published accounts, and investigate the relationship between harvesting practices and the amount of downed wood. The overall mean volume of downed wood at our study sites was estimated to be 60.8 m3 ha-1 (20.9 t ha-1), which is greater than most published data for forested wetlands. There were significant differences among islands, with the sites on Kosrae (104.2 m3 ha-1) having a much greater mean volume of downed wood than those on Pohnpei (43.1 m3 ha-1) or Yap (35.1 m3 ha-1). Part of the difference among islands may be attributable to differences in stand age and structure, but the most important factor seems to be the greater amount of wood harvesting on Kosrae, coupled with a low efficiency of use of cut trees. Of a total of 45 cut trees examined on Kosrae, no wood had been removed from 18 (40%); these are believed to be trees cut down because other, more valuable, trees were caught on them as they were felled. Of the other 27 trees, only 24 to 42% of the stem volume (to a 10 cm top) was removed from the forest, the amount varying by species. The impacts of current harvesting practices are unknown but may include important effects on tree regeneration and the abundance and species composition of crab populations.

  1. Measuring surface energy and evapotranspiration across Caribbean mangrove forests

    NASA Astrophysics Data System (ADS)

    Lagomasino, D.; Fatoyinbo, T. E.; Price, R.

    2014-12-01

    Coastal mangroves lose large amounts of water through evapotranspiration (ET) that can be equivalent to the amount of annual rainfall in certain years. Satellite remote sensing has been used to estimate surface energy and ET variability in many forested ecosystems, yet has been widely overlooked in mangrove forests. Using a combination of long-term datasets (30-year) acquired from the NASA Landsat 5 and 7 satellite databases, the present study investigated ET and surface energy balance variability between two mangrove forest sites in the Caribbean: 1) Everglades National Park (ENP; Florida, USA) and 2) Sian Ka'an Biosphere Reserve (SKBR; Quintana Roo, Mexico). A satellite-derived surface energy balance model was used to estimate ET in tall and scrub mangroves environments at ENP and SKBR. Results identified significant differences in soil heat flux measurements and ET between the tall and scrub mangrove environments. Scrub mangroves exhibited the highest soil heat flux coincident with the lowest biophysical indices (i.e., Fractional Vegetation Cover, Normalized Difference Vegetation Index, and Soil-Adjusted Vegetation Index) and ET rates. Mangrove damage and mortality was observed on the satellite images following strong tropical storms and associated with anthropogenic modifications and resulted in low values in spectral vegetation indices, higher soil heat flux, and higher ET. Recovery of the spectral characteristics, soil heat flux and ET was within 1-2 years following hurricane disturbance while, degradation caused by human disturbance persisted for many years. Remotely sensed ET of mangrove forests can provide estimates over a few decades and provide us with some understanding of how these environments respond to disturbances to the landscape in periods where no ground data exists or in locations that are difficult to access. Moreover, relationships between energy and water balance components developed for the coastal mangroves of Florida and Mexico could be

  2. Mapping the Philippines’ Mangrove Forests Using Landsat Imagery

    PubMed Central

    Long, Jordan B.; Giri, Chandra

    2011-01-01

    Current, accurate, and reliable information on the areal extent and spatial distribution of mangrove forests in the Philippines is limited. Previous estimates of mangrove extent do not illustrate the spatial distribution for the entire country. This study, part of a global assessment of mangrove dynamics, mapped the spatial distribution and areal extent of the Philippines’ mangroves circa 2000. We used publicly available Landsat data acquired primarily from the Global Land Survey to map the total extent and spatial distribution. ISODATA clustering, an unsupervised classification technique, was applied to 61 Landsat images. Statistical analysis indicates the total area of mangrove forest cover was approximately 256,185 hectares circa 2000 with overall classification accuracy of 96.6% and a kappa coefficient of 0.926. These results differ substantially from most recent estimates of mangrove area in the Philippines. The results of this study may assist the decision making processes for rehabilitation and conservation efforts that are currently needed to protect and restore the Philippines’ degraded mangrove forests. PMID:22163779

  3. Mapping the Philippines' mangrove forests using Landsat imagery.

    PubMed

    Long, Jordan B; Giri, Chandra

    2011-01-01

    Current, accurate, and reliable information on the areal extent and spatial distribution of mangrove forests in the Philippines is limited. Previous estimates of mangrove extent do not illustrate the spatial distribution for the entire country. This study, part of a global assessment of mangrove dynamics, mapped the spatial distribution and areal extent of the Philippines' mangroves circa 2000. We used publicly available Landsat data acquired primarily from the Global Land Survey to map the total extent and spatial distribution. ISODATA clustering, an unsupervised classification technique, was applied to 61 Landsat images. Statistical analysis indicates the total area of mangrove forest cover was approximately 256,185 hectares circa 2000 with overall classification accuracy of 96.6% and a kappa coefficient of 0.926. These results differ substantially from most recent estimates of mangrove area in the Philippines. The results of this study may assist the decision making processes for rehabilitation and conservation efforts that are currently needed to protect and restore the Philippines' degraded mangrove forests. PMID:22163779

  4. Mapping the Philippines' mangrove forests using Landsat imagery

    USGS Publications Warehouse

    Long, J.B.; Giri, C.

    2011-01-01

    Current, accurate, and reliable information on the areal extent and spatial distribution of mangrove forests in the Philippines is limited. Previous estimates of mangrove extent do not illustrate the spatial distribution for the entire country. This study, part of a global assessment of mangrove dynamics, mapped the spatial distribution and areal extent of the Philippines' mangroves circa 2000. We used publicly available Landsat data acquired primarily from the Global Land Survey to map the total extent and spatial distribution. ISODATA clustering, an unsupervised classification technique, was applied to 61 Landsat images. Statistical analysis indicates the total area of mangrove forest cover was approximately 256,185 hectares circa 2000 with overall classification accuracy of 96.6% and a kappa coefficient of 0.926. These results differ substantially from most recent estimates of mangrove area in the Philippines. The results of this study may assist the decision making processes for rehabilitation and conservation efforts that are currently needed to protect and restore the Philippines' degraded mangrove forests. ?? 2011 by the authors; licensee MDPI, Basel, Switzerland.

  5. Cage experiments in an East African mangrove forest: a synthesis

    NASA Astrophysics Data System (ADS)

    Schrijvers, J.; Vincx, M.

    1997-12-01

    The impact of epibenthos on endobenthos has frequently been investigated for temperate saltmarsh regions by using cage exclusion experiments. Although the insight into the function of the endobenthos of mangrove forests is crucial for their management, very few cage experiments have so far been carried out in such areas. The present paper summaries the results of such experiments in a typical East African mangrove forest at Gazi Bay about 60 km south of Mombasa, Kenya. Epibenthic animals were excluded for one year in two mangrove zones which differed in forest morphology and intertidal position ( Ceriops tagal and Avicennia marina). Environmental factors and meiobenthic and macrobenthic densities were followed in a randomised block design, and procedural and exclusion effects were statistically detected. In confronting the separate responses of all faunal groups in the two mangrove zones, this synthesis gives a better insight into the tropho-dynamical interactions than the earlier separate reports on the same experiment. The ecosystem of the mangrove zones and the competitive interactions within this system provided an ideal opportunity to discover the existence of two food systems. This confirmed a strong involvement of the majority of the endobenthos in an isolated decompositional pathway in the mangrove sediment. It became clear that this exploitative competition was more important than the epibenthic predation in structuring and regulating the global endobenthic community. This synthesis therefore both demonstrates the decisive role of the endobenthos as regenators of mangrove material, and suggests that endobenthos plays a minor role as prey for the demersal or pelagic carnivores.

  6. Distribution and dynamics of mangrove forests of South Asia.

    PubMed

    Giri, Chandra; Long, Jordan; Abbas, Sawaid; Murali, R Mani; Qamer, Faisal M; Pengra, Bruce; Thau, David

    2015-01-15

    Mangrove forests in South Asia occur along the tidal sea edge of Bangladesh, India, Pakistan, and Sri Lanka. These forests provide important ecosystem goods and services to the region's dense coastal populations and support important functions of the biosphere. Mangroves are under threat from both natural and anthropogenic stressors; however the current status and dynamics of the region's mangroves are poorly understood. We mapped the current extent of mangrove forests in South Asia and identified mangrove forest cover change (gain and loss) from 2000 to 2012 using Landsat satellite data. We also conducted three case studies in Indus Delta (Pakistan), Goa (India), and Sundarbans (Bangladesh and India) to identify rates, patterns, and causes of change in greater spatial and thematic details compared to regional assessment of mangrove forests. Our findings revealed that the areal extent of mangrove forests in South Asia is approximately 1,187,476 ha representing ∼7% of the global total. Our results showed that from 2000 to 2012, 92,135 ha of mangroves were deforested and 80,461 ha were reforested with a net loss of 11,673 ha. In all three case studies, mangrove areas have remained the same or increased slightly, however, the turnover was greater than the net change. Both, natural and anthropogenic factors are responsible for the change and turnover. The major causes of forest cover change are similar throughout the region; however, specific factors may be dominant in specific areas. Major causes of deforestation in South Asia include (i) conversion to other land use (e.g. conversion to agriculture, shrimp farms, development, and human settlement), (ii) over-harvesting (e.g. grazing, browsing and lopping, and fishing), (iii) pollution, (iv) decline in freshwater availability, (v) floodings, (vi) reduction of silt deposition, (vii) coastal erosion, and (viii) disturbances from tropical cyclones and tsunamis. Our analysis in the region's diverse socio-economic and

  7. Distribution and dynamics of mangrove forests of South Asia.

    PubMed

    Giri, Chandra; Long, Jordan; Abbas, Sawaid; Murali, R Mani; Qamer, Faisal M; Pengra, Bruce; Thau, David

    2015-01-15

    Mangrove forests in South Asia occur along the tidal sea edge of Bangladesh, India, Pakistan, and Sri Lanka. These forests provide important ecosystem goods and services to the region's dense coastal populations and support important functions of the biosphere. Mangroves are under threat from both natural and anthropogenic stressors; however the current status and dynamics of the region's mangroves are poorly understood. We mapped the current extent of mangrove forests in South Asia and identified mangrove forest cover change (gain and loss) from 2000 to 2012 using Landsat satellite data. We also conducted three case studies in Indus Delta (Pakistan), Goa (India), and Sundarbans (Bangladesh and India) to identify rates, patterns, and causes of change in greater spatial and thematic details compared to regional assessment of mangrove forests. Our findings revealed that the areal extent of mangrove forests in South Asia is approximately 1,187,476 ha representing ∼7% of the global total. Our results showed that from 2000 to 2012, 92,135 ha of mangroves were deforested and 80,461 ha were reforested with a net loss of 11,673 ha. In all three case studies, mangrove areas have remained the same or increased slightly, however, the turnover was greater than the net change. Both, natural and anthropogenic factors are responsible for the change and turnover. The major causes of forest cover change are similar throughout the region; however, specific factors may be dominant in specific areas. Major causes of deforestation in South Asia include (i) conversion to other land use (e.g. conversion to agriculture, shrimp farms, development, and human settlement), (ii) over-harvesting (e.g. grazing, browsing and lopping, and fishing), (iii) pollution, (iv) decline in freshwater availability, (v) floodings, (vi) reduction of silt deposition, (vii) coastal erosion, and (viii) disturbances from tropical cyclones and tsunamis. Our analysis in the region's diverse socio-economic and

  8. Organic carbon inventories in natural and restored Ecuadorian mangrove forests.

    PubMed

    DelVecchia, Amanda G; Bruno, John F; Benninger, Larry; Alperin, Marc; Banerjee, Ovik; de Dios Morales, Juan

    2014-01-01

    Mangroves can capture and store organic carbon and their protection and therefore their restoration is a component of climate change mitigation. However, there are few empirical measurements of long-term carbon storage in mangroves or of how storage varies across environmental gradients. The context dependency of this process combined with geographically limited field sampling has made it difficult to generalize regional and global rates of mangrove carbon sequestration. This has in turn hampered the inclusion of sequestration by mangroves in carbon cycle models and in carbon offset markets. The purpose of this study was to estimate the relative carbon capture and storage potential in natural and restored mangrove forests. We measured depth profiles of soil organic carbon content in 72 cores collected from six sites (three natural, two restored, and one afforested) surrounding Muisne, Ecuador. Samples up to 1 m deep were analyzed for organic matter content using loss-on-ignition and values were converted to organic carbon content using an accepted ratio of 1.72 (g/g). Results suggest that average soil carbon storage is 0.055 ± 0.002 g cm(-3) (11.3 ± 0.8% carbon content by dry mass, mean ± 1 SE) up to 1 m deep in natural sites, and 0.058 ± 0.002 g cm(-3) (8.0 ± 0.3%) in restored sites. These estimates are concordant with published global averages. Evidence of equivalent carbon stocks in restored and afforested mangrove patches emphasizes the carbon sink potential for reestablished mangrove systems. We found no relationship between sediment carbon storage and aboveground biomass, forest structure, or within-patch location. Our results demonstrate the long-term carbon storage potential of natural mangroves, high effectiveness of mangrove restoration and afforestation, a lack of predictability in carbon storage strictly based on aboveground parameters, and the need to establish standardized protocol for quantifying mangrove sediment carbon stocks. PMID:24883249

  9. Organic carbon inventories in natural and restored Ecuadorian mangrove forests

    PubMed Central

    Bruno, John F.; Benninger, Larry; Alperin, Marc; de Dios Morales, Juan

    2014-01-01

    Mangroves can capture and store organic carbon and their protection and therefore their restoration is a component of climate change mitigation. However, there are few empirical measurements of long-term carbon storage in mangroves or of how storage varies across environmental gradients. The context dependency of this process combined with geographically limited field sampling has made it difficult to generalize regional and global rates of mangrove carbon sequestration. This has in turn hampered the inclusion of sequestration by mangroves in carbon cycle models and in carbon offset markets. The purpose of this study was to estimate the relative carbon capture and storage potential in natural and restored mangrove forests. We measured depth profiles of soil organic carbon content in 72 cores collected from six sites (three natural, two restored, and one afforested) surrounding Muisne, Ecuador. Samples up to 1 m deep were analyzed for organic matter content using loss-on-ignition and values were converted to organic carbon content using an accepted ratio of 1.72 (g/g). Results suggest that average soil carbon storage is 0.055 ± 0.002 g cm−3 (11.3 ± 0.8% carbon content by dry mass, mean ± 1 SE) up to 1 m deep in natural sites, and 0.058 ± 0.002 g cm−3 (8.0 ± 0.3%) in restored sites. These estimates are concordant with published global averages. Evidence of equivalent carbon stocks in restored and afforested mangrove patches emphasizes the carbon sink potential for reestablished mangrove systems. We found no relationship between sediment carbon storage and aboveground biomass, forest structure, or within-patch location. Our results demonstrate the long-term carbon storage potential of natural mangroves, high effectiveness of mangrove restoration and afforestation, a lack of predictability in carbon storage strictly based on aboveground parameters, and the need to establish standardized protocol for quantifying mangrove sediment carbon stocks. PMID:24883249

  10. Evaluating the condition of a mangrove forest of the Mexican Pacific based on an estimated leaf area index mapping approach.

    PubMed

    Kovacs, J M; King, J M L; Flores de Santiago, F; Flores-Verdugo, F

    2009-10-01

    mangrove, mean estimated LAI values of 4.66 and 2.39 were calculated, respectively. Given that the former healthy group only represents 8% of the total mangrove area examined, it is concluded that this mangrove system, considered one of the most important of the Pacific coast of the Americas, is currently experiencing a considerable state of degradation. Furthermore, based on the results of this investigation it is suggested that this approach could provide resource managers and scientists alike with a very rapid and effective method for monitoring the state of remaining mangrove forests of the Mexican Pacific and, possibly, other areas of the tropics. PMID:19023672

  11. Evaluating the condition of a mangrove forest of the Mexican Pacific based on an estimated leaf area index mapping approach.

    PubMed

    Kovacs, J M; King, J M L; Flores de Santiago, F; Flores-Verdugo, F

    2009-10-01

    mangrove, mean estimated LAI values of 4.66 and 2.39 were calculated, respectively. Given that the former healthy group only represents 8% of the total mangrove area examined, it is concluded that this mangrove system, considered one of the most important of the Pacific coast of the Americas, is currently experiencing a considerable state of degradation. Furthermore, based on the results of this investigation it is suggested that this approach could provide resource managers and scientists alike with a very rapid and effective method for monitoring the state of remaining mangrove forests of the Mexican Pacific and, possibly, other areas of the tropics.

  12. Mangrove forest recovery in the Everglades following Hurricane Wilma

    USGS Publications Warehouse

    Sarmiento, Daniel; Barr, Jordan; Engel, Vic; Fuentes, Jose D.; Smith, Thomas J.; Zieman, Jay C.

    2009-01-01

    On October 24th, 2005, Hurricane Wilma made landfall on the south western shore of the Florida peninsula. This major disturbance destroyed approximately 30 percent of the mangrove forests in the area. However, the damage to the ecosystem following the hurricane provided researchers at the Florida Coastal Everglades (FCE) LTER site with the rare opportunity to track the recovery process of the mangroves as determined by carbon dioxide (CO2) and energy exchanges, measured along daily and seasonal time scales.

  13. Hydrological classification of mangrove forests: a tool for successful mangrove rehabilitation

    NASA Astrophysics Data System (ADS)

    van Huijgevoort, Marjolein; van Loon, Anne; te Brake, Bram; Dijksma, Roel

    2015-04-01

    Mangrove forests are very valuable for coastal protection, ecosystem functioning and supporting livelihoods of coastal communities. Nevertheless, the size, number and ecological quality of mangrove forests are declining worldwide due to human influence like logging, aquaculture, and coastal development. To restore mangrove forests, rehabilitation projects are necessary. Unfortunately, many of these projects fail, because the hydrological conditions are not taken into account. This is understandable because hydrological conditions in mangrove forests are highly variable in time and space. To increase the success rate of rehabilitation projects a hydrological classification, which links hydrological site characteristics, such as inundation duration, to common mangrove species, could be a useful tool. This study investigates the potential of such a classification at a number of locations with natural and disturbed hydrological conditions. The hydrological classification has been developed from field data of two natural sites in Vietnam based on an existing classification (Watson, 1928). For all sites, data of water levels in the open water and at various locations across the mangrove forest were collected, and the vegetation composition at the measurement locations was determined during various field campaigns. From the water level data, the tidal regime, tidal frequency, and duration of inundation in minutes per day and minutes per inundation were derived. Testing has shown that, because of the irregular tidal regime and the effect of stagnant water due to (micro-)topography, tidal regime and frequency are not representative for the hydrological conditions determining mangrove species distribution. Duration of inundation in minutes per day and minutes per inundation are, however, both crucial factors for mangrove zonation and are therefore essential in a hydrological classification for mangroves. Six distinct classes were distinguished that are linked to the

  14. Determination of mangrove change in Matang Mangrove Forest using multi temporal satellite imageries

    NASA Astrophysics Data System (ADS)

    Ibrahim, N. A.; Mustapha, M. A.; Lihan, T.; Ghaffar, M. A.

    2013-11-01

    Mangrove protects shorelines from damaging storm and hurricane winds, waves, and floods. Mangroves also help prevent erosion by stabilizing sediments with their tangled root systems. They maintain water quality and clarity, filtering pollutants and trapping sediments originating from land. However, mangrove has been reported to be threatened by land conversion for other activities. In this study, land use and land cover changes in Matang Mangrove Forest during the past 18 years (1993 to 2011) were determined using multi-temporal satellite imageries by Landsat TM and RapidEye. In this study, classification of land use and land cover approach was performed using the maximum likelihood classifier (MCL) method along with vegetation index differencing (NDVI) technique. Data obtained was evaluated through Kappa coefficient calculation for accuracy and results revealed that the classification accuracy was 81.25% with Kappa Statistics of 0.78. The results indicated changes in mangrove forest area to water body with 2,490.6 ha, aquaculture with 890.7 ha, horticulture with 1,646.1 ha, palm oil areas with 1,959.2 ha, dry land forest with 2,906.7 ha and urban settlement area with 224.1 ha. Combinations of these approaches were useful for change detection and for indication of the nature of these changes.

  15. Remote Characterization of Biomass Measurements: Case Study of Mangrove Forests

    NASA Technical Reports Server (NTRS)

    Fatoyinbo, Temilola E.

    2010-01-01

    Accurately quantifying forest biomass is of crucial importance for climate change studies. By quantifying the amount of above and below ground biomass and consequently carbon stored in forest ecosystems, we are able to derive estimates of carbon sequestration, emission and storage and help close the carbon budget. Mangrove forests, in addition to providing habitat and nursery grounds for over 1300 animal species, are also an important sink of biomass. Although they only constitute about 3% of the total forested area globally, their carbon storage capacity -- in forested biomass and soil carbon -- is greater than that of tropical forests (Lucas et al, 2007). In addition, the amount of mangrove carbon -- in the form of litter and leaves exported into offshore areas is immense, resulting in over 10% of the ocean's dissolved organic carbon originating from mangroves (Dittmar et al, 2006) The measurement of forest above ground biomass is carried out on two major scales: on the plot scale, biomass can be measured using field measurements through allometric equation derivation and measurements of forest plots. On the larger scale, the field data are used to calibrate remotely sensed data to obtain stand-wide or even regional estimates of biomass. Currently, biomass can be calculated using average stand biomass values and optical data, such as aerial photography or satellite images (Landsat, Modis, Ikonos, SPOT, etc.). More recent studies have concentrated on deriving forest biomass values using radar (JERS, SIR-C, SRTM, Airsar) and/or lidar (ICEsat/GLAS, LVIS) active remote sensing to retrieve more accurate and detailed measurements of forest biomass. The implementation of a generation of new active sensors (UAVSar, DesdynI, Alos/Palsar, TerraX) has prompted the development of new tecm'liques of biomass estimation that use the combination of multiple sensors and datasets, to quantify past, current and future biomass stocks. Focusing on mangrove forest biomass estimation

  16. Mosquitoes of the mangrove forests of India: part 2--Sundarbans, West Bengal.

    PubMed

    Rajavel, A R; Natarajan, R; Vaidyanathan, K

    2005-06-01

    Mosquitoes of 19 species belonging to 9 subgenera and 6 genera, Aedes, Aedeomyia, Anopheles, Armigeres, Culex, and Mansonia, were recorded in Sundarbans mangrove forest in West Bengal, India. With 6 and 5 species, respectively, the 2 genera Culex and Anopheles were found to be more diverse while less than 3 species were recorded in the other 4 genera. Adults were mainly collected resting on walls in the guesthouse, tree holes in the forest, landing on humans in the guesthouse, and in the forest, and in light traps. Larvae were obtained from tree holes in the forest. The list of species recorded is not conclusive due to the restriction in access to most parts of the mangroves due to the presence of tigers. The occurrence of the urban species Cx. quinquefasciatus within the Sajnakhali sanctuary is indicative of the need to monitor environmental changes that result with the introduction of man-made facilities.

  17. Mosquitoes of the mangrove forests of India: part 2--Sundarbans, West Bengal.

    PubMed

    Rajavel, A R; Natarajan, R; Vaidyanathan, K

    2005-06-01

    Mosquitoes of 19 species belonging to 9 subgenera and 6 genera, Aedes, Aedeomyia, Anopheles, Armigeres, Culex, and Mansonia, were recorded in Sundarbans mangrove forest in West Bengal, India. With 6 and 5 species, respectively, the 2 genera Culex and Anopheles were found to be more diverse while less than 3 species were recorded in the other 4 genera. Adults were mainly collected resting on walls in the guesthouse, tree holes in the forest, landing on humans in the guesthouse, and in the forest, and in light traps. Larvae were obtained from tree holes in the forest. The list of species recorded is not conclusive due to the restriction in access to most parts of the mangroves due to the presence of tigers. The occurrence of the urban species Cx. quinquefasciatus within the Sajnakhali sanctuary is indicative of the need to monitor environmental changes that result with the introduction of man-made facilities. PMID:16033114

  18. National Level Assessment of Mangrove Forest Cover in Pakistan

    NASA Astrophysics Data System (ADS)

    Abbas, S.; Qamer, F. M.; Hussain, N.; Saleem, R.; Nitin, K. T.

    2011-09-01

    Mangroves ecosystems consist of inter tidal flora and fauna found in the tropical and subtropical regions of the world. Mangroves forest is a collection of halophytic trees, shrubs, and other plants receiving inputs from regular tidal flushing and from freshwater streams and rivers. A global reduction of 25 % mangroves' area has been observed since 1980 and it is categorized as one of to the most threatened and vulnerable ecosystems of the world. Forest resources in Pakistan are being deteriorating both quantitatively and qualitatively due to anthropogenic activities, climatic v and loose institutional management. According to the FAO (2007), extent of forest cover of Pakistan in 2005 is 1,902,000 ha, which is 2.5% of its total land area. Annual change rate during 2000-2005 was -2.1% which is highest among all the countries in Asia. The Indus delta region contains the world's fifth-largest mangrove forest which provides a range of important ecosystem services, including coastal stabilisation, primary production and provision of nursery habitat for marine fish. Given their ecological importance in coastal settings, mangroves receive special attention in the assessment of conservation efforts and sustainable coastal developments. Coastline of Pakistan is 1050km long shared by the provinces, Sind (350km) and Baluchistan (700 km). The coastline, with typical arid subtropical climate, possesses five significant sites that are blessed with mangroves. In the Sindh province, mangroves are found in the Indus Delta and Sandspit. The Indus Delta is host to the most extensive mangroves areas and extends from Korangi Creek in the West to Sir Creek in the East, whereas Sandspit is a small locality in the West of Karachi city. In the Balochistan province, mangroves are located at three sites, Miani Hor, Kalmat Khor and Jiwani. Contemporary methods of Earth observation sciences are being incorporated as an integral part of environmental assessment related studies in coastal areas

  19. Blue Carbon distribution in mangrove forests of the Americas

    NASA Astrophysics Data System (ADS)

    Simard, M.; Rivera-Monroy, V.; Fatoyinbo, T. E.; Roy Chowdhury, R.

    2013-12-01

    Globally, coastal ecosystems are critical to maintaining human livelihood and biodiversity. These ecosystems including mangroves, salt marshes, and sea grasses provide essential ecosystem services, such as supporting fisheries by providing important spawning grounds, filtering pollutants and contaminants from coastal waters, and protecting coastal development and communities against storms, floods and erosion. Additionally, recent research indicates that these vegetated coastal ecosystems are highly efficient carbon sinks (i.e. 'Blue Carbon') and can potentially play a significant role in ameliorating the effect of increasing global climate change by capturing significant amounts of carbon into sediments and plant biomass. The term blue carbon indicates the carbon stored in coastal vegetated wetlands (i.e., mangroves, intertidal marshes, and seagrass meadows). As a result of rapid global changes in coastal regions, it is crucial that we improve our understanding of the current and future state of the remaining coastal ecosystems and associated ecosystem services and their vulnerability to global climate change. In this study, we present a continental scale study of mangrove distribution and assess patterns of forest structural development associated to latitude and geomorphological setting. We produced a baseline map of mangrove canopy height and biomass for all mangrove forests of the Americas using data from the Shuttle Radar Topography Mission (SRTM) and publicly available land cover maps (Figure 1). The resulting canopy height map was calibrated using ICEsat/Geoscience Laser Altimeter system (GLAS). Biomass was derived from field data and allometry. The maps were validated with field data and results in accuracies that vary spatially around 2 to 3m in height and 20% in biomass. Figure 1: Global distribution of mangrove forests (green) and SRTM elevation data. These data were used to produce large scale maps of mangrove canopy height and biomass.

  20. Monitoring coral reefs, seagrasses and mangroves in Costa Rica (CARICOMP).

    PubMed

    Cortés, Jorge; Fonseca, Ana C; Nivia-Ruiz, Jaime; Nielsen-Muñoz, Vanessa; Samper-Villarreal, Jimena; Salas, Eva; Martínez, Solciré; Zamora-Trejos, Priscilla

    2010-10-01

    The coral reefs, seagrasses and mangroves from the Costa Rican Caribbean coast have been monitored since 1999 using the CARICOMP protocol. Live coral cover at Meager Shoal reef bank (7 to 10 m depth) at the Parque Nacional Cahuita (National Park), increased from 13.3% in 1999, to 28.2% in 2003, but decreased during the next 5 years to around 17.5%. Algal cover increased significantly since 2003 from 36.6% to 61.3% in 2008. The density of Diadema antillarum oscillated between 2 and 7ind/m2, while Echinometra viridis decreased significantly from 20 to 0.6ind/m2. Compared to other CARICOMP sites, live coral cover, fish diversity and density, and sea urchin density were low, and algal cover was intermediate. The seagrass site, also in the Parque Nacional Cahuita, is dominated by Thalassia testudinum and showed an intermediate productivity (2.7 +/- 1.15 g/m2/d) and biomass (822.8 +/- 391.84 g/m2) compared to other CARICOMP sites. Coral reefs and seagrasses at the Parque Nacional Cahuita continue to be impacted by high sediment loads from terrestrial origin. The mangrove forest at Gandoca, within the Refugio Nacional de Vida Silvestre Gandoca-Manzanillo (National Wildlife Refuge), surrounds a lagoon and it is dominated by the red mangrove, Rhizophora mangle. Productivity and flower production peak was in July. Biomass (14 kg/m2) and density (9.0 +/- 0.58 trees/100 m2) in Gandoca were relatively low compared to other CARICOMP sites, while productivity in July in Costa Rica (4 g/m2/d) was intermediate, similar to most CARICOMP sites. This mangrove is expanding and has low human impact thus far. Management actions should be taken to protect and preserve these important coastal ecosystems. PMID:21302409

  1. Woody Debris in the mangrove forests of South Florida

    USGS Publications Warehouse

    Krauss, K.W.; Doyle, T.W.; Twilley, R.R.; Smith, T. J.; Whelan, K.R.T.; Sullivan, J.K.

    2005-01-01

    Woody debris is abundant in hurricane-impacted forests. With a major hurricane affecting South Florida mangroves approximately every 20 yr, carbon storage and nutrient retention may be influenced greatly by woody debris dynamics. In addition, woody debris can influence seedling regeneration in mangrove swamps by trapping propagules and enhancing seedling growth potential. Here, we report on line-intercept woody debris surveys conducted in mangrove wetlands of South Florida 9-10 yr after the passage of Hurricane Andrew. The total volume of woody debris for all sites combined was estimated at 67 m 3/ha and varied from 13 to 181 m3/ha depending upon differences in forest height, proximity to the storm, and maximum estimated wind velocities. Large volumes of woody debris were found in the eyewall region of the hurricane, with a volume of 132 m3/ha and a projected woody debris biomass of approximately 36 t/ha. Approximately half of the woody debris biomass averaged across all sites was associated as small twigs and branches (fine woody debris), since coarse woody debris >7.5 cm felled during Hurricane Andrew was fairly well decomposed. Much of the small debris is likely to be associated with post-hurricane forest dynamics. Hurricanes are responsible for large amounts of damage to mangrove ecosystems, and components of associated downed wood may provide a relative index of disturbance for mangrove forests. Here, we suggest that a fine:coarse woody debris ratio ???0.5 is suggestive of a recent disturbance in mangrove wetlands, although additional research is needed to corroborate such findings.

  2. Distribution and dynamics of mangrove forests of South Asia

    USGS Publications Warehouse

    Giri, Chandra; Long, Jordan; Abbas, Sawaid; Murali, R. Mani; Qamer, Faisal M.; Pengra, Bruce; Thau, David

    2014-01-01

    Our findings revealed that the areal extent of mangrove forests in South Asia is approximately 1,187,476 ha representing ∼7% of the global total. Our results showed that from 2000 to 2012, 92,135 ha of mangroves were deforested and 80,461 ha were reforested with a net loss of 11,673 ha. In all three case studies, mangrove areas have remained the same or increased slightly, however, the turnover was greater than the net change. Both, natural and anthropogenic factors are responsible for the change and turnover. The major causes of forest cover change are similar throughout the region; however, specific factors may be dominant in specific areas. Major causes of deforestation in South Asia include (i) conversion to other land use (e.g. conversion to agriculture, shrimp farms, development, and human settlement), (ii) over-harvesting (e.g. grazing, browsing and lopping, and fishing), (iii) pollution, (iv) decline in freshwater availability, (v) floodings, (vi) reduction of silt deposition, (vii) coastal erosion, and (viii) disturbances from tropical cyclones and tsunamis. Our analysis in the region's diverse socio-economic and environmental conditions highlights complex patterns of mangrove distribution and change. Results from this study provide important insight to the conservation and management of the important and threatened South Asian mangrove ecosystem.

  3. Mangrove forest composition and structure in Las Perlas Archipelago, Pacific Panama.

    PubMed

    McGowan, Tom; Cunningham, Sarah L; Guzmán, Héctor M; Mair, James M; Guevara, José M; Betts, Tanja

    2010-09-01

    Mangrove forest is an important ecosystem that provides many services, but in Panama, as in other countries, they are under threat due to a variety of human activities. Nowadays, large areas of mangroves continue to be lost without been described and lack of management strategies. This study focused on the mangrove structure in the two largest islands, Isla del Rey and Isla San Jose, of Las Perlas Archipelago (LPA), Pacific Panama. Assessment of Landsat satellite imagery revealed loss of mangroves in the LPA of 965ha in the period 1974-1986, and 248ha in the period 1986-2000. The majority of the loss (>77%) from the two study islands was due to timber extraction and agricultural development. In May 2006, permanent plots following the CARICOMP protocol were established at two sites on Isla del Rey (R1 and R2) and one site on Isla San Jose (SJ) where standardized metrics such as species, height and diameter at breast height of adult trees and seedlings were recorded. Forest structure differed at the three sites, although R1 and R2 were most similar. At R1, Laguncularia racemosa was the important species and R2 was dominated by Pelliciera rhizophorae. Examination of the forest structure and classified imagery indicated that these sites are spatially dynamic and appear to be rejuvenating. The forest structure would indicate that the sites have been growth-limited previously by human activities and possibly by other factors. SJ was dominated by Rhizophora mangle and appears to have a mature forest with large adult trees and few seedlings. It does not appear to have shown the same extent of spatial regrowth as the other two sites between 1986 and 2000 and is relatively static. The establishment of permanent plots and monitoring will be useful as part of the management plan, as the LPA shows a variety of mangrove structures and could be subject to further coastal development. PMID:20737843

  4. The importance of mangrove forest in tsunami disaster mitigation.

    PubMed

    Osti, Rabindra; Tanaka, Shigenobu; Tokioka, Toshikazu

    2009-04-01

    Tsunamis and storm surges have killed more than one million people and some three billion people currently live with a high risk of these disasters, which are becoming more frequent and devastating worldwide. Effective mitigation of such disasters is possible via healthy coastal forests, which can reduce the energy of tsunamis. In recent years, these natural barriers have declined due to adverse human and natural activities. In the past 20 years, the world has lost almost 50 per cent of its mangrove forests, making them one of the most endangered landscapes. It is essential to recover them and to use them as a shield against a tsunami and as a resource to secure optimal socio-economic, ecological and environmental benefits. This paper examines the emerging scenario facing mangrove forests, discusses protection from tsunamis, and proposes a way to improve the current situation. We hope that practical tips will help communities and agencies to work collectively to achieve a common goal. PMID:18699857

  5. Impacts of exotic mangrove forests and mangrove deforestation on carbon remineralization and ecosystem functioning in marine sediments

    USGS Publications Warehouse

    Sweetman, A.K.; Middelburg, J.J.; Berle, A.M.; Bernardino, A.F.; Schander, C.; Demopoulos, A.W.J.; Smith, C.R.

    2010-01-01

    To evaluate how mangrove invasion and removal can modify benthic carbon cycling processes and ecosystem functioning, we used stable-isotopically labelled algae as a deliberate tracer to quantify benthic respiration and C-flow through macrofauna and bacteria in sediments collected from (1) an invasive mangrove forest, (2) deforested mangrove sites 2 and 6 years after removal of above-sediment mangrove biomass, and (3) two mangrove-free, control sites in the Hawaiian coastal zone. Sediment oxygen consumption (SOC) rates were significantly greater in the mangrove and mangrove removal site experiments than in controls and were significantly correlated with total benthic (macrofauna and bacteria) biomass and sedimentary mangrove biomass (SMB). Bacteria dominated short-term C-processing of added microalgal-C and benthic biomass in sediments from the invasive mangrove forest habitat. In contrast, macrofauna were the most important agents in the short-term processing of microalgal-C in sediments from the mangrove removal and control sites. Mean faunal abundance and short term C-uptake rates in sediments from both removal sites were significantly higher than in control cores, which collectively suggest that community structure and short-term C-cycling dynamics in habitats where mangroves have been cleared can remain fundamentally different from un-invaded mudflat sediments for at least 6-yrs following above-sediment mangrove removal. In summary, invasion by mangroves can lead to large shifts in benthic ecosystem function, with sediment metabolism, benthic community structure and short-term C-remineralization dynamics being affected for years following invader removal. ?? 2010 Author(s).

  6. Ecosystem-Level Carbon Stocks in Costa Rican Mangrove Forests

    NASA Astrophysics Data System (ADS)

    Cifuentes, M.

    2012-12-01

    Tropical mangroves provide a wide variety of ecosystem services, including atmospheric carbon sequestration. Because of their high rates of carbon accumulation, the large expected size of their total stocks (from 2 to 5 times greater than those of upland tropical forests), and the alarming rates at which they are being converted to other uses (releasing globally from 0.02 to 0.12 Pg C yr-1), mangroves are receiving increasing attention as additional tools to mitigate climate change. However, data on whole ecosystem-level carbon in tropical mangroves is limited. Here I present the first estimate of ecosystem level carbon stocks in mangrove forests of Central America. I established 28, 125 m-long, sampling transects along the 4 main rivers draining the Térraba-Sierpe National Wetland in the southern Pacific coast of Costa Rica. This area represents 39% of all remaining mangroves in the country (48300 ha). A circular nested plot was placed every 25 m along each transect. Carbon stocks of standing trees, regeneration, the herbaceous layer, litter, and downed wood were measured following internationally-developed methods compatible with IPCC "Good Practice Guidelines". In addition, total soil carbon stocks were determined down to 1 m depth. Together, these carbon estimates represent the ecosystem-carbon stocks of these forests. The average aboveground carbon stocks were 72.5 ± 3.2 MgC ha-1 (range: 9 - 241 MgC ha-1), consistent with results elsewhere in the world. Between 74 and 92% of the aboveground carbon is stored in trees ≥ 5cm dbh. I found a significant correlation between basal area of trees ≥ 5cm dbh and total aboveground carbon. Soil carbon stocks to 1 m depth ranged between 141 y 593 MgC ha-1. Ecosystem-level carbon stocks ranged from 391 MgC ha-1 to 438 MgC ha-1, with a slight increase from south to north locations. Soil carbon stocks represent an average 76% of total ecosystem carbon stocks, while trees represent only 20%. These Costa Rican mangroves

  7. Material flux in mangrove forest based on the field observation.

    NASA Astrophysics Data System (ADS)

    Terada, K.; Koibuchi, Y.; Isobe, M.

    2008-12-01

    Mangrove ecosystems play important roles in conservation of seashore lines and spawning and nursery of aquatic creatures. It is important to understand nutrient budgets and links between human activities and their effects on mangrove ecosystems. However, we have less knowledge about mangrove ecosystems than that about many other ecosystems. To quantify total material balances in the estuary centered in mangrove forest, we have measured nutrient cycling and CH4 and CO2 gas fluxes in Fukido mangrove creek, Ishigaki island, Okinawa, Japan. It was conducted over tidal cycles from 2006 to 2008. To understand the difference between weather conditions, we investigated on both of rainy day and fine day. Water budget in the river was controlled by tidal exchange at estuary and the input budget from upriver was not dominant for the total budget even if it"fs rain"DFrom estimation of suspended solids (SS) budgets, SS was flowed in the river from upriver significantly on rainy day (more than 5 times inflow of fine day). The amount of SS accumulation in mangrove forest on rainy day (316 kg/day) was about 10 times amount of fine day. Total nitrogen (T-N) and total phosphorus (T-P) budgets also showed accumulation in mangrove. The outflow of T-P to coastal area on rainy day was 0.046 kgPO4/day and nearly equal to fine day. In contrast, T-N outflow to coastal on rainy day (0.58 kgN/day) was about 100 times of fine day. T-N budget showed different behavior from T-P. Ammonia nitrogen (NH4+-N) was dissolved from mangrove forest (~3.83 kgN/day by the nutrient dissolution experiments) and flowed out to estuary under certain conditions. In addition"Cconcentrations of total organic carbon (TOC) in mangrove creeks increased on fine days (11.2~15.5 mgC/L) and decreased on rainy days(1.8~4.9 mgC/L). It suggested the TOC dissolution to creek water from mangrove carbon-rich sediments and dilution effects by rain. Continuous measurements of gas fluxes showed that the CH4 and CO2 emissions from

  8. Discrimination of mangrove species in Matang Mangrove Forest Reserve, Perak using in-situ measurement of hyperspectral leaf reflectance

    NASA Astrophysics Data System (ADS)

    Chun, Beh Boon; Keat, Sim Chong; Syahreza, Saumi; Jafri, Mohd Zubir Mat; San, Lim Hwee

    2015-04-01

    Studies of mangrove species's reflectance characteristic are important in order to have a deep understanding of mangrove vegetation. In this paper, the significant wavelengths which can be used to separate the six mangrove species at Matang Mangrove Forest Reserve (MMFR), Perak were examined. The investigated mangrove species comprise of Rhizophora apiculata, Acrostichum aurem, Acrostichum speciosum, Acanthus ilicifolius, Ceriops tagal and Sonneratia ovata. In-situ spectral reflectance data of six mangrove species's leaf were obtained using ASD FieldSpec3 spectroradiometer and were statistically tested using SPSS program. First, wavelengths which exhibited significant differences (P value<0.05) among the mean reflectance of six mangrove species were identified using a series of one way ANOVA. Second, the identified wavelengths were further analyzed using canonical stepwise discriminant analysis and 26 significant wavelengths were obtained which can be utilized to distinguish among the six mangrove species. In conclusion, each mangrove species in MMFR have it own unique reflectance properties and these characteristic enable the mangrove species can be discriminated among each other under proper analysis and data extraction.

  9. The mangrove pump: The tidal flushing of animal burrows in a tropical mangrove forest determined from radionuclide budgets

    NASA Astrophysics Data System (ADS)

    Stieglitz, Thomas C.; Clark, Jordan F.; Hancock, Gary J.

    2013-02-01

    Intertidal mangrove forests contribute significantly to biogeochemical solute budgets of tropical and subtropical coastlines. A significant part of the biogeochemical cycling in mangrove ecosystems occurs within the subsurface of the forest floor. This subsurface source and the 'offshore' sink are linked by the tidally-driven movement of water through the mangrove forest floor. The tidal circulation through animal macro-burrows in the Coral Creek mangrove forest (area 3 km2) on Hinchinbrook Island (Australia) is documented by constructing mass balances of isotopes of radium and radon measured in the creek in 1997 and 2005 respectively. Isotope activities in burrows were found to be significantly greater than in the adjacent mangrove creek (e.g. for 222Rn, 680-1750 and 30-170 Bq m-3 in burrows and creek respectively). From isotope mass balances, a daily water circulation flux through burrows of 30.4 ± 4.7 L m-2 of forest floor is calculated. This study quantifies the underlying physical process, i.e. the tidal flushing of burrows, that supports significant and continuous exports of soluble organic and inorganic matter from mangrove forest floors to the coastal ocean. The potential significance of the circulation flux estimate is illustrated by up-scaling of the forest-scale estimates to the mangrove forests in the entire central Great Barrier Reef. This extrapolation indicates that the annual water flux circulated by this tidally-driven 'mangrove pump' is equivalent to as much as 20% (16-22%) of the total annual river discharge along the ca. 400 km long coastline of this region.

  10. Plastic debris retention and exportation by a mangrove forest patch.

    PubMed

    Ivar do Sul, Juliana A; Costa, Monica F; Silva-Cavalcanti, Jacqueline S; Araújo, Maria Christina B

    2014-01-15

    An experiment observed the behavior of selected tagged plastic items deliberately released in different habitats of a tropical mangrove forest in NE Brazil in late rainy (September) and late dry (March) seasons. Significant differences were not reported among seasons. However, marine debris retention varied among habitats, according to characteristics such as hydrodynamic (i.e., flow rates and volume transported) and relative vegetation (Rhizophora mangle) height and density. The highest grounds retained significantly more items when compared to the borders of the river and the tidal creek. Among the used tagged items, PET bottles were more observed and margarine tubs were less observed, being easily transported to adjacent habitats. Plastic bags were the items most retained near the releasing site. The balance between items retained and items lost was positive, demonstrating that mangrove forests tend to retain plastic marine debris for long periods (months-years).

  11. Plastic debris retention and exportation by a mangrove forest patch.

    PubMed

    Ivar do Sul, Juliana A; Costa, Monica F; Silva-Cavalcanti, Jacqueline S; Araújo, Maria Christina B

    2014-01-15

    An experiment observed the behavior of selected tagged plastic items deliberately released in different habitats of a tropical mangrove forest in NE Brazil in late rainy (September) and late dry (March) seasons. Significant differences were not reported among seasons. However, marine debris retention varied among habitats, according to characteristics such as hydrodynamic (i.e., flow rates and volume transported) and relative vegetation (Rhizophora mangle) height and density. The highest grounds retained significantly more items when compared to the borders of the river and the tidal creek. Among the used tagged items, PET bottles were more observed and margarine tubs were less observed, being easily transported to adjacent habitats. Plastic bags were the items most retained near the releasing site. The balance between items retained and items lost was positive, demonstrating that mangrove forests tend to retain plastic marine debris for long periods (months-years). PMID:24321881

  12. Sediment properties and CO2 efflux from intact and cleared temperate mangrove forests

    NASA Astrophysics Data System (ADS)

    Bulmer, R. H.; Lundquist, C. J.; Schwendenmann, L.

    2015-10-01

    Temperate mangrove forests in New Zealand have increased in area over recent decades. Expansion of temperate mangroves in New Zealand is associated with perceived loss of other estuarine habitats, and decreased recreational and amenity values, resulting in clearing of mangrove forests. In the tropics, changes in sediment characteristics and carbon efflux have been reported following mangrove clearance. This is the first study in temperate mangrove (Avicennia marina) forests investigating the impact of clearing on sediment CO2 efflux and associated biotic and abiotic factors. Sediment CO2 efflux rates from intact (168.5 ± 45.8 mmol m-2 d-1) and cleared (133.9 ± 37.2 mmol m-2 d-1) mangrove forests in New Zealand are comparable to rates measured in tropical mangrove forests. We did not find a significant difference in sediment CO2 efflux rates between intact and cleared temperate mangrove forests. Pre-shading the sediment for more than 30 min prior to dark chamber measurements was found to have no significant effect on sediment CO2 efflux. This suggests that the continuation of photosynthetic CO2 uptake by biofilm communities was not occurring after placement of dark chambers. Rather, above-ground mangrove biomass, sediment temperature and chlorophyll a concentration were the main factors explaining the variability in sediment CO2 efflux in intact mangrove forests. The main factors influencing sediment CO2 efflux in cleared mangrove forest sites were sediment organic carbon concentration, nitrogen concentration and sediment grain size. Our results show that greater consideration should be given regarding the rate of carbon released from mangrove forest following clearance and the relative contribution to global carbon emissions.

  13. Monitoring Environmental Impacts on Mangrove Ecosystem in the Indus Delta of Pakistan

    NASA Astrophysics Data System (ADS)

    Siddiqui, Mehrun-Nisa

    Monitoring Environmental Impacts on Mangrove Ecosystem in the Indus Delta of Pakistan The mangrove forests growing in intertidal region along the tropical coastlines form a unique ecosystem with rich floral species and marine resources. In Pakistan, large mangrove forests are found all along the muddy coast of Sindh province at Indus Deltaic region. These mangroves are threatened by a variety of environmental pollution, like: dumping of untreated industrial and urban waste, sewage water; hazardous chemical released during ship breaking, oil spills, mangroves cutting, over fishing, scarcity of fresh water, seawater intrusion and unplanned urban development, etc. Dams and barrages, constructed on the mighty Indus River have reduced the supply of freshwater into the delta and consequently, seawater intruding into the riverine tract. The Tidal Link, constructed in 1995 to drain the agriculture effluents of cultivated areas of Sindh to sea, has also greatly damaged the ecology of the area. This study is based on integrated use of RS & GIS techniques for monitoring environmental impacts on the mangroves ecosystem of Indus Delta, for management and planning of this coastal ecosystem. Temporal satellite remote sensing (SRS) data acquired between 1976 to 2005 have been analysed using image processing and GIS techniques and coastal landuse maps representing coverage of the deltaic region have been prepared, which enabled to monitor dynamic and geomorphological changes occurred in the area. The tidal boundaries derived from temporal SRS data have been integrated to understand the coastal processes and their impact on mangroves ecosystem, and on tidal / intertidal zones. From the analysis, it was observed that the surface salt accumulation and dryness in the deltaic region and waterlogging & salinity in inland areas have been increased over the last 30 years, indicate the intrusion of seawater in groundwater aquifers and reduction in over all biomass in the area. This study

  14. Status and changes of mangrove forest in Mekong Delta: Case study in Tra Vinh, Vietnam

    NASA Astrophysics Data System (ADS)

    Thu, Phan Minh; Populus, Jacques

    2007-01-01

    Because shrimp culture in the Mekong Delta develops rapidly, it has negatively impacted the environment, socio-economics and natural resources. In particular, mangrove forests have been altered by the shrimp culture. The area of mangrove forests in the region has been reduced and this is seen especially in Tra Vinh province. The results obtained from GIS (Geography Information System) and RS (Remote Sensing) show the status of mangrove forests in Tra Vinh province in 1965, 1995 (Northeastern part of Tra Vinh Province) and 2001. In 1965, the area of mangrove forests was 21,221 ha making up 56% of total land-use, while in 2001 it was 12,797 ha making up 37% of total land-use. Also based on GIS analysis, over the 36 years (1965-2001), the total coverage of mangrove forests have decreased by 50% since 1965. However, the speed of mangrove forest destruction in the period from 1965 to 1995 was much less than that in the period from 1995 to 2001. The average annual reduction in mangrove forest coverage in the first period (1965-1995) was 0.2% whereas it was 13.1% in the later period (1995-2001). For the long time, mangrove deforestation has been caused by war, collection of firewood and clearing for agriculture, and recently, shrimp farming has significantly contributed rate of mangrove destruction.

  15. Mapping and monitoring Louisiana's mangroves in the aftermath of the 2010 Gulf of Mexico Oil spill

    USGS Publications Warehouse

    Giri, C.; Long, J.; Tieszen, L.

    2011-01-01

    Information regarding the present condition, historical status, and dynamics of mangrove forests is needed to study the impacts of the Gulf of Mexico oil spill and other stressors affecting mangrove ecosystems. Such information is unavailable for Louisiana at sufficient spatial and thematic detail. We prepared mangrove forest distribution maps of Louisiana (prior to the oil spill) at 1 m and 30 m spatial resolution using aerial photographs and Landsat satellite data, respectively. Image classification was performed using a decision-tree classification approach. We also prepared land-cover change pairs for 1983, 1984, and every 2 y from 1984 to 2010 depicting ecosystem shifts (e.g., expansion, retraction, and disappearance). This new spatiotemporal information could be used to assess short-term and long-term impacts of the oil spill on mangroves. Finally, we propose an operational methodology based on remote sensing (Landsat, Advanced Spaceborne Thermal Emission and Reflection Radiometer [ASTER], hyperspectral, light detection and ranging [LIDAR], aerial photographs, and field inventory data) to monitor the existing and emerging mangrove areas and their disturbance and regrowth patterns. Several parameters such as spatial distribution, ecosystem shifts, species composition, and tree height/biomass could be measured to assess the impact of the oil spill and mangrove recovery and restoration. Future research priorities will be to quantify the impacts and recovery of mangroves considering multiple stressors and perturbations, including oil spill, winter freeze, sea-level rise, land subsidence, and land-use/land-cover change for the entire Gulf Coast. ?? 2011 Coastal Education & Research Foundation.

  16. Are mangroves in the tropical Atlantic ripe for invasion? Exotic mangrove trees in the forests of South Florida

    USGS Publications Warehouse

    Fourqurean, James W.; Smith, Thomas J.; Possley, Jennifer; Collins, Timothy M.; Lee, David; Namoff, Sandra

    2010-01-01

    Two species of mangrove trees of Indo-Pacific origin have naturalized in tropical Atlantic mangrove forests in South Florida after they were planted and nurtured in botanic gardens. Two Bruguiera gymnorrhiza trees that were planted in the intertidal zone in 1940 have given rise to a population of at least 86 trees growing interspersed with native mangrove species Rhizophora mangle, Avicennia germinans and Laguncularia racemosa along 100 m of shoreline; the population is expanding at a rate of 5.6% year-1. Molecular genetic analyses confirm very low genetic diversity, as expected from a population founded by two individuals. The maximumnumber of alleles at any locus was three, and we measured reduced heterozygosity compared to native-range populations. Lumnitzera racemosa was introduced multiple times during the 1960s and 1970s, it has spread rapidly into a forest composed of native R. mangle, A. germinans, Laguncularia racemosa and Conocarpus erectus and now occupies 60,500 m2 of mangrove forest with stem densities of 24,735 ha-1. We estimate the population growth rate of Lumnitzera racemosa to be between 17 and 23% year-1. Populations of both species of naturalized mangroves are dominated by young individuals. Given the long life and water-dispersed nature of propagules of the two exotic species, it is likely that they have spread beyond our survey area. We argue that the species-depauperate nature of tropical Atlantic mangrove forests and close taxonomic relatives in the more species-rich Indo-Pacific region result in the susceptibility of tropical Atlantic mangrove forests to invasion by Indo-Pacific mangrove species.

  17. Species diversity of culturable endophytic fungi from Brazilian mangrove forests.

    PubMed

    de Souza Sebastianes, Fernanda Luiza; Romão-Dumaresq, Aline Silva; Lacava, Paulo Teixeira; Harakava, Ricardo; Azevedo, João Lúcio; de Melo, Itamar Soares; Pizzirani-Kleiner, Aline Aparecida

    2013-08-01

    This study aimed to perform a comparative analysis of the diversity of endophytic fungal communities isolated from the leaves and branches of Rhizophora mangle, Avicennia schaueriana and Laguncularia racemosa trees inhabiting two mangroves in the state of São Paulo, Brazil [Cananeia and Bertioga (oil spill-affected and unaffected)] in the summer and winter. Three hundred and forty-three fungi were identified by sequencing the ITS1-5.8S-ITS2 region of rDNA. Differences were observed in the frequencies of fungi isolated from the leaves and branches of these three different plant species sampled from the Bertioga oil spill-affected and the oil-unaffected mangrove sites in the summer and winter; these differences indicate a potential impact on fungal diversity in the study area due to the oil spill. The molecular identification of the fungi showed that the fungal community associated with these mangroves is composed of at least 34 different genera, the most frequent of which were Diaporthe, Colletotrichum, Fusarium, Trichoderma and Xylaria. The Shannon and the Chao1 indices [H'(95 %) = 4.00, H'(97 %) = 4.22, Chao1(95 %) = 204 and Chao1(97 %) = 603] indicated that the mangrove fungal community possesses a vast diversity and richness of endophytic fungi. The data generated in this study revealed a large reservoir of fungal genetic diversity inhabiting these Brazilian mangrove forests and highlighted substantial differences between the fungal communities associated with distinct plant tissues, plant species, impacted sites and sampling seasons. PMID:23832271

  18. Approximations of stand water use versus evapotranspiration from three mangrove forests in southwest Florida, USA

    USGS Publications Warehouse

    Krauss, Ken W.; Barr, Jordan G.; Engel, Victor C.; Fuentes, Jose D.; Wang, Hongqing

    2014-01-01

    Leaves from mangrove forests are often considered efficient in the use of water during photosynthesis, but less is known about whole-tree and stand-level water use strategies. Are mangrove forests as conservative in water use as experimental studies on seedlings imply? Here, we apply a simple model to estimate stand water use (S), determine the contribution of S to evapotranspiration (ET), and approximate the distribution of S versus ET over annual cycles for three mangrove forests in southwest Florida, USA. The value of S ranged from 350 to 511 mm year−1 for two mangrove forests in Rookery Bay to 872 mm year−1 for a mangrove forest along the Shark River in Everglades National Park. This represents 34–49% of ET for Rookery Bay mangroves, a rather conservative rate ofS, and 63–66% of ET for the Shark River mangroves, a less conservative rate of S. However, variability in estimates of S in mangroves is high enough to require additional study on the spatial changes related to forest structural shifts, different tidal regimes, and variable site-specific salinity concentrations in multiple mangrove forests before a true account of water use conservation strategies can be understood at the landscape scale. Evidence does suggest that large, well-developed mangrove forests have the potential to contribute considerably to the ET balance; however, regionally most mangrove forests are much smaller in stature in Florida and likely contribute less to regional water losses through stand-level transpiration.

  19. Mangrove forest distributions and dynamics (19752005) of the tsunami-affected region of Asia

    USGS Publications Warehouse

    Giri, C.; Zhu, Z.; Tieszen, L.L.; Singh, A.; Gillette, S.; Kelmelis, J.A.

    2008-01-01

    Aim: We aimed to estimate the present extent of tsunami-affected mangrove forests and determine the rates and causes of deforestation from 1975 to 2005. Location: Our study region covers the tsunami-affected coastal areas of Indonesia, Malaysia, Thailand, Burma (Myanmar), Bangladesh, India and Sri Lanka in Asia. Methods: We interpreted time-series Landsat data using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of plus-or-minus half a pixel, an accuracy necessary for change analysis. Each image was normalized for solar irradiance by converting digital number values to the top-of-the atmosphere reflectance. Ground truth data and existing maps and data bases were used to select training samples and also for iterative labelling. We used a post-classification change detection approach. Results: were validated with the help of local experts and/or high-resolution commercial satellite data. Results The region lost 12% of its mangrove forests from 1975 to 2005, to a present extent of c. 1,670,000 ha. Rates and causes of deforestation varied both spatially and temporally. Annual deforestation was highest in Burma (c. 1%) and lowest in Sri Lanka (0.1%). In contrast, mangrove forests in India and Bangladesh remained unchanged or gained a small percentage. Net deforestation peaked at 137,000 ha during 1990-2000, increasing from 97,000 ha during 1975-90, and declining to 14,000 ha during 2000-05. The major causes of deforestation were agricultural expansion (81%), aquaculture (12%) and urban development (2%). Main conclusions: We assessed and monitored mangrove forests in the tsunami-affected region of Asia using the historical archive of Landsat data. We also measured the rates of change and determined possible causes. The results of our study can be used to better understand the role of mangrove forests in saving lives and property from natural disasters such as the Indian Ocean tsunami, and to identify

  20. Bistability of mangrove forests and competition with freshwater plants

    USGS Publications Warehouse

    Jiang, Jiang; Fuller, Douglas O; Teh, Su Yean; Zhai, Lu; Koh, Hock Lye; DeAngelis, Donald L.; Sternberg, L.D.S.L.

    2015-01-01

    Halophytic communities such as mangrove forests and buttonwood hammocks tend to border freshwater plant communities as sharp ecotones. Most studies attribute this purely to underlying physical templates, such as groundwater salinity gradients caused by tidal flux and topography. However, a few recent studies hypothesize that self-reinforcing feedback between vegetation and vadose zone salinity are also involved and create a bistable situation in which either halophytic dominated habitat or freshwater plant communities may dominate as alternative stable states. Here, we revisit the bistability hypothesis and demonstrate the mechanisms that result in bistability. We demonstrate with remote sensing imagery the sharp boundaries between freshwater hardwood hammock communities in southern Florida and halophytic communities such as buttonwood hammocks and mangroves. We further document from the literature how transpiration of mangroves and freshwater plants respond differently to vadose zone salinity, thus altering the salinity through feedback. Using mathematical models, we show how the self-reinforcing feedback, together with physical template, controls the ecotones between halophytic and freshwater communities. Regions of bistability along environmental gradients of salinity have the potential for large-scale vegetation shifts following pulse disturbances such as hurricane tidal surges in Florida, or tsunamis in other regions. The size of the region of bistability can be large for low-lying coastal habitat due to the saline water table, which extends inland due to salinity intrusion. We suggest coupling ecological and hydrologic processes as a framework for future studies.

  1. Mangrove recruitment after forest disturbance is facilitated by herbaceous species in the Caribbean.

    PubMed

    McKee, Karen L; Rooth, Jill E; Feller, Ilka C

    2007-09-01

    Plant communities along tropical coastlines are often affected by natural and human disturbances, but little is known about factors influencing recovery. We focused on mangrove forests, which are among the most threatened ecosystems globally, to examine how facilitation by herbaceous vegetation might improve forest restoration after disturbance. We specifically investigated whether recovery of mangrove forests in harsh environments is accelerated by nurse plants and whether the beneficial effects are species-specific. Quantification of standardized effects allowed comparisons across performance parameters and over time for: (1) net effect of each herbaceous species on mangrove survival and growth, (2) effects of pre- and post-establishment factors associated with each herbaceous species, and (3) need for artificial planting to enhance growth or survival of mangrove seedlings. Mangrove recruitment in a clear-cut forest in Belize was accelerated by the presence of Sesuvium portulacastrum (succulent forb) and Distichlis spicata (grass), two coastal species common throughout the Caribbean region. The net effect of herbaceous vegetation was positive, but the magnitude of effects on mangrove survival and growth differed by species. Because of differences in their vegetative structure and other features, species effects on mangroves also varied by mechanism: (1) trapping of dispersing propagules (both species), (2) structural support of the seedling (Distichlis), and/or (3) promotion of survival (Sesuviumn) or growth (Distichlis) through amelioration of soil conditions (temperature, aeration). Artificial planting had a stronger positive effect on mangrove survival than did edaphic conditions, but planting enhanced mangrove growth more in Sesuvium than in Distichlis patches. Our study indicates that beneficial species might be selected based on features that provide multiple positive effects and that species comparisons may be improved using standardized effects. Our

  2. Mangrove recruitment after forest disturbance is facilitated by herbaceous species in the Caribbean.

    PubMed

    McKee, Karen L; Rooth, Jill E; Feller, Ilka C

    2007-09-01

    Plant communities along tropical coastlines are often affected by natural and human disturbances, but little is known about factors influencing recovery. We focused on mangrove forests, which are among the most threatened ecosystems globally, to examine how facilitation by herbaceous vegetation might improve forest restoration after disturbance. We specifically investigated whether recovery of mangrove forests in harsh environments is accelerated by nurse plants and whether the beneficial effects are species-specific. Quantification of standardized effects allowed comparisons across performance parameters and over time for: (1) net effect of each herbaceous species on mangrove survival and growth, (2) effects of pre- and post-establishment factors associated with each herbaceous species, and (3) need for artificial planting to enhance growth or survival of mangrove seedlings. Mangrove recruitment in a clear-cut forest in Belize was accelerated by the presence of Sesuvium portulacastrum (succulent forb) and Distichlis spicata (grass), two coastal species common throughout the Caribbean region. The net effect of herbaceous vegetation was positive, but the magnitude of effects on mangrove survival and growth differed by species. Because of differences in their vegetative structure and other features, species effects on mangroves also varied by mechanism: (1) trapping of dispersing propagules (both species), (2) structural support of the seedling (Distichlis), and/or (3) promotion of survival (Sesuviumn) or growth (Distichlis) through amelioration of soil conditions (temperature, aeration). Artificial planting had a stronger positive effect on mangrove survival than did edaphic conditions, but planting enhanced mangrove growth more in Sesuvium than in Distichlis patches. Our study indicates that beneficial species might be selected based on features that provide multiple positive effects and that species comparisons may be improved using standardized effects. Our

  3. An Evaluation of Plotless Sampling Using Vegetation Simulations and Field Data from a Mangrove Forest

    PubMed Central

    Hijbeek, Renske; Koedam, Nico; Khan, Md Nabiul Islam; Kairo, James Gitundu; Schoukens, Johan; Dahdouh-Guebas, Farid

    2013-01-01

    In vegetation science and forest management, tree density is often used as a variable. To determine the value of this variable, reliable field methods are necessary. When vegetation is sparse or not easily accessible, the use of sample plots is not feasible in the field. Therefore, plotless methods, like the Point Centred Quarter Method, are often used as an alternative. In this study we investigate the accuracy of different plotless sampling methods. To this end, tree densities of a mangrove forest were determined and compared with estimates provided by several plotless methods. None of these methods proved accurate across all field sites with mean underestimations up to 97% and mean overestimations up to 53% in the field. Applying the methods to different vegetation patterns shows that when random spatial distributions were used the true density was included within the 95% confidence limits of all the plotless methods tested. It was also found that, besides aggregation and regularity, density trends often found in mangroves contribute to the unreliability. This outcome raises questions about the use of plotless sampling in forest monitoring and management, as well as for estimates of density-based carbon sequestration. We give recommendations to minimize errors in vegetation surveys and recommendations for further in-depth research. PMID:23826233

  4. Mangroves among the most carbon-rich forests in the tropics

    NASA Astrophysics Data System (ADS)

    Donato, Daniel C.; Kauffman, J. Boone; Murdiyarso, Daniel; Kurnianto, Sofyan; Stidham, Melanie; Kanninen, Markku

    2011-05-01

    Mangrove forests occur along ocean coastlines throughout the tropics, and support numerous ecosystem services, including fisheries production and nutrient cycling. However, the areal extent of mangrove forests has declined by 30-50% over the past half century as a result of coastal development, aquaculture expansion and over-harvesting. Carbon emissions resulting from mangrove loss are uncertain, owing in part to a lack of broad-scale data on the amount of carbon stored in these ecosystems, particularly below ground. Here, we quantified whole-ecosystem carbon storage by measuring tree and dead wood biomass, soil carbon content, and soil depth in 25 mangrove forests across a broad area of the Indo-Pacific region--spanning 30° of latitude and 73° of longitude--where mangrove area and diversity are greatest. These data indicate that mangroves are among the most carbon-rich forests in the tropics, containing on average 1,023Mg carbon per hectare. Organic-rich soils ranged from 0.5m to more than 3m in depth and accounted for 49-98% of carbon storage in these systems. Combining our data with other published information, we estimate that mangrove deforestation generates emissions of 0.02-0.12Pg carbon per year--as much as around 10% of emissions from deforestation globally, despite accounting for just 0.7% of tropical forest area.

  5. Growth performance of planted mangroves in the Philippines: revisiting forest management strategies.

    PubMed

    Samson, Maricar S; Rollon, Rene N

    2008-06-01

    The effort toward restoring lost mangroves in the Philippines has been commendably immense, specifically during the past two decades. In light of such, it is important to evaluate outcomes and, where appropriate, apply the lessons learned to the current strategies in mangrove forest management. This article synthesizes the results from several research projects assessing the performance of planted mangroves across the country. Overall, there is a widespread tendency to plant mangroves in areas that are not the natural habitat of mangroves, converting mudflats, sandflats, and seagrass meadows into often monospecific Rhizophora mangrove forests. In these nonmangrove areas, the Rhizophora seedlings experienced high mortality. Of the few that survived (often through persistent and redundant replanting), the young Rhizophora individuals planted in these nonmangrove and often low intertidal zones had dismally stunted growth relative to the corresponding growth performance of individuals thriving at the high intertidal position and natural mangrove sites. From this evidence, this article argues that a more rational focus of the restoration effort should be the replanting of mangroves in the brackish-water aquaculture pond environments, the original habitat of mangroves. For such, a number of management options can be explored, the implementation of which will ultimately depend on the political will of local and national governments. PMID:18686501

  6. Cyanobacterial diversity in the phyllosphere of a mangrove forest.

    PubMed

    Rigonato, Janaina; Alvarenga, Danillo Oliveira; Andreote, Fernando Dini; Dias, Armando Cavalcante Franco; Melo, Itamar Soares; Kent, Angela; Fiore, Marli Fátima

    2012-05-01

    The cyanobacterial community colonizing phyllosphere in a well-preserved Brazilian mangrove ecosystem was assessed using cultivation-independent molecular approaches. Leaves of trees that occupy this environment (Rhizophora mangle,Avicennia schaueriana and Laguncularia racemosa) were collected along a transect beginning at the margin of the bay and extending upland. The results demonstrated that the phyllosphere of R. mangle and L. racemosa harbor similar assemblages of cyanobacteria at each point along the transect. A. schaueriana, found only in the coastal portions of the transect, was colonized by assemblages with lower richness than the other trees. However, the results indicated that spatial location was a stronger driver of cyanobacterial community composition than plant species. Distinct cyanobacterial communities were observed at each location along the coast-to-upland transect. Clone library analysis allowed identification of 19 genera of cyanobacteria and demonstrated the presence of several uncultivated taxa. A predominance of sequences affiliated with the orders Nostocales and Oscillatoriales was observed, with a remarkable number of sequences similar to genera Symphyonemopsis/Brasilonema (order Nostocales). The results demonstrated that phyllosphere cyanobacteria in this mangrove forest ecosystem are influenced by environmental conditions as the primary driver at the ecosystem scale, with tree species exerting some effect on community structure at the local scale. PMID:22611551

  7. Cyanobacterial diversity in the phyllosphere of a mangrove forest.

    PubMed

    Rigonato, Janaina; Alvarenga, Danillo Oliveira; Andreote, Fernando Dini; Dias, Armando Cavalcante Franco; Melo, Itamar Soares; Kent, Angela; Fiore, Marli Fátima

    2012-05-01

    The cyanobacterial community colonizing phyllosphere in a well-preserved Brazilian mangrove ecosystem was assessed using cultivation-independent molecular approaches. Leaves of trees that occupy this environment (Rhizophora mangle,Avicennia schaueriana and Laguncularia racemosa) were collected along a transect beginning at the margin of the bay and extending upland. The results demonstrated that the phyllosphere of R. mangle and L. racemosa harbor similar assemblages of cyanobacteria at each point along the transect. A. schaueriana, found only in the coastal portions of the transect, was colonized by assemblages with lower richness than the other trees. However, the results indicated that spatial location was a stronger driver of cyanobacterial community composition than plant species. Distinct cyanobacterial communities were observed at each location along the coast-to-upland transect. Clone library analysis allowed identification of 19 genera of cyanobacteria and demonstrated the presence of several uncultivated taxa. A predominance of sequences affiliated with the orders Nostocales and Oscillatoriales was observed, with a remarkable number of sequences similar to genera Symphyonemopsis/Brasilonema (order Nostocales). The results demonstrated that phyllosphere cyanobacteria in this mangrove forest ecosystem are influenced by environmental conditions as the primary driver at the ecosystem scale, with tree species exerting some effect on community structure at the local scale.

  8. Surface elevation dynamics in a regenerating mangrove forest at Homebush Bay, Australia

    USGS Publications Warehouse

    Rogers, K.; Saintilan, N.; Cahoon, D.

    2005-01-01

    Following the dieback of an interior portion of a mangrove forest at Homebush Bay, Australia, surface elevation tables and feldspar marker horizons were installed in the impacted, intermediate and control forest to measure vertical accretion, elevation change, and shallow subsidence. The objectives of the study were to determine current vertical accretion and elevation change rates as a guide to understanding mangrove dieback, ascertain the factors controlling surface elevation change, and investigate the sustainability of the mangrove forest under estimated sea-level rise conditions. The study demonstrates that the influences on surface dynamics are more complex than soil accretion and soil autocompaction alone. During strong vegetative regrowth in the impacted forest, surface elevation increase exceeded vertical accretion apparently as a result of belowground biomass production. In addition, surface elevation in all forest zones was correlated with total monthly rainfall during a severe El Ni?o event, highlighting the importance of rainfall to groundwater recharge and surface elevation. Surface elevation increase for all zones exceeded the 85-year sea level trend for Sydney Harbour. Since mean sea-level also decreased during the El Ni?o event, the decrease in surface elevation did not translate to an increase in inundation frequency or influence the sustainability of the mangrove forest. These findings indicate that subsurface soil processes such as organic matter accumulation and groundwater flux can significantly influence mangrove surface elevation, and contribute to the long-term sustainability of mangrove systems under a scenario of rising sea levels.

  9. Dynamics of phosphorus and nitrogen through litter fall and decomposition in a tropical mangrove forest.

    PubMed

    Ramos e Silva, Carlos A; Oliveira, Sérgio R; Rêgo, Ronaldo D P; Mozeto, Antonio A

    2007-10-01

    Distribution, dynamics and mass budget of phosphorus and nitrogen in a red mangrove forest were studied in the Potengi mangrove forest in northern Brazil (lat. 5 degrees 42' and 5 degrees 53'S, long. 35 degrees 5' and 35 degrees 25'W). Tidal hydrology, net primary productivity, leaf litter decomposition rate and standing stock of leaf litter in a red mangrove forest were measured. The results showed that the main reservoir for total P and total N was the sediment with 309 kg ha(-1) and 4619 kg ha(-1) (77% and 95% of the total P and N content in the mangrove forest), respectively, for the two elements. Total P and total N in Rhizophora mangle trees accounted for 145+/-14 kg ha(-1) and 216+/-23 kg ha(-1) (23% and 5% of the total P and N in the mangrove forest). The estimated average export rates for P and N through leaf litter are 0.5 kg ha(-1)yr(-1) and 1.6 kg ha(-1)yr(-1) respectively. Our measurements support previous results in concluding that mangrove forests efficiently retain P and N. PMID:17599404

  10. Geoinformatics in mangrove monitoring: damage and recovery after the 2004 Indian Ocean tsunami in Phang Nga, Thailand

    NASA Astrophysics Data System (ADS)

    Kamthonkiat, D.; Rodfai, C.; Saiwanrungkul, A.; Koshimura, S.; Matsuoka, M.

    2011-07-01

    In the aftermath of the 2004 Indian Ocean Tsunami, it has been proven that mangrove ecosystems provide protection against coastal disasters by acting as bioshields. Satellite data have been effectively used to detect, assess, and monitor the changes in mangroves during the pre- and post- tsunami periods. However, not much information regarding mangrove restoration or reforestation is available. Rather than undertaking time-consuming fieldwork, this study proposed using geoinformatic technologies such as Remote Sensing (RS), Geographic Information System (GIS), and Global Positioning System (GPS) to monitor the mangrove recovery. The analysis focused only on the tsunami-impacted mangrove areas along the western coast of the Tai Muang, Takuapa and Khuraburi Districts of Phang Nga Province, southern region of Thailand. The results consisted of 2 parts, first: the supervised classification of main land uses, namely forest, mangrove, agricultural land, built-up area, bare soil, water body, and miscellaneous covers in ASTER images, was conducted using the maximum likelihood method with higher than 75 % for overall accuracy. Once the confusion between classes was improved in post-processing, the accuracy of mangrove class was greater than 85 % for all dates. The results showed that the mangrove area in 2005 was reduced by approximately 5 % (1054.5 ha) from 2003 due to the impact of the 2004 Indian Ocean Tsunami. Although the recovery program (replacing the same species of dead mangrove trees, mainly the Rhizophora apiculata Bl and Rhizophora mucronata Poir, in situ) had started by mid-2005, the areas gradually decreased to approximately 7-8 % in 2006 and 2010 compared with the reference year of 2003. Second, the recovery trend was observed in the Normalized Difference Vegetation Index (NDVI) fluctuation curve and the supporting field survey data. The recovery patterns were summarized into 2 categories: (i) gradually recovery, and (ii) fluctuating recovery. The gradually

  11. Status and distribution of mangrove forests of the world using earth observation satellite data

    USGS Publications Warehouse

    Giri, C.; Ochieng, E.; Tieszen, L.L.; Zhu, Z.; Singh, A.; Loveland, T.; Masek, J.; Duke, N.

    2011-01-01

    Aim Our scientific understanding of the extent and distribution of mangrove forests of the world is inadequate. The available global mangrove databases, compiled using disparate geospatial data sources and national statistics, need to be improved. Here, we mapped the status and distributions of global mangroves using recently available Global Land Survey (GLS) data and the Landsat archive.Methods We interpreted approximately 1000 Landsat scenes using hybrid supervised and unsupervised digital image classification techniques. Each image was normalized for variation in solar angle and earth-sun distance by converting the digital number values to the top-of-the-atmosphere reflectance. Ground truth data and existing maps and databases were used to select training samples and also for iterative labelling. Results were validated using existing GIS data and the published literature to map 'true mangroves'.Results The total area of mangroves in the year 2000 was 137,760 km2 in 118 countries and territories in the tropical and subtropical regions of the world. Approximately 75% of world's mangroves are found in just 15 countries, and only 6.9% are protected under the existing protected areas network (IUCN I-IV). Our study confirms earlier findings that the biogeographic distribution of mangroves is generally confined to the tropical and subtropical regions and the largest percentage of mangroves is found between 5?? N and 5?? S latitude.Main conclusions We report that the remaining area of mangrove forest in the world is less than previously thought. Our estimate is 12.3% smaller than the most recent estimate by the Food and Agriculture Organization (FAO) of the United Nations. We present the most comprehensive, globally consistent and highest resolution (30 m) global mangrove database ever created. We developed and used better mapping techniques and data sources and mapped mangroves with better spatial and thematic details than previous studies. ?? 2010 Blackwell

  12. Winter climate change and coastal wetland foundation species: salt marshes vs. mangrove forests in the southeastern United States.

    PubMed

    Osland, Michael J; Enwright, Nicholas; Day, Richard H; Doyle, Thomas W

    2013-05-01

    We live in an era of unprecedented ecological change in which ecologists and natural resource managers are increasingly challenged to anticipate and prepare for the ecological effects of future global change. In this study, we investigated the potential effect of winter climate change upon salt marsh and mangrove forest foundation species in the southeastern United States. Our research addresses the following three questions: (1) What is the relationship between winter climate and the presence and abundance of mangrove forests relative to salt marshes; (2) How vulnerable are salt marshes to winter climate change-induced mangrove forest range expansion; and (3) What is the potential future distribution and relative abundance of mangrove forests under alternative winter climate change scenarios? We developed simple winter climate-based models to predict mangrove forest distribution and relative abundance using observed winter temperature data (1970-2000) and mangrove forest and salt marsh habitat data. Our results identify winter climate thresholds for salt marsh-mangrove forest interactions and highlight coastal areas in the southeastern United States (e.g., Texas, Louisiana, and parts of Florida) where relatively small changes in the intensity and frequency of extreme winter events could cause relatively dramatic landscape-scale ecosystem structural and functional change in the form of poleward mangrove forest migration and salt marsh displacement. The ecological implications of these marsh-to-mangrove forest conversions are poorly understood, but would likely include changes for associated fish and wildlife populations and for the supply of some ecosystem goods and services.

  13. Winter climate change and coastal wetland foundation species: salt marshes vs. mangrove forests in the southeastern United States

    USGS Publications Warehouse

    Osland, Michael J.; Day, Richard H.; Doyle, Thomas W.; Enwright, Nicholas

    2013-01-01

    We live in an era of unprecedented ecological change in which ecologists and natural resource managers are increasingly challenged to anticipate and prepare for the ecological effects of future global change. In this study, we investigated the potential effect of winter climate change upon salt marsh and mangrove forest foundation species in the southeastern United States. Our research addresses the following three questions: (1) What is the relationship between winter climate and the presence and abundance of mangrove forests relative to salt marshes; (2) How vulnerable are salt marshes to winter climate change-induced mangrove forest range expansion; and (3) What is the potential future distribution and relative abundance of mangrove forests under alternative winter climate change scenarios? We developed simple winter climate-based models to predict mangrove forest distribution and relative abundance using observed winter temperature data (1970–2000) and mangrove forest and salt marsh habitat data. Our results identify winter climate thresholds for salt marsh–mangrove forest interactions and highlight coastal areas in the southeastern United States (e.g., Texas, Louisiana, and parts of Florida) where relatively small changes in the intensity and frequency of extreme winter events could cause relatively dramatic landscape-scale ecosystem structural and functional change in the form of poleward mangrove forest migration and salt marsh displacement. The ecological implications of these marsh-to-mangrove forest conversions are poorly understood, but would likely include changes for associated fish and wildlife populations and for the supply of some ecosystem goods and services.

  14. Winter climate change and coastal wetland foundation species: salt marshes vs. mangrove forests in the southeastern United States.

    PubMed

    Osland, Michael J; Enwright, Nicholas; Day, Richard H; Doyle, Thomas W

    2013-05-01

    We live in an era of unprecedented ecological change in which ecologists and natural resource managers are increasingly challenged to anticipate and prepare for the ecological effects of future global change. In this study, we investigated the potential effect of winter climate change upon salt marsh and mangrove forest foundation species in the southeastern United States. Our research addresses the following three questions: (1) What is the relationship between winter climate and the presence and abundance of mangrove forests relative to salt marshes; (2) How vulnerable are salt marshes to winter climate change-induced mangrove forest range expansion; and (3) What is the potential future distribution and relative abundance of mangrove forests under alternative winter climate change scenarios? We developed simple winter climate-based models to predict mangrove forest distribution and relative abundance using observed winter temperature data (1970-2000) and mangrove forest and salt marsh habitat data. Our results identify winter climate thresholds for salt marsh-mangrove forest interactions and highlight coastal areas in the southeastern United States (e.g., Texas, Louisiana, and parts of Florida) where relatively small changes in the intensity and frequency of extreme winter events could cause relatively dramatic landscape-scale ecosystem structural and functional change in the form of poleward mangrove forest migration and salt marsh displacement. The ecological implications of these marsh-to-mangrove forest conversions are poorly understood, but would likely include changes for associated fish and wildlife populations and for the supply of some ecosystem goods and services. PMID:23504931

  15. RS Application for conducting change detection within the Sundarban Mangrove Forest, Bangladesh to meet REDD+ initiatives

    NASA Astrophysics Data System (ADS)

    Biswas, T.; Maus, P.; Megown, K.

    2011-12-01

    The U.S. Forest Service (USFS) provided technical support to the Resource Information Management System (RIMS) unit of the Forest Department (FD) of Bangladesh in developing a method to monitor changes within the Sundarbans Reserve Forest using remote sensing and GIS technology to meet the Reducing Emissions from Deforestation and Degradation (REDD+) initiatives within Bangladesh. It included comparing the simple image differencing method with the Z-score outlier change detection method to examine changes within the mangroves of Bangladesh. Landsat data from three time periods (1989, 1999, 2009) were used to quantify change within four canopy cover classes (High, Medium, Low, and Very Low) within Sundarbans. The Z-score change analysis and image differencing was done for all the 6 reflective bands obtained from Landsat and two spectral indices NDVI and NDMI, derived from these bands for each year. Our results indicated very subtle changes in the mangrove forest within the past twenty years and the Z-score analysis was found to be more useful in capturing these subtle changes than the simple image difference method. Percent change in Z-score of NDVI provided the most meaningful index of vegetation change. It was used to summarize change for the entire study area by pixel, by canopy cover classes and the management compartment during this analysis. Our analysis showed less than 5% overall change in area within the mangroves for the entire study period. Percent change in forest canopy cover reduced from 4% in 1989-99 to 2% by 1999-2009 indicating an increase in forest canopy cover. Percent change in NDVI Z-score of each pixel was used to compute the overall percent change in z-score within the entire study area, mean percent change within each canopy cover class and management compartments from 1989 to 1999 and from 1999 to 2009. The above analysis provided insight to the spatial distribution of percent change in NDVI between the study periods and helped in

  16. Mangrove and peat swamp forests: refuge habitats for primates and felids.

    PubMed

    Nowak, Katarzyna

    2012-01-01

    Swamp forests may be important refuges for primates and felids where these taxa are threatened with habitat loss. Mangrove and peat swamp forests, impenetrable, wet habitats, inaccessible and uninhabitable for humans, may, in some regions, be the most significant remaining habitats for threatened species. They are nevertheless neglected in field studies compared to relatively species-rich, terrestrial tropical forests probably, in part, because of the difficulties associated with surveying them. As a result, maps of mammal distributions may overlook swamp forests although camera-trapping is gradually rectifying this gap. I have compiled and mapped records of over 60 primate and 20 felid taxa reported to use mangrove and peat swamp forests in Africa and Asia at 47 sites, of which 21 are Afrotropical mangrove, 25 are Indo-Malayan mangrove or peat swamp forest, and 1 is an outlying mangrove site in Japan. Eleven of these are designated Ramsar Sites. I highlight key sites of conservation priority on the basis of primate and felid species richness and composite 'threat scores'. Petit Loango in Gabon and Gunung Palung National Park in Indonesia emerged as top priority sites in Africa and Asia, respectively. Further research on the role of swamp forests in the ecology and persistence of threatened mammals is needed.

  17. Mangrove and peat swamp forests: refuge habitats for primates and felids.

    PubMed

    Nowak, Katarzyna

    2012-01-01

    Swamp forests may be important refuges for primates and felids where these taxa are threatened with habitat loss. Mangrove and peat swamp forests, impenetrable, wet habitats, inaccessible and uninhabitable for humans, may, in some regions, be the most significant remaining habitats for threatened species. They are nevertheless neglected in field studies compared to relatively species-rich, terrestrial tropical forests probably, in part, because of the difficulties associated with surveying them. As a result, maps of mammal distributions may overlook swamp forests although camera-trapping is gradually rectifying this gap. I have compiled and mapped records of over 60 primate and 20 felid taxa reported to use mangrove and peat swamp forests in Africa and Asia at 47 sites, of which 21 are Afrotropical mangrove, 25 are Indo-Malayan mangrove or peat swamp forest, and 1 is an outlying mangrove site in Japan. Eleven of these are designated Ramsar Sites. I highlight key sites of conservation priority on the basis of primate and felid species richness and composite 'threat scores'. Petit Loango in Gabon and Gunung Palung National Park in Indonesia emerged as top priority sites in Africa and Asia, respectively. Further research on the role of swamp forests in the ecology and persistence of threatened mammals is needed. PMID:23363595

  18. Life stage influences the resistance and resilience of black mangrove forests to winter climate extremes

    USGS Publications Warehouse

    Osland, Michael J.; Day, Richard H.; From, Andrew S.; McCoy, Megan L.; McLeod, Jennie L.; Kelleway, Jeffrey

    2015-01-01

    In subtropical coastal wetlands on multiple continents, climate change-induced reductions in the frequency and intensity of freezing temperatures are expected to lead to the expansion of woody plants (i.e., mangrove forests) at the expense of tidal grasslands (i.e., salt marshes). Since some ecosystem goods and services would be affected by mangrove range expansion, there is a need to better understand mangrove sensitivity to freezing temperatures as well as the implications of changing winter climate extremes for mangrove-salt marsh interactions. In this study, we investigated the following questions: (1) how does plant life stage (i.e., ontogeny) influence the resistance and resilience of black mangrove (Avicennia germinans) forests to freezing temperatures; and (2) how might differential life stage responses to freeze events affect the rate of mangrove expansion and salt marsh displacement due to climate change? To address these questions, we quantified freeze damage and recovery for different life stages (seedling, short tree, and tall tree) following extreme winter air temperature events that occurred near the northern range limit of A. germinans in North America. We found that life stage affects black mangrove forest resistance and resilience to winter climate extremes in a nonlinear fashion. Resistance to winter climate extremes was high for tall A. germinans trees and seedlings, but lowest for short trees. Resilience was highest for tall A. germinans trees. These results suggest the presence of positive feedbacks and indicate that climate-change induced decreases in the frequency and intensity of extreme minimum air temperatures could lead to a nonlinear increase in mangrove forest resistance and resilience. This feedback could accelerate future mangrove expansion and salt marsh loss at rates beyond what would be predicted from climate change alone. In general terms, our study highlights the importance of accounting for differential life stage responses and

  19. Tsunami inundation and sediment transport in vicinity of coastal mangrove forest

    USGS Publications Warehouse

    Gelfenbaum, G.; Vatvani, D.; Jaffe, B.; Dekker, F.

    2007-01-01

    Field measurements from Sumatra of tsunami wave height, erosion and deposition form a comprehensive data set that is tested against the Delft3D tsunami inundation and sediment transport model. Relative agreement between measured and modeled maximum water levels and sediment erosion and accumulation provides confidence that the model is reasonably characterizing the important processes of tsunami inundation. Adding a component to account for vegetation, the model is used to explore the effects of fringing mangrove forests on tsunami inundation and sedimentation. In model experiments, mangrove forests modify the water levels and flow speeds reached during tsunami inundation. Simulations with a mangrove forest result in sedimentation in the forest and not erosion, as occurs in the base case with no forest. This difference in sedimentation is important because the change in profile shape increases wave energy reflection off the beach and decreases wave energy penetration onto land.

  20. Mapping and Change Analysis in Mangrove Forest by Using Landsat Imagery

    NASA Astrophysics Data System (ADS)

    Dan, T. T.; Chen, C. F.; Chiang, S. H.; Ogawa, S.

    2016-06-01

    Mangrove is located in the tropical and subtropical regions and brings good services for native people. Mangrove in the world has been lost with a rapid rate. Therefore, monitoring a spatiotemporal distribution of mangrove is thus critical for natural resource management. This research objectives were: (i) to map the current extent of mangrove in the West and Central Africa and in the Sundarbans delta, and (ii) to identify change of mangrove using Landsat data. The data were processed through four main steps: (1) data pre-processing including atmospheric correction and image normalization, (2) image classification using supervised classification approach, (3) accuracy assessment for the classification results, and (4) change detection analysis. Validation was made by comparing the classification results with the ground reference data, which yielded satisfactory agreement with overall accuracy 84.1% and Kappa coefficient of 0.74 in the West and Central Africa and 83.0% and 0.73 in the Sundarbans, respectively. The result shows that mangrove areas have changed significantly. In the West and Central Africa, mangrove loss from 1988 to 2014 was approximately 16.9%, and only 2.5% was recovered or newly planted at the same time, while the overall change of mangrove in the Sundarbans increased approximately by 900 km2 of total mangrove area. Mangrove declined due to deforestation, natural catastrophes deforestation and mangrove rehabilitation programs. The overall efforts in this study demonstrated the effectiveness of the proposed method used for investigating spatiotemporal changes of mangrove and the results could provide planners with invaluable quantitative information for sustainable management of mangrove ecosystems in these regions.

  1. Distribution, Fraction, and Ecological Assessment of Heavy Metals in Sediment-Plant System in Mangrove Forest, South China Sea.

    PubMed

    Li, Ruili; Chai, Minwei; Qiu, Guo Yu

    2016-01-01

    Overlying water, sediment, rhizosphere sediment and mangrove seedlings in the Futian mangrove forest were analyzed for heavy metals. The results showed that mangrove plant acidified sediment and increased organic matter contents. Except for chromium (Cr), nickel (Ni) and copper (Cu) in Aegiceras corniculatum sediment, heavy metals in all sediments were higher than in overlying water, rhizosphere sediment and mangrove root. Heavy metals in Avicennia marina sediments were higher than other sediments. The lower heavy metal biological concentration factors (BCFs) and translocation factors (TFs) indicated that mangrove plant adopted exclusion strategy. The geo-accumulation index, potential ecological risk index and risk assessment code (RAC) demonstrated that heavy metals have posed a considerable ecological risk, especially for cadmium (Cd). Heavy metals (Cr, Ni, Cu and Cd) mainly existed in the reducible fractions. These findings provide actual heavy metal accumulations in sediment-plant ecosystems in mangrove forest, being important in designing the long-term management and conservation policies for managers of mangrove forest.

  2. Community perceptions of state forest ownership and management: a case study of the Sundarbans Mangrove Forest in Bangladesh.

    PubMed

    Roy, Anjan Kumer Dev; Alam, Khorshed; Gow, Jeff

    2013-03-15

    The Sundarbans Mangrove Forest (SMF) is the world's largest mangrove forest and it provides livelihoods to 3.5 million forest-dependent people in coastal Bangladesh. The first study aim was to analyse the efficacy of the state property regime in managing the forest through a close examination of the relationship between property rights and mangrove conservation practices. The second study aim was to explore forest-dependent communities' (FDCs) perceptions about their participation in management and conservation practices. The Schlager and Ostrom theoretical framework was adopted to examine the role of potential ownership variations in a common property resource regime. A survey of 412 FDC households was undertaken. Current management by the Bangladesh Forest Department (BFD) does not result in implementation of mandated mangrove conservation practices. It was found that allocation of property rights to FDCs would be expected to increase conservation practices. 92% of respondents expressed the view that the evidenced rapid degradation over the past 30 years was due primarily to corruption in the BFD. About half of FDCs (46%) surveyed are willing to participate in mangrove conservation through involvement in management as proprietors. Consistent with Schlager and Ostrom's theory, the results indicate the necessity for de facto and de jure ownership and management change from a state to common property regime to ensure FDCs' participation in conservation practices. PMID:23376299

  3. Community perceptions of state forest ownership and management: a case study of the Sundarbans Mangrove Forest in Bangladesh.

    PubMed

    Roy, Anjan Kumer Dev; Alam, Khorshed; Gow, Jeff

    2013-03-15

    The Sundarbans Mangrove Forest (SMF) is the world's largest mangrove forest and it provides livelihoods to 3.5 million forest-dependent people in coastal Bangladesh. The first study aim was to analyse the efficacy of the state property regime in managing the forest through a close examination of the relationship between property rights and mangrove conservation practices. The second study aim was to explore forest-dependent communities' (FDCs) perceptions about their participation in management and conservation practices. The Schlager and Ostrom theoretical framework was adopted to examine the role of potential ownership variations in a common property resource regime. A survey of 412 FDC households was undertaken. Current management by the Bangladesh Forest Department (BFD) does not result in implementation of mandated mangrove conservation practices. It was found that allocation of property rights to FDCs would be expected to increase conservation practices. 92% of respondents expressed the view that the evidenced rapid degradation over the past 30 years was due primarily to corruption in the BFD. About half of FDCs (46%) surveyed are willing to participate in mangrove conservation through involvement in management as proprietors. Consistent with Schlager and Ostrom's theory, the results indicate the necessity for de facto and de jure ownership and management change from a state to common property regime to ensure FDCs' participation in conservation practices.

  4. Mangrove fish: a comparison of community structure between forested and cleared habitats

    NASA Astrophysics Data System (ADS)

    Huxham, M.; Kimani, E.; Augley, J.

    2004-08-01

    The fish communities of mangrove and cleared sites were investigated in Gazi Bay, Kenya. Five forested sites were compared with paired sites that had been cleared of mangroves by human activity. Forested sites included plantations and natural stands of Sonneratia alba and natural Rhizophora mucronata stands. Two methods of stake netting were used to take quantitative samples; method one used a single 100-m-long, 18-mm mesh net, method two used paired 24-m-long, 1-mm mesh nets—samples were taken during seven different months in 2002. Mean abundances of fish found in mangrove and cleared sites, respectively, were 0.004 m -2 and 0.014 m -2 (method 1) and 0.21 m -2 and 0.25 m -2 (method 2). Thirty species were sampled, 12 of which were found exclusively in mangrove habitats and 10 of which were limited to cleared sites. The most abundant species in mangrove plots was Atherina afra (although it was only found in two, large catches); the most abundant in cleared plots was Gerres oyena (found frequently). Mean abundance (using data pooled for all sites) was significantly higher in cleared, compared with forested, sites, and multivariate analysis showed significantly different community structures in the two habitat types. There was large variation in catch rates between dates and sites, with one forested site recording no catches at all. These results do not support the predator refuge hypothesis (which predicts higher abundance of juvenile fish inside mangroves). The low abundance of fish recorded in the mangrove sites may have been due to site-specific factors determining fish abundance within mangrove forests, to the sampling techniques used or to relatively high turbidities at these sites.

  5. The vulnerability of Indo-Pacific mangrove forests to sea-level rise.

    PubMed

    Lovelock, Catherine E; Cahoon, Donald R; Friess, Daniel A; Guntenspergen, Glenn R; Krauss, Ken W; Reef, Ruth; Rogers, Kerrylee; Saunders, Megan L; Sidik, Frida; Swales, Andrew; Saintilan, Neil; Thuyen, Le Xuan; Triet, Tran

    2015-10-22

    Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world's mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070. PMID:26466567

  6. The vulnerability of Indo-Pacific mangrove forests to sea-level rise

    USGS Publications Warehouse

    Lovelock, Catherine E.; Cahoon, Donald R.; Friess, Daniel A.; Guntenspergen, Glenn R.; Krauss, Ken W.; Reef, Ruth; Rogers, Kerrylee; Saunders, Megan L.; Sidik, Frida; Swales, Andrew; Saintilan, Neil; Thuyen, Le Xuan; Triet, Tran

    2015-01-01

    Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves1, 2. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth3. The Indo-Pacific region holds most of the world’s mangrove forests4, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers5. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise6, 7. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments8, 9, 10. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.

  7. Organic carbon burial in a mangrove forest, margin and intertidal mud flat

    NASA Astrophysics Data System (ADS)

    Sanders, Christian J.; Smoak, Joseph M.; Naidu, A. Sathy; Sanders, Luciana M.; Patchineelam, Sambasiva R.

    2010-12-01

    The flux of total organic carbon (TOC) to depositional facies (intertidal mud flat, margin and forest) was quantified for a tropical mangrove forest in Brazil. Results indicate that these mangrove margins and intertidal mudflats are sites of large TOC accumulation, almost four times greater than the global averages for mangrove forests. The TOC burial rates were determined from organic carbon content in sediment cores which were dated using 210Pb. Burial rates were calculated to be 1129, 949, and 353 (g m -2 yr -1), for the mud flat, margin and forest, respectively. Sediment accumulation rates (SAR) were estimated to be 7.3, 5.0 and 2.8 mm yr -1. Sediment characterization (δ 13C, δ 15N, TOC/TN and mud fraction) indicated a representative mangrove system with a record of consistent organic matter flux of up to 100 years. Because of substantial burial of organic carbon in mangrove ecosystems, their role in the global carbon budget must be considered. More importantly, as climate change influences temperature and sea level, mangrove ecosystems will respond to specific climatic conditions.

  8. The vulnerability of Indo-Pacific mangrove forests to sea-level rise.

    PubMed

    Lovelock, Catherine E; Cahoon, Donald R; Friess, Daniel A; Guntenspergen, Glenn R; Krauss, Ken W; Reef, Ruth; Rogers, Kerrylee; Saunders, Megan L; Sidik, Frida; Swales, Andrew; Saintilan, Neil; Thuyen, Le Xuan; Triet, Tran

    2015-10-22

    Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world's mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.

  9. The vulnerability of Indo-Pacific mangrove forests to sea-level rise

    NASA Astrophysics Data System (ADS)

    Lovelock, Catherine E.; Cahoon, Donald R.; Friess, Daniel A.; Guntenspergen, Glenn R.; Krauss, Ken W.; Reef, Ruth; Rogers, Kerrylee; Saunders, Megan L.; Sidik, Frida; Swales, Andrew; Saintilan, Neil; Thuyen, Le Xuan; Triet, Tran

    2015-10-01

    Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world's mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.

  10. Variation in mangrove forest structure and sediment characteristics in Bocas del Toro, Panama

    USGS Publications Warehouse

    Lovelock, C.E.; Feller, Ilka C.; McKee, K.L.; Thompson, R.

    2005-01-01

    Mangrove forest structure and sediment characteristics were examined in the extensive mangroves of Bocas del Toro, Republic of Panama. Forest structure was characterized to determine if spatial vegetation patterns were repeated over the Bocas del Toro landscape. Using a series of permanent plots and transects we found that the forests of Bocas del Toro were dominated by Rhizophora mangle with very few individuals of Avicennia germinans and Laguncularia racemosa. Despite this low species diversity, there was large variation in forest structure and in edaphic conditions (salinity, concentration of available phosphorus, Eh and sulphide concentration). Aboveground biomass varied 20-fold, from 6.8 Mg ha-1 in dwarf forests to 194.3 Mg ha-1 in the forests fringing the land. But variation in forest structure was predictable across the intertidal zone. There was a strong tree height gradient from seaward fringe (mean tree height 3.9 m), decreasing in stature in the interior dwarf forests (mean tree height 0.7 m), and increasing in stature in forests adjacent to the terrestrial forest (mean tree height 4.1 m). The predictable variation in forest structure emerges due to the complex interactions among edaphic and plant factors. Identifying predictable patterns in forest structure will aid in scaling up the ecosystem services provided by mangrove forests in coastal landscapes. Copyright 2005 College of Arts and Sciences.

  11. Bottom sediments affect Sonneratia mangrove forests in the prograding Mekong delta, Vietnam

    NASA Astrophysics Data System (ADS)

    Nardin, William; Woodcock, Curtis E.; Fagherazzi, Sergio

    2016-08-01

    Mangrove forests exert a strong influence on tropical deltas by trapping sediments discharged by rivers and by stabilizing the substrate with roots. Understanding the dynamics of sediments and morphology in and around mangrove forests is critical in order to assess the resilience of coastlines in a period of accelerated sea level rise. In this research, sediment samples, mangrove forest characteristics, and remote sensing data are used to investigate the relationship between mangroves and sediment substrate in the Mekong Delta, Vietnam. Our data show a significant correlation between percent of sand in bottom sediments and density of Sonneratia caseolaris forest. We ascribe this result to higher sediment disturbance in muddy areas that prevents seedling establishment. This correlation potentially allows the determination of substrate characteristics from vegetation attributes detected by remote sensing, despite the impenetrability of the forest canopy. The results presented herein suggest that a supply of sand from the river and hydrodynamic processes moving the sand ashore control the density of the Sonneratia mangrove forests at this location, promoting tidal flat colonization and canopy expansion.

  12. Status and distribution of mangrove forests of the world using earth observation satellite data

    USGS Publications Warehouse

    Giri, Chandra; Ochieng, E.; Tieszen, Larry L.; Zhu, Zhi-Liang; Singh, Ashbindu; Loveland, Thomas R.; Masek, Jeffery G.; Duke, Norm

    2011-01-01

    Aim  Our scientific understanding of the extent and distribution of mangrove forests of the world is inadequate. The available global mangrove databases, compiled using disparate geospatial data sources and national statistics, need to be improved. Here, we mapped the status and distributions of global mangroves using recently available Global Land Survey (GLS) data and the Landsat archive. Methods  We interpreted approximately 1000 Landsat scenes using hybrid supervised and unsupervised digital image classification techniques. Each image was normalized for variation in solar angle and earth–sun distance by converting the digital number values to the top-of-the-atmosphere reflectance. Ground truth data and existing maps and databases were used to select training samples and also for iterative labelling. Results were validated using existing GIS data and the published literature to map ‘true mangroves’. Results  The total area of mangroves in the year 2000 was 137,760 km2 in 118 countries and territories in the tropical and subtropical regions of the world. Approximately 75% of world's mangroves are found in just 15 countries, and only 6.9% are protected under the existing protected areas network (IUCN I-IV). Our study confirms earlier findings that the biogeographic distribution of mangroves is generally confined to the tropical and subtropical regions and the largest percentage of mangroves is found between 5° N and 5° S latitude. Main conclusions  We report that the remaining area of mangrove forest in the world is less than previously thought. Our estimate is 12.3% smaller than the most recent estimate by the Food and Agriculture Organization (FAO) of the United Nations. We present the most comprehensive, globally consistent and highest resolution (30 m) global mangrove database ever created. We developed and used better mapping techniques and data sources and mapped mangroves with better spatial and thematic details than previous studies.

  13. Sensitivity of the sediment trapping capacity of an estuarine mangrove forest

    NASA Astrophysics Data System (ADS)

    Willemsen, P. W. J. M.; Horstman, E. M.; Borsje, B. W.; Friess, D. A.; Dohmen-Janssen, C. M.

    2016-11-01

    Intertidal mangrove forests exist in a dynamic coastal environment that is increasingly impacted by human interference, leading to habitat fragmentation, reduced habitat quality and changing hydrodynamic and geomorphological conditions. Biophysical feedback mechanisms are essential to maintain mangrove ecosystems under such changing conditions, for example by facilitating sediment deposition during periods of tidal flooding to allow for long-term coastal accretion. However, human interferences affect these biophysical interactions. This study investigated the consequences of two widespread anthropogenic intervention scenarios on biophysical interactions in mangroves: sediment starvation (reduced sediment supply) and coastal squeeze (limited landward accommodation space). Field observations of hydrodynamics and sediment dynamics were conducted in Mandai mangrove fringing the sheltered northern shore of Singapore. A process-based numerical model (Delft3D) of this field site was set-up, providing accurate approximations of the observed flow velocities and deposition rates. This model was used for a scenario analysis of the initial response of the sediment trapping capacity in the mangrove system to instantaneous changes related to anthropogenic interventions. This analysis showed increased deposition rates in major parts of the mangrove when sediment supplies increased (up to three times more deposition after 1 tide) or when the landward accommodation space of the mangrove was extended (+ 17% deposition). A comparison of the outcomes of these scenarios with the current state of the mangrove underlined a lack of short-term sediment trapping capacity, affecting the (longer-term) adaptive capacity of the system. Thus, at present Mandai mangrove is potentially affected by reduced sediment supply and limited landward accommodation space. Importantly, actions to reduce this anthropogenic influence could enhance mangroves' sediment trapping capacity, facilitating increased

  14. The potential of Indonesian mangrove forests for global climate change mitigation

    NASA Astrophysics Data System (ADS)

    Murdiyarso, Daniel; Purbopuspito, Joko; Kauffman, J. Boone; Warren, Matthew W.; Sasmito, Sigit D.; Donato, Daniel C.; Manuri, Solichin; Krisnawati, Haruni; Taberima, Sartji; Kurnianto, Sofyan

    2015-12-01

    Mangroves provide a wide range of ecosystem services, including nutrient cycling, soil formation, wood production, fish spawning grounds, ecotourism and carbon (C) storage. High rates of tree and plant growth, coupled with anaerobic, water-logged soils that slow decomposition, result in large long-term C storage. Given their global significance as large sinks of C, preventing mangrove loss would be an effective climate change adaptation and mitigation strategy. It has been reported that C stocks in the Indo-Pacific region contain on average 1,023 MgC ha-1 (ref. ). Here, we estimate that Indonesian mangrove C stocks are 1,083 +/- 378 MgC ha-1. Scaled up to the country-level mangrove extent of 2.9 Mha (ref. ), Indonesia’s mangroves contained on average 3.14 PgC. In three decades Indonesia has lost 40% of its mangroves, mainly as a result of aquaculture development. This has resulted in annual emissions of 0.07-0.21 Pg CO2e. Annual mangrove deforestation in Indonesia is only 6% of its total forest loss; however, if this were halted, total emissions would be reduced by an amount equal to 10-31% of estimated annual emissions from land-use sectors at present. Conservation of carbon-rich mangroves in the Indonesian archipelago should be a high-priority component of strategies to mitigate climate change.

  15. Faunal impact on vegetation structure and ecosystem function in mangrove forests: A review

    USGS Publications Warehouse

    Cannicci, Stefano; Burrows, Damien; Fratini, Sara; Smith, Thomas J.; Offenberg, Joachim; Dahdouh-Guebas, Farid

    2008-01-01

    The last 20 years witnessed a real paradigm shift concerning the impact of biotic factors on ecosystem functions as well as on vegetation structure of mangrove forests. Before this small scientific revolution took place, structural aspects of mangrove forests were viewed to be the result of abiotic processes acting from the bottom-up, while, at ecosystem level, the outwelling hypothesis stated that mangroves primary production was removed via tidal action and carried to adjacent nearshore ecosystems where it fuelled detrital based food-webs. The sesarmid crabs were the first macrofaunal taxon to be considered a main actor in mangrove structuring processes, thanks to a number of studies carried out in the Indo-Pacific forests in the late 1970s and early 1980s. Following these classical papers, a number of studies on Sesarmidae feeding and burrowing ecology were carried out, which leave no doubts about the great importance of these herbivorous crabs in structuring and functioning Old world ecosystems. Although Sesarmidae are still considered very important in shaping mangrove structure and functioning, recent literature emphasizes the significance of other invertebrates. The Ocypodidae have now been shown to have the same role as Sesarmidae in terms of retention of forest products and organic matter processing in New world mangroves. In both New and Old world mangroves, crabs process large amounts of algal primary production, contribute consistently to retention of mangrove production and as ecosystem engineers, change particle size distribution and enhance soil aeration. Our understanding of the strong impact of gastropods, by means of high intake rates of mangrove products and differential consumption of propagules, has changed only recently. The role of insects must also be stressed. It is now clear that older techniques used to assess herbivory rates by insects strongly underestimate their impact, both in case of leaf eating and wood boring species and that

  16. Modeling light use efficiency in a subtropical mangrove forest equipped with CO2 eddy covariance

    USGS Publications Warehouse

    Barr, J.G.; Engel, V.; Fuentes, J.D.; Fuller, D.O.; Kwon, H.

    2013-01-01

    Despite the importance of mangrove ecosystems in the global carbon budget, the relationships between environmental drivers and carbon dynamics in these forests remain poorly understood. This limited understanding is partly a result of the challenges associated with in situ flux studies. Tower-based CO2 eddy covariance (EC) systems are installed in only a few mangrove forests worldwide, and the longest EC record from the Florida Everglades contains less than 9 years of observations. A primary goal of the present study was to develop a methodology to estimate canopy-scale photosynthetic light use efficiency in this forest. These tower-based observations represent a basis for associating CO2 fluxes with canopy light use properties, and thus provide the means for utilizing satellite-based reflectance data for larger scale investigations. We present a model for mangrove canopy light use efficiency utilizing the enhanced green vegetation index (EVI) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) that is capable of predicting changes in mangrove forest CO2 fluxes caused by a hurricane disturbance and changes in regional environmental conditions, including temperature and salinity. Model parameters are solved for in a Bayesian framework. The model structure requires estimates of ecosystem respiration (RE), and we present the first ever tower-based estimates of mangrove forest RE derived from nighttime CO2 fluxes. Our investigation is also the first to show the effects of salinity on mangrove forest CO2 uptake, which declines 5% per each 10 parts per thousand (ppt) increase in salinity. Light use efficiency in this forest declines with increasing daily photosynthetic active radiation, which is an important departure from the assumption of constant light use efficiency typically applied in satellite-driven models. The model developed here provides a framework for estimating CO2 uptake by these forests from reflectance data and information about

  17. Mangrove recruitment after forest disturbance is facilitated by herbaceous species in the Caribbean

    USGS Publications Warehouse

    McKee, K.L.; Rooth, J.E.; Feller, Ilka C.

    2007-01-01

    Plant communities along tropical coastlines are often affected by natural and human disturbances, but little is known about factors influencing recovery. We focused on mangrove forests, which are among the most threatened ecosystems globally, to examine how facilitation by herbaceous vegetation might improve forest restoration after disturbance. We specifically investigated whether recovery of mangrove forests in harsh environments is accelerated by nurse plants and whether the beneficial effects are species-specific. Quantification of standardized effects allowed comparisons across performance parameters and over time for: (1) net effect of each herbaceous species on mangrove survival and growth, (2) effects of pre- and post-establishment factors associated with each herbaceous species, and (3) need for artificial planting to enhance growth or survival of mangrove seedlings. Mangrove recruitment in a clear-cut forest in Belize was accelerated by the presence of Sesuvium portulacastrum (succulent forb) and Distichlis spicata (grass), two coastal species common throughout the Caribbean region. The net effect of herbaceous vegetation was positive, but the magnitude of effects on mangrove survival and growth differed by species. Because of differences in their vegetative structure and other features, species effects on mangroves also varied by mechanism: (1) trapping of dispersing propagules (both species), (2) structural support of the seedling (Distichlis), and/or (3) promotion of survival (Sesuvium) or growth (Distichlis) through amelioration of soil conditions (temperature, aeration). Artificial planting had a stronger positive effect on mangrove survival than did edaphic conditions, but planting enhanced mangrove growth more in Sesuvium than in Distichlis patches. Our study indicates that beneficial species might be selected based on features that provide multiple positive effects and that species comparisons may be improved using standardized effects. Our

  18. Assessment of mangrove forests in the Pacific region using Landsat imagery

    NASA Astrophysics Data System (ADS)

    Bhattarai, Bibek; Giri, Chandra

    2011-01-01

    The information on the mangrove forests for the Pacific region is scarce or outdated. A regional assessment based on a consistent methodology and data sources was needed to understand their true extent. Our investigation offers a regionally consistent, high resolution (30 m), and the most comprehensive mapping of mangrove forests on the islands of American Samoa, Fiji, French Polynesia, Guam, Hawaii, Kiribati, Marshall Islands, Micronesia, Nauru, New Caledonia, Northern Mariana Islands, Palau, Papua New Guinea, Samoa, Solomon Islands, Tonga, Tuvalu, Vanuatu, and Wallis and Futuna Islands for the year 2000. We employed a hybrid supervised and unsupervised image classification technique on a total of 128 Landsat scenes gathered between 1999 and 2004, and validated the results using existing geographic information science (GIS) datasets, high resolution imagery, and published literature. We also draw a comparative analysis with the mangrove forests inventory published by the Food and Agriculture Association (FAO) of the United Nations. Our estimate shows a total of 623755 hectares of mangrove forests in the Pacific region; an increase of 18% from FAO's estimates. Although mangrove forests are disproportionately distributed toward a few larger islands on the western Pacific, they are also significant in many smaller islands.

  19. Fine root respiration in the mangrove Rhizophora mangle over variation in forest stature and nutrient availability.

    PubMed

    Lovelock, Catherine E; Ruess, Roger W; Feller, Ilka C

    2006-12-01

    Root respiration uses a significant proportion of photosynthetically fixed carbon (C) and is a globally important source of C liberated from soils. Mangroves, which are an important and productive forest resource in many tropical and subtropical countries, sustain a high ratio of root to shoot biomass which may indicate that root respiration is a particularly important component in mangrove forest carbon budgets. Mangroves are often exposed to nutrient pollution from coastal waters. Here we assessed the magnitude of fine root respiration in mangrove forests in Belize and investigated how root respiration is influenced by nutrient additions. Respiration rates of excised fine roots of the mangrove, Rhizophora mangle L., were low (4.01 +/- 0.16 nmol CO(2) g(-1) s(-1)) compared to those measured in temperate tree species at similar temperatures. In an experiment where trees where fertilized with nitrogen (N) or phosphorus (P) in low productivity dwarf forests (1-2 m height) and more productive, taller (4- 7 m height) seaward fringing forests, respiration of fine roots did not vary consistently with fertilization treatments or with forest stature. Fine roots of taller fringe trees had higher concentrations of both N and P compared to dwarf trees. Fertilization with P enhanced fine root P concentrations in both dwarf and fringe trees, but reduced root N concentrations compared to controls. Fertilization with N had no effect on root N or P concentrations. Unlike photosynthetic C gain and growth, which is strongly limited by P availability in dwarf forests at this site, fine root respiration (expressed on a mass basis) was variable, but showed no significant enhancements with nutrient additions. Variation in fine root production and standing biomass are, therefore, likely to be more important factors determining C efflux from mangrove sediments than variations in fine root respiration per unit mass. PMID:17169899

  20. How mangrove forests adjust to rising sea level

    USGS Publications Warehouse

    Krauss, Ken W.; McKee, Karen L.; Lovelock, Catherine E.; Cahoon, Donald R.; Saintilan, Neil; Reef, Ruth; Chen, Luzhen

    2014-01-01

    Mangroves are among the most well described and widely studied wetland communities in the world. The greatest threats to mangrove persistence are deforestation and other anthropogenic disturbances that can compromise habitat stability and resilience to sea-level rise. To persist, mangrove ecosystems must adjust to rising sea level by building vertically or become submerged. Mangroves may directly or indirectly influence soil accretion processes through the production and accumulation of organic matter, as well as the trapping and retention of mineral sediment. In this review, we provide a general overview of research on mangrove elevation dynamics, emphasizing the role of the vegetation in maintaining soil surface elevations (i.e. position of the soil surface in the vertical plane). We summarize the primary ways in which mangroves may influence sediment accretion and vertical land development, for example, through root contributions to soil volume and upward expansion of the soil surface. We also examine how hydrological, geomorphological and climatic processes may interact with plant processes to influence mangrove capacity to keep pace with rising sea level. We draw on a variety of studies to describe the important, and often under-appreciated, role that plants play in shaping the trajectory of an ecosystem undergoing change.

  1. How mangrove forests adjust to rising sea level.

    PubMed

    Krauss, Ken W; McKee, Karen L; Lovelock, Catherine E; Cahoon, Donald R; Saintilan, Neil; Reef, Ruth; Chen, Luzhen

    2014-04-01

    Mangroves are among the most well described and widely studied wetland communities in the world. The greatest threats to mangrove persistence are deforestation and other anthropogenic disturbances that can compromise habitat stability and resilience to sea-level rise. To persist, mangrove ecosystems must adjust to rising sea level by building vertically or become submerged. Mangroves may directly or indirectly influence soil accretion processes through the production and accumulation of organic matter, as well as the trapping and retention of mineral sediment. In this review, we provide a general overview of research on mangrove elevation dynamics, emphasizing the role of the vegetation in maintaining soil surface elevations (i.e. position of the soil surface in the vertical plane). We summarize the primary ways in which mangroves may influence sediment accretion and vertical land development, for example, through root contributions to soil volume and upward expansion of the soil surface. We also examine how hydrological, geomorphological and climatic processes may interact with plant processes to influence mangrove capacity to keep pace with rising sea level. We draw on a variety of studies to describe the important, and often under-appreciated, role that plants play in shaping the trajectory of an ecosystem undergoing change.

  2. Mangrove forests: Resilience, protection from tsunamis, and responses to global climate change

    NASA Astrophysics Data System (ADS)

    Alongi, Daniel M.

    2008-01-01

    This review assesses the degree of resilience of mangrove forests to large, infrequent disturbance (tsunamis) and their role in coastal protection, and to chronic disturbance events (climate change) and the future of mangroves in the face of global change. From a geological perspective, mangroves come and go at considerable speed with the current distribution of forests a legacy of the Holocene, having undergone almost chronic disturbance as a result of fluctuations in sea-level. Mangroves have demonstrated considerable resilience over timescales commensurate with shoreline evolution. This notion is supported by evidence that soil accretion rates in mangrove forests are currently keeping pace with mean sea-level rise. Further support for their resilience comes from patterns of recovery from natural disturbances (storms, hurricanes) which coupled with key life history traits, suggest pioneer-phase characteristics. Stand composition and forest structure are the result of a complex interplay of physiological tolerances and competitive interactions leading to a mosaic of interrupted or arrested succession sequences, in response to physical/chemical gradients and landform changes. The extent to which some or all of these factors come into play depends on the frequency, intensity, size, and duration of the disturbance. Mangroves may in certain circumstances offer limited protection from tsunamis; some models using realistic forest variables suggest significant reduction in tsunami wave flow pressure for forests at least 100 m in width. The magnitude of energy absorption strongly depends on tree density, stem and root diameter, shore slope, bathymetry, spectral characteristics of incident waves, and tidal stage upon entering the forest. The ultimate disturbance, climate change, may lead to a maximum global loss of 10-15% of mangrove forest, but must be considered of secondary importance compared with current average annual rates of 1-2% deforestation. A large reservoir of

  3. Tsunami damage reduction performance of a mangrove forest in Banda Aceh, Indonesia inferred from field data and a numerical model

    NASA Astrophysics Data System (ADS)

    Yanagisawa, H.; Koshimura, S.; Miyagi, T.; Imamura, F.

    2010-06-01

    Since the 26 December 2004 Indian Ocean tsunami, the role of mangrove forests as natural defenses protecting coastal communities from tsunami disaster has been highlighted. However, some mangrove forests were destroyed by that tsunami. They are expected to have lost their protective functions. In this study, we develop a fragility function to assess the mangrove trees' vulnerability, expressed as the damage probability of mangrove trees, based on field surveys and numerical modeling of the 2004 Indian Ocean tsunami in Banda Aceh, Indonesia. Based on the fragility function, we reconstruct a numerical model of tsunami inundation including the performance of mangrove forests in terms of reducing tsunami damage. The model reveals that a 10 year old mangrove forest in a 500 m wide area can reduce a tsunami's hydrodynamic force by approximately 70% for an incident wave of 3.0 m inundation depth and a wave period of 40 min at the shoreline. The model also shows, for a tsunami inundation depth of greater than 4 m, that a 10 year old mangrove forest would be mostly destroyed and that it would lose its force reduction capacity. Moreover, approximately 80% of a 30 year old mangrove forest would survive a 5 m tsunami and absorb 50% of the tsunami's hydrodynamic force.

  4. Tidal-scale flow routing and sedimentation in mangrove forests: Combining field data and numerical modelling

    NASA Astrophysics Data System (ADS)

    Horstman, E. M.; Dohmen-Janssen, C. M.; Bouma, T. J.; Hulscher, S. J. M. H.

    2015-01-01

    Tidal-scale biophysical interactions establish particular flow routing and sedimentation patterns in coastal mangroves. Sluggish water flows through the mangrove vegetation and enhanced sediment deposition are essential to maintain these valuable ecosystems, thereby enabling their contribution to coastal protection and stabilization. Spatially explicit field observations of tidal-scale flow routing and sediment deposition were obtained in an elevated mangrove stand dissected by tidal creeks, located in the Trang river estuary at the Thai Andaman coast. An accurate and efficient depth-averaged process-based numerical model of this field site was developed in Delft3D to study the contributions of various biogeophysical mangrove settings to the observed tidal dynamics and to study the impacts of changes of these environmental conditions. The creeks are found to form the major pathway for the tidal inflow during the lower tides, while the sheltered interior of the forest is an effective sediment sink during the higher tides. A numerical sensitivity analysis of the initial response-or adaptive capacity-of the studied mangrove system to instantaneous environmental changes reveals the stable state of the study site: deposition rates are largely imposed by the topography and relative elevation, while they are rather independent of the vegetation density. Deeper inundations of the mangroves favor sheet flows through the forest and spatially averaged deposition rates decrease, particularly when this coincides with decreasing vegetation densities. Moreover, the sediment trapping efficiency is found to reduce significantly with diminishing sediment inputs and with mangrove area losses. These results clearly indicate the sensitivity of mangroves' ecosystem engineering ability-in terms of sedimentation-to climate change and anthropogenic threats.

  5. Micromonospora zhanjiangensis sp. nov., isolated from mangrove forest soil.

    PubMed

    Zhang, Li; Li, Lei; Deng, Zixin; Hong, Kui

    2015-12-01

    A novel actinomycete, designated strain 2902at01T was isolated from soil collected at a mangrove forest in Zhanjiang, Guangdong province, China. The strain was identified using a polyphasic classification method. The 16S rRNA gene sequence of strain 2902at01T showed the highest similarity to Micromonospora equina Y22T (98.3 %) and Micromonospora pattaloongensis TJ2-2T (98.1 %). Phylogenetic analysis based on the gyrB gene sequence also clearly showed that the strain was different from any previously discovered species of the genus Micromonospora. The characteristic whole-cell sugars were ribose and xylose. The cell-wall hydrolysates contained alanine, asparagine, glycine and meso-diaminopimelic acid. MK-10(H6) and MK-10(H8) were the major menaquinones of the novel strain. The predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0 and iso-C16 : 0. The characteristic polar lipids of strain 2902at01T were phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and diphosphatidylglycerol. The DNA G+C content was 70.2 mol%. DNA-DNA hybridization data combined with other physiological and biochemical features could distinguish strain 2902at01T from the reference strains M. equina Y22T and M. pattaloongensis TJ2-2 T. On the basis of these phenotypic and genotypic data, strain 2902at01T represents a novel species of the genus Micromonospora, for which the name Micromonospora zhanjiangensis sp. nov. is proposed. The type strain is 2902at01T ( = CCTCC AA2014018T = DSM 45902T). PMID:26446196

  6. Oceanobacillus halophilum sp. nov. isolated from a mangrove forest soil.

    PubMed

    Tang, Jia; Yang, Guiqin; Wang, Yueqiang; Wu, Chu; Zhou, Shungui

    2014-05-01

    A halophilic, aerobic bacterium, designated GD01(T), was isolated from a mangrove forest soil near the South China Sea. Cells of strain GD01(T) were Gram staining positive, oxidase positive, and catalase positive. The strain was rod shaped and motile by means of peritrichous flagella and produced ellipsoidal endospores. The strain was able to grow with NaCl at concentrations of 0.5-12 % (optimum 3-5 %, w/v), at temperatures of 20-50 °C (optimum 30 °C), and at pH 6.0-8.5 (optimum pH 7.0). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain GD01(T) formed a cluster with O. profundus DSM 18246(T) (96.4 % 16S rRNA gene sequence similarity), O. caeni KCTC 13061(T) (95.4 %), and O. oncorhynchi JCM 12661(T) (94.5 %). The G+C content of strain GD01(T) was 38.7 mol%. The major respiratory quinone was MK-7. The major cellular fatty acids (>5 %) were anteiso-C15:0, iso-C16:0 (13.7 %), anteiso-C17:0 (12.6 %), iso-C15:0 (9.9 %), iso-C14:0 (9.5 %), and C16:0 (5.0 %). The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, glycolipid, four unknown lipids, and four unknown phospholipids. Based on phenotypic characteristics, chemotaxonomic features, and phylogenetic analysis based on 16S rRNA gene sequences, the strain was identified to represent a distinct novel species in the genus Oceanobacillus, and the name proposed is Oceanobacillus halophilum sp. nov. with type train GD01(T) (=CCTCC AB 2012863(T) = KCTC 33101(T)).

  7. Change and fragmentation trends of Zhanjiang mangrove forests in southern China using multi-temporal Landsat imagery (1977-2010)

    NASA Astrophysics Data System (ADS)

    Li, M. S.; Mao, L. J.; Shen, W. J.; Liu, S. Q.; Wei, A. S.

    2013-09-01

    Mangrove forests, which are found in saline coastal environments around the tropical and subtropical latitudes, are among the most productive terrestrial ecosystems in the world and provide valuable ecological and societal goods and services. The objective of this work was to characterize the spatio-temporal changes in mangrove distribution and fragmentation patterns in the Zhanjiang National Mangrove Forest Nature Reserve, Guangdong province of Southern China, from 1977 through 2010. In addition, a major goal was to assess the socio-economic drivers contributing to the chronic changes taking place within and around the mangrove reserve. Land use and land cover data sets were generated for the reserve for multiple years via unsupervised classification using Landsat time series images. Mangrove fragmentation patterns were then assessed with a fragmentation model. Results revealed that the mangrove spatial extent decreased sharply during the period from 1977 to 1991 due to deforestation caused by diverse development programs, particularly shrimp farming. Afterwards, there was a continuous increase in mangrove extent from 1991 to 2010 due to afforestation and conservation efforts. The mangrove fragmentation trends depicted by the fragmentation model had a high degree of correlation with the observed areal changes. Additionally, the recorded dynamics of the local biodiversity (mainly birds) were consistent with the mangrove ecosystem fragmentation trends over time, and different fragmentation components, including interior, perforated and edge, had distinct impacts on the local mangrove-dependent biodiversity. The most effective way to protect and expand the current mangroves include the following: (1) establishment of mangrove natural reserves, (2) forceful implementation of regulations, (3) establishment of educational programs related to mangrove management, (4) deepening international exchanges and cooperation and (5) increasing the transparency of the project

  8. Arbitrary mangrove-to-water ratios imposed on shrimp farmers in Vietnam contradict with the aims of sustainable forest management.

    PubMed

    Baumgartner, Urs; Kell, Shelagh; Nguyen, Tuan Hoang

    2016-01-01

    Worldwide, an estimated 35 % of mangrove forests have been lost between 1980 and 2005-among other reasons due to expansion of aquaculture production systems. In Vietnam, where the total mangrove area decreased from 269,150 ha in 1980 to 157,500 ha in 2000, regulation of such systems in the form of 'mangrove-to-water surface ratio' has had limited success to halt these losses. In this study, a survey of 40 Vietnamese households was conducted in mangrove production forests in Rach Goc commune, Ngoc Hien district, Ca Mau province to understand whether fixed limits on minimal mangrove coverage influence farmers' decisions on mangrove protection. Results of the survey suggest that rural households greatly depend on the incomes generated from shrimp (and crab) farming but that they do not have a share in economic incentives from timber harvests due to lack of full ownership. A strong relationship between mangrove coverage and per pond area income was also revealed. Because farmers are not aware of applicable laws in terms of mangrove-to-water ratios, mangrove coverage tends to shift in favour of higher pond areas. Overall, the findings indicate that regulations in the form of universal mangrove-to-water ratios do not consider the realities of local households, nor are they economically or environmentally useful-rather, they appear to be arbitrary limitations that are not respected by affected communities. The findings question the efficiency of efforts put into stricter enforcement. PMID:27104126

  9. Arbitrary mangrove-to-water ratios imposed on shrimp farmers in Vietnam contradict with the aims of sustainable forest management.

    PubMed

    Baumgartner, Urs; Kell, Shelagh; Nguyen, Tuan Hoang

    2016-01-01

    Worldwide, an estimated 35 % of mangrove forests have been lost between 1980 and 2005-among other reasons due to expansion of aquaculture production systems. In Vietnam, where the total mangrove area decreased from 269,150 ha in 1980 to 157,500 ha in 2000, regulation of such systems in the form of 'mangrove-to-water surface ratio' has had limited success to halt these losses. In this study, a survey of 40 Vietnamese households was conducted in mangrove production forests in Rach Goc commune, Ngoc Hien district, Ca Mau province to understand whether fixed limits on minimal mangrove coverage influence farmers' decisions on mangrove protection. Results of the survey suggest that rural households greatly depend on the incomes generated from shrimp (and crab) farming but that they do not have a share in economic incentives from timber harvests due to lack of full ownership. A strong relationship between mangrove coverage and per pond area income was also revealed. Because farmers are not aware of applicable laws in terms of mangrove-to-water ratios, mangrove coverage tends to shift in favour of higher pond areas. Overall, the findings indicate that regulations in the form of universal mangrove-to-water ratios do not consider the realities of local households, nor are they economically or environmentally useful-rather, they appear to be arbitrary limitations that are not respected by affected communities. The findings question the efficiency of efforts put into stricter enforcement.

  10. Attitudes of local communities towards conservation of mangrove forests: A case study from the east coast of India

    NASA Astrophysics Data System (ADS)

    Badola, Ruchi; Barthwal, Shivani; Hussain, Syed Ainul

    2012-01-01

    The ecological and economic importance of mangrove ecosystems is well established and highlighted by studies establishing a correlation between the protective function of mangroves and the loss of lives and property caused by coastal hazards. Nevertheless, degradation of this ecosystem remains a matter of concern, emphasizing the fact that effective conservation of natural resources is possible only with an understanding of the attitudes and perceptions of local communities. In the present study, we examined the attitudes and perceptions of local communities towards mangrove forests through questionnaire surveys in 36 villages in the Bhitarkanika Conservation Area, India. The sample villages were selected from 336 villages using hierarchical cluster analysis. The study revealed that local communities in the area had positive attitudes towards conservation and that their demographic and socio-economic conditions influenced people's attitudes. Local communities valued those functions of mangrove forests that were directly linked to their wellbeing. Despite human-wildlife conflict, the attitudes of the local communities were not altogether negative, and they were willing to participate in mangrove restoration. People agreed to adopt alternative resources if access to forest resources were curtailed. Respondents living near the forests, who could not afford alternatives, admitted that they would resort to pilfering. Hence, increasing their livelihood options may reduce the pressure on mangrove forests. In contrast with other ecosystems, the linkages of mangrove ecosystem services with local livelihoods and security are direct and tangible. It is therefore possible to develop strong local support for sustainable management of mangrove forests in areas where a positive attitude towards mangrove conservation prevails. The current debates on Reducing Emissions from Deforestation and Forest Degradation (REDD) and payment for ecosystem services provide ample scope for

  11. Assessing impact of climate change on Mundra mangrove forest ecosystem, Gulf of Kutch, western coast of India: a synergistic evaluation using remote sensing

    NASA Astrophysics Data System (ADS)

    Srivastava, Prashant K.; Mehta, Abhinav; Gupta, Manika; Singh, Sudhir Kumar; Islam, Tanvir

    2015-05-01

    Mangrove cover changes have globally raised the apprehensions as the changes influence the coastal climate as well as the marine ecosystem services. The main goals of this research are focused on the monitoring of land cover and mangrove spatial changes particularly for the Mundra forest in the western coast of Gujarat state, India, which is famous for its unique mangrove bio-diversity. The multi-temporal Indian Remote Sensing (IRS) Linear Imaging Self Scanning (LISS)-II (IRS-1B) and III (IRS P6/RESOURCESAT-1) images captured in the year 1994 and 2010 were utilized for the spatio-temporal analysis of the area. The land cover and mangrove density was estimated by a unique hybrid classification which consists of K means unsupervised following maximum likelihood classification (MLC) supervised classification-based approach. The vegetation and non-vegetation layers has been extracted and separated by unsupervised classification technique while the training-based MLC was applied on the separated vegetation and non-vegetation classes to classify them into 11 land use/land cover classes. The climatic variables of the area involves wind, temperature, dew point, precipitation, and mean sea level investigated for the period of 17 years over the site. To understand the driving factors, the anthropogenic variables were also taken into account such as historical population datasets. The overall analysis indicates a significant change in the frequency and magnitude of sea-level rise from 1994 to 2010. The analysis of the meteorological variables indicates a high pressure and changes in mangrove density during the 17 years of time, which reveals that if appropriate actions are not initiated soon, the Mundra mangroves might become the victims of climate change-induced habitat loss. After analyzing all the factors, some recommendations and suggestions are provided for effective mangrove conservation and resilience, which could be used by forest official to protect this precious

  12. Characterization and spatial distribution of mangrove forest types based on ALOS-PALSAR mosaic 25m-resolution in Southeast Asia

    NASA Astrophysics Data System (ADS)

    Darmawan, S.; Takeuchi, W.; Nakazono, E.; Parwati, E.; Dien, V. T.; Oo, K. S.; Wikantika, K.; Sari, D. K.

    2016-06-01

    The objective of this research is to investigate characteristics of mangrove forest types and to identify spatial distribution of mangrove forest based on ALOS PALSAR mosaic 25m- resolution in Southeast Asia. Methodology consists of collecting of ALOS PALSAR image for overall Southeast Asia region, preprocessing include converting DN to NRCS and filtering, collecting regions of interest of mangrove forest in Southeast Asia, plotting, characterization and classification. Result on this research we found characteristics of mangrove forest on HH values around -10.88 dB to -6.65 dB and on HV value around -16.49 dB to -13.26 dB. On polarization of HH which the highest backscattering value is mangrove forest in Preak Piphot River Cambodia, Thái Thủy Thai Binh Vietnam, and Vạn Ninh tp. Móng Cái Quảng Ninh Vietnam whereas the lowest backscattering value is mangrove forest in Thailand area. On polarization of HV which the highest backscattering value is mangrove forest in Preak Piphot River Cambodia, Sorong and Teluk Bintuni Indonesia whereas the lowest backscattering value is mangrove forest in Subang Indonesia, Giao Thiện Giao Thuỷ Nam Định, Vietnam and Puyu Mueng Satun Thailand. Based on characterization, we create a rule criteria for classification of mangrove areas and non mangrove area. Finally we found spatial distribution of mangrove forest based on ALOS PALSAR 25m-resolution in Southeast Asia.

  13. Policy challenges and approaches for the conservation of mangrove forests in Southeast Asia.

    PubMed

    Friess, Daniel A; Thompson, Benjamin S; Brown, Ben; Amir, A Aldrie; Cameron, Clint; Koldewey, Heather J; Sasmito, Sigit D; Sidik, Frida

    2016-10-01

    Many drivers of mangrove forest loss operate over large scales and are most effectively addressed by policy interventions. However, conflicting or unclear policy objectives exist at multiple tiers of government, resulting in contradictory management decisions. To address this, we considered four approaches that are being used increasingly or could be deployed in Southeast Asia to ensure sustainable livelihoods and biodiversity conservation. First, a stronger incorporation of mangroves into marine protected areas (that currently focus largely on reefs and fisheries) could resolve some policy conflicts and ensure that mangroves do not fall through a policy gap. Second, examples of community and government comanagement exist, but achieving comanagement at scale will be important in reconciling stakeholders and addressing conflicting policy objectives. Third, private-sector initiatives could protect mangroves through existing and novel mechanisms in degraded areas and areas under future threat. Finally, payments for ecosystem services (PES) hold great promise for mangrove conservation, with carbon PES schemes (known as blue carbon) attracting attention. Although barriers remain to the implementation of PES, the potential to implement them at multiple scales exists. Closing the gap between mangrove conservation policies and action is crucial to the improved protection and management of this imperiled coastal ecosystem and to the livelihoods that depend on them.

  14. Policy challenges and approaches for the conservation of mangrove forests in Southeast Asia.

    PubMed

    Friess, Daniel A; Thompson, Benjamin S; Brown, Ben; Amir, A Aldrie; Cameron, Clint; Koldewey, Heather J; Sasmito, Sigit D; Sidik, Frida

    2016-10-01

    Many drivers of mangrove forest loss operate over large scales and are most effectively addressed by policy interventions. However, conflicting or unclear policy objectives exist at multiple tiers of government, resulting in contradictory management decisions. To address this, we considered four approaches that are being used increasingly or could be deployed in Southeast Asia to ensure sustainable livelihoods and biodiversity conservation. First, a stronger incorporation of mangroves into marine protected areas (that currently focus largely on reefs and fisheries) could resolve some policy conflicts and ensure that mangroves do not fall through a policy gap. Second, examples of community and government comanagement exist, but achieving comanagement at scale will be important in reconciling stakeholders and addressing conflicting policy objectives. Third, private-sector initiatives could protect mangroves through existing and novel mechanisms in degraded areas and areas under future threat. Finally, payments for ecosystem services (PES) hold great promise for mangrove conservation, with carbon PES schemes (known as blue carbon) attracting attention. Although barriers remain to the implementation of PES, the potential to implement them at multiple scales exists. Closing the gap between mangrove conservation policies and action is crucial to the improved protection and management of this imperiled coastal ecosystem and to the livelihoods that depend on them. PMID:27341487

  15. Habitat creation and biodiversity maintenance in mangrove forests: teredinid bivalves as ecosystem engineers

    PubMed Central

    Michie, Laura; Taylor, Ben W.

    2014-01-01

    Substantial amounts of dead wood in the intertidal zone of mature mangrove forests are tunnelled by teredinid bivalves. When the tunnels are exposed, animals are able to use tunnels as refuges. In this study, the effect of teredinid tunnelling upon mangrove forest faunal diversity was investigated. Mangrove forests exposed to long emersion times had fewer teredinid tunnels in wood and wood not containing teredinid tunnels had very few species and abundance of animals. However, with a greater cross-sectional percentage surface area of teredinid tunnels, the numbers of species and abundance of animals was significantly higher. Temperatures within teredinid-attacked wood were significantly cooler compared with air temperatures, and animal abundance was greater in wood with cooler temperatures. Animals inside the tunnels within the wood may avoid desiccation by escaping the higher temperatures. Animals co-existing in teredinid tunnelled wood ranged from animals found in terrestrial ecosystems including centipedes, crickets and spiders, and animals found in subtidal marine ecosystems such as fish, octopods and polychaetes. There was also evidence of breeding within teredinid-attacked wood, as many juvenile individuals were found, and they may also benefit from the cooler wood temperatures. Teredinid tunnelled wood is a key low-tide refuge for cryptic animals, which would otherwise be exposed to fishes and birds, and higher external temperatures. This study provides evidence that teredinids are ecosystem engineers and also provides an example of a mechanism whereby mangrove forests support intertidal biodiversity and nurseries through the wood-boring activity of teredinids. PMID:25276505

  16. Flux of nitrogen and sediment in a fringe mangrove forest in terminos lagoon, Mexico

    NASA Astrophysics Data System (ADS)

    Rivera-Monroy, Victor H.; Day, John W.; Twilley, Robert R.; Vera-Herrera, Francisco; Coronado-Molina, Carlos

    Fluxes of dissolved inorganic and organic nitrogen, particulate nitrogen, and total suspended sediments were measured in a fringe mangrove forest using the flume technique during a 15-month period in Terminos Lagoon, Mexico. The 12-m flume extended through a fringe forest from a tidal creek to a basin forest. There was a net import of dissolved inorganic nitrogen (NH +4 and NO -2+NO -3) from the creek and basin forest, while particulate (PN) and dissolved organic nitrogen (DON) were exported to the creek and basin forest. The tidal creek was the principal source of NH +4 (0·53 g m -2 year -1) and NO -2+NO -3 (0·08 g m -2 year -1) to the fringe forest, while the basin forest was the main source of total suspended sediments (TSS; 210 g m -2 year -1). Net export of PN occurred from the fringe forest to the tidal creek (0·52 g m -2 year -1) while less PN was exported to the basin forest (0·06 g m -2 year -1). The decrease in salinity during the rainy season indicated that nutrient concentrations in the tidal creek may have been influenced by inputs from rainfall and river discharge to the lagoon. There was a net import of TSS to the fringe forest from both the creek and basin forests, but the net input was 3·5 times higher at the fringe/basin interface. Particulate material exported from the forest during ebb tides generally had a higher C/N ratio than particulate matter imported into the forest on the flooding tide. This suggested that there was a greater nitrogen demand during ebb tide caused by the export of nitrogen-deficient detritus from fringe and basin mangroves. The exchange of nutrients among the tidal creek, the fringe, and basin forests in Estero Pargo is strongly influenced by seasonal weather forcing, such as winter storms, that can influence the magnitude and direction of water flow. The net annual import of inorganic nitrogen and the export of DON and PN suggest, in contrast to other mangrove systems, that the fringe mangrove forest in Estero Pargo

  17. Impacts of Land Cover Change on the Carbon Dynamics in Indonesian Tropical Forested Wetlands- Mangroves and Peat Swamp Forests

    NASA Astrophysics Data System (ADS)

    Kauffman, J. B.; Arifanti, V. B.; Basuki, I.; Kurnianto, S.; Novita, N.; Murdiyarso, D.

    2014-12-01

    Tropical wetland forests including mangroves and lowland peat swamp forests contain among the highest carbon stocks of any ecosystem on the planet. This is largely due to the accumulation of deep organic rich soils which have been sequestering carbon for millennia. Depth of organic layers (peats) can exceed 3 m in mangrove and 10 m in the peat swamp forests. The ecosystem carbon stocks may exceed 2000 Mg/ha in mangroves and 5000 Mg/ha in peat swamp forests. Ironically, rates of deforestation of these tropical forests are among the highest in the tropics. With land cover change comes dramatic shifts in carbon stocks, net ecosystem productivity, and greenhouse gas emissions. Land cover change results in carbon losses of practically all aboveground pools as well as losses arising from soil pools. Based upon studies where we have compared stock changes due to land use the carbon emissions arising from land cover change to shrimp ponds and oil palm have ranged from 800-3000 Mg CO2e/ha. The lowered carbon sequestration rates coupled with increased or similar emissions from decomposition results in an ecosystem shift from a carbon sink to a carbon source. Clearly the large carbon stocks, high rates of deforestation, and large emissions resulting from their degradation suggest that these ecosystems should receive great consideration in climate change mitigation and adaptation strategies.

  18. Mangrove Blue Carbon stocks and change estimation from PolInSAR, Lidar and High Resolution Stereo Imagery combined with Forest Cover change mapping

    NASA Astrophysics Data System (ADS)

    Zalles, V.; Fatoyinbo, T. E.; Simard, M.; Lagomasino, D.; Lee, S. K.; Trettin, C.; Feliciano, E. A.; Hansen, M.; John, P.

    2015-12-01

    Mangroves and tidal wetlands have the highest carbon density among terrestrial ecosystems. Although they only represent 3 % of the total forest area (or 0.01 % of land area), C emissions from mangrove destruction alone at current rates could be equivalent to 10 % of carbon emissions from deforestation. One of the main challenges to implementing carbon mitigation projects is measuring carbon, efficiently, effectively, and safely. In mangroves especially, the extreme difficulty of the terrain has hindered the establishment of sufficient field plots needed to accurately measure carbon on the scale necessary to relate remotely sensed measurements with field measurements at accuracies required for REDD and other C trading mechanisms. In this presentation we will showcase the methodologies for, and the remote sensing products necessary to implement MRV (monitoring, reporting and verification) systems in Coastal Blue Carbon ecosystems. Specifically, we will present new methods to estimate aboveground biomass stocks and change in mangrove ecosystems using remotely sensed data from Interferometric SAR from the TanDEM-X mission, commercial airborne Lidar, High Resolution Stereo-imagery, and timeseries analysis of Landsat imagery in combination with intensive field measurements of above and belowground carbon stocks. Our research is based on the hypothesis that by combining field measurements, commercial airborne Lidar, optical and Pol-InSAR data, we are able to estimate Mangrove blue carbon storage with an error under 20% at the project level and permit the evaluation of UNFCCC mechanisms for the mitigation of carbon emissions from coastal ecosystems.

  19. Airborne Laser Scanning Quantification of Disturbances from Hurricanes and Lightning Strikes to Mangrove Forests in Everglades National Park, USA

    PubMed Central

    Zhang, Keqi; Simard, Marc; Ross, Michael; Rivera-Monroy, Victor H.; Houle, Patricia; Ruiz, Pablo; Twilley, Robert R.; Whelan, Kevin R. T.

    2008-01-01

    Airborne light detection and ranging (LIDAR) measurements derived before and after Hurricanes Katrina and Wilma (2005) were used to quantify the impact of hurricanes and lightning strikes on the mangrove forest at two sites in Everglades National Park (ENP). Analysis of LIDAR measurements covering 61 and 68 ha areas of mangrove forest at the Shark River and Broad River sites showed that the proportion of high tree canopy detected by the LIDAR after the 2005 hurricane season decreased significantly due to defoliation and breakage of branches and trunks, while the proportion of low canopy and the ground increased drastically. Tall mangrove forests distant from tidal creeks suffered more damage than lower mangrove forests adjacent to the tidal creeks. The hurricanes created numerous canopy gaps, and the number of gaps per square kilometer increased from about 400∼500 to 4000 after Katrina and Wilma. The total area of gaps in the forest increased from about 1∼2% of the total forest area to 12%. The relative contribution of hurricanes to mangrove forest disturbance in ENP is at least 2 times more than that from lightning strikes. However, hurricanes and lightning strikes disturb the mangrove forest in a related way. Most seedlings in lightning gaps survived the hurricane impact due to the protection of trees surrounding the gaps, and therefore provide an important resource for forest recovery after the hurricane. This research demonstrated that LIDAR is an effective remote sensing tool to quantify the effects of disturbances such as hurricanes and lightning strikes in the mangrove forest.

  20. Long-term growth and succession in restored and natural mangrove forests in southwestern Florida

    USGS Publications Warehouse

    Proffitt, C.E.; Devlin, D.J.

    2005-01-01

    We compared colonization, growth and succession from 1989 to 2000 in a restored mangrove site and in gap and closed canopy sites in a natural mangrove forest. The restored site was created in 1982 and planted with Rhizophora mangle (???2 m-2) propagules. By 1989, Laguncularia racemosa, with densities up to 12.9 tree m-2, was a dominant in all plots, although densities were greater at edge plots relative to inner plots, and near open water (west plots) relative to further inland (east plots), and in tall mangrove plots relative to scrub plots. Rhizophora mangle (1989 tree densities about 2 m-2) was a codominant in inner and scrub plots, while Avicennia germinans had the lowest densities (<1 tree m-2) in all plots. From 1989 to 2000 L. racemosa experienced reduced recruitment and apparent density-dependent mortality of canopy individuals in plots with high initial densities. Scrub plots experienced high rates of colonization by R. mangle and L. racemosa, rapid growth in height of all species (1989-1996), followed by a dieoff of L. racemosa in later years (1997-2000) as the canopy came to resemble that of tall mangrove plots. Colonization and growth rates were lower in gap and closed canopy regions of the natural forest relative to rates in the restored site. After 11 years, densities of L. racemosa were 10-20x lower and R. mangle slightly less in the gap relative to densities in tall mangrove plots in the restored site at the same age. Although the restored stand had converged with the natural forest by 2000 in terms of some factors such as species richness, vegetation cover, litterfall, and light penetration, trees were still much smaller and stem densities much higher. Full development of mature structure and ecological function will likely require decades more development. ?? Springer 2005.

  1. Leaf litter dynamics and litter consumption in two temperate South Australian mangrove forests

    NASA Astrophysics Data System (ADS)

    Imgraben, Sarah; Dittmann, Sabine

    2008-02-01

    The dynamics and consumption of mangrove litter were investigated in two temperate Avicennia marina dominated forests in South Australia in order to compare production and fate of leaf litter with records from tropical and temperate mangroves. Litterfall was measured using traps over four months in the summer of 2004/2005. Average amount of litter was 2.1 and 3.2 g dwt m - 2 d - 1 , respectively, at the two study sites. Leaves accounted for most of the litterfall, followed by propagules and wood. Litterfall varied over time, and depending on the site and inundation time. The standing stock of leaf litter on the forest floor amounted to 15.5 g m - 2 dwt in March 2005. Decomposition determined by litter bags suggested that leaves lost ˜ 50% of their weight in the first two weeks of exposure, with little further weight loss over longer exposure times. Leaf consumption was investigated with a series of laboratory experiments, using the grapsid crab Helograpsus haswellianus, two snail species ( Salinator fragilis and Austrocochlea concamerata) and the polychaete Neanthes vaalii as potential consumers. There was no consumption of new leaves, and the only significant consumption of aged leaves was found for female H. haswellianus. H. haswellianus consumed 0.1 g dwt d - 1 of senescent leaves in the experiment, equivalent to 0.18 g m - 2 d - 1 in the field (average crab density 1.8 ind m - 2 ), or 9.4% of the average daily leaf litterfall. Experiments with propagules revealed no significant consumption by the crabs. High decomposition and low consumption rates of crabs account for the high accumulation and possible export of leaf litter from these mangroves. Leaf litter availability is not a limiting factor for invertebrate consumers in these temperate mangrove forests, and the low consumption rates imply a major difference in the fate of leaf litter between tropical and temperate mangrove systems.

  2. Differential rates of vertical accretion and elevation change among aerial root types in Micronesian mangrove forests

    NASA Astrophysics Data System (ADS)

    Krauss, K. W.; Allen, J. A.; Cahoon, D. R.

    2003-02-01

    Root systems in mangrove swamps have captured the attention of scientists for decades. Among the postulated roles of root structures include a contribution to the geomorphological stability of mangrove soils through sediment trapping and binding. In this study, we used feldspar marker horizons and sediment pins to investigate the influence of three different functional root types—prop roots in Rhizophora spp., root knees in Bruguiera gymnorrhiza, and pneumatophores in Sonneratia alba—on vertical accretion and elevation change in three mangrove forests in the Federated States of Micronesia. Prop roots facilitated vertical accretion (11.0 mm year -1) more than pneumatophores or bare soil controls (mean, 8.3 mm year -1). Sediment elevation, on the other hand, increased at an average rate of only 1.3 mm year 1 across all root types, with rate differences by root type, ranging from -0.2 to 3.4 mm year -1, being detected within river basins. This investigation demonstrates that prop roots can assist in the settling of suspended sediments from estuarine waters, yet prop root structures are not as successful as pneumatophores in maintaining sediment elevation over 2.5 years. As root densities increase over time, an increase in turbulence-induced erosion and in shallow subsidence as organic peat layers form is expected in Micronesian mangrove forests.

  3. Differential rates of vertical accretion and elevation change among aerial root types in Micronesian mangrove forests

    USGS Publications Warehouse

    Krauss, K.W.; Allen, J.A.; Cahoon, D.R.

    2003-01-01

    Root systems in mangrove swamps have captured the attention of scientists for decades. Among the postulated roles of root structures include a contribution to the geomorphological stability of mangrove soils through sediment trapping and binding. In this study, we used feldspar marker horizons and sediment pins to investigate the influence of three different functional root types - prop roots in Rhizophora spp., root knees in Bruguiera gymnorrhiza, and pneumatophores in Sonneratia alba - on vertical accretion and elevation change in three mangrove forests in the Federated States of Micronesia. Prop roots facilitated vertical accretion (11.0 mm year-1) more than pneumatophores or bare soil controls (mean, 8.3 mm year-1). Sediment elevation, on the other hand, increased at an average rate of only 1.3 mm year-1 across all root types, with rate differences by root type, ranging from -0.2 to 3.4 mm year-1, being detected within river basins. This investigation demonstrates that prop roots can assist in the settling of suspended sediments from estuarine waters, yet prop root structures are not as successful as pneumatophores in maintaining sediment elevation over 2.5 years. As root densities increase over time, an increase in turbulence-induced erosion and in shallow subsidence as organic peat layers form is expected in Micronesian mangrove forests. ?? 2003 Elsevier Science B.V. All rights reserved.

  4. Finescale turbulence and seabed scouring around pneumatophores in a wave-exposed mangrove forest

    NASA Astrophysics Data System (ADS)

    Mullarney, J. C.; Norris, B. K.; Henderson, S. M.; Bryan, K. R.

    2015-12-01

    Coastal mangroves provide a barrier between the coast and lower energy intertidal environments. The presence of mangrove roots (pneumatophores) alters local hydrodynamics by slowing currents, dissipating waves, enhancing within-canopy turbulence, and introducing significant spatial variability to the flow, particularly on the stem scale. To date, limited measurements exist within pneumatophore regions owing to the difficulties of measuring on sufficiently small scales. Hence, little is known about the turbulence controlling sediment transport within these regions. We report unique field observations near the seaward edge of a mangrove forest in the Mekong Delta, Vietnam. This forest is exposed to moderate wave energy (maximum heights of around 1 m), with waves observed to propagate and break up to 100 m inside the forest. Our measurements focus on a rapidly prograding area with a relatively sandy substrate and a gentle topographic slope. We resolved millimeter-scale turbulent flows within and above the pneumatophore canopy. Precise measurements of vegetation densities as a function of height were obtained using photogrammetry techniques. The dissipation rate of turbulent kinetic energy was enhanced at the canopy edge (ɛ ~ 10-4 W/kg), and decreased with distance into the forest (ɛ ~ 10-5 W/kg), although rates remained elevated above values measured on the tidal flat immediately offshore of the mangroves (ɛ ~ 10-6 W/kg). The dependence of turbulence on vegetation characteristics and on the stage of the tidal cycle is explored. The hydrodynamic measurements are then linked with changes in bathymetric features noted after a large wave event. Finer mud sediments were deposited outside the forest on the intertidal mudflat, whereas sandy sediments in the fringe region were significant scoured around regions of dense pneumatophores, and sediment mounds developed in the gaps between pneumatophores.

  5. The reduction effects of mangrove forest on a tsunami based on field surveys at Pakarang Cape, Thailand and numerical analysis

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Hideaki; Koshimura, Shunichi; Goto, Kazuhisa; Miyagi, Toyohiko; Imamura, Fumihiko; Ruangrassamee, Anat; Tanavud, Charlchai

    2009-01-01

    Using an integrated approach including satellite imagery analysis, field measurements, and numerical modeling, we investigated the damage to mangroves caused by the 2004 Indian Ocean tsunami at Pakarang Cape in Pang Nga Province, Thailand. Comparing pre- and post-tsunami satellite imagery of the study area, we found that approximately 70% of the mangrove forest was destroyed by the tsunami. Based on field observations, we found that the survival rate of mangroves increased with increasing stem diameter. Specifically, we found that 72% of Rhizophora trees with a 25-30 cm stem diameter survived the tsunami impact, whereas only 19% with a 15-20 cm stem diameter survived. We simulated the 2004 Indian Ocean tsunami using the nonlinear shallow-water wave theory to reproduce the tsunami inundation flow and investigated the bending moment acting on the mangrove trees. Results of the numerical model showed that the tsunami inundated areas along the mangrove creeks, and its current velocity reached 5.0 m s -1. Based on the field measurements and numerical results, we proposed a fragility function for mangroves, which is the relationship between the probability of damage and the bending stress caused by the maximum bending moment. We refined the numerical model to include the damage probability of mangrove forests using the obtained fragility function to investigate the tsunami reduction effect of mangrove forest. Under simple numerical conditions related to the mangrove forest, ground level, and incident wave, the model showed that a mangrove forest of Rhizophora sp. with a density of 0.2 trees m -2 and a stem diameter of 15 cm in a 400 m wide area can reduce the tsunami inundation depth by 30% when the incident wave is assumed to have a 3.0 m inundation depth and a wave period of 30 min at the shoreline. However, 50% of the mangrove forest is destroyed by a 4.5 m tsunami inundation depth, and most of the mangrove forest is destroyed by a tsunami inundation depth greater

  6. Driving Forces behind Organic Matter and Nutrient Dynamics in a Mangrove Forest Ecosystem in South India

    NASA Astrophysics Data System (ADS)

    Prasad, M. B.

    2005-05-01

    Organic matter is primary carbon source and energy for micro and macro fauna inhabiting in the mangroves, either derived from autochthonous or allochthonous sources. Species composition and sorption capacity of the sediment may alter the organic matter distribution in the mangrove forests. Salinity may also have some impact over the organic matter composition. To understand the organic matter dynamics in the mangrove forest, we conducted a survey on the Pichavaram mangroves lying on the southeast coast of India. We have observed a wide variation in the concentrations of nutrients in the mangrove water in time and space scale. An annual concentration of DOC is 4.19 mg L-1, POC 2.97 mg L-1, DON 3.23 mg L-1 and DOP 0.35 mg L-1. Nutrient dynamics in the mangrove water is significantly influenced by seasonal effects and internal microbial mechanisms. Among the plant species Rhizophora mucronata, R. apiculata and Avicennia marina are the dominant and contributing around 43.41%, 39.55% and 18.13% litter per year respectively. Benthic microbial mineralization of organic matter and total carbon oxidation were studied and found that in Avicennia zone was higher than Rhizophora zone. This was further supported by sulfate reduction. The relationship between salinity and nutrients were analyzed by plot of nutrients versus salinity for different seasons. It has been observed that the net gain of DIN (1.14% m-1) was more than (0.84% m-1), which suggests that conversion of inorganic to organic form was minimal in premonsoon. And the same trend was also observed in monsoon. But the reverse trend was observed in post monsoon (1.5% m-1) and summer (0.65% m-1). Mean C:N ratio increased from 13.6 to 30.2 reflecting the relatively losses of N from the mangrove ecosystem. This is supported by N:Si ratio reduced from 2.49 to 0.33, this may be attributed to relative contribution of diatoms production. Interchanges between nutrient pools were apparent throughout the system. Sediment, and

  7. Mangroves Enhance Reef Fish Abundance at the Caribbean Regional Scale.

    PubMed

    Serafy, Joseph E; Shideler, Geoffrey S; Araújo, Rafael J; Nagelkerken, Ivan

    2015-01-01

    Several studies conducted at the scale of islands, or small sections of continental coastlines, have suggested that mangrove habitats serve to enhance fish abundances on coral reefs, mainly by providing nursery grounds for several ontogenetically-migrating species. However, evidence of such enhancement at a regional scale has not been reported, and recently, some researchers have questioned the mangrove-reef subsidy effect. In the present study, using two different regression approaches, we pursued two questions related to mangrove-reef connectivity at the Caribbean regional scale: (1) Are reef fish abundances limited by mangrove forest area?; and (2) Are mean reef fish abundances proportional to mangrove forest area after taking human population density and latitude into account? Specifically, we tested for Caribbean-wide mangrove forest area effects on the abundances of 12 reef fishes that have been previously characterized as "mangrove-dependent". Analyzed were data from an ongoing, long-term (20-year) citizen-scientist fish monitoring program; coastal human population censuses; and several wetland forest information sources. Quantile regression results supported the notion that mangrove forest area limits the abundance of eight of the 12 fishes examined. Linear mixed-effects regression results, which considered potential human (fishing and habitat degradation) and latitudinal influences, suggested that average reef fish densities of at least six of the 12 focal fishes were directly proportional to mangrove forest area. Recent work questioning the mangrove-reef fish subsidy effect likely reflects a failure to: (1) focus analyses on species that use mangroves as nurseries, (2) consider more than the mean fish abundance response to mangrove forest extent; and/or (3) quantitatively account for potentially confounding human impacts, such as fishing pressure and habitat degradation. Our study is the first to demonstrate at a large regional scale (i.e., the Wider

  8. Mangroves Enhance Reef Fish Abundance at the Caribbean Regional Scale

    PubMed Central

    Serafy, Joseph E.; Shideler, Geoffrey S.; Araújo, Rafael J.; Nagelkerken, Ivan

    2015-01-01

    Several studies conducted at the scale of islands, or small sections of continental coastlines, have suggested that mangrove habitats serve to enhance fish abundances on coral reefs, mainly by providing nursery grounds for several ontogenetically-migrating species. However, evidence of such enhancement at a regional scale has not been reported, and recently, some researchers have questioned the mangrove-reef subsidy effect. In the present study, using two different regression approaches, we pursued two questions related to mangrove-reef connectivity at the Caribbean regional scale: (1) Are reef fish abundances limited by mangrove forest area?; and (2) Are mean reef fish abundances proportional to mangrove forest area after taking human population density and latitude into account? Specifically, we tested for Caribbean-wide mangrove forest area effects on the abundances of 12 reef fishes that have been previously characterized as “mangrove-dependent”. Analyzed were data from an ongoing, long-term (20-year) citizen-scientist fish monitoring program; coastal human population censuses; and several wetland forest information sources. Quantile regression results supported the notion that mangrove forest area limits the abundance of eight of the 12 fishes examined. Linear mixed-effects regression results, which considered potential human (fishing and habitat degradation) and latitudinal influences, suggested that average reef fish densities of at least six of the 12 focal fishes were directly proportional to mangrove forest area. Recent work questioning the mangrove-reef fish subsidy effect likely reflects a failure to: (1) focus analyses on species that use mangroves as nurseries, (2) consider more than the mean fish abundance response to mangrove forest extent; and/or (3) quantitatively account for potentially confounding human impacts, such as fishing pressure and habitat degradation. Our study is the first to demonstrate at a large regional scale (i.e., the Wider

  9. Distribution, Fraction, and Ecological Assessment of Heavy Metals in Sediment-Plant System in Mangrove Forest, South China Sea.

    PubMed

    Li, Ruili; Chai, Minwei; Qiu, Guo Yu

    2016-01-01

    Overlying water, sediment, rhizosphere sediment and mangrove seedlings in the Futian mangrove forest were analyzed for heavy metals. The results showed that mangrove plant acidified sediment and increased organic matter contents. Except for chromium (Cr), nickel (Ni) and copper (Cu) in Aegiceras corniculatum sediment, heavy metals in all sediments were higher than in overlying water, rhizosphere sediment and mangrove root. Heavy metals in Avicennia marina sediments were higher than other sediments. The lower heavy metal biological concentration factors (BCFs) and translocation factors (TFs) indicated that mangrove plant adopted exclusion strategy. The geo-accumulation index, potential ecological risk index and risk assessment code (RAC) demonstrated that heavy metals have posed a considerable ecological risk, especially for cadmium (Cd). Heavy metals (Cr, Ni, Cu and Cd) mainly existed in the reducible fractions. These findings provide actual heavy metal accumulations in sediment-plant ecosystems in mangrove forest, being important in designing the long-term management and conservation policies for managers of mangrove forest. PMID:26800267

  10. Distribution, fraction, and ecological risk assesment of heavy metals in sediment-plant system in mangrove forest, South China Sea

    NASA Astrophysics Data System (ADS)

    LI, R.; Shen, X.; Li, Y. H.; Chai, M. W.; Qiu, G. Y.

    2015-12-01

    Overlying water, sediment, rhizosphere sediment and mangrove seedlings in Futian mangrove forest were analyzed for heavy metals. The results showed that mangrove plant acidified sediment and increased organic matter contents. Except for chromium (Cr), nickel (Ni) and copper (Cu) in Aegiceras corniculatum sediment, heavy metals in all sediments were higher than in overlying water, rhizosphere sediment and mangrove root. Heavy metals in Avicennia marina sediments were higher than other sediments. The lower heavy metal biological concentration factors (BCFs) and translocation factors (TFs) indicated that mangrove plant adopted exclusion strategy. The geo-accumulation index, potential ecological risk index and risk assessment code (RAC) demonstrated that heavy metals have posed a considerable ecological risk, especially for cadmium (Cd). Heavy metals (Cr, Ni, Cu and Cd) mainly existed in the reducible fractions. The RAC values of heavy metals indicated that heavy metals have posed a considerable ecological risk to the biota, especially for Cd. These findings provide actual heavy metal accumulations in sediment-plant ecosystems in mangrove forest, being important in designing the long-term management and conservation policies for managers of mangrove forest.

  11. Distribution, Fraction, and Ecological Assessment of Heavy Metals in Sediment-Plant System in Mangrove Forest, South China Sea

    PubMed Central

    Li, Ruili; Chai, Minwei; Qiu, Guo Yu

    2016-01-01

    Overlying water, sediment, rhizosphere sediment and mangrove seedlings in the Futian mangrove forest were analyzed for heavy metals. The results showed that mangrove plant acidified sediment and increased organic matter contents. Except for chromium (Cr), nickel (Ni) and copper (Cu) in Aegiceras corniculatum sediment, heavy metals in all sediments were higher than in overlying water, rhizosphere sediment and mangrove root. Heavy metals in Avicennia marina sediments were higher than other sediments. The lower heavy metal biological concentration factors (BCFs) and translocation factors (TFs) indicated that mangrove plant adopted exclusion strategy. The geo-accumulation index, potential ecological risk index and risk assessment code (RAC) demonstrated that heavy metals have posed a considerable ecological risk, especially for cadmium (Cd). Heavy metals (Cr, Ni, Cu and Cd) mainly existed in the reducible fractions. These findings provide actual heavy metal accumulations in sediment-plant ecosystems in mangrove forest, being important in designing the long-term management and conservation policies for managers of mangrove forest. PMID:26800267

  12. Standing crop and aboveground biomass partitioning of a dwarf mangrove forest in Taylor River Slough, Florida

    USGS Publications Warehouse

    Coronado-Molina, C.; Day, J.W.; Reyes, E.; Perez, B.C.

    2004-01-01

    The structure and standing crop biomass of a dwarf mangrove forest, located in the salinity transition zone ofTaylor River Slough in the Everglades National Park, were studied. Although the four mangrove species reported for Florida occurred at the study site, dwarf Rhizophora mangle trees dominated the forest. The structural characteristics of the mangrove forest were relatively simple: tree height varied from 0.9 to 1.2 meters, and tree density ranged from 7062 to 23 778 stems haa??1. An allometric relationship was developed to estimate leaf, branch, prop root, and total aboveground biomass of dwarf Rhizophora mangle trees. Total aboveground biomass and their components were best estimated as a power function of the crown area times number of prop roots as an independent variable (Y = B ?? Xa??0.5083). The allometric equation for each tree component was highly significant (p<0.0001), with all r2 values greater than 0.90. The allometric relationship was used to estimate total aboveground biomass that ranged from 7.9 to 23.2 ton haa??1. Rhizophora mangle contributed 85% of total standing crop biomass. Conocarpus erectus, Laguncularia racemosa, and Avicennia germinans contributed the remaining biomass. Average aboveground biomass allocation was 69% for prop roots, 25% for stem and branches, and 6% for leaves. This aboveground biomass partitioning pattern, which gives a major role to prop roots that have the potential to produce an extensive root system, may be an important biological strategy in response to low phosphorus availability and relatively reduced soils that characterize mangrove forests in South Florida.

  13. Biogeochemistry of Nitrous Oxide Production in the Red Mangrove ( Rhizophora mangle) Forest Sediments

    NASA Astrophysics Data System (ADS)

    Bauza, J. F.; Morell, J. M.; Corredor, J. E.

    2002-11-01

    This study was undertaken to quantify the emission and distribution of nitrous oxide and to explore its relation to pertinent physical and chemical parameters in a red mangrove forest located at Magueyes island, Puerto Rico. Rates of N2O evolution, which ranged from 0·05 to 1·4 μmole m-2 h-1 (overall mean=0·50 μmole m-2 h-1), are comparable to those of other previously studied ecosystems. A significant diel cycle of N2O emission was observed. Dissolved N2O concentration averaged 0·15 nmole cm-3 (SD=0·09, n=54) with a range of 0·1 to 0·57 nmole cm-3. Dissolved and exchangeable inorganic nitrogen was present mostly in the form of ammonium (overall mean=212·2 nmole cm-3) with lesser amounts of nitrate (overall mean=29·0 nmole cm-3). Redox potentials in the sediments generally decreased with depth, with a mean value of 377 mV at the sediment surfaces and lower mean value (159 mV) at 10 cm. We have explored the probable sources of N2O in the mangrove forest sediment using correlation analysis between the data obtained in this study and comparing these observations with previous studies of N2O metabolism. Our results, while not excluding the possibility of N2O production through denitrification, indicate that N2O is produced mainly by nitrification in sediments of this mangrove forest.

  14. Vertical accretion and shallow subsidence in a mangrove forest of southwestern Florida, U.S.A

    USGS Publications Warehouse

    Cahoon, D.R.; Lynch, J.C.

    1997-01-01

    Simultaneous measurements of vertical accretion from artificial soil marker horizons and soil elevation change from sedimentation-erosion table (SET) plots were used to evaluate the processes related to soil building in range, basin, and overwash mangrove forests located in a low-energy lagoon which recieves minor inputs of terregenous sediments. Vertical accretion measures reflect the contribution of surficial sedimentation (sediment deposition and surface root growth). Measures of elevation change reflect not only the contributions of vertical accretion but also those of subsurface processes such as compaction, decomposition and shrink-swell. The two measures were used to calculate amounts of shallow subsidence (accretion minus elevation change) in each mangrove forest. The three forest types represent different accretionary envrionments. The basin forest was located behind a natural berm. Hydroperiod here was controlled primarily by rainfall rather than tidal exchange, although the basin flooded during extreme tidal events. Soil accretion here occurred primarily by autochthonous organic matter inputs, and elevation was controlled by accretion and shrink-swell of the substrate apparently related to cycles of flooding-drying and/or root growth-decomposition. This hydrologically-restricted forest did not experience an accretion or elevation deficit relative to sea-level rise. The tidally dominated fringe and overwash island forests accreted through mineral sediment inputs bound in place by plant roots. Filamentous turf algae played an important role in stabilizing loose muds in the fringe forest where erosion was prevalent. Elevation in these high-energy environments was controlled not only by accretion but also by erosion and/or shallow subsidence. The rate of shallow subsidence was consistently 3-4 mm y-1 in the fringe and overwash island forests but was negligible in the basin forest. Hence, the vertical development of mangrove soils was influenced by both

  15. Synergy of Optical and SAR Data for Mapping and Monitoring Mangroves

    NASA Astrophysics Data System (ADS)

    Monzon, A. K.; Reyes, S. R.; Veridiano, R. K.; Tumaneng, R.; De Alban, J. D.

    2016-06-01

    Quantitative information on mangrove cover extents is essential in producing relevant resource management plans and conservation strategies. In the Philippines, mangrove rehabilitation was made a priority in relation to disaster risk response and mitigation following the calamities in the coastal communities during typhoon Haiyan/Yolanda; hence, baseline information on the extent of remaining mangrove cover was essential for effective site interventions. Although mangrove cover maps for the country already exists, analysis of mangrove cover changes were limited to the application of fixed annual deforestation rates due to the challenge of acquiring consistent temporal cloud-free optical satellite data over large landscapes. This study presents an initial analysis of SAR and optical imagery combined with field-based observations for detecting mangrove cover extent and changes through a straightforward graphical approach. The analysis is part of a larger study evaluating the synergistic use of time-series L-band SAR and optical data for mapping and monitoring of mangroves. Image segmentation was implemented on the 25-meter ALOS/PALSAR image mosaics, in which the generated objects were subjected to statistical analysis using the software R. In combination with selected Landsat bands, the class statistics from the image bands were used to generate decision trees and thresholds for the hierarchical image classification. The results were compared with global mangrove cover dataset and validated using collected ground truth data. This study developed an integrated replicable approach for analyzing future radar and optical datasets, essential in national level mangrove cover change monitoring and assessment for long-term conservation targets and strategies.

  16. Transformations of Mangrove Forests in Bahia Magdalena, Baja California Sur, Mexico: Two Decade Results Based on Landsat Imageries

    NASA Astrophysics Data System (ADS)

    Suresh Babu, S.; Abdul Rahaman, S.; Muthushankar, G.; Jonathan, M. P.

    2014-12-01

    Mangrove forests which thrive along the tropical and subtropical regions are the most productive ecosystems in the world with a wide range of ecological and economical services to mankind. With the rapid urbanization across the globe, these forests tend to be destroying at an alarming rate. The area of concern for this study, Bahia Magdalena is very important for the economy of the state as nearly 50% of the artisan fisheries are established in the mangrove zone. Henceforth this study is an attempt for a regional assessment and to accurately quantify the mangroves using LANDSAT imageries for over two decades in Bahia Magdalena, Baja California. Satellite imageries from the year 1986 through 2014 were analysed to assess the prolonged changes taking place in and around the mangrove reserve. Using the estimates of land use/cover for all the years, the spatio - temporal data was validated using ArcGIS software. The results revealed that the spatial extent of mangroves are decreasing until 2005 due to the developmental plans such as tourism, shrimp farming and establishment of industries in this part of the country. During the past 10 years (~ after 2005) there is no much change in the area extent of mangrove reserves due to afforestation and conservation efforts. Thus the unbiased dataset generated may be widely used for an improved understanding of the role of mangrove forests in the socio economic aspects, protection from natural disasters, identify possible areas for conservation, restoration and rehabilitation; and improve estimates of the amount of carbon stored in mangrove vegetation and the associated marine environment. Keywords: Mangroves, LANDSAT, Bahia Magdalena, México.

  17. Landscape analysis and pattern of hurricane impact and circulation on mangrove forests of the everglades

    USGS Publications Warehouse

    Doyle, T.W.; Krauss, K.W.; Wells, C.J.

    2009-01-01

    The Everglades ecosystem contains the largest contiguous tract of mangrove forest outside the tropics that were also coincidentally intersected by a major Category 5 hurricane. Airborne videography was flown to capture the landscape pattern and process of forest damage in relation to storm trajectory and circulation. Two aerial video transects, representing different topographic positions, were used to quantify forest damage from video frame analysis in relation to prevailing wind force, treefall direction, and forest height. A hurricane simulation model was applied to reconstruct wind fields corresponding to the ground location of each video frame and to correlate observed treefall and destruction patterns with wind speed and direction. Mangrove forests within the storm's eyepath and in the right-side (forewind) quadrants suffered whole or partial blowdowns, while left-side (backwind) sites south of the eyewall zone incurred moderate canopy reduction and defoliation. Sites along the coastal transect sustained substantially more storm damage than sites along the inland transect which may be attributed to differences in stand exposure and/or stature. Observed treefall directions were shown to be non-random and associated with hurricane trajectory and simulated forewind azimuths. Wide-area sampling using airborne videography provided an efficient adjunct to limited ground observations and improved our spatial understanding of how hurricanes imprint landscape-scale patterns of disturbance. ?? 2009 The Society of Wetland Scientists.

  18. Controls on mangrove forest-atmosphere carbon dioxide exchanges in western Everglades National Park

    USGS Publications Warehouse

    Barr, Jordan G.; Engel, Vic; Fuentes, Jose D.; Zieman, Joseph C.; O'Halloran, Thomas L.; Smith, Thomas J.; Anderson, Gordon H.

    2010-01-01

    We report on net ecosystem production (NEP) and key environmental controls on net ecosystem exchange (NEE) of carbon dioxide (CO2) between a mangrove forest and the atmosphere in the coastal Florida Everglades. An eddy covariance system deployed above the canopy was used to determine NEE during January 2004 through August 2005. Maximum daytime NEE ranged from -20 to -25 μmol (CO2) m-2 s-1 between March and May. Respiration (Rd) was highly variable (2.81 ± 2.41 μmol (CO2) m-2 s-1), reaching peak values during the summer wet season. During the winter dry season, forest CO2 assimilation increased with the proportion of diffuse solar irradiance in response to greater radiative transfer in the forest canopy. Surface water salinity and tidal activity were also important controls on NEE. Daily light use efficiency was reduced at high (>34 parts per thousand (ppt)) compared to low (d by ~0.9 μmol (CO2) m-2 s-1 and nighttime Rd by ~0.5 μmol (CO2) m-2 s-1. The forest was a sink for atmospheric CO2, with an annual NEP of 1170 ± 127 g C m-2 during 2004. This unusually high NEP was attributed to year-round productivity and low ecosystem respiration which reached a maximum of only 3 g C m-2 d-1. Tidal export of dissolved inorganic carbon derived from belowground respiration likely lowered the estimates of mangrove forest respiration. These results suggest that carbon balance in mangrove coastal systems will change in response to variable salinity and inundation patterns, possibly resulting from secular sea level rise and climate change.

  19. Changes in carbon pool and stand structure of a native subtropical mangrove forest after inter-planting with exotic species Sonneratia apetala.

    PubMed

    Lu, Weizhi; Yang, Shengchang; Chen, Luzhen; Wang, Wenqing; Du, Xiaona; Wang, Canmou; Ma, Yan; Lin, Guangxuan; Lin, Guanghui

    2014-01-01

    In this study, we compared stand structure, biomass and soil carbon pools, and litterfall production between a mixed mangrove forest consisting of Aegiceras corniculatum inter-planted with the exotic Sonneratia apetala and a native monospecific forest dominated by A. corniculatum in the intertidal area of Zhanjiang, Guangdong Province, southeast China. The goal of this study was to test the hypothesis that inter-planting fast growing exotic mangrove S. apetala into subtropical native mangrove forests will significantly increase C sequestration. Although the tree heights and basal diameters of S. apetala were significantly higher than those of A. corniculatum, the density of the 12-year-old S. apetala trees in the mixed forest was much smaller than that of A. corniculatum in the monospecific forest. In contrast to several previous studies on S. apetala forests planted directly on mangrove-free mudflats, the mixed mangrove forest showed no significant difference in either standing biomass or soil carbon pools from the native monospecific mangrove forest (p = 0.294 and 0.073, respectively) twelve years after inter-planting with S. apetala. Moreover, carbon cycling was likely speeded up after inter-planting S. apetala due to higher litterfall input and lower C/N ratio. Thus, inter-planting fast-growing S. apetala into native mangrove forest is not an effective way to increase carbon sequestration in this subtropical mangrove forest. Given that exotic plant species may exert negative impact on native mangrove species and related epifauna, this fast-growing mangrove species is not suitable for mangrove plantation projects aiming mainly at enhancing carbon sequestration.

  20. Changes in Carbon Pool and Stand Structure of a Native Subtropical Mangrove Forest after Inter-Planting with Exotic Species Sonneratia apetala

    PubMed Central

    Lu, Weizhi; Yang, Shengchang; Chen, Luzhen; Wang, Wenqing; Du, Xiaona; Wang, Canmou; Ma, Yan; Lin, Guangxuan; Lin, Guanghui

    2014-01-01

    In this study, we compared stand structure, biomass and soil carbon pools, and litterfall production between a mixed mangrove forest consisting of Aegiceras corniculatum inter-planted with the exotic Sonneratia apetala and a native monospecific forest dominated by A. corniculatum in the intertidal area of Zhanjiang, Guangdong Province, southeast China. The goal of this study was to test the hypothesis that inter-planting fast growing exotic mangrove S. apetala into subtropical native mangrove forests will significantly increase C sequestration. Although the tree heights and basal diameters of S. apetala were significantly higher than those of A. corniculatum, the density of the 12-year-old S. apetala trees in the mixed forest was much smaller than that of A. corniculatum in the monospecific forest. In contrast to several previous studies on S. apetala forests planted directly on mangrove-free mudflats, the mixed mangrove forest showed no significant difference in either standing biomass or soil carbon pools from the native monospecific mangrove forest (p = 0.294 and 0.073, respectively) twelve years after inter-planting with S. apetala. Moreover, carbon cycling was likely speeded up after inter-planting S. apetala due to higher litterfall input and lower C/N ratio. Thus, inter-planting fast-growing S. apetala into native mangrove forest is not an effective way to increase carbon sequestration in this subtropical mangrove forest. Given that exotic plant species may exert negative impact on native mangrove species and related epifauna, this fast-growing mangrove species is not suitable for mangrove plantation projects aiming mainly at enhancing carbon sequestration. PMID:24618793

  1. Toxicity of sediments from a mangrove forest patch in an urban area in Pernambuco (Brazil).

    PubMed

    Oliveira, D D; Souza-Santos, L P; Silva, H K P; Macedo, S J

    2014-06-01

    Industrial and urban residues are discharged every day to the rivers and may arrive at the mangrove forest and prejudice the quality of the environment and the organisms present there. The mangrove forest patch studied is encircled by an urban area of the city of Recife (Brazil) that has approximate 1.5 million inhabitants and is one of the most industrialized centers in Northeast Brazil. The aim of this study was to assess the quality of the sediments of this mangrove patch in terms of metal contamination and ecotoxicology. Samples of surface sediment were collected in six stations for toxicological tests and trace metal determination (Cr, Zn, Mn, Fe, Cu, Pb, Co and Ni), in July and August, 2006 (rainy season); and in January and February 2007 (dry season). Toxicity tests with solid-phase sediments were carried out with the copepod Tisbe biminiensis in order to observe lethal and sub-lethal endpoints and correlate them with chemical data. In June, there were no observed lethal effect, but two stations presented sub-lethal effects. In January, lethal effect occurred in three stations and sub-lethal in one station. The levels for Zn and Cr were at higher levels than international proposed guidelines (NOAA). There was a negative significant correlation between the copepods׳ fecundity, and Zn and Cr concentrations. Therefore, the studied sediments can be considered to have potential toxic to benthos due to the high content of Zn and Cr.

  2. Degradation of mangrove tissues and implications for peat formation in Belizean island forests

    USGS Publications Warehouse

    Middleton, B.A.; McKee, K.L.

    2001-01-01

    1. Macrofaunal leaf consumption and degradation of leaves, woody twigs and roots were studied in mangrove island forests on a Belizean island. Factors influencing accumulation of organic matter deposited both above and below ground in this oligotrophic, autochothonous system were assessed. 2. Leaf degradation rates of Rhizophora mangle (red mangrove), Avicennia germinans (black mangrove) and Laguncularia racemosa (white mangrove) measured in mesh bags, were much faster in the lower than the upper intertidal zone. Mass loss was most rapid in A. germinans but zonal effects were much larger than species differences. 3. Exposure to invertebrates such as crabs and amphipods tripled overall rates of leaf litter breakdown. In the lower intertidal, crabs completely consumed some unbagged leaves within 23 days. Crabs also had an effect on some upper intertidal sites, where degradation of leaves placed in artificial burrows was 2.4 times faster than when placed on the soil surface. 4. In contrast to leaves (27??5% remaining after 230 days), roots and woody twigs were highly refractory (40??2% and 51??6% remaining after 584 and 540 days, respectively). Root degradation did not vary by soil depth, zone or species. Twigs of R. mangle and A. germinans degraded faster on the ground than in the canopy, whereas those of L. racemosa were highly resistant to decay regardless of position. 5. Peat formation at Twin Cays has occurred primarily through deposition and slow turnover of mangrove roots, rather than above-ground tissues that are either less abundant (woody twigs) or more readily removed (leaves).

  3. Hydrological and geomorphological controls on a mangrove forest maintenance during the dry season in the Pacific Coast of Nicaragua

    NASA Astrophysics Data System (ADS)

    Calderon, Heyddy; Weeda, Ruben; Uhlenbrook, Stefan

    2014-05-01

    Hydrological and geomorphological processes are key to mangrove forest growth and development. However, very few studies have been carried out in Central American mangroves to understand their hydrological functioning. Here, a small mangrove forest (0.2 km2) in the South Pacific coast of Nicaragua was investigated to determine sources of freshwater inputs and fluxes of water and nutrients to the sea during the dry season. The general groundwater flow direction is from NE to SW towards the sea. The aquifer is composed of clay and alluvial deposits overlying a fractured shale unit. Shallow groundwater is influenced by a nearby town through infiltration of grey water and pit latrines. Groundwater from the mangrove showed Mn2+ and Fe2+ presence indicating occurrence of denitrification and the role of the mangrove as a nutrient sink. Also, refreshening and salinization processes were identified near the river, indicated by different water facies. Freshwater inputs from precipitation and groundwater discharge maintain adequate salt gradients. The water balance showed an increase of around 619 m3 d-1 in storage during a 22 study period during the dry season, which is reflected by increased hydraulic heads and river stage. Water storage is fostered by low conductivity soil materials and beach ridges parallel to the coast line, whereby the latter occassionally breach due to overtopping of surface water. These conditions favor forest subsistence during the dry season, allowing the mangrove to continue to provide ecological and economic benefits in terms of protection against flooding, habitat for numerous species and tourist attraction.

  4. Carbon sequestration and annual increase of carbon stock in a mangrove forest

    NASA Astrophysics Data System (ADS)

    Ray, R.; Ganguly, D.; Chowdhury, C.; Dey, M.; Das, S.; Dutta, M. K.; Mandal, S. K.; Majumder, N.; De, T. K.; Mukhopadhyay, S. K.; Jana, T. K.

    2011-09-01

    Here we show carbon stock is lower in the tropical mangrove forest than in the terrestrial tropical forest and their annual increase exhibits faster turn over than the tropical forest. Variable for above ground biomass are in decreasing order of importance, breast height diameter ( d), height ( H) and wood density ( ρ). The above ground biomass (AGB) and live below ground biomass (LBGB) held different biomass (39.93 ± 14.05 t C ha -1 versus 9.61 ± 3.37 t C ha -1). Carbon accrual to live biomass (4.71-6.54 Mg C ha -1 a -1) is more than offset by losses from litter fall (4.85 Mg C ha -1 a -1), and carbon sequestration differs significantly between live biomass (1.69 Mg C ha -1 a -1) and sediment (0.012 Mg C ha -1 a -1). Growth specific analyses of taxon density suggest that changes in resource availability and environmental constrains could be the cause of the annual increase in carbon stocks in the Sundarbans mangrove forest in contrast to the disturbance - recovery hypotheses.

  5. Ecuador's mangrove forest carbon stocks: a spatiotemporal analysis of living carbon holdings and their depletion since the advent of commercial aquaculture.

    PubMed

    Hamilton, Stuart E; Lovette, John

    2015-01-01

    In this paper we estimate the living carbon lost from Ecuador's mangrove forests since the advent of export-focused shrimp aquaculture. We use remote sensing techniques to delineate the extent of mangroves and aquaculture at approximately decadal periods since the arrival of aquaculture in each Ecuadorian estuary. We then spatiotemporally calculate the carbon values of the mangrove forests and estimate the amount of carbon lost due to direct displacement by aquaculture. Additionally, we calculate the new carbon stocks generated due to mangrove reforestation or afforestation. This research introduces time and LUCC (land use / land cover change) into the tropical forest carbon literature and examines forest carbon loss at a higher spatiotemporal resolution than in many earlier analyses. We find that 80 percent, or 7,014,517 t of the living carbon lost in Ecuadorian mangrove forests can be attributed to direct displacement of mangrove forests by shrimp aquaculture. We also find that IPCC (Intergovernmental Panel on Climate Change) compliant carbon grids within Ecuador's estuaries overestimate living carbon levels in estuaries where substantial LUCC has occurred. By approaching the mangrove forest carbon loss question from a LUCC perspective, these findings allow for tropical nations and other intervention agents to prioritize and target a limited set of land transitions that likely drive the majority of carbon losses. This singular cause of transition has implications for programs that attempt to offset or limit future forest carbon losses and place value on forest carbon or other forest good and services. PMID:25738286

  6. Ecuador’s Mangrove Forest Carbon Stocks: A Spatiotemporal Analysis of Living Carbon Holdings and Their Depletion since the Advent of Commercial Aquaculture

    PubMed Central

    2015-01-01

    In this paper we estimate the living carbon lost from Ecuador’s mangrove forests since the advent of export-focused shrimp aquaculture. We use remote sensing techniques to delineate the extent of mangroves and aquaculture at approximately decadal periods since the arrival of aquaculture in each Ecuadorian estuary. We then spatiotemporally calculate the carbon values of the mangrove forests and estimate the amount of carbon lost due to direct displacement by aquaculture. Additionally, we calculate the new carbon stocks generated due to mangrove reforestation or afforestation. This research introduces time and LUCC (land use / land cover change) into the tropical forest carbon literature and examines forest carbon loss at a higher spatiotemporal resolution than in many earlier analyses. We find that 80 percent, or 7,014,517 t of the living carbon lost in Ecuadorian mangrove forests can be attributed to direct displacement of mangrove forests by shrimp aquaculture. We also find that IPCC (Intergovernmental Panel on Climate Change) compliant carbon grids within Ecuador’s estuaries overestimate living carbon levels in estuaries where substantial LUCC has occurred. By approaching the mangrove forest carbon loss question from a LUCC perspective, these findings allow for tropical nations and other intervention agents to prioritize and target a limited set of land transitions that likely drive the majority of carbon losses. This singular cause of transition has implications for programs that attempt to offset or limit future forest carbon losses and place value on forest carbon or other forest good and services. PMID:25738286

  7. Ecuador's mangrove forest carbon stocks: a spatiotemporal analysis of living carbon holdings and their depletion since the advent of commercial aquaculture.

    PubMed

    Hamilton, Stuart E; Lovette, John

    2015-01-01

    In this paper we estimate the living carbon lost from Ecuador's mangrove forests since the advent of export-focused shrimp aquaculture. We use remote sensing techniques to delineate the extent of mangroves and aquaculture at approximately decadal periods since the arrival of aquaculture in each Ecuadorian estuary. We then spatiotemporally calculate the carbon values of the mangrove forests and estimate the amount of carbon lost due to direct displacement by aquaculture. Additionally, we calculate the new carbon stocks generated due to mangrove reforestation or afforestation. This research introduces time and LUCC (land use / land cover change) into the tropical forest carbon literature and examines forest carbon loss at a higher spatiotemporal resolution than in many earlier analyses. We find that 80 percent, or 7,014,517 t of the living carbon lost in Ecuadorian mangrove forests can be attributed to direct displacement of mangrove forests by shrimp aquaculture. We also find that IPCC (Intergovernmental Panel on Climate Change) compliant carbon grids within Ecuador's estuaries overestimate living carbon levels in estuaries where substantial LUCC has occurred. By approaching the mangrove forest carbon loss question from a LUCC perspective, these findings allow for tropical nations and other intervention agents to prioritize and target a limited set of land transitions that likely drive the majority of carbon losses. This singular cause of transition has implications for programs that attempt to offset or limit future forest carbon losses and place value on forest carbon or other forest good and services.

  8. Formation, transformation, and removal of aerosol over a tropical mangrove forest

    NASA Astrophysics Data System (ADS)

    Chatterjee, A.; Dutta, C.; Sen, S.; Ghosh, K.; Biswas, N.; Ganguly, D.; Jana, T. K.

    2006-12-01

    A comprehensive size-segregated characterization of the chemical properties (water-soluble inorganic fraction) of the sea-salt aerosol originated from the surf zone at the land-ocean boundary of Sundarban Mangrove forest, NE coast of Bay of Bengal, and an analysis of the relevant meteorological parameters revealed how the combined effect of anthropogenic gases and aerosol advected to the virgin mangrove forest and micrometeorological conditions could change the marine character of the aerosol before the onset of SW monsoon. The average aerosol mass concentration was 99.94 ± 41.9 μg m-3 with production rate of 0.19 μg m-2 s-1 (during January) to 4.29 μg m-2 s-1 (during April) and dry deposition rate of 0.019 μg m-2 s-1 (during January) to 13.21 μg m-2 s-1 (during June). 72.35% of the total aerosol mass was leachable by water, and relatively large concentrations of phosphorus were observed. More chloride depletion from the coarse (2.0 < dp < 10 μm) and nucleation (dp < 0.4 μm) modes compared to the accumulation mode (0.4 < dp < 2.0 μm) was observed in winter (Cl/Na = 0.6023 ± 0.1798), and a reverse trend was observed in summer (Cl/Na = 0.644 ± 0.262). A significant positive correlation was obtained for chloride loss with non-sea-sulphate and nitrate for particles > 2.0 μm. Distributions of Na+, K+, Ca2+, Mg2+, NH4+, Cl-, NO2-, NO3-, SO42-, and PO43- in different size modes were considered to collate their source apportionment. The proximity of Calcutta and Haldia metropolis to the mangrove forest could influence the forest air quality and depositional processes.

  9. Nitrogen limitation of growth and nutrient dynamics in a disturbed mangrove forest, Indian River Lagoon, Florida.

    PubMed

    Feller, Ilka C; Whigham, Dennis F; McKee, Karen L; Lovelock, Catherine E

    2003-02-01

    The objectives of this study were to determine effects of nutrient enrichment on plant growth, nutrient dynamics, and photosynthesis in a disturbed mangrove forest in an abandoned mosquito impoundment in Florida. Impounding altered the hydrology and soil chemistry of the site. In 1997, we established a factorial experiment along a tree-height gradient with three zones, i.e., fringe, transition, dwarf, and three fertilizer treatment levels, i.e., nitrogen (N), phosphorus (P), control, in Mosquito Impoundment 23 on the eastern side of Indian River. Transects traversed the forest perpendicular to the shoreline, from a Rhizophora mangle-dominated fringe through an Avicennia germinans stand of intermediate height, and into a scrub or dwarf stand of A. germinans in the hinterland. Growth rates increased significantly in response to N fertilization. Our growth data indicated that this site is N-limited along the tree-height gradient. After 2 years of N addition, dwarf trees resembled vigorously growing saplings. Addition of N also affected internal dynamics of N and P and caused increases in rates of photosynthesis. These findings contrast with results for a R. mangle-dominated forest in Belize where the fringe is N-limited, but the dwarf zone is P-limited and the transition zone is co-limited by N and P. This study demonstrated that patterns of nutrient limitation in mangrove ecosystems are complex, that not all processes respond similarly to the same nutrient, and that similar habitats are not limited by the same nutrient when different mangrove forests are compared.

  10. Nitrogen limitation of growth and nutrient dynamics in a disturbed mangrove forest, Indian River Lagoon, Florida

    USGS Publications Warehouse

    Feller, Ilka C.; Whigham, D.F.; McKee, K.L.; Lovelock, C.E.

    2003-01-01

    The objectives of this study were to determine effects of nutrient enrichment on plant growth, nutrient dynamics, and photosynthesis in a disturbed mangrove forest in an abandoned mosquito impoundment in Florida. Impounding altered the hydrology and soil chemistry of the site. In 1997, we established a factorial experiment along a tree-height gradient with three zones, i.e., fringe, transition, dwarf, and three fertilizer treatment levels, i.e., nitrogen (N), phosphorus (P), control, in Mosquito Impoundment 23 on the eastern side of Indian River. Transects traversed the forest perpendicular to the shoreline, from a Rhizophora mangle-dominated fringe through an Avicennia germinans stand of intermediate height, and into a scrub or dwarf stand of A. germinans in the hinterland. Growth rates increased significantly in response to N fertilization. Our growth data indicated that this site is N-limited along the tree-height gradient. After 2 years of N addition, dwarf trees resembled vigorously growing saplings. Addition of N also affected internal dynamics of N and P and caused increases in rates of photosynthesis. These findings contrast with results for a R. mangle-dominated forest in Belize where the fringe is N-limited, but the dwarf zone is P-limited and the transition zone is co-limited by N and P. This study demonstrated that patterns of nutrient limitation in mangrove ecosystems are complex, that not all processes respond similarly to the same nutrient, and that similar habitats are not limited by the same nutrient when different mangrove forests are compared.

  11. Commercial activities and subsistence utilization of mangrove forests around the Wouri estuary and the Douala-Edea reserve (Cameroon)

    PubMed Central

    2009-01-01

    Background Worldwide there is growing research interest in the ethnobiology of mangrove forests. Notwithstanding that, little information has been published about ethnobiology of mangrove forests in Cameroon. The aims of this study were a) to analyze the harvesting methods and the local selling of mangrove wood products by loggers in the vicinity of Wouri estuary and b) to investigate the patterns of subsistence uses of mangrove wood products around the Douala-Edea reserve. Methods Semi-structured interviews were conducted with 120 active mangrove loggers in 23 Douala wood markets and 103 households located in three villages (Mbiako, Yoyo I and Yoyo II) close to Douala-Edea reserve. In each of the three densely populated villages, every second household was chosen for sampling while in all markets, mangrove loggers were chosen randomly. In addition, log diameters were measured in each market using a wooden foldable tape measure. A post hoc analysis (Newman-Keuls test) was performed in order to detect the common wood class diameter sold in the Douala wood markets. Results The analysis of the loggers' survey data has shown that large logs of Rhizophora with diameter greater than 40 cm were common in the Douala wood markets and were more closely associated with loggers who used chainsaws. In addition to the general mangroves wood products selling, the analysis on a subsistence level (households' survey) suggests the local population's dependence on mangroves, with multiple uses of Rhizophora racemosa Meyer, R. harrisonii Leechman, Avicennia germinans L. Stearn., Laguncularia racemosa Gaertn. f. and Conocarpus erectus L. timbers for furniture, fences, smoking fish, and fuelwood. Finally, Nypa fruticans (Thunb.) Wurmb. leaves were used as thatching material for house walls and roofs. Conclusion Our findings revealed that big logs of Rhizophora were commonly sold by the loggers. A majority of loggers (60%) reported that mangrove marketed wood constitute a principal

  12. Modifications to the bottomless lift net for sampling nekton in tidal mangrove forests

    USGS Publications Warehouse

    McIvor, C.C.; Silverman, N.L.

    2010-01-01

    Sampling fishes in vegetated intertidal wetlands is logistically challenging. We modified the 2 ?? 3-m2 bottomless lift net developed for sampling nekton (fish and decapod crustaceans) on the surface of salt marshes for use in tidal mangrove forests with a woody (as opposed to herbaceous) underground root system. As originally designed (Rozas, Mar Ecol Prog Ser 89:287-292, 1992), the lift net was buried directly in the marsh substrate. The net was raised at slack high tide thereby encircling nekton within the enclosed area. A chain-line on the net bottom prevented escape under the net once deployed. However, when we used this same design in tidal mangrove forests, the extensive woody roots and occasional slumping sediments resulted in uneven trenches that could not be cleared effectively during sample recovery. We made 3 modifications to the original net design: (i) lined the peat trenches with aluminum channels of uniform width and depth; (ii) replaced the previous chain-line with Velcro closures that directly attached the net to the inner face of the outer wall of the aluminum channel; and (iii) removed the subtidal pan previously used for concentrating the enclosed nekton at low tide, and filled in those depressions with on-site peat. In the modified version, the aluminum trench became the only subtidal refuge available to nekton, and it was from here that we collected the sample after the forest drained. These modifications permitted high clearing efficiency (93-100%) of fin-clipped individuals of two common species of estuarine resident fishes, Kryptolebias marmoratus (mangrove rivulus) and Bathygobius soporator (frillfin goby). Additionally, the density estimates of grass shrimp (Palaemonetes spp.) increased 10-fold post-modification. ?? 2010 US Government.

  13. Community structure at two compartments of a disturbed mangrove forests at Pulau Langkawi

    NASA Astrophysics Data System (ADS)

    Norilani, W. I. Wan; Juliana, W. A. Wan; Salam, Muhamad Razali; Latiff, A.

    2014-09-01

    A study on floristic composition and estimation of above ground biomass of trees was carried out in two areas of disturbed mangroves at Kisap Forest Reserve, Pulau Langkawi. Two compartments that were selected was based on the different types of disturbances, i.e. compartment 5 (C5) was disrupted by human harvesting activities of mangrove trees for charcoal production, while compartment 7 (C7) was naturally disturbed from lightning strikes. In C5, a total of 1,217 trees measuring 1 cm DBH and above were enumerated in the plots of 0.25 ha which included 7 species and 5 genera in 3 families, i.e. Rhizophoraceae, Meliaceae and Avicenniaceae. In C7, a total of 390 individual trees of 8 species, 5 genera and 3 families were recorded. The three families recorded in C7 were also common in C5. Rhizophoraceae was recorded as the family with highest density in both compartments. Ceriops tagal had the highest density in C5, while Rhizophora apiculata was the most prominent species in the C7. Total basal area that represents tree coverage showed C5 had a value of 7.767 m2/ha with C. tagal as the major contributor at 5.022m2/ha. Total coverage in C7 was 18.184 m2/ha that was mostly contributed by R. apiculata at 11.135 m2/ha. Ceriops tagal (22.41 t/ha) and R. apiculata (111.75 t/ha), were the main contributors to the total biomass in C5 (37.34 t/ha) and C7 (162.29 t/ha), respectively. The distribution of individuals of six tree size classes in C7 was homogenous compared to that of C5, which had more saplings. In this study, the total biomass indicated that anthropogenic activities resulted in lower productivity of forest compared to natural disturbance. Therefore, conservation efforts of mangrove forest should be enhance in the management of mangrove forest in Pulau Langkawi.

  14. Utilizing NASA Earth Observations to Monitor, Map, and Forecast Mangrove Extent and Deforestation in Myanmar for Enhanced Conservation

    NASA Astrophysics Data System (ADS)

    Ferraro, C. P.; Jensen, D.; Disla, C.

    2013-12-01

    Mangrove ecosystems offer several significant services including providing habitat and spawning grounds for a diverse range of species, protecting coastal communities from storms and other natural disasters, and contributing resources and income for local residents. Currently, Myanmar is undergoing a period of rapid economic development which has led to increased pressure on the extensive mangrove habitat in the Ayeyarwady River Delta in southern Myanmar. In this study, we partnered with the Smithsonian Conservation Biology Institute to examine changes to mangrove extent between 1989 and 2013 using Landsat 4, 7, and 8 imagery in combination with a Digital Elevation Model (DEM) generated from ASTER stereoscopic imagery. Classification was performed using a Random Forests model and accuracy was assessed using higher resolution ASTER imagery and local expertise on mangrove distribution. Results show a large and consistent decline in mangrove cover during the study period. The data provided by this assessment was subsequently used to forecast potential vulnerability and changes to mangrove habitat up to 2030. A multi-layered perceptron was used to model transition potentials for vulnerability forecasting. Forest managers in Myanmar will be able to use the mangrove change maps and forecasts to evaluate current policies and focus future ones to maximize effectiveness. Data and methodology resulting from this project will be useful for future mangrove and land-cover mapping projects in this region.

  15. Applying Climate Compatible Development and economic valuation to coastal management: A case study of Kenya's mangrove forests.

    PubMed

    Huxham, Mark; Emerton, Lucy; Kairo, James; Munyi, Fridah; Abdirizak, Hassan; Muriuki, Tabitha; Nunan, Fiona; Briers, Robert A

    2015-07-01

    Mangrove forests are under global pressure. Habitat destruction and degradation persist despite longstanding recognition of the important ecological functions of mangroves. Hence new approaches are needed to help stakeholders and policy-makers achieve sound management that is informed by the best science. Here we explore how the new policy concept of Climate Compatible Development (CCD) can be applied to achieve better outcomes. We use economic valuation approaches to combine socio-economic data, projections of forest cover based on quantitative risk mapping and storyline scenario building exercises to articulate the economic consequences of plausible alternative future scenarios for the mangrove forests of the South Kenya coast, as a case study of relevance to many other areas. Using data from 645 household surveys, 10 focus groups and 74 interviews conducted across four mangrove sites, and combining these with information on fish catches taken at three landing sites, a mangrove carbon trading project and published data allowed us to make a thorough (although still partial) economic valuation of the forests. This gave a current value of the South Coast mangroves of USD 6.5 million, or USD 1166 ha(-1), with 59% of this value on average derived from regulating services. Quantitative risk mapping, projecting recent trends over the next twenty years, suggests a 43% loss of forest cover over that time with 100% loss at the most vulnerable sites. Much of the forest lost between 1992 and 2012 has not been replaced by high value alternative land uses hence restoration of these areas is feasible and may not involve large opportunity costs. We invited thirty eight stakeholders to develop plausible storyline scenarios reflecting Business as Usual (BAU) and CCD - which emphasises sustainable forest conservation and management - in twenty years time, drawing on local and regional expert knowledge of relevant policy, social trends and cultures. Combining these scenarios with

  16. Applying Climate Compatible Development and economic valuation to coastal management: A case study of Kenya's mangrove forests.

    PubMed

    Huxham, Mark; Emerton, Lucy; Kairo, James; Munyi, Fridah; Abdirizak, Hassan; Muriuki, Tabitha; Nunan, Fiona; Briers, Robert A

    2015-07-01

    Mangrove forests are under global pressure. Habitat destruction and degradation persist despite longstanding recognition of the important ecological functions of mangroves. Hence new approaches are needed to help stakeholders and policy-makers achieve sound management that is informed by the best science. Here we explore how the new policy concept of Climate Compatible Development (CCD) can be applied to achieve better outcomes. We use economic valuation approaches to combine socio-economic data, projections of forest cover based on quantitative risk mapping and storyline scenario building exercises to articulate the economic consequences of plausible alternative future scenarios for the mangrove forests of the South Kenya coast, as a case study of relevance to many other areas. Using data from 645 household surveys, 10 focus groups and 74 interviews conducted across four mangrove sites, and combining these with information on fish catches taken at three landing sites, a mangrove carbon trading project and published data allowed us to make a thorough (although still partial) economic valuation of the forests. This gave a current value of the South Coast mangroves of USD 6.5 million, or USD 1166 ha(-1), with 59% of this value on average derived from regulating services. Quantitative risk mapping, projecting recent trends over the next twenty years, suggests a 43% loss of forest cover over that time with 100% loss at the most vulnerable sites. Much of the forest lost between 1992 and 2012 has not been replaced by high value alternative land uses hence restoration of these areas is feasible and may not involve large opportunity costs. We invited thirty eight stakeholders to develop plausible storyline scenarios reflecting Business as Usual (BAU) and CCD - which emphasises sustainable forest conservation and management - in twenty years time, drawing on local and regional expert knowledge of relevant policy, social trends and cultures. Combining these scenarios with

  17. Use of archive aerial photography for monitoring black mangrove populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted on the south Texas Gulf Coast to evaluate archive aerial color-infrared (CIR) photography combined with supervised image analysis techniques to quantify changes in black mangrove [Avicennia germinans (L.) L.] populations over a 26-year period. Archive CIR film from two study si...

  18. Changes in mass and nutrient content of wood during decomposition in a south Florida mangrove forest

    USGS Publications Warehouse

    Romero, L.M.; Smith, T. J.; Fourqurean, J.W.

    2005-01-01

    1 Large pools of dead wood in mangrove forests following disturbances such as hurricanes may influence nutrient fluxes. We hypothesized that decomposition of wood of mangroves from Florida, USA (Avicennia germinans, Laguncularia racemosa and Rhizophora mangle), and the consequent nutrient dynamics, would depend on species, location in the forest relative to freshwater and marine influences and whether the wood was standing, lying on the sediment surface or buried. 2 Wood disks (8-10 cm diameter, 1 cm thick) from each species were set to decompose at sites along the Shark River, either buried in the sediment, on the soil surface or in the air (above both the soil surface and high tide elevation). 3 A simple exponential model described the decay of wood in the air, and neither species nor site had any effect on the decay coefficient during the first 13 months of decomposition. 4 Over 28 months of decomposition, buried and surface disks decomposed following a two-component model, with labile and refractory components. Avicennia germinans had the largest labile component (18 ?? 2% of dry weight), while Laguncularia racemosa had the lowest (10 ?? 2%). Labile components decayed at rates of 0.37-23.71% month -1, while refractory components decayed at rates of 0.001-0.033% month-1. Disks decomposing on the soil surface had higher decay rates than buried disks, but both were higher than disks in the air. All species had similar decay rates of the labile and refractory components, but A. germinans exhibited faster overall decay because of a higher proportion of labile components. 5 Nitrogen content generally increased in buried and surface disks, but there was little change in N content of disks in the air over the 2-year study. Between 17% and 68% of total phosphorus in wood leached out during the first 2 months of decomposition, with buried disks having the greater losses, P remaining constant or increasing slightly thereafter. 6 Newly deposited wood from living trees was

  19. Examining the ecosystem health and sustainability of the world's largest mangrove forest using multi-temporal MODIS products.

    PubMed

    Ishtiaque, Asif; Myint, Soe W; Wang, Chuyuan

    2016-11-01

    Sweeping across Bangladesh and India, the Sundarbans forest is the world's largest contiguous mangrove forest. Although the human population density is high at the edge, Sundarbans has not encountered significant areal transformation in the last four decades. However, we argue that forest degradation can occur discontinuously within the forest without alteration of the entire forest area. In this paper, we used MODIS land products to compare the spatiotemporal ecological dynamics of the Bangladesh and Indian part of this mangrove forest between 2000 and 2010. We used the following 5 ecological parameters for our analysis: the Percent Tree Cover (PTC), Enhanced Vegetation Index (EVI), Net Primary Productivity (NPP), Leaf Area Index (LAI), and Evapotranspiration (ET). Our pixel-based time-series trend analysis for each MODIS image stack, using an ordinary least square (OLS) regression method, showed that forest degradation is happening in fragmented parcels within the forest. The degradation rate is comparatively higher in the Bangladesh part than in the Indian part of Sundarbans. Compartments 8, 10, 12, and 15 in the Bangladesh part, in particular, show high degradation, while compartment 48 and the southern edge of 45 show slight increases in PTC or EVI. Forest degradation in the Indian part of the forest is evident in the National Park and Reserve Forest blocks; however, no substantial degradation is evident in the western section. We have identified certain anthropogenic stressors (i.e., oil pollution, shrimp farming) and natural stressors (i.e., increased salinity, cyclones, forest fire) which might be responsible for the observed degradation. We have provided sustainable planning options and policy transformation alternatives for those areas under pressure from these stressors. We anticipate that our analysis of forest degradation will help management agencies, conservators, and policy makers achieve better management of this world's largest mangrove forest for

  20. Examining the ecosystem health and sustainability of the world's largest mangrove forest using multi-temporal MODIS products.

    PubMed

    Ishtiaque, Asif; Myint, Soe W; Wang, Chuyuan

    2016-11-01

    Sweeping across Bangladesh and India, the Sundarbans forest is the world's largest contiguous mangrove forest. Although the human population density is high at the edge, Sundarbans has not encountered significant areal transformation in the last four decades. However, we argue that forest degradation can occur discontinuously within the forest without alteration of the entire forest area. In this paper, we used MODIS land products to compare the spatiotemporal ecological dynamics of the Bangladesh and Indian part of this mangrove forest between 2000 and 2010. We used the following 5 ecological parameters for our analysis: the Percent Tree Cover (PTC), Enhanced Vegetation Index (EVI), Net Primary Productivity (NPP), Leaf Area Index (LAI), and Evapotranspiration (ET). Our pixel-based time-series trend analysis for each MODIS image stack, using an ordinary least square (OLS) regression method, showed that forest degradation is happening in fragmented parcels within the forest. The degradation rate is comparatively higher in the Bangladesh part than in the Indian part of Sundarbans. Compartments 8, 10, 12, and 15 in the Bangladesh part, in particular, show high degradation, while compartment 48 and the southern edge of 45 show slight increases in PTC or EVI. Forest degradation in the Indian part of the forest is evident in the National Park and Reserve Forest blocks; however, no substantial degradation is evident in the western section. We have identified certain anthropogenic stressors (i.e., oil pollution, shrimp farming) and natural stressors (i.e., increased salinity, cyclones, forest fire) which might be responsible for the observed degradation. We have provided sustainable planning options and policy transformation alternatives for those areas under pressure from these stressors. We anticipate that our analysis of forest degradation will help management agencies, conservators, and policy makers achieve better management of this world's largest mangrove forest for

  1. Nitrogen vs. phosphorus limitation across an ecotonal gradient in a mangrove forest

    USGS Publications Warehouse

    Feller, Ilka C.; McKee, K.L.; Whigham, D.F.; O'Neill, J.P.

    2003-01-01

    Mangrove forests are characterized by distinctive tree-height gradients that reflect complex spatial, within-stand differences in environmental factors, including nutrient dynamics, salinity, and tidal inundation, across narrow gradients. To determine patterns of nutrient limitation and the effects of nutrient availability on plant growth and within-stand nutrient dynamics, we used a factorial experiment with three nutrient treatment levels (control, N, P) and three zones along a tree-height gradient (fringe, transition, dwarf) on offshore islands in Belize. Transects were laid out perpendicular to the shoreline across a mangrove forest from a fringe stand along the seaward edge, through a stand of intermediate height, into a dwarf stand in the interior of the island. At three sites, three trees were fertilized per zone for 2 yr. Although there was spatial variability in response, growth by R. mangle was generally nitrogen (N) -limited in the fringe zone; phosphorus (P) -limited in the dwarf zone; and, N- and/or P-limited in the transition zone. Phosphorus-resorption efficiency decreased in all three zones, and N-resorption efficiency increased in the dwarf zone in response to P enrichment. The addition of N had no effect on either P or N resorption efficiencies. Belowground decomposition was increased by P enrichment in all zones, whereas N enrichment had no effect. This study demonstrated that essential nutrients are not uniformly distributed within mangrove ecosystems; that soil fertility can switch from conditions of N to P limitation across narrow ecotonal gradients; and, that not all ecological processes respond similarly to, or are limited by, the same nutrient.

  2. Mapping disturbances in a mangrove forest using multi-date landsat TM imagery.

    PubMed

    Kovacs, J M; Wang, J; Blanco-Correa, M

    2001-05-01

    To evaluate the accounts of local fishermen, Landsat TM images (1986, 1993, 1999) were examined to assess potential losses in the mangrove forests of the Teacapán-Agua Brava lagoon system, Mexico. A binary change mask derived from image differencing of a band 4/3 ratio was employed to calculate any changes within this forested wetland. The results indicate that by 1986 approximately 18% (or 86 km2) of the mangrove area under study was either dead or in poor condition. The majority of this damage had occurred in the eastern section of the Agua Brava basin, which coincides, with the reports of the elderly fishermen. Examination of aerial photographs from 1970 revealed no adverse impacts in this area and would suggest, as postulated by the fishermen and other scientists, that modifications in environmental conditions following the opening of a canal, Cuautlá canal, in 1972 may have initiated the large-scale mortality. Although these areas of impact are still developing, the results from the satellite data indicate that the majority of the more recent changes are occurring elsewhere in the system. Obvious in the 1999 satellite data, but not so in the 1993, are large areas of mangrove degradation in the northern section of the Teacapán region. In the Agua Brava basin, the more recent transformations are appearing on the western side of the basin. Since long-term records of environmental conditions are absent, it is difficult to determine why these latest changes are occurring or even if the earlier losses were the result of the canal. Potential agents of change that have recently been observed include a hurricane, a second canal, and the uncontrolled expansion of the Cuautlá canal since 1994.

  3. Is Matang Mangrove Forest in Malaysia Sustainably Rejuvenating after More than a Century of Conservation and Harvesting Management?

    PubMed Central

    Van der Stocken, Tom; Quispe Zuniga, Melissa; Mohd-Lokman, Husain; Sulong, Ibrahim

    2014-01-01

    Matang Mangrove Forest Reserve (MMFR) in Peninsular Malaysia is under systematic management since 1902 and still considered as the best managed mangrove forest in the world. The present study on silvimetrics assessed the ongoing MMFR forest management, which includes a first thinning after 15 years, a second thinning after 20 years and clear-felling of 30-year old forest blocks, for its efficiency and productivity in comparison to natural mangroves. The estimated tree structural parameters (e.g. density, frequency) from three different-aged mangrove blocks of fifteen (MF15), twenty (MF20), and thirty (MF30) years old indicated that Bruguiera and Excoecaria spp. did not constitute a significant proportion of the vegetation (<5%), and hence the results focused majorly on Rhizophora apiculata. The density of R. apiculata at MF15, MF20 and MF30 was 4,331, 2,753 and 1,767 stems ha−1, respectively. In relation to ongoing practices of the artificial thinnings at MMFR, the present study suggests that the first thinning could be made earlier to limit the loss of exploitable wood due to natural thinning. In fact, the initial density at MF15 was expected to drop down from 6,726 to 1,858 trees ha−1 before the first thinning. Therefore the trees likely to qualify for natural thinning, though having a smaller stem diameter, should be exploited for domestic/commercial purposes at an earlier stage. The clear-felling block (MF30) with a maximum stem diameter of 30 cm was estimated to yield 372 t ha−1 of the above-ground biomass and suggests that the mangrove management based on a 30-year rotation is appropriate for the MMFR. Since Matang is the only iconic site that practicing sustainable wood production, it could be an exemplary to other mangrove locations for their improved management. PMID:25144689

  4. Is Matang Mangrove Forest in Malaysia sustainably rejuvenating after more than a century of conservation and harvesting management?

    PubMed

    Goessens, Arnaud; Satyanarayana, Behara; Van der Stocken, Tom; Quispe Zuniga, Melissa; Mohd-Lokman, Husain; Sulong, Ibrahim; Dahdouh-Guebas, Farid

    2014-01-01

    Matang Mangrove Forest Reserve (MMFR) in Peninsular Malaysia is under systematic management since 1902 and still considered as the best managed mangrove forest in the world. The present study on silvimetrics assessed the ongoing MMFR forest management, which includes a first thinning after 15 years, a second thinning after 20 years and clear-felling of 30-year old forest blocks, for its efficiency and productivity in comparison to natural mangroves. The estimated tree structural parameters (e.g. density, frequency) from three different-aged mangrove blocks of fifteen (MF15), twenty (MF20), and thirty (MF30) years old indicated that Bruguiera and Excoecaria spp. did not constitute a significant proportion of the vegetation (<5%), and hence the results focused majorly on Rhizophora apiculata. The density of R. apiculata at MF15, MF20 and MF30 was 4,331, 2,753 and 1,767 stems ha(-1), respectively. In relation to ongoing practices of the artificial thinnings at MMFR, the present study suggests that the first thinning could be made earlier to limit the loss of exploitable wood due to natural thinning. In fact, the initial density at MF15 was expected to drop down from 6,726 to 1,858 trees ha(-1) before the first thinning. Therefore the trees likely to qualify for natural thinning, though having a smaller stem diameter, should be exploited for domestic/commercial purposes at an earlier stage. The clear-felling block (MF30) with a maximum stem diameter of 30 cm was estimated to yield 372 t ha(-1) of the above-ground biomass and suggests that the mangrove management based on a 30-year rotation is appropriate for the MMFR. Since Matang is the only iconic site that practicing sustainable wood production, it could be an exemplary to other mangrove locations for their improved management.

  5. Is Matang Mangrove Forest in Malaysia sustainably rejuvenating after more than a century of conservation and harvesting management?

    PubMed

    Goessens, Arnaud; Satyanarayana, Behara; Van der Stocken, Tom; Quispe Zuniga, Melissa; Mohd-Lokman, Husain; Sulong, Ibrahim; Dahdouh-Guebas, Farid

    2014-01-01

    Matang Mangrove Forest Reserve (MMFR) in Peninsular Malaysia is under systematic management since 1902 and still considered as the best managed mangrove forest in the world. The present study on silvimetrics assessed the ongoing MMFR forest management, which includes a first thinning after 15 years, a second thinning after 20 years and clear-felling of 30-year old forest blocks, for its efficiency and productivity in comparison to natural mangroves. The estimated tree structural parameters (e.g. density, frequency) from three different-aged mangrove blocks of fifteen (MF15), twenty (MF20), and thirty (MF30) years old indicated that Bruguiera and Excoecaria spp. did not constitute a significant proportion of the vegetation (<5%), and hence the results focused majorly on Rhizophora apiculata. The density of R. apiculata at MF15, MF20 and MF30 was 4,331, 2,753 and 1,767 stems ha(-1), respectively. In relation to ongoing practices of the artificial thinnings at MMFR, the present study suggests that the first thinning could be made earlier to limit the loss of exploitable wood due to natural thinning. In fact, the initial density at MF15 was expected to drop down from 6,726 to 1,858 trees ha(-1) before the first thinning. Therefore the trees likely to qualify for natural thinning, though having a smaller stem diameter, should be exploited for domestic/commercial purposes at an earlier stage. The clear-felling block (MF30) with a maximum stem diameter of 30 cm was estimated to yield 372 t ha(-1) of the above-ground biomass and suggests that the mangrove management based on a 30-year rotation is appropriate for the MMFR. Since Matang is the only iconic site that practicing sustainable wood production, it could be an exemplary to other mangrove locations for their improved management. PMID:25144689

  6. Seed predation by insects in tropical mangrove forests: extent and effects on seed viability and the growth of seedlings.

    PubMed

    Robertson, A I; Giddins, R; Smith, T J

    1990-06-01

    Although insects are known to be important seed predators in most terrestrial forests, their role in marine tidal (mangrove) forests has not been examined. Surveys at 12 sites in tropical Australia showed that between 3.1 and 92.7 percent of the seeds or propagules of 12 mangrove tree species had been attacked by insects. Seeds/propagules of six species (Avicennia marina, Bruguiera gymnorrhiza, B. parviflora, Heritiera littoralis, Xylocarpus australasicus and X. granatum) showed consistently high (>40%) levels of insect damage. Greater than 99% of H. littoralis seeds were attacked by insect predators. The survival and subsequent growth in height and biomass of insect-damaged and non-damaged control seeds/propagules of eight mangrove species were compared in shadehouse experiments. Mangrove species fell into 4 groups with regard to the effect of insect predators on their seeds and seedlings. Xylocarpus australasicus and X. granatum had significantly decreased survival (X 48 and 70%) and growth in height (X 61 and 96%) and biomass (X 66 and 85%). Bruguiera parviflora showed decreased survival (X 59%), but there was no effect of insects on the growth of surviving propagules. In contrast, there was no effect of insect damage on the survival of seedlings of Avicennia marina and Bruguiera exaristata, but decreased growth in height (X 22 and 25%) and biomass (X 22 and 26%). Survival and growth of seedlings of Rhizophora stylosa and Bruguiera gymnorrhiza were not affected. The influence of insect seed predators on the survival and growth of seeds of mangrove species in forests will depend on the relative abundance of seed-eating crabs and intertidal position in mangrove forests. PMID:22160114

  7. [Structure and dynamics of the mangrove forest in the Rancheria River delta, Colombian Caribbean].

    PubMed

    Lema Vélez, Luisa Fernanda; Polanía, Jaime

    2007-03-01

    We registered seedling survival and biomass increase for Rhizophora mangle L., Avicennia germinans L. and Laguncularia racemosa (L.) Gaertn. f, main mangrove species in the Rancheria River delta, Colombia. Only seedlings of R. mangle were found to survive. We also measured maximum rate of litterfall. We estimated annual litterfall through interpolation within an exponential regression performed with maximum and annual litterfall data published in other sources; the value of annual litterfall for the area was estimated to be 12.9 mgha(-1)y(-1). We found a 7.4 mgha(-1)y(-1)(-1) increase in biomass. Litterfall constitutes the larger fraction of the 20.2 mgha(-1)y(-1) productivity of this mangrove. We believe this is a very high value for a forest under unfavorable natural and human conditions, such as high seasonality and continuous use of the forest to feed goats and sheep. We consider that the high productivity is a response to both natural and anthropogenic stress. PMID:18457110

  8. Mapping mangrove leaf area index at the species level using IKONOS and LAI-2000 sensors for the Agua Brava Lagoon, Mexican Pacific

    NASA Astrophysics Data System (ADS)

    Kovacs, John M.; Wang, Jinfei; Flores-Verdugo, Francisco

    2005-01-01

    Using both IKONOS and in situ LAI-2000 sensor data, a map of estimated LAI, based on NDVI, was created for the Agua Brava Lagoon, Mexican Pacific. The LAI values were then aggregated according to four classes; red mangrove ( Rhizophora mangle), healthy white mangrove ( Laguncularia racemosa), poor condition white mangrove and dead mangrove. Of the live mangrove, calculated at approximately 85% of the forest, mean LAI values of 2.49, 1.74 and 0.85 were determined for the red, healthy white and poor condition white mangrove, respectively. Excluding the dead areas, an overall estimated mangrove LAI value of 1.81 was ascertained for the 71 km 2 of mapped mangrove forest. Although the results do suggest the technique as a very rapid and effective method for monitoring the condition of mangroves at the species level, potential limitations are also discussed.

  9. Climate change influence on organic carbon remobilization, transport and burial in mangrove forests of Everglades National Park, USA

    NASA Astrophysics Data System (ADS)

    Smoak, J. M.; Breithaupt, J.; Smith, T. J.; Sanders, C. J.

    2013-05-01

    Mangrove ecosystems store large quantities of organic carbon (OC), burying it in their soils at a greater rate than terrestrial forests, thus providing an important negative climate change feedback. However, mangrove ecosystem response to climate change-induced stressors will determine if mangrove ecosystems continue to be a sink for OC. The threats of rising sea level outpacing mangrove forest soil accretion and the increased wave energy associated with this rise are two potential climate change stressors that may alter the carbon balance in mangrove ecosystems. The threat from wave energy is amplified during storm events, which may become more intense and/or frequent with climate change. Climate change-amplified storms could increasingly damage mangrove forests along the coastline, remobilizing and exposing previously buried OC to oxidation, and contribute to increasing atmospheric CO2 concentrations. We investigate the fate of this remobilized OC by examining soil cores from two sites within Everglades National Park. Soil accretion rates and OC burial rates within a storm surge deposit are compared to long-term rates (i.e., last 100 years). The sites are 4 and 10 km inland from the coast and data show these mangrove soils are accreting at a rate sufficient to keep pace with the current rate of sea-level rise. The accretion rates range from 2.5 to 3.6 mm yr-1 and are much greater within the storm surge deposit, reaching as high as 6.5 mm yr-1. We also discovered enhanced rates of OC burial within this same storm surge deposit which are approximately 2-fold greater than the long-term rates. Our findings indicate that these enhanced accretion and OC burial rates are due to inland transport of marine carbonate material and OC remobilized from along the coast during the storm. Furthermore, we find OC burial rates within the storm deposit at the site 10 km inland are substantially greater than the site 4 km inland, while mass accumulation rates show the opposite trend

  10. Degradation of medium-chain-length polyhydroxyalkanoates in tropical forest and mangrove soils.

    PubMed

    Lim, Siew-Ping; Gan, Seng-Neon; Tan, Irene K P

    2005-07-01

    Bacterial polyhydroxyalkanoates (PHAs) are perceived to be a suitable alternative to petrochemical plastics because they have similar material properties, are environmentally degradable, and are produced from renewable resources. In this study, the in situ degradation of medium-chain-length PHA (PHAMCL) films in tropical forest and mangrove soils was assessed. The PHAMCL was produced by Pseudomonas putida PGA1 using saponified palm kernel oil (SPKO) as the carbon source. After 112 d of burial, there was 16.7% reduction in gross weight of the films buried in acidic forest soil (FS), 3.0% in the ones buried in alkaline forest soil by the side of a stream (FSst) and 4.5% in those buried in mangrove soil (MS). There was a slight decrease in molecular weight for the films buried in FS but not for the films buried in FSst and in MS. However, no changes were observed for the melting temperature, glass transition temperature, monomer compositions, structure, and functional group analyses of the films from any of the burial sites during the test period. This means that the integral properties of the films were maintained during that period and degradation was by surface erosion. Scanning electron microscopy of the films from the three sites revealed holes on the film surfaces which could be attributed to attack by microorganisms and bigger organisms such as detritivores. For comparison purposes, films of polyhydroxybutyrate (PHB), a short-chain-length PHA, and polyethylene (PE) were buried together with the PHAMCL films in all three sites. The PHB films disintegrated completely in MS and lost 73.5% of their initial weight in FSst, but only 4.6% in FS suggesting that water movement played a major role in breaking up the brittle PHB films. The PE films did not register any weight loss in any of the test sites. PMID:16014996

  11. An Evaluation of the MOD17 Gross Primary Production Algorithm in a Mangrove Forest

    NASA Astrophysics Data System (ADS)

    Wells, H.; Najjar, R.; Herrmann, M.; Fuentes, J. D.; Ruiz-Plancarte, J.

    2015-12-01

    Though coastal wetlands occupy a small fraction of the Earth's surface, they are extremely active ecosystems and play a significant role in the global carbon budget. However, coastal wetlands are still poorly understood, especially when compared to open-ocean and terrestrial ecosystems. This is partly due to the limited in situ observations in these areas. One of the ways around the limited in situ data is to use remote sensing products. Here we present the first evaluation of the MOD17 remote sensing algorithm of gross primary productivity (GPP) in a mangrove forest using data from a flux tower in the Florida Everglades. MOD17 utilizes remote sensing products from the Moderate Resolution Imaging Spectroradiometer and meteorological fields from the NCEP/DOE Reanalysis 2. MOD17 is found to capture the long-term mean and seasonal amplitude of GPP but has significant errors describing the interannual variability, intramonthly variability, and the phasing of the annual cycle in GPP. Regarding the latter, MOD17 overestimates GPP when salinity is high and underestimates it when it is low, consistent with the fact that MOD17 ignores salinity and salinity tends to decrease GPP. Including salinity in the algorithm would then most likely improve its accuracy. MOD17 also assumes that GPP is linear with respect to PAR (photosynthetically active radiation), which does not hold true in the mangroves. Finally, the estimated PAR and air temperature inputs to MOD17 were found to be significantly lower than observed. In summary, while MOD17 captures some aspects of GPP variability at this mangrove site, it appears to be doing so for the wrong reasons.

  12. Influence of Sea-Level Rise and Storms on Soil Accretion Rates in the Mangrove Forests of Everglades National Park, USA

    NASA Astrophysics Data System (ADS)

    Smoak, J. M.; Breithaupt, J.; Smith, T., III; Sanders, C. J.; Peterson, L. C.

    2014-12-01

    Mangrove forests provide a range of valuable ecosystem services including sequestering large quantities of organic carbon (OC) in their soils at rates higher than other forests. Whether or not mangrove soils continue to be a sink for OC will be determined by the mangrove ecosystems' response to climate change-induced stressors. The threats of rising sea level outpacing mangrove forest soil accretion and increased wave energy associated with this rise may become the primary climate change-induced stressors on mangrove ecosystems. The threat from wave energy is amplified during storm events, which could increasingly damage mangrove forests along the coastline. However, storms may enhance accretion rates at some sites due to delivery of storm surge material, which could increase the system's ability to keep pace with sea-level rise (SLR). To investigate these processes we measure soil accretion rates over the last 100 years (via 210Pb dating) within the mangrove forests of Everglades National Park, which are situated within the largest contiguous mangrove forest in North America. Accretion rates range from 2 to 2.8 mm per year for sites within 10 km of the Gulf of Mexico. These rates match (within error) or exceed SLR over the last 100 years. Sites farther inland than 10 km have slightly lower accretion rates. Throughout the system organic matter accumulation is the most important source material contributing to accretion. The more seaward sites also show an important contribution from carbonate material. Soil cores from the most seaward sites exhibited visual laminations and Ca peaks (determined via x-ray fluorescence). These are indicators of storm surge deposits. While higher sea level might produce more damage and loss of mangrove forest along open water (e.g., Gulf of Mexico), our findings suggest some sites will have enhanced accretion rates due to supplementation with storm surge material.

  13. Rapid seawater circulation through animal burrows in mangrove forests - A significant source of saline groundwater to the tropical coastal ocean

    NASA Astrophysics Data System (ADS)

    Clark, J. F.; Stieglitz, T. C.; Hancock, G. J.

    2010-12-01

    A common approach for quantifying rates of submarine groundwater discharge (SGD) to the coastal ocean is to use geochemical tracers that are part of the U- and Th-decay chains such as Rn-222 and short lived radium isotopes. These radionuclides are naturally enriched in groundwater relative to seawater and have well understood chemistries within the marine environment. They occur in both fresh (continental) and saline (marine) groundwaters and thus the water source is often ambiguous. Stieglitz (2005, Marine Pollution Bulletin 51, 51-59) has shown that some coastal areas within the Great Barrier Reef (GBR) lagoon (Australia) are enriched in the SGD tracer, Rn-222; he attributed this to four possible processes including the tidal flushing of mangrove forest floors. Here, we present a detailed investigation into the tidal circulation of seawater through animal burrows using Rn-222 and isotopes of radium in the Coral Creek mangrove forest, Hinchinbrook Island, Queensland, Australia. The study was conducted at the end of the dry season in a creek with no freshwater inputs. Significant export of radionuclides and salt from the forest into the creek indicates continuous tidally driven circulation through the burrows. Results demonstrate that the forest sediment is efficiently flushed, with a water flux of about 30 L/m2/ day of forest floor, which is equivalent to flushing about 10% of the total burrow volume per tidal cycle. Annual average circulation flux through mangrove forest floors are of the same order as annual river discharge in the central GBR. However, unlike the river discharge, the tidal circulation should be relatively stable throughout the year. This work documents the importance of animal burrows in maintaining productive sediments in these systems, and illustrates the physical process that supports large exports of organic and inorganic matter from mangrove forests to the coastal zone. It also illustrates the importance of considering saline groundwater

  14. Nutrition of mangroves.

    PubMed

    Reef, Ruth; Feller, Ilka C; Lovelock, Catherine E

    2010-09-01

    Mangrove forests dominate the world's tropical and subtropical coastlines. Similar to other plant communities, nutrient availability is one of the major factors influencing mangrove forest structure and productivity. Many mangrove soils have extremely low nutrient availability, although nutrient availability can vary greatly among and within mangrove forests. Nutrient-conserving processes in mangroves are well developed and include evergreeness, resorption of nutrients prior to leaf fall, the immobilization of nutrients in leaf litter during decomposition, high root/shoot ratios and the repeated use of old root channels. Both nitrogen-use efficiency and nutrient resorption efficiencies in mangroves are amongst the highest recorded for angiosperms. A complex range of interacting abiotic and biotic factors controls the availability of nutrients to mangrove trees, and mangroves are characteristically plastic in their ability to opportunistically utilize nutrients when these become available. Nitrogen and phosphorus have been implicated as the nutrients most likely to limit growth in mangroves. Ammonium is the primary form of nitrogen in mangrove soils, in part as a result of anoxic soil conditions, and tree growth is supported mainly by ammonium uptake. Nutrient enrichment is a major threat to marine ecosystems. Although mangroves have been proposed to protect the marine environment from land-derived nutrient pollution, nutrient enrichment can have negative consequences for mangrove forests and their capacity for retention of nutrients may be limited.

  15. Heavy metal contamination and ecological risk in Futian mangrove forest sediment in Shenzhen Bay, South China.

    PubMed

    Li, Rongyu; Li, Ruili; Chai, Minwei; Shen, Xiaoxue; Xu, Hualin; Qiu, Guoyu

    2015-12-15

    Surface sediments in the Futian mangrove forest (South China) were analyzed for heavy metals including cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn). The heavy metal distributions varied greatly in surface sediments, reflecting some sediment heterogeneity. The heavy metal concentrations decreased in the order of Zn>Cr>Pb>Cu>Cd. According to the mean probable effects level quotient, the combination of studied metals had a 21% probability of being toxic. The potential ecological risk index and geo-accumulation index also revealed high metal contamination. Cd was of primary concern due to its higher assessment values and potential for adverse biological effects. Multivariate analysis implied that clay and silt played a significant role in raising the levels of Cr, Cu and Zn. The percentage of mobile heavy metals was relatively higher, without considerable ecological risk to the biota based on the risk assessment code. PMID:26478455

  16. Heavy metal contamination and ecological risk in Futian mangrove forest sediment in Shenzhen Bay, South China.

    PubMed

    Li, Rongyu; Li, Ruili; Chai, Minwei; Shen, Xiaoxue; Xu, Hualin; Qiu, Guoyu

    2015-12-15

    Surface sediments in the Futian mangrove forest (South China) were analyzed for heavy metals including cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn). The heavy metal distributions varied greatly in surface sediments, reflecting some sediment heterogeneity. The heavy metal concentrations decreased in the order of Zn>Cr>Pb>Cu>Cd. According to the mean probable effects level quotient, the combination of studied metals had a 21% probability of being toxic. The potential ecological risk index and geo-accumulation index also revealed high metal contamination. Cd was of primary concern due to its higher assessment values and potential for adverse biological effects. Multivariate analysis implied that clay and silt played a significant role in raising the levels of Cr, Cu and Zn. The percentage of mobile heavy metals was relatively higher, without considerable ecological risk to the biota based on the risk assessment code.

  17. Mangrove Plantation Forest Assessment Using Structural Attributes Derived from Light Detection and Ranging (LiDAR) Data

    NASA Astrophysics Data System (ADS)

    Faelga, R. A. G.; Paringit, E. C.; Perez, G. J. P.; Ibanez, C. A. G.; Argamosa, R. A. L.; Posilero, M. A. V.; Zaragosa, G. P.; Tandoc, F. A. M.; Malabanan, M. V.

    2016-06-01

    Estimating the structural and functional attributes of forests is integral in performing management strategies and for understanding forest ecosystem functions. Field sampling methods through plot level is one of the known strategies in forest studies; however, these methods have its limitations and are prone to subjected biases. Remote Sensing data, particularly that of Light Detection and Ranging (LiDAR) can be utilized to alleviate the limitations of extracting forest structure parameters. The study aims to characterize a Rhizophoraceae-dominated mangrove forest plantation. Point cloud distribution within a 1-hectare plot was processed by utilizing thirty (30) samples of 5x5 meter plots, which were analysed for the characterization and forest structure assessment. Point densities were grouped at intervals of 10% of the plot's maximum height (Height at Bincentile or HBn) to determine where the clustering of points occur per plot. The result shows that most of the points are clustered at HBn with height values ranging from 2.98 to 4.15 meters for plots located at the middle part of the forest, with a standard deviation of 1.78 to 3.69, respectively. On the other hand, sample plots that are located at the periphery part of the forest shows that the point clustering occurs at different heights ranging from 1.71 meters to 4.43 meters, with standard deviation values ranging from 1.69 to 3.81.Plots that are located along the fringes of the forest reflect a stunted clustering of points, while plots that explicitly show mangrove trimmings and cuts reflect even distribution in terms of point density within each HBn. Both species present in the area (R. mucronata and R. apiculata) exhibits similar clustering, which could represent detection of Rhizophoraceae mangroves.

  18. Monitoring hydrogeochemical interactions in coastal mangroves in Everglades National Park using field spectroscopy and remote sensing

    NASA Astrophysics Data System (ADS)

    Lagomasino, D.; Price, R. M.; Campbell, P. K.

    2011-12-01

    Coastal tropical and subtropical environments, where there are distinct seasonal shifts in precipitation, can be highly susceptible to environmental changes caused by increasing anthropogenic pressure (e.g., urbanization, deforestation) in addition to natural "press and pulse" events, such as sea-level rise, tropical storms, and a changing climate. These man-made and natural perturbations directly affect the quality and quantity of water flowing through the ecosystem, both on the surface and subsurface. Changes in groundwater and surface water interactions will impact ecological communities, including highly vulnerable coastal mangrove communities. Nearly 1,445 km2 of mangroves cover Everglades National Park along the southern and southwestern coast of Florida. Rising sea levels, a predicted drier climate, and increased water demand may accelerate the landward migration of salt water intrusion which poses threats to the ecological communities along this coastal ecotone. This is a growing concern for the region and it is necessary that we understand the present hydrogeologic conditions to better monitor and model the future and inevitable changes to the coastal environment. The purpose of this preliminary study was to test the feasibility of measuring water quality indirectly from the spectral responses of mangrove vegetation on a regional scale. Spectra-derived biophysical indices were used to assess various relationships between the spectral signatures of the 3 main mangrove species (i.e., Avicennia germinans, Rhizophora mangle, and Laguncularia racemosa) and the ionic and nutrient concentrations in the porewater (i.e., 20cm and 100cm depths), surface water, and groundwater of the mangrove ecotone. Water samples from these sources were collected during the dry season, a transitional period, and the wet season at three sites in large, high-biomass mangroves along Shark River and two sites in dwarf, low-biomass, mangroves along Taylor River. Water samples were

  19. Litter processing and population food intake of the mangrove crab Ucides cordatus in a high intertidal forest in northern Brazil

    NASA Astrophysics Data System (ADS)

    Nordhaus, Inga; Wolff, Matthias; Diele, Karen

    2006-03-01

    This study provides the first quantification of the population food intake of the litter-consuming mangrove crab Ucides cordatus (Ocypodidae, L. 1763) in a New World mangrove forest. Diet, feeding periodicity, gastric evacuation rates and size-dependent consumption were determined for this intensively exploited semi-terrestrial crab in different types of mangrove forest. Unlike many other crabs Ucides cordatus is a continuous feeder, as shown by gastrointestinal contents over a day's cycle. Starvation experiments revealed that most gastric evacuation occurs during the first 12 h after feeding, following an exponential decay function. Evacuation rates (0.35 h -1 and 0.31 h -1) for small (carapace width CW 2.5-3.5 cm) and large (CW 6.5-7.5 cm) crabs, respectively, and the mean daily gastrointestinal contents were used to calculate the daily food intake (DFI) of U. cordatus for both sexes and different size classes. DFI was strongly correlated to body size and ranged from 19.8 to 6.0% of body dry weight in small and large crabs, respectively. The daily energy intake of U. cordatus (37.6 kJ for a 65 g wet weight specimen) was high when compared to other leaf-eating crabs. Litter fall and propagule production were calculated as 16.38 t ha -1 y -1, corresponding to a daily mean of 4.49 g m -2 in a high intertidal Rhizophora mangle forest stand. The estimated population food intake of Ucides cordatus (4.1 g dw m -2 d -1) corresponds to 81.3% of this production. This high litter removal rate, a low litter quantity in burrows and high consumption rates during field experiments suggest that the local crab population is food-limited in many parts of the study area. The very efficient coupling of forest litter production and crab litter consumption is possible due to the high crab density and the low inundation frequency of the mangrove forests, allowing for prolonged foraging periods. By processing the major part of the litter, U. cordatus helps to retain nutrients and energy

  20. The increased concentration of SO{sub 2} and threat to the largest mangrove forest of the world - the Sundarbans

    SciTech Connect

    Ahmad, J.U.; Ullah, S.S.; Carmichael, G.R.; Haque, R.

    1996-12-31

    The atmospheric concentration of SO{sub 2} was monitored in two different sites, Khulna and Savar in Bangladesh as a part of Rains Asia Atmos Module, Phase I Project. The results show that the winter concentration of SO{sub 2} in Khulna is 3 to 4 times higher than the summer concentrations, which is also higher compared to measurements at Savar which is adjacent to Dhaka city. Based on these facts and seasonal wind pattern, trans-boundary air pollution has been suggested. Khulna is in the southwestern part of Bangladesh and this area harbors the largest mangrove forest of the world, the Sundarbans. Sundari trees are the main trees of the Sundarban ecosystem. During the last few years, many of the Sundari trees, which are quite susceptible to pH stress, are dying from the top. The unusual winter increase of atmospheric sulphurdioxide has been assigned to be one of the reasons for the top dying. Other factors might be the increase of salinity and diminished flow of water.

  1. Landscape-scale extent, height, biomass, and carbon estimation of Mozambique's mangrove forests with Landsat ETM+ and Shuttle Radar Topography Mission elevation data

    NASA Astrophysics Data System (ADS)

    Fatoyinbo, Temilola E.; Simard, Marc; Washington-Allen, Robert A.; Shugart, Herman H.

    2008-06-01

    Mangroves are salt tolerant plants that grow within the intertidal zone along tropical and subtropical coasts. They are important barriers for mitigating coastal disturbances, provide habitat for over 1300 animal species and are one of the most productive ecosystems. Mozambique's mangroves extend along 2700 km and cover one of the largest areas in Africa. The purpose of this study was to determine the countrywide mean tree height spatial distribution and biomass of Mozambique's mangrove forests using Landsat ETM+ and Shuttle Radar Topography Mission (SRTM) data. The SRTM data were calibrated using the Landsat derived land-cover map and height calibration equations. Stand-specific canopy height-biomass allometric equations developed from field measurements and published height-biomass equations were used to calculate aboveground biomass of the mangrove forests on a landscape scale. The results showed that mangrove forests covered a total of 2909 km2 in Mozambique, a 27% smaller area than previously estimated. The SRTM calibration indicated that average tree heights changed with geographical settings. Even though the coast of Mozambique spans across 16 degrees latitude, we did not find a relationship between latitude and biomass. These results confirm that geological setting has a greater influence than latitude alone on mangrove production. The total mangrove dry aboveground biomass in Mozambique was 23.6 million tons and the total carbon was 11.8 million tons.

  2. Emersion in the mangrove forest fish Rivulus marmoratus: A unique response to hydrogen sulfide

    SciTech Connect

    Abel, D.C.; Koenig, C.C.; Davis, W.P.

    1987-01-01

    The mangrove forest fish Rivulus marmoratus (Cyprinodontidae) has frequently been observed out of water, a phenomenon generally attributed to habitat drying. The hypothesis that hydrogen sulfide, a substance characteristically found in their environment, can serve as a stimulus for emersion, is tested in this study. In the field R. marmoratus was found in water with low to moderate level of H{sub 2}S. In the laboratory, R marmora leaped from water contaminated with H{sub 2}S at ecologically relevant concentrations. Aquatic hypoxia did not induce emersion, but prey capture did. Oxygen consumption by both juveniles and adults decreased significantly in air. These results suggest that avoidance of H{sub 2}S and the ability to survive terrestrial conditions enable this species to permanently occupy an area of the forest unavailable to other fishes. Furthermore, because a variety of stimuli lead to emersion in R. marmoratus, terrestriality in this species is likely a generalized response to environmental stress as well as a means of exploiting terrestrial resources. 16 refs., 1 fig., 2 tabs.

  3. Interspecific variation of the bacterial community structure in the phyllosphere of the three major plant components of mangrove forests

    PubMed Central

    Dias, Armando Cavalcante Franco; Taketani, Rodrigo Gouveia; Andreote, Fernando Dini; Luvizotto, Danice Mazzer; da Silva, João Luis; Nascimento, Rosely dos Santos; de Melo, Itamar Soares

    2012-01-01

    Mangrove forests encompass a group of trees species that inhabit the intertidal zones, where soil is characterized by the high salinity and low availability of oxygen. The phyllosphere of these trees represent the habitat provided on the aboveground parts of plants, supporting in a global scale, a large and complex microbial community. The structure of phyllosphere communities reflects immigration, survival and growth of microbial colonizers, which is influenced by numerous environmental factors in addition to leaf physical and chemical properties. Here, a combination of culture-base methods with PCR-DGGE was applied to test whether local or plant specific factors shape the bacterial community of the phyllosphere from three plant species (Avicenia shaueriana, Laguncularia racemosa and Rhizophora mangle), found in two mangroves. The number of bacteria in the phyllosphere of these plants varied between 3.62 x 104 in A. schaeriana and 6.26 x 103 in R. mangle. The results obtained by PCR-DGGE and isolation approaches were congruent and demonstrated that each plant species harbor specific bacterial communities in their leaves surfaces. Moreover, the ordination of environmental factors (mangrove and plant species), by redundancy analysis (RDA), also indicated that the selection exerted by plant species is higher than mangrove location on bacterial communities at phyllosphere. PMID:24031877

  4. Interspecific variation of the bacterial community structure in the phyllosphere of the three major plant components of mangrove forests.

    PubMed

    Dias, Armando Cavalcante Franco; Taketani, Rodrigo Gouveia; Andreote, Fernando Dini; Luvizotto, Danice Mazzer; da Silva, João Luis; Nascimento, Rosely Dos Santos; de Melo, Itamar Soares

    2012-04-01

    Mangrove forests encompass a group of trees species that inhabit the intertidal zones, where soil is characterized by the high salinity and low availability of oxygen. The phyllosphere of these trees represent the habitat provided on the aboveground parts of plants, supporting in a global scale, a large and complex microbial community. The structure of phyllosphere communities reflects immigration, survival and growth of microbial colonizers, which is influenced by numerous environmental factors in addition to leaf physical and chemical properties. Here, a combination of culture-base methods with PCR-DGGE was applied to test whether local or plant specific factors shape the bacterial community of the phyllosphere from three plant species (Avicenia shaueriana, Laguncularia racemosa and Rhizophora mangle), found in two mangroves. The number of bacteria in the phyllosphere of these plants varied between 3.62 x 10(4) in A. schaeriana and 6.26 x 10(3) in R. mangle. The results obtained by PCR-DGGE and isolation approaches were congruent and demonstrated that each plant species harbor specific bacterial communities in their leaves surfaces. Moreover, the ordination of environmental factors (mangrove and plant species), by redundancy analysis (RDA), also indicated that the selection exerted by plant species is higher than mangrove location on bacterial communities at phyllosphere. PMID:24031877

  5. Forest health monitoring: Field methods guide

    SciTech Connect

    Tallent-Halsell, N.G.

    1994-10-01

    This guide is intended to instruct Forest Health Monitors when collecting data on forest health indicators; site condition, growth and regeneration, crown condition, tree damage and mortality assessment, photosynthetically active radiation, vegetation structure, ozone bioindicator species, lichen community structure and field logistics. This guide contains information on measuring, observing and recording data related to the above listed forest health indicators. Pertinent quality assurance information is also included.

  6. Forest structure and litter production of naturally re-generated white mangrove Avicennia marina in sub-tropical estuarine coast.

    PubMed

    Abu Hena, M K; Sidik, B Japar; Idris, M H; Nesarul, M H; Aysha, A; Islam, M S; Nazmul, H

    2015-09-01

    The present work deals with plant structure, phenology, litter production and decomposition of mangrove Avicennia marina in the newly re-generated mangrove forest in sub-tropical coast. The natural generation in this accreted coastal land of mono-specific A. marina forest stand was prominent, with 45% seedlings and 32% saplings. Peak flowering and fruiting were noticed in May and August, respectively. Reproductive components contribute countable percent into the total litter production during the peak flowering (60%) and fruiting (86%) season. The percentage of leaf litter fall fluctuated throughout the year and contributed 13-99% (73% in average) of the total litter production of 11.53 tones ha(-1)'yr(-1). The total litter production differed with season and influenced by local climate, pore water salinity and phenology of the mangrove. The naturally generated young (7 years) A. marina with 1.8 m height produced more leaf litter as compared to similar tree height elsewhere. Decomposition rate was related to season, with higher litter loss during rainy season which could help cycling nutrients and support estuarine food web by supplying organic matter into the sub-tropical coastal environment. PMID:26521566

  7. Typhoons exert significant but differential impacts on net ecosystem carbon exchange of subtropical mangrove forests in China

    NASA Astrophysics Data System (ADS)

    Chen, H.; Lu, W.; Yan, G.; Yang, S.; Lin, G.

    2014-10-01

    Typhoons are very unpredictable natural disturbances to subtropical mangrove forests in Asian countries, but little information is available on how these disturbances affect ecosystem level carbon dioxide (CO2) exchange of mangrove wetlands. In this study, we examined short-term effect of frequent strong typhoons on defoliation and net ecosystem CO2 exchange (NEE) of subtropical mangroves, and also synthesized 19 typhoons during a 4-year period between 2009 and 2012 to further investigate the regulation mechanisms of typhoons on ecosystem carbon and water fluxes following typhoon disturbances. Strong wind and intensive rainfall caused defoliation and local cooling effect during the typhoon season. Daily total NEE values decreased by 26-50% following some typhoons (e.g., W28-Nockten, W35-Molave and W35-Lio-Fan), but significantly increased (43-131%) following typhoon W23-Babj and W38-Megi. The magnitudes and trends of daily NEE responses were highly variable following different typhoons, which were determined by the balance between the variances of gross ecosystem production (GEP) and ecosystem respiration (RE). Furthermore, results from our synthesis indicated that the landfall time of typhoon, wind speed and rainfall were the most important factors controlling the CO2 fluxes following typhoon events. These findings indicate that different types of typhoon disturbances can exert very different effects on CO2 fluxes of mangrove ecosystems and that typhoon will likely have larger impacts on carbon cycle processes in subtropical mangrove ecosystems as the intensity and frequency of typhoons are predicted to increase under future global climate change scenarios.

  8. Characterization of mangrove species using ALOS-2 PALSAR in Hai Phong city, Vietnam

    NASA Astrophysics Data System (ADS)

    Dat Pham, Tien; Yoshino, Kunihiko

    2016-06-01

    Hai Phong city is located in the Northern coast of Vietnam where the mangroves are distributed between zone I and zone II among the four mangrove zones in Vietnam. This city is vulnerable to rising sea levels associated with climate change and tropical cyclones, which are forecasted to become more severe due to the impact of climate change. In the past, mangrove forests in this city have decreased markedly because of over expansion of shrimp farming. Thus, identification of mangrove forests is important to monitor and support mangrove conservation and management in the coastal zone. The objectives of this research were to identify the locations of mangrove and characterize mangrove species in Hai Phong using HH and HV backscatters of the Advanced Land Observing Satellite 2 (ALOS-2) with enhanced Phased Array L-band Synthetic Aperture Radar (PALSAR). Image segmentation was used to identify the locations of mangrove forests. Moreover, Geographic Information System (GIS) was applied to update current status of mangrove species in 2015. The results showed that the means of HH and HV backscatter coefficients of K. obovata are lower than S. caseolaris. K. obovata has HH value around -13.9 dB until -10.3 dB and HV value around -20.6 dB until -16.2 dB. Higher HH values between about -14.9 dB and -6.8 dB and HV values between roughly -20.6 dB and -14.3 dB have observed by S. caseolaris. The total area of mangrove forest in Hai Phong in the year 2015 was around 4084 hectares, of which S. caseolaris occupied over 68% and mixed mangrove species was approximately 25.6%. This research indicates the potential for the use of L-band ALOS-2 PALSAR in characterizing mangrove forest species in the coastal zone.

  9. Anoxic Decomposition in Sediments from a Tropical Mangrove Forest and the Temperate Wadden Sea: Implications of N and P Addition Experiments

    NASA Astrophysics Data System (ADS)

    Holmboe, N.; Kristensen, E.; Andersen, F. Ø.

    2001-08-01

    The anoxic decomposition processes in sediments from a tropical mangrove forest (Bangrong, Thailand) and a salt marsh in the temperate Wadden Sea (Denmark) were compared, and the effects of increased ammonium and/or phosphate concentrations on the anoxic decomposition were studied. Sediment was incubated in jars (20-ml glass vials) and changes in porewater solutes were followed in a time series of 3 weeks. Furthermore, the short-term fate (days) of dissolved inorganic phosphate (DIP) added to Bangrong mangrove sediment was evaluated from phosphorus fractionation. Although the organic matter at both study sites had relatively high C:N and C:P ratios, the anoxic sediment decomposition was not affected by nutrient enrichments at the level applied in this study. The sediment metabolism (TCO 2and DOC production, and sulfate consumption) was 5-10 times higher in Wadden Sea sediment than in Bangrong mangrove sediment, probably due to the higher content of structural carbohydrates (e.g. cellulose) as indicated by higher C:N and C:P ratios in mangrove organic matter. This is substantiated by a lower nutrient release from Bangrong mangrove sediments and suggests a faster turnover of N and P by nutrient deficient bacteria in the mangrove sediment. DIP was released during anoxic decomposition in Wadden Sea sediment, but was retained in Bangrong mangrove sediment. Analysis of phosphorus fractions in Bangrong mangrove sediment revealed that added excess DIP was efficiently taken up by the sediment particles and primarily retrieved in the easily exchangeable and iron bound fractions. The studied mangrove forest sediment seems to be a phosphorus sink.

  10. Leaf removal by sesarmid crabs in Bangrong mangrove forest, Phuket, Thailand; with emphasis on the feeding ecology of Neoepisesarma versicolor

    NASA Astrophysics Data System (ADS)

    Thongtham, Nalinee; Kristensen, Erik; Puangprasan, Som-Ying

    2008-12-01

    Field measurements on leaf removal by populations of sesarmid crabs at different locations in the Bangrong mangrove forest, Phuket, Thailand, indicated that crabs on average can remove 87% of the daily leaf litter fall by ingestion or burial. The removal rate is correlated positively with the number of crab burrows and negatively with tidal inundation time. The results from the field were supplemented with observations on the behavior of Neoepisesarma versicolor in laboratory microcosms and a mangrove mesocosm. N. versicolor feeds primarily at night and total time spent feeding was up to an order of magnitude higher in the artificial microcosms than under simulated in situ conditions in the mesocosm. Most of the time during both day and night was spent resting near the entrance or inside burrows. N. versicolor mainly feeds on mangrove leaves and scraps of food material from the sediment surface. This is supported by examinations of stomach content, which showed that 62% is composed of higher plant material and 38% of detritus and mineral particles from the sediment. The nutritive value of leaves and detritus is insufficient to maintain crab growth. Sesarmid crabs may instead obtain the needed nutrients by occasional consumption of nitrogen-rich animal tissues, such as carcasses of fish and crustaceans, as indicated by the presence of animal remains in the stomach and the willingness of crabs to consume fish meat. Laboratory experiments on leaf consumption and leaf preferences of N. versicolor indicate that they preferentially feed on brown leaves, if available, followed by green and yellow leaves. If all species of sesarmid crabs in the Bangrong mangrove forest consume leaves at the same rate as N. versicolor, they could potentially ingest 52% of the total litter fall.

  11. Regeneration of Rhizophora mangle in a Caribbean mangrove forest: interacting effects of canopy disturbance and a stem-boring beetle.

    PubMed

    Sousa, Wayne P; Quek, Swee P; Mitchell, Betsy J

    2003-11-01

    Current theory predicts that in low-density, seed-limited plant populations, seed predation will be more important than competition in determining the number of individuals that reach maturity. However, when plant density is high, competition for microsites suitable for establishment and growth is expected to have a relatively greater effect. This dichotomous perspective does not account for situations in which the risk of seed predation differs inside versus outside recruitment microsites. We report the results of a field experiment and sampling studies that demonstrate such an interaction between microsite quality and the risk of propagule predation in mangrove forests on the Caribbean coast of Panama, where it appears to play a key role in shaping the demography and dynamics of the mangrove, Rhizophora mangle. Rhizophora's water-borne propagules establish wherever they strand, but long-term sampling revealed that only those that do so in or near lightning-created canopy gaps survive and grow to maturity. These microsites afford better growth conditions than the surrounding understory and, as importantly, provide a refuge from predation by the scolytid beetle, Coccotrypes rhizophorae. This refuge effect was confirmed with a field experiment in which Rhizophora seedlings were planted at different positions relative to gap edges, from 5 m inside to 20 m outside the gap. Mortality due to beetle attack increased linearly from an average of 10% inside a gap to 72% at 20 m into the forest. The interaction between canopy disturbance and propagule predation may be having a large impact on the composition of our study forests. Being shade-tolerant, Rhizophora seedlings that escape or survive beetle attack can persist in the understory for years. However, the high rate of beetle-induced mortality effectively eliminates the contribution of advance regeneration by Rhizophora saplings to gap succession. This may explain why the shade-intolerant mangrove, Laguncularia racemosa

  12. Meiofauna distribution in a mangrove forest exposed to shrimp farm effluents (New Caledonia).

    PubMed

    Della Patrona, L; Marchand, C; Hubas, C; Molnar, N; Deborde, J; Meziane, T

    2016-08-01

    Meiofauna abundance, biomass and individual size were studied in mangrove sediments subjected to shrimp farm effluents in New Caledonia. Two strategies were developed: i) meiofauna examination during the active (AP) and the non-active (NAP) periods of the farm in five mangrove stands characteristics of the mangrove zonation along this coastline, ii) meiofauna examination every two months during one year in the stand the closest to the pond (i.e. Avicennia marina). Thirteen taxonomic groups of meiofauna were identified, with nematodes and copepods being the most abundant ones. Meiofauna abundance and biomass increased from the land side to the sea side of the mangrove probably as a result of the increased length of tidal immersion. Abundance of total meiofauna was not significantly different before and after the rearing period. However, the effluent-receiving mangrove presented twice the meiofauna abundance and biomass than the control one. Among rare taxa, mites appeared extremely sensitive to this perturbation.

  13. Monitoring air pollution in the Bialowieza Forest

    NASA Astrophysics Data System (ADS)

    Malzahn, Elżbieta; Sondej, Izabela; Paluch, Rafał

    2016-04-01

    Air pollution, as sulfur dioxide(SO2) and nitrous oxides (NOx), affects forest health negatively and can initiate forest dieback. Long-term monitoring (since 1986) and analyses are conducted in the Bialowieza Forest due to the threat by abiotic, biotic and anthropogenic factors. This forest has a special and unique natural value, as confirmed by the various forms of protection of national and international rank. The main aim of monitoring is to determine the level and trends of deposition of air pollutants and their effects on selected forest stands and forest communities in the Bialowieza Forest. Concentration measurements of gaseous pollutants and the chemical composition of the precipitation are performed at seven points within the forest area (62 219 ha). Measurement gauges are measuring gaseous pollutants (SO2 and NOx) by the passive method and collecting precipitation at each point at a height of three meters. The period of measuring by the instruments is 30 days. All analyses are conducted according to the methodology of the European forest monitoring program in the certified Laboratory of Natural Environment Chemistry of the Polish Forest Research Institute (IBL). The concentration of pollutant gases (dry deposition) in the years 2002-2015 accounted for only 6-13% of the limit in Poland, as defined by the Polish Ministry of Environment, and are of no threat to the forest environment. Wet deposition of pollutants, which dependents directly from the amount of precipitation and its concentration of pollutants, varied strongly between different months and years. Total deposition (dry and wet) of sulfur (S) and nitrogen (N) was calculated for seasonal and annual periods. On an annual basis, wet deposition represented approximately 80% of the total deposition of S and N. Total deposition of S did not exceed the average deposition values for forests in north-eastern Europe (5-10 kg ha‑1 year‑1) at any of the seven measuring points. Total deposition of N did

  14. Monitoring air pollution in the Bialowieza Forest

    NASA Astrophysics Data System (ADS)

    Malzahn, Elżbieta; Sondej, Izabela; Paluch, Rafał

    2016-04-01

    Air pollution, as sulfur dioxide(SO2) and nitrous oxides (NOx), affects forest health negatively and can initiate forest dieback. Long-term monitoring (since 1986) and analyses are conducted in the Bialowieza Forest due to the threat by abiotic, biotic and anthropogenic factors. This forest has a special and unique natural value, as confirmed by the various forms of protection of national and international rank. The main aim of monitoring is to determine the level and trends of deposition of air pollutants and their effects on selected forest stands and forest communities in the Bialowieza Forest. Concentration measurements of gaseous pollutants and the chemical composition of the precipitation are performed at seven points within the forest area (62 219 ha). Measurement gauges are measuring gaseous pollutants (SO2 and NOx) by the passive method and collecting precipitation at each point at a height of three meters. The period of measuring by the instruments is 30 days. All analyses are conducted according to the methodology of the European forest monitoring program in the certified Laboratory of Natural Environment Chemistry of the Polish Forest Research Institute (IBL). The concentration of pollutant gases (dry deposition) in the years 2002-2015 accounted for only 6-13% of the limit in Poland, as defined by the Polish Ministry of Environment, and are of no threat to the forest environment. Wet deposition of pollutants, which dependents directly from the amount of precipitation and its concentration of pollutants, varied strongly between different months and years. Total deposition (dry and wet) of sulfur (S) and nitrogen (N) was calculated for seasonal and annual periods. On an annual basis, wet deposition represented approximately 80% of the total deposition of S and N. Total deposition of S did not exceed the average deposition values for forests in north-eastern Europe (5-10 kg ha-1 year-1) at any of the seven measuring points. Total deposition of N did not

  15. National Satellite Forest Monitoring systems for REDD+

    NASA Astrophysics Data System (ADS)

    Jonckheere, I. G.

    2012-12-01

    Reducing Emissions from Deforestation and Forest Degradation (REDD) is an effort to create a financial value for the carbon stored in forests, offering incentives for developing countries to reduce emissions from forested lands and invest in low-carbon paths to sustainable development. "REDD+" goes beyond deforestation and forest degradation, and includes the role of conservation, sustainable management of forests and enhancement of forest carbon stocks. In the framework of getting countries ready for REDD+, the UN-REDD Programme assists developing countries to prepare and implement national REDD+ strategies. For the monitoring, reporting and verification, FAO supports the countries to develop national satellite forest monitoring systems that allow for credible measurement, reporting and verification (MRV) of REDD+ activities. These are among the most critical elements for the successful implementation of any REDD+ mechanism. The UN-REDD Programme through a joint effort of FAO and Brazil's National Space Agency, INPE, is supporting countries to develop cost- effective, robust and compatible national monitoring and MRV systems, providing tools, methodologies, training and knowledge sharing that help countries to strengthen their technical and institutional capacity for effective MRV systems. To develop strong nationally-owned forest monitoring systems, technical and institutional capacity building is key. The UN-REDD Programme, through FAO, has taken on intensive training together with INPE, and has provided technical help and assistance for in-country training and implementation for national satellite forest monitoring. The goal of the support to UN-REDD pilot countries in this capacity building effort is the training of technical forest people and IT persons from interested REDD+ countries, and to set- up the national satellite forest monitoring systems. The Brazilian forest monitoring system, TerraAmazon, which is used as a basis for this initiative, allows

  16. Fine root productivity varies along nitrogen and phosphorus gradients in high-rainfall mangrove forests of Micronesia

    USGS Publications Warehouse

    Cormier, Nicole; Twilley, Robert R.; Ewel, Katherine C.; Krauss, Ken W.

    2015-01-01

    Belowground biomass is thought to account for much of the total biomass in mangrove forests and may be related to soil fertility. The Yela River and the Sapwalap River, Federated States of Micronesia, contain a natural soil resource gradient defined by total phosphorus (P) density ranging from 0.05 to 0.42 mg cm−3 in different hydrogeomorphic settings. We used this fertility gradient to test the hypothesis that edaphic conditions constrain mangrove productivity through differential allocation of biomass to belowground roots. We removed sequential cores and implanted root ingrowth bags to measure in situ biomass and productivity, respectively. Belowground root biomass values ranged among sites from 0.448 ± 0.096 to 2.641 ± 0.534 kg m−2. Root productivity (roots ≤20 mm) did not vary significantly along the gradient (P = 0.3355) or with P fertilization after 6 months (P = 0.2968). Fine root productivity (roots ≤2 mm), however, did vary significantly among sites (P = 0.0363) and ranged from 45.88 ± 21.37 to 118.66 ± 38.05 g m−2 year−1. The distribution of total standing root biomass and fine root productivity followed patterns of N:P ratios as hypothesized, with larger root mass generally associated with lower relative P concentrations. Many of the processes of nutrient acquisition reported from nutrient-limited mangrove forests may also occur in forests of greater biomass and productivity when growing along soil nutrient gradients.

  17. Oviposition and Larval Habitat Preferences of the Saltwater Mosquito, Aedes vigilax, in a Subtropical Mangrove Forest in Queensland, Australia

    PubMed Central

    Knight, Jon; Griffin, Lachlan; Dale, Pat; Phinn, Stuart

    2012-01-01

    Our aim was to investigate the oviposition and larval habitats of the saltwater mosquito Aedes vigilax (Skuse) (Diptera: Culicidae) in a mangrove forest system in subtropical Queensland, Australia. Eggshells (indicators of oviposition) and larvae were sampled in three habitat classes that were depicted in a schematic model. Two classes were in depressions or basins, either with hummocks or dense pneumatophore substrates, both of which retained water after tidal flooding. The third class was in freely flushed mangroves that corresponded with more frequent tidal connections than the depression classes. ANOVA and Tukey-Kramer tests were used to analyze the data. The null hypotheses were rejected: the hummock class was a significant habitat based on both eggshell and larval data. The conclusion was that mosquito production in the mangrove system was distributed unevenly between habitat classes, and that the hummock class had conditions suited to the requirements of the immature stages of Ae. vigilax. This research has the potential to inform mosquito management strategies by focusing treatment on the problem habitats and underpinning habitat modifications including reducing water retention in the basins. PMID:22938052

  18. Effects of hydrology on red mangrove recruits

    USGS Publications Warehouse

    Doyle, Thomas W.

    2003-01-01

    Coastal wetlands along the Gulf of Mexico have been experiencing significant shifts in hydrology and salinity levels over the past century as a result of changes in sea level and freshwater drainage patterns. Local land management in coastal zones has also impacted the hydrologic regimes of salt marshes and mangrove areas. Parks and refuges in south Florida that contain mangrove forests have, in some cases, been ditched or impounded to control mosquito outbreaks and to foster wildlife use. And while mangroves dominate the subtropical coastlines of Florida and thrive in saltwater environments, little is known about how they respond to changes in hydrology under managed or variable tidal conditions. USGS researchers designed a study to evaluate the basic hydrological requirements of mangroves so that their health and survival may be more effectively managed in controlled impoundments and restored wetlands. Mangroves are commonly found in the intertidal zone (between low and high tides) in a rather broad spectrum of hydrologic settings. Because they thrive at the interface of land and sea, mangroves are subject to changes in freshwater flow (flow rate, nutrients, pollutants) and to marine influences (sea-level rise, salinity). Salinity has long been recognized as a controlling factor that determines the health and distribution of mangrove forests. Field and experimental observations indicate that most mangrove species achieve their highest growth potential under brackish conditions (modest salinity) between 10 and 20 parts per thousand (ppt). Yet, if provided with available propagules, successful regeneration, and limited competition from other plants, then mangroves can survive and thrive in freshwater systems as well. Because little is known about the growthand survival patterns of mangrove species relative to changing hydrology, USGS scientists conducted greenhouse and field experiments to determine how flooded or drained patterns of hydrology would influence

  19. Ranging, Activity and Habitat Use by Tigers in the Mangrove Forests of the Sundarban.

    PubMed

    Naha, Dipanjan; Jhala, Yadvendradev V; Qureshi, Qamar; Roy, Manjari; Sankar, Kalyansundaram; Gopal, Rajesh

    2016-01-01

    The Sundarban of India and Bangladesh (about 6000 km²) are the only mangrove forests inhabited by a sizeable population of tigers. The adjoining area also supports one of the highest human densities and experiences severe human-tiger conflicts. We used GPS-Satellite and VHF radio-collars on 6 (3 males and 3 female) tigers to study their ranging patterns and habitat preference. The average home range (95% Fixed Kernel) for resident females was 56.4 (SE 5.69) and for males it was 110 (SE 49) km². Tigers crossed an average of 5 water channels > 30 meters per day with a mean width of 54 meters, whereas channels larger than 400 meters were rarely crossed. Tigers spent over 58% of their time within Phoenix habitat but compositional analysis showed a habitat preference of the order Avicennia-Sonneratia > Phoenix > Ceriops > Barren > Water. Average daily distance moved was 4.6 km (range 0.1-23). Activity of tigers peaked between 05:00 hours and 10:00 hours showing some overlap with human activity. Territory boundaries were demarcated by large channels which tigers intensively patrolled. Extra caution should be taken while fishing or honey collection during early morning in Avicennia-Sonneratia and Phoenix habitat types along wide channels to reduce human-tiger conflict. Considering home-range core areas as exclusive, tiger density was estimated at 4.6 (SE range 3.6 to 6.7) tigers/100 km2 giving a total population of 76 (SE range 59-110) tigers in the Indian Sundarban. Reluctance of tigers to cross wide water channels combined with increasing commercial boat traffic and sea level rise due to climate change pose a real threat of fragmenting the Sundarban tiger population.

  20. Ranging, Activity and Habitat Use by Tigers in the Mangrove Forests of the Sundarban.

    PubMed

    Naha, Dipanjan; Jhala, Yadvendradev V; Qureshi, Qamar; Roy, Manjari; Sankar, Kalyansundaram; Gopal, Rajesh

    2016-01-01

    The Sundarban of India and Bangladesh (about 6000 km²) are the only mangrove forests inhabited by a sizeable population of tigers. The adjoining area also supports one of the highest human densities and experiences severe human-tiger conflicts. We used GPS-Satellite and VHF radio-collars on 6 (3 males and 3 female) tigers to study their ranging patterns and habitat preference. The average home range (95% Fixed Kernel) for resident females was 56.4 (SE 5.69) and for males it was 110 (SE 49) km². Tigers crossed an average of 5 water channels > 30 meters per day with a mean width of 54 meters, whereas channels larger than 400 meters were rarely crossed. Tigers spent over 58% of their time within Phoenix habitat but compositional analysis showed a habitat preference of the order Avicennia-Sonneratia > Phoenix > Ceriops > Barren > Water. Average daily distance moved was 4.6 km (range 0.1-23). Activity of tigers peaked between 05:00 hours and 10:00 hours showing some overlap with human activity. Territory boundaries were demarcated by large channels which tigers intensively patrolled. Extra caution should be taken while fishing or honey collection during early morning in Avicennia-Sonneratia and Phoenix habitat types along wide channels to reduce human-tiger conflict. Considering home-range core areas as exclusive, tiger density was estimated at 4.6 (SE range 3.6 to 6.7) tigers/100 km2 giving a total population of 76 (SE range 59-110) tigers in the Indian Sundarban. Reluctance of tigers to cross wide water channels combined with increasing commercial boat traffic and sea level rise due to climate change pose a real threat of fragmenting the Sundarban tiger population. PMID:27049644

  1. Ranging, Activity and Habitat Use by Tigers in the Mangrove Forests of the Sundarban

    PubMed Central

    Naha, Dipanjan; Jhala, Yadvendradev V.; Qureshi, Qamar; Roy, Manjari; Sankar, Kalyansundaram; Gopal, Rajesh

    2016-01-01

    The Sundarban of India and Bangladesh (about 6000 km²) are the only mangrove forests inhabited by a sizeable population of tigers. The adjoining area also supports one of the highest human densities and experiences severe human-tiger conflicts. We used GPS-Satellite and VHF radio-collars on 6 (3 males and 3 female) tigers to study their ranging patterns and habitat preference. The average home range (95% Fixed Kernel) for resident females was 56.4 (SE 5.69) and for males it was 110 (SE 49) km². Tigers crossed an average of 5 water channels > 30 meters per day with a mean width of 54 meters, whereas channels larger than 400 meters were rarely crossed. Tigers spent over 58% of their time within Phoenix habitat but compositional analysis showed a habitat preference of the order Avicennia-Sonneratia > Phoenix > Ceriops > Barren > Water. Average daily distance moved was 4.6 km (range 0.1–23). Activity of tigers peaked between 05:00 hours and 10:00 hours showing some overlap with human activity. Territory boundaries were demarcated by large channels which tigers intensively patrolled. Extra caution should be taken while fishing or honey collection during early morning in Avicennia-Sonneratia and Phoenix habitat types along wide channels to reduce human-tiger conflict. Considering home-range core areas as exclusive, tiger density was estimated at 4.6 (SE range 3.6 to 6.7) tigers/100 km2 giving a total population of 76 (SE range 59–110) tigers in the Indian Sundarban. Reluctance of tigers to cross wide water channels combined with increasing commercial boat traffic and sea level rise due to climate change pose a real threat of fragmenting the Sundarban tiger population. PMID:27049644

  2. Hurricane disturbance and recovery of carbon and energy balance in a tidal mangrove forest

    NASA Astrophysics Data System (ADS)

    Barr, J. G.; Engel, V.; Fuentes, J. D.; Smith, T.

    2009-12-01

    The goal of this presentation is to determine mangrove ecosystem function following a disturbance. Hurricane Wilma made landfall as a Category 3 storm along the western coast of the Florida Everglades in October 2005. The storm deposited large amounts of marine calcitic sediments. At a site 2 km inland from the center of landfall, 5 cm of sediments were deposited, and 30% of mature trees were defoliated and killed. At this site, tower based measurements of carbon dioxide eddy covariance and energy balance were started in 2004. Several years of repeated measurements of tree basal area, litterfall, root turnover, and peat surface elevations also pre-date the storm. Measurements resumed in 2006, providing an opportunity to examine the effects of hurricane disturbance on coastal ecosystem functioning. Following defoliation sensible heating decreased and latent heating increased. Reductions in sensible heating are attributed to decreased energy exchange at the forest crown and increased solar energy reaching the peat surface. Increases in latent heating are attributed to increased turbulent transport of latent heat fluxes from the saturated soil and water beneath the forest. Soil temperature and soil heat fluxes increased after the storm. Reductions in net ecosystem carbon assimilation rates (NEE) are apparent 4 years after the storm, though the rates are now approaching pre-storm values. The increased soil temperature following the storm presumably led to increased soil respiration which, along with the tree mortality, branch loss, and defoliation, explained the decreases in ecosystem-level carbon assimilation rates following the storm. Minimum half-hourly NEE values reached -25 μmol m-2 s-1 and -22 μmol m-2 s-1 before and after the storm, respectively. Daytime ecosystem respiration rates (Re) estimated using the intercept of light-response curves increased by an average of 1.2 μmol m-2 s-1 at a reference temperature of 20 oC during low tide periods. Nightime Re at

  3. Monitoring Change in Temperate Coniferous Forest Ecosystems

    NASA Technical Reports Server (NTRS)

    Williams, Darrel (Technical Monitor); Woodcock, Curtis E.

    2004-01-01

    The primary goal of this research was to improve monitoring of temperate forest change using remote sensing. In this context, change includes both clearing of forest due to effects such as fire, logging, or land conversion and forest growth and succession. The Landsat 7 ETM+ proved an extremely valuable research tool in this domain. The Landsat 7 program has generated an extremely valuable transformation in the land remote sensing community by making high quality images available for relatively low cost. In addition, the tremendous improvements in the acquisition strategy greatly improved the overall availability of remote sensing images. I believe that from an historical prespective, the Landsat 7 mission will be considered extremely important as the improved image availability will stimulate the use of multitemporal imagery at resolutions useful for local to regional mapping. Also, Landsat 7 has opened the way to global applications of remote sensing at spatial scales where important surface processes and change can be directly monitored. It has been a wonderful experience to have participated on the Landsat 7 Science Team. The research conducted under this project led to contributions in four general domains: I. Improved understanding of the information content of images as a function of spatial resolution; II. Monitoring Forest Change and Succession; III. Development and Integration of Advanced Analysis Methods; and IV. General support of the remote sensing of forests and environmental change. This report is organized according to these topics. This report does not attempt to provide the complete details of the research conducted with support from this grant. That level of detail is provided in the 16 peer reviewed journal articles, 7 book chapters and 5 conference proceedings papers published as part of this grant. This report attempts to explain how the various publications fit together to improve our understanding of how forests are changing and how to

  4. Vegetation Structure, Tree Volume and Biomass Estimation using Terrestrial Laser Scanning Remote Sensing: A Case Study of the Mangrove Forests in the Everglades National Park

    NASA Astrophysics Data System (ADS)

    Feliciano, E. A.; Wdowinski, S.; Potts, M. D.

    2012-12-01

    Mangrove forests are being threatened by accelerated climate change, sea level rise and coastal projects. Carbon/above ground biomass (AGB) losses due to natural or human intervention can affect global warming. Thus, it is important to monitor AGB fluctuations in mangrove forests similar to those inhabiting the Everglades National Park (ENP). Tree volume and tree wood specific density are two important measurements for the estimation of AGB (mass = volume * density). Wood specific density is acquired in the laboratory by analyzing stem cores acquired in the field. However, tree volume is a challenging task because trees resemble tapered surfaces. The majority of published studies estimate tree volume and biomass using allometric equations, which describe the size, shape, volume or AGB of a given population of trees. However, these equations can be extremely general and might not give a representative value of volume or AGB for a specific tree species. In order to have precise biomass estimations, other methodologies for tree volume estimation are needed. To overcome this problem, we use a state-of-the-art remote sensing tool known as ground-based LiDAR a.k.a Terrestrial Laser Scanner (TLS), which can be used to precisely measure vegetation structure and tree volume from its 3-D point cloud. We surveyed three mangrove communities: (Rhizophora mangle, Laguncuria racemosa and Avicennia germinans) in three different sites along Shark River Slough (SRS), which is the primary source of water to the ENP. Our sites included: small-, intermediate- and tall- size mangroves. Our ground measurements included both: traditional forestry surveys and TLS surveys for tree attributes (tree height and diameter at breast height (DBH)) comparison. These attributes are used as input to allometric equations for the estimation of tree volume and AGB. A total of 25 scans were collected in 2011 with a Leica ScanStation C10 TLS. The 3-D point cloud acquired from the TLS data revealed that

  5. Understanding sources of carbon from a coastal mangrove forest: Shark River - Everglades National Park

    NASA Astrophysics Data System (ADS)

    Palya, A. P.; Anderson, W. T.; Jaffe, R.; Swart, P. K.

    2012-12-01

    Tropical and subtropical estuaries, particularly those occupied by mangrove forests, sequester a large amount of carbon dioxide from the atmosphere to be stored in biomass and ultimately in sediments. However, a significant portion of this carbon is lost as dissolved organic carbon (DOC) exported to the ocean. Therefore, the processes that transform and transport DOC within estuarine systems are an important part of the global carbon cycle. Analysis of stable carbon isotopes can provide insight on carbon dynamics in these coastal environments. Although DOC is the largest pool of reduced carbon in the ocean, few measurements of δ13C-DOC have been made for marine waters. Low DOC:DIC ratios and interference from large halide concentrations make such measurements difficult, time consuming, and costly. We have developed an approach that allows for the simultaneous measurement of DOC and δ13C-DOC in marine waters. By coupling a carbon analyzer utilizing a wet chemical oxidation technique to a high sensitivity cavity ring down spectrometer (WCO-CRDS), we are able to analyze δ13C-DOC of marine waters with DOC concentrations as low as 3 ppm C. Our approach uses an ambient atmospheric CO2 CRDS system originally designed to measure at 300 ppm (pCO2) which is an order-of-magnitude more sensitive than standard CRDS systems. This method for seawater analysis was developed by maximizing both the sample and sodium persulfate reagent volumes used in the oxidation reaction, as well as increasing the sodium persulfate concentration. Additionally, we operate the WCO-CRDS system using ultra high purity nitrogen as a carrier gas to prevent the oxidation of halides which reduces damage to the machines. These parameters allow for complete oxidation of the DOC in the sample, which was confirmed using two DOC standards mixed in an artificial seawater with a salinity around 30 g/L, and produces a sufficient volume of CO2 for detection and measurement by the CRDS. This configuration

  6. Biodiversity of meiofauna in the intertidal khe nhan mudflat, can gio mangrove forest, vietnam with special emphasis on free living nematodes

    NASA Astrophysics Data System (ADS)

    Xuan, Quang Ngo; Vanreusel, Ann; Thanh, Nguyen Vu; Smol, Nic

    2007-09-01

    The ecological aspect of meiofaunal communities in Can Gio mangrove forest, Ho Chi Minh city, Vietnam has not been investigated before. The composition, distribution, density and biodiversity of meiofaunal communities were studied along an intertidal transect at the Khe Nhan mudflat. Each time, three replicate samples were collected in four stations along a transect following the water line from low tide level up to the mangrove forest edge. In total, 18 meiofaunal taxa were found with the dominant taxa belonging to Nematoda, Copepoda, Sarcomastigophora and Polychaeta. The densities of meiofauna ranged from 1156 inds/10 cm2 to 2082 inds/10 cm2. The increase in densities from the mangrove forest edge towards the low water line was significant. Along the mudflat transect, the biodiversity (expressed by different indices) was relatively high at different taxonomic levels but did not vary significantly along the mudflat except for taxa richness. Eighty nematode genera belonging to 24 families with Comesomatidae having the highest abundance 33.8 % were found. Theristus and Neochromadora decreased in densities from the lower water line towards the mangrove forest edge, while Paracomesoma and Hopperia are typical and more abundant at the middle of the mudflat. Halalaimus increased from high on the mudflat to the low water line.

  7. Sinomonas humi sp. nov., an amylolytic actinobacterium isolated from mangrove forest soil.

    PubMed

    Lee, Learn-Han; Azman, Adzzie-Shazleen; Zainal, Nurullhudda; Yin, Wai-Fong; Mutalib, Nurul-Syakima Ab; Chan, Kok-Gan

    2015-03-01

    Strain MUSC 117(T) was isolated from mangrove soil of the Tanjung Lumpur forest in Pahang, Malaysia. This bacterium was yellowish-white pigmented, Gram-staining-positive, rod-coccus shaped and non-motile. On the basis of 16S rRNA gene sequence, strain MUSC 117(T) exhibited highest sequence similarity to Sinomonas atrocyanea DSM 20127(T) (98.0 %), Sinomonas albida LC13(T) (97.9 %) and Sinomonas soli CW 59(T) (97.8 %), and lower (<97.6 %) sequence similarity to other species of the genus Sinomonas. DNA-DNA hybridization experiments revealed a low level of DNA-DNA relatedness (less than 27 %) between strain MUSC 117(T) and closely related species. Chemotaxonomically, the peptidoglycan type was A3α, containing the amino acids lysine, serine, glycine, alanine, glutamic acid and muramic acid. The whole-cell sugars detected were rhamnose, ribose, glucose, galactose and a smaller amount of mannose. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and five unidentified glycolipids. The major fatty acids (>10.0 %) of the cell membrane were anteiso-C15 : 0 (39.4 %), C18 : 1ω7c (17.7 %), anteiso-C17 : 0 (17.2 %) and iso-C16 : 0 (11.4 %). The predominant respiratory quinones detected were MK-9(H2) and MK-9. The DNA G+C content was 67.3 mol%. A comparison of BOX-PCR fingerprints indicated that strain MUSC 117(T) represented a unique DNA profile. Results based on a polyphasic approach showed that strain MUSC 117(T) represents a novel species of the genus Sinomonas, for which the name Sinomonas humi sp. nov. is proposed. The type strain of Sinomonas humi sp. nov. is MUSC 117(T) ( = DSM 29362(T) = MCCC 1K00410(T) = NBRC 110653(T)). PMID:25563924

  8. Phaeobacterium nitratireducens gen. nov., sp. nov., a phototrophic gammaproteobacterium isolated from a mangrove forest sediment sample.

    PubMed

    Nupur; Tanuku, Naga Radha Srinivas; Shinichi, Takaichi; Pinnaka, Anil Kumar

    2015-08-01

    A novel brown-coloured, Gram-negative-staining, rod-shaped, motile, phototrophic, purple sulfur bacterium, designated strain AK40T, was isolated in pure culture from a sediment sample collected from Coringa mangrove forest, India. Strain AK40T contained bacteriochlorophyll a and carotenoids of the rhodopin series as major photosynthetic pigments. Strain AK40T was able to grow photoheterotrophically and could utilize a number of organic substrates. It was unable to grow photoautotrophically and did not utilize sulfide or thiosulfate as electron donors. Thiamine and riboflavin were required for growth. The dominant fatty acids were C12 : 0, C16 : 0, C18 : 1ω7c and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH). The polar lipid profile of strain AK40T was found to contain diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and eight unidentified lipids. Q-10 was the predominant respiratory quinone. The DNA G+C content of strain AK40T was 65.5 mol%. 16S rRNA gene sequence comparisons indicated that the isolate represented a member of the family Chromatiaceae within the class Gammaproteobacteria. 16S rRNA gene sequence analysis indicated that strain AK40T was closely related to Phaeochromatium fluminis, with 95.2% pairwise sequence similarity to the type strain; sequence similarity to strains of other species of the family was 90.8-94.8%. Based on the sequence comparison data, strain AK40T was positioned distinctly outside the group formed by the genera Phaeochromatium, Marichromatium, Halochromatium, Thiohalocapsa, Rhabdochromatium and Thiorhodovibrio. Distinct morphological, physiological and genotypic differences from previously described taxa supported the classification of this isolate as a representative of a novel species in a new genus, for which the name Phaeobacterium nitratireducens gen. nov., sp. nov. is proposed. The type strain of Phaeobacterium nitratireducens is AK40T ( = JCM 19219T = MTCC 11824T

  9. Restoration of mangrove plantations and colonisation by native species in Leizhou bay, South China

    USGS Publications Warehouse

    Ren, H.; Jian, S.; Lu, H.; Zhang, Q.; Shen, W.; Han, W.; Yin, Z.; Guo, Q.

    2008-01-01

    To examine the natural colonisation of native mangrove species into remediated exotic mangrove stands in Leizhou Bay, South China, we compared soil physical-chemical properties, community structure and recruitments of barren mangrove areas, native mangrove species plantations, and exotic mangrove species-Sonneratia apetala Buch.Ham-between plantations and natural forest. We found that severely degraded mangrove stands could not regenerate naturally without human intervention due to severely altered local environments, whereas some native species had been recruited into the 4-10 year S. apetala plantations. In the first 10 years, the exotic species S. apetala grew better than native species such as Rhizophora stylosa Griff and Kandelia candel (Linn.) Druce. The mangrove plantation gradually affected soil physical and chemical properties during its recovery. The exotic S. apetala was more competitive than native species and its plantation was able to restore soil organic matter in about 14 years. Thus, S. apetala can be considered as a pioneer species to improve degraded habitats to facilitate recolonisation by native mangrove species. However, removal to control proliferation may be needed at late stages to facilitate growth of native species. To ensure sustainability of mangroves in South China, the existing mangrove wetlands must be managed as an ecosystem, with long-term scientific monitoring program in place. ?? 2007 The Ecological Society of Japan.

  10. Root proliferation in decaying roots and old root channels: A nutrient conservation mechanism in oligotrophic mangrove forests?

    USGS Publications Warehouse

    McKee, K.L.

    2001-01-01

    1. In oligotrophic habitats, proliferation of roots in nutrient-rich microsites may contribute to overall nutrient conservation by plants. Peat-based soils on mangrove islands in Belize are characterized by the presence of decaying roots and numerous old root channels (0.1-3.5 cm diameter) that become filled with living and highly branched roots of Rhizophora mangle and Avicennia germinans. The objectives of this study were to quantify the proliferation of roots in these microsites and to determine what causes this response. 2. Channels formed by the refractory remains of mangrove roots accounted for only 1-2% of total soil volume, but the proportion of roots found within channels varied from 9 to 24% of total live mass. Successive generations of roots growing inside increasingly smaller root channels were also found. 3. When artificial channels constructed of PVC pipe were buried in the peat for 2 years, those filled with nutrient-rich organic matter had six times more roots than empty or sand-filled channels, indicating a response to greater nutrient availability rather than to greater space or less impedance to root growth. 4. Root proliferation inside decaying roots may improve recovery of nutrients released from decomposing tissues before they can be leached or immobilized in this intertidal environment. Greatest root proliferation in channels occurred in interior forest zones characterized by greater soil waterlogging, which suggests that this may be a strategy for nutrient capture that minimizes oxygen losses from the whole root system. 5. Improved efficiency of nutrient acquisition at the individual plant level has implications for nutrient economy at the ecosystem level and may explain, in part, how mangroves persist and grow in nutrient-poor environments.

  11. Sedimentology of onshore tsunami deposits of the Indian Ocean tsunami, 2004 in the mangrove forest of the Curieuse Marine National Park, Seychelles

    NASA Astrophysics Data System (ADS)

    Nentwig, V.; Bahlburg, H.; Monthy, D.

    2012-12-01

    The Seychelles were severely affected by the December 26, 2004 tsunami in the Indian Ocean. Since the tsunami history of small islands often remains unclear due to a young historiography we conducted a study of onshore tsunami deposits on the Seychelles in order to understand the scale of impact of the 2004 Indian Ocean tsunami and potential predecessors. As part of this project we found and studied onshore tsunami deposits in the mangrove forest at Old Turtle Pond bay on the east coast of Curieuse Island. The 2004 Indian Ocean tsunami caused a change of habitat due to sedimentation of an extended sand sheet in the mangrove forest. We present results of the first detailed sedimentological study of onshore tsunami deposits of the 2004 Indian Ocean tsunami conducted on the Seychelles. The Curieuse mangrove forest at Old Turtle Pond bay is part of the Curieuse Marine National Park. It is thus protected from anthropogenic interference. Towards the sea it was shielded until the tsunami by a 500 m long and 1.5 m high causeway which was set up in 1909 as a sediment trap. The causeway was destroyed by the 2004 Indian Ocean Tsunami. The silt to fine sand sized and organic rich mangrove soil was subsequently covered by carbonate fine to medium sand (1.5 to 2.1 Φ) containing coarser carbonate shell debris which had been trapped outside the mangrove bay before the tsunami. The tsunami deposited a sand sheet which is organized into different lobes. They extend landwards to different inundation distances as a function of morphology. Maximum inundation distance is 200 m. The sediments often cover the pneumatophores of the mangroves. No landward fining trend of the sand sheet has been observed. On the different sand lobes carbonate-cemented sandstone debris ranging in size from 0.5 up to 12 cm occurs. Also numerous mostly fragmented shells of bivalves and molluscs were distributed on top of the sand lobes. Intact bivalve shells were mostly positioned with the convex side upwards

  12. The role of freezing in setting the latitudinal limits of mangrove forests.

    PubMed

    Stuart, S A; Choat, B; Martin, K C; Holbrook, N M; Ball, M C

    2007-01-01

    Mangrove trees dominate coastal vegetation in tropical regions, but are completely replaced by herbaceous salt marshes at latitudes above 32 degrees N and 40 degrees S. Because water deficit can increase damage caused by freezing, we hypothesized that mangroves, which experience large deficits as a result of saline substrates, would suffer freeze-induced xylem failure. Vulnerability to freeze-induced xylem embolism was examined in the most poleward mangrove species in North America, in an area where freezing is rare but severe, and in Australia, in an area where freezing is frequent but mild. Percentage loss in hydraulic conductivity was measured following manipulations of xylem tension; xylem sap ion concentration was determined using X-ray microanalysis. Species with wider vessels suffered 60-100% loss of hydraulic conductivity after freezing and thawing under tension, while species with narrower vessels lost as little as 13-40% of conductivity. These results indicate that freeze-induced embolism may play a role in setting the latitudinal limits of distribution in mangroves, either through massive embolism following freezing, or through constraints on water transport as a result of vessel size. PMID:17244052

  13. Estimating Carbon STOCK Changes of Mangrove Forests Using Satellite Imagery and Airborne LiDAR Data in the South Sumatra State, Indonesia

    NASA Astrophysics Data System (ADS)

    Maeda, Y.; Fukushima, A.; Imai, Y.; Tanahashi, Y.; Nakama, E.; Ohta, S.; Kawazoe, K.; Akune, N.

    2016-06-01

    The purposes of this study were 1) to estimate the biomass in the mangrove forests using satellite imagery and airborne LiDAR data, and 2) to estimate the amount of carbon stock changes using biomass estimated. The study area is located in the coastal area of the South Sumatra state, Indonesia. This area is approximately 66,500 ha with mostly flat land features. In this study, the following procedures were carried out: (1) Classification of types of tree species using Satellite imagery in the study area, (2) Development of correlation equations between spatial volume based on LiDAR data and biomass stock based on field survey for each types of tree species, and estimation of total biomass stock and carbon stock using the equation, and (3) Estimation of carbon stock change using Chronological Satellite Imageries. The result showed the biomass and the amount of carbon stock changes can be estimated with high accuracy, by combining the spatial volume based on airborne LiDAR data with the tree species classification based on satellite imagery. Quantitative biomass monitoring is in demand for projects related to REDD+ in developing countries, and this study showed that combining airborne LiDAR data with satellite imagery is one of the effective methods of monitoring for REDD+ projects.

  14. Monitoring trees outside forests: a review.

    PubMed

    Schnell, Sebastian; Kleinn, Christoph; Ståhl, Göran

    2015-09-01

    Trees outside forests (TOFs) are an important natural resource that contributes substantially to national biomass and carbon stocks and to the livelihood of people in many regions. Over the last decades, decision makers have become increasingly aware of the importance of TOF, and as a consequence, this tree resource is nowadays often considered in forest monitoring systems. Our review shows that in many cases, TOF are included in national forest inventories, applying traditional methodologies with relatively sparse networks of field sample plots. Only in some countries, such as India, the design of the inventories has considered the special features of how TOFs occur in the landscape. Several research studies utilising remote sensing for monitoring TOF have been conducted lately, but very few studies include comparative studies to optimise sampling strategies for TOF. Our review indicates that methods combining remote sensing and field surveys appear to be very promising, especially when remote sensing techniques that assess both the horizontal and vertical structures of tree resources are applied. For example, two-phase sampling strategies with laser scanning in the first phase and a field survey in the second phase appear to be effective for assessing TOF resources. However, TOFs often exhibit different characteristics than forest trees. Thus, to improve TOF monitoring, there is often a need to develop models, e.g. for biomass assessment, that are specifically adapted to this tree resource. Alternatively, field-based remote sensing methods that provide structural information about individual trees, notably terrestrial laser scanning, could be further developed for TOF monitoring applications. This also would have a potential to reduce the problem of accessing TOF during field surveys, which is a problem, for example, in countries where TOF are present on intensively utilised private grounds like gardens and agricultural fields. PMID:26318320

  15. Monitoring trees outside forests: a review.

    PubMed

    Schnell, Sebastian; Kleinn, Christoph; Ståhl, Göran

    2015-09-01

    Trees outside forests (TOFs) are an important natural resource that contributes substantially to national biomass and carbon stocks and to the livelihood of people in many regions. Over the last decades, decision makers have become increasingly aware of the importance of TOF, and as a consequence, this tree resource is nowadays often considered in forest monitoring systems. Our review shows that in many cases, TOF are included in national forest inventories, applying traditional methodologies with relatively sparse networks of field sample plots. Only in some countries, such as India, the design of the inventories has considered the special features of how TOFs occur in the landscape. Several research studies utilising remote sensing for monitoring TOF have been conducted lately, but very few studies include comparative studies to optimise sampling strategies for TOF. Our review indicates that methods combining remote sensing and field surveys appear to be very promising, especially when remote sensing techniques that assess both the horizontal and vertical structures of tree resources are applied. For example, two-phase sampling strategies with laser scanning in the first phase and a field survey in the second phase appear to be effective for assessing TOF resources. However, TOFs often exhibit different characteristics than forest trees. Thus, to improve TOF monitoring, there is often a need to develop models, e.g. for biomass assessment, that are specifically adapted to this tree resource. Alternatively, field-based remote sensing methods that provide structural information about individual trees, notably terrestrial laser scanning, could be further developed for TOF monitoring applications. This also would have a potential to reduce the problem of accessing TOF during field surveys, which is a problem, for example, in countries where TOF are present on intensively utilised private grounds like gardens and agricultural fields.

  16. Differential responses of net ecosystem exchange of carbon dioxide to light and temperature between spring and neap tides in subtropical mangrove forests.

    PubMed

    Li, Qing; Lu, Weizhi; Chen, Hui; Luo, Yiqi; Lin, Guanghui

    2014-01-01

    The eddy flux data with field records of tidal water inundation depths of the year 2010 from two mangroves forests in southern China were analyzed to investigate the tidal effect on mangrove carbon cycle. We compared the net ecosystem exchange (NEE) and its responses to light and temperature, respectively, between spring tide and neap tide inundation periods. For the most time of the year 2010, higher daytime NEE values were found during spring tides than during neap tides at both study sites. Regression analysis of daytime NEE to photosynthetically active radiation (PAR) using the Landsberg model showed increased sensitivity of NEE to PAR with higher maximum photosynthetic rate during spring tides than neap tides. In contrast, the light compensation points acquired from the regression function of the Landsberg model were smaller during spring tides than neap tides in most months. The dependence of nighttime NEE on soil temperature was lower under spring tide than under neap tides. All these results above indicated that ecosystem carbon uptake rates of mangrove forests were strengthened, while ecosystem respirations were inhibited during spring tides in comparison with those during neap tides, which needs to be considered in modeling mangrove ecosystem carbon cycle under future sea level rise scenarios.

  17. Differential Responses of Net Ecosystem Exchange of Carbon Dioxide to Light and Temperature between Spring and Neap Tides in Subtropical Mangrove Forests

    PubMed Central

    Li, Qing; Lu, Weizhi; Chen, Hui; Luo, Yiqi; Lin, Guanghui

    2014-01-01

    The eddy flux data with field records of tidal water inundation depths of the year 2010 from two mangroves forests in southern China were analyzed to investigate the tidal effect on mangrove carbon cycle. We compared the net ecosystem exchange (NEE) and its responses to light and temperature, respectively, between spring tide and neap tide inundation periods. For the most time of the year 2010, higher daytime NEE values were found during spring tides than during neap tides at both study sites. Regression analysis of daytime NEE to photosynthetically active radiation (PAR) using the Landsberg model showed increased sensitivity of NEE to PAR with higher maximum photosynthetic rate during spring tides than neap tides. In contrast, the light compensation points acquired from the regression function of the Landsberg model were smaller during spring tides than neap tides in most months. The dependence of nighttime NEE on soil temperature was lower under spring tide than under neap tides. All these results above indicated that ecosystem carbon uptake rates of mangrove forests were strengthened, while ecosystem respirations were inhibited during spring tides in comparison with those during neap tides, which needs to be considered in modeling mangrove ecosystem carbon cycle under future sea level rise scenarios. PMID:25133267

  18. Differential responses of net ecosystem exchange of carbon dioxide to light and temperature between spring and neap tides in subtropical mangrove forests.

    PubMed

    Li, Qing; Lu, Weizhi; Chen, Hui; Luo, Yiqi; Lin, Guanghui

    2014-01-01

    The eddy flux data with field records of tidal water inundation depths of the year 2010 from two mangroves forests in southern China were analyzed to investigate the tidal effect on mangrove carbon cycle. We compared the net ecosystem exchange (NEE) and its responses to light and temperature, respectively, between spring tide and neap tide inundation periods. For the most time of the year 2010, higher daytime NEE values were found during spring tides than during neap tides at both study sites. Regression analysis of daytime NEE to photosynthetically active radiation (PAR) using the Landsberg model showed increased sensitivity of NEE to PAR with higher maximum photosynthetic rate during spring tides than neap tides. In contrast, the light compensation points acquired from the regression function of the Landsberg model were smaller during spring tides than neap tides in most months. The dependence of nighttime NEE on soil temperature was lower under spring tide than under neap tides. All these results above indicated that ecosystem carbon uptake rates of mangrove forests were strengthened, while ecosystem respirations were inhibited during spring tides in comparison with those during neap tides, which needs to be considered in modeling mangrove ecosystem carbon cycle under future sea level rise scenarios. PMID:25133267

  19. Decomposition of mangrove roots: Effects of location, nutrients, species identity and mix in a Kenyan forest

    NASA Astrophysics Data System (ADS)

    Huxham, Mark; Langat, Joseph; Tamooh, Fredrick; Kennedy, Hilary; Mencuccini, Maurizio; Skov, Martin W.; Kairo, James

    2010-06-01

    Mangrove trees may allocate >50% of their biomass to roots. Dead roots often form peat, which can make mangroves significant carbon sinks and allow them to raise the soil surface and thus survive rising sea levels. Understanding mangrove root production and decomposition is hence of theoretical and applied importance. The current work explored the effects of species, site, and root size and root nutrients on decomposition. Decomposition of fine (≤3 mm diameter) and coarse (>3 mm diameter, up to a maximum of ˜9 mm) roots from three mangrove species, Avicennia marina, Bruguiera gymnorrhiza and Ceriops tagal was measured over 12 months at 6 sites along a tidal gradient in Gazi Bay, Kenya. C:N and P:N ratios in fresh and decomposed roots were measured, and the effects on decomposition of root size and age, of mixing roots from A. marina and C. tagal, of enriching B. gymnorrhiza roots with N and P and of artefacts caused by bagging roots were recorded. There were significant differences between species, with 76, 47 and 44 % mean dry weight lost after one year for A. marina, B. gymnorrhiza and C. tagal respectively, and between sites, with generally slower decomposition at dryer, high tidal areas. N enriched B. gymnorrhiza roots decomposed significantly faster than un-enriched controls; there was no effect of P enrichment. Mixing A. marina and C. tagal roots caused significantly enhanced decomposition in C. tagal. These results suggest that N availability was an important determinant of decomposition, since differences between species reflected the initial C: N ratios. The relatively slow decomposition rates recorded concur with other studies, and may overestimate natural rates, since larger (10-20 mm diameter), more mature and un-bagged roots all showed significantly slower rates.

  20. Geospatial monitoring and prioritization of forest fire incidences in Andhra Pradesh, India.

    PubMed

    Manaswini, G; Sudhakar Reddy, C

    2015-10-01

    Forest fire has been identified as one of the key environmental issue for long-term conservation of biodiversity and has impact on global climate. Spatially multiple observations are necessary for monitoring of forest fires in tropics for understanding conservation efficacy and sustaining biodiversity in protected areas. The present work was carried out to estimate the spatial extent of forest burnt areas and fire frequency using Resourcesat Advanced Wide Field Sensor (AWiFS) data (2009, 2010, 2012, 2013 and 2014) in Andhra Pradesh, India. The spatio-temporal analysis shows that an area of 7514.10 km(2) (29.22% of total forest cover) has been affected by forest fires. Six major forest types are distributed in Andhra Pradesh, i.e. semi-evergreen, moist deciduous, dry deciduous, dry evergreen, thorn and mangroves. Of the total forest burnt area, dry deciduous forests account for >75%. District-wise analysis shows that Kurnool, Prakasam and Cuddapah have shown >100 km(2) of burnt area every year. The total forest burnt area estimate covering protected areas ranges between 6.9 and 22.3% during the study period. Spatial burnt area analysis for protected areas in 2014 indicates 37.2% of fire incidences in the Nagarjunasagar Srisailam Tiger Reserve followed by 20.2 % in the Sri Lankamalleswara Wildlife Sanctuary, 20.1% in the Sri Venkateswara Wildlife Sanctuary and 17.4% in the Gundla Brahmeswaram Wildlife Sanctuary. The analysis of cumulative fire occurrences from 2009 to 2014 has helped in delineation of conservation priority hotspots using a spatial grid cell approach. Conservation priority hotspots I and II are distributed in major parts of study area including protected areas of the Nagarjunasagar Srisailam Tiger Reserve and Gundla Brahmeswaram Wildlife Sanctuary. The spatial database generated will be useful in studies related to influence of fires on species adaptability, ecological damage assessment and conservation planning. PMID:26350795

  1. Geospatial monitoring and prioritization of forest fire incidences in Andhra Pradesh, India.

    PubMed

    Manaswini, G; Sudhakar Reddy, C

    2015-10-01

    Forest fire has been identified as one of the key environmental issue for long-term conservation of biodiversity and has impact on global climate. Spatially multiple observations are necessary for monitoring of forest fires in tropics for understanding conservation efficacy and sustaining biodiversity in protected areas. The present work was carried out to estimate the spatial extent of forest burnt areas and fire frequency using Resourcesat Advanced Wide Field Sensor (AWiFS) data (2009, 2010, 2012, 2013 and 2014) in Andhra Pradesh, India. The spatio-temporal analysis shows that an area of 7514.10 km(2) (29.22% of total forest cover) has been affected by forest fires. Six major forest types are distributed in Andhra Pradesh, i.e. semi-evergreen, moist deciduous, dry deciduous, dry evergreen, thorn and mangroves. Of the total forest burnt area, dry deciduous forests account for >75%. District-wise analysis shows that Kurnool, Prakasam and Cuddapah have shown >100 km(2) of burnt area every year. The total forest burnt area estimate covering protected areas ranges between 6.9 and 22.3% during the study period. Spatial burnt area analysis for protected areas in 2014 indicates 37.2% of fire incidences in the Nagarjunasagar Srisailam Tiger Reserve followed by 20.2 % in the Sri Lankamalleswara Wildlife Sanctuary, 20.1% in the Sri Venkateswara Wildlife Sanctuary and 17.4% in the Gundla Brahmeswaram Wildlife Sanctuary. The analysis of cumulative fire occurrences from 2009 to 2014 has helped in delineation of conservation priority hotspots using a spatial grid cell approach. Conservation priority hotspots I and II are distributed in major parts of study area including protected areas of the Nagarjunasagar Srisailam Tiger Reserve and Gundla Brahmeswaram Wildlife Sanctuary. The spatial database generated will be useful in studies related to influence of fires on species adaptability, ecological damage assessment and conservation planning.

  2. Assessing forest products usage and local residents' perception of environmental changes in peri-urban and rural mangroves of Cameroon, Central Africa

    PubMed Central

    2011-01-01

    Background Deforestation is one of the most ubiquitous forms of land degradation worldwide. Although remote sensing and aerial photographs can supply valuable information on land/use cover changes, they may not regularly be available for some tropical coasts (e.g., Cameroon estuary) where cloud cover is frequent. With respect to mangroves, researchers are now employing local knowledge as an alternative means of understanding forest disturbances. This paper was primarily aimed at assessing the mangrove forest products usage, along with the local people's perceptions on environmental changes, between Littoral (Cameroon estuary) and Southern (mouth of the Nyong River and Mpalla village) regions of Cameroon. Methods The data from both locations were obtained through conducting household interviews and field observations. Results In the Cameroon estuary (Littoral region), 69.23% of respondents (mostly elders) could distinguish two to four mangrove plants, whereas the informants (65.45%) in the mouth of the Nyong River and Mpalla village (mostly young people interviewed from the Southern region) are familiar with only one or two commonly found mangroves. Also, more respondents from the Cameroon estuary are depending on mangroves for fuelwood (Rhizophora spp.) and housing (Rhizophora spp., Avicennia germinans (L.) Stearn and Nypa fruticans (Thumb.) Wurmb.) purposes, in contrast to Nyong River mouth and Mpalla village. Although local people perceived wood extraction as a greater disruptive factor, there are several causes for mangrove depletion in the Cameroon estuary. Among others, over-harvesting, clear-felled corridors, sand extraction and housing were found important. Furthermore, a decline in mangrove fauna composition (in terms of fishery products) was recorded in the Littoral as well as Southern regions. However, the causes of such perceived negative changes were not similar in both cases. Conclusions Findings of this study highlight the need to improve sustainable

  3. Combining satellite data for better tropical forest monitoring

    NASA Astrophysics Data System (ADS)

    Reiche, Johannes; Lucas, Richard; Mitchell, Anthea L.; Verbesselt, Jan; Hoekman, Dirk H.; Haarpaintner, Jörg; Kellndorfer, Josef M.; Rosenqvist, Ake; Lehmann, Eric A.; Woodcock, Curtis E.; Seifert, Frank Martin; Herold, Martin

    2016-02-01

    Implementation of policies to reduce forest loss challenges the Earth observation community to improve forest monitoring. An important avenue for progress is the use of new satellite missions and the combining of optical and synthetic aperture radar sensor data.

  4. The risk assessment of heavy metals in Futian mangrove forest sediment in Shenzhen Bay (South China) based on SEM-AVS analysis.

    PubMed

    Chai, Minwei; Shen, Xiaoxue; Li, Ruili; Qiu, Guoyu

    2015-08-15

    The risks of heavy metal in Futian mangrove forest sediment were assessed using the acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) methods. The results indicated that AVS distributions were more variable than the SEM distributions at all 16 sampling sites. The positive correlation between AVS and SEM indicated that their similar formative and existing conditions and that AVS acted as an important carrier for SEM. The major SEM component was Zn (69.7.3-94.2%), whereas the Cd contribution (the most toxic metal present) to SEM was no more than 1%. The possible adverse effects caused by heavy metals at ten sampling sites may be due to higher levels of SEMs, rather than AVSs. The total organic carbon (TOC) was an important metal-binding phase in the sediments. Taking into account the TOC concentration, there were no adverse effects due to heavy metals in any of the Futian mangrove forest sediments. PMID:26028168

  5. The risk assessment of heavy metals in Futian mangrove forest sediment in Shenzhen Bay (South China) based on SEM-AVS analysis.

    PubMed

    Chai, Minwei; Shen, Xiaoxue; Li, Ruili; Qiu, Guoyu

    2015-08-15

    The risks of heavy metal in Futian mangrove forest sediment were assessed using the acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) methods. The results indicated that AVS distributions were more variable than the SEM distributions at all 16 sampling sites. The positive correlation between AVS and SEM indicated that their similar formative and existing conditions and that AVS acted as an important carrier for SEM. The major SEM component was Zn (69.7.3-94.2%), whereas the Cd contribution (the most toxic metal present) to SEM was no more than 1%. The possible adverse effects caused by heavy metals at ten sampling sites may be due to higher levels of SEMs, rather than AVSs. The total organic carbon (TOC) was an important metal-binding phase in the sediments. Taking into account the TOC concentration, there were no adverse effects due to heavy metals in any of the Futian mangrove forest sediments.

  6. Mangrove Rehabilitation and Intertidal Biodiversity: a Study in the Ranong Mangrove Ecosystem, Thailand

    NASA Astrophysics Data System (ADS)

    Macintosh, D. J.; Ashton, E. C.; Havanon, S.

    2002-09-01

    ocypodids were more abundant than grapsids in the degraded concession forest area. Snails of the families Neritidae and Ellobiidae were the most abundant molluscs in the mature forest, whereas Littoriinidae, Assimineidae and Potamidae species were more representative of the younger plantation sites. The findings from this study suggest that some of these well represented families of mangrove macrofauna could be used as indicators of ecological change as part of a long term environmental monitoring programme in Ranong and other areas in Southeast Asia where mangroves are being rehabilitated.

  7. Export of inorganic carbon from two Southeast Asian mangrove forests to adjacent estuaries as estimated by the stable isotope composition of dissolved inorganic carbon

    NASA Astrophysics Data System (ADS)

    Miyajima, Toshihiro; Tsuboi, Yoshie; Tanaka, Yoshiyuki; Koike, Isao

    2009-03-01

    The influence of mangrove forests on the dynamics of dissolved inorganic carbon (DIC) in tropical estuaries was estimated quantitatively using newly developed isotope (δ13C) mass balance models that take into account both the input of DIC and the air-water exchange of CO2. To this aim, the concentration and δ13C of DIC were determined across the salinity gradient of two river estuaries facing the Andaman Sea. The longitudinal distribution of DIC could be explained by conservative mixing of the river water and seawater DIC in the low-discharge period (March 2006), while a net accumulation of DIC up to 190 μmol L-1 was observed in the high-discharge period (December 2006). δ13CDIC values were generally lower than expected for the mixing of the river water and seawater DIC, due to the 13C-depleted DIC inputs from the riverside mangroves. The concentration of mangrove-derived DIC in the estuarine waters was estimated by the proposed models to be as much as 856 μmol L-1, and was higher during the low-discharge period. This suggested that the mangroves exported much higher levels of DIC to the estuaries than indicated by the net accumulation of DIC. Our results confirm that mangroves function as an effective CO2 pump that takes CO2 from the atmosphere and releases it into estuarine waters. This study illustrates that δ13CDIC is a sensitive and quantitative indicator for DIC emission to the sea from coastal wetlands including mangroves.

  8. Sediment accretion and organic carbon burial relative to sea-level rise and storm events in two mangrove forests in Everglades National Park

    USGS Publications Warehouse

    Smoak, Joseph M.; Breithaupt, Joshua L.; Smith, Thomas J.; Sanders, Christian J.

    2013-01-01

    The goal of this investigation was to examine how sediment accretion and organic carbon (OC) burial rates in mangrove forests respond to climate change. Specifically, will the accretion rates keep pace with sea-level rise, and what is the source and fate of OC in the system? Mass accumulation, accretion and OC burial rates were determined via 210Pb dating (i.e. 100 year time scale) on sediment cores collected from two mangrove forest sites within Everglades National Park, Florida (USA). Enhanced mass accumulation, accretion and OC burial rates were found in an upper layer that corresponded to a well-documented storm surge deposit. Accretion rates were 5.9 and 6.5 mm yr−1 within the storm deposit compared to overall rates of 2.5 and 3.6 mm yr−1. These rates were found to be matching or exceeding average sea-level rise reported for Key West, Florida. Organic carbon burial rates were 260 and 393 g m−2 yr−1 within the storm deposit compared to 151 and 168 g m−2 yr−1 overall burial rates. The overall rates are similar to global estimates for OC burial in marine wetlands. With tropical storms being a frequent occurrence in this region the resulting storm surge deposits are an important mechanism for maintaining both overall accretion and OC burial rates. Enhanced OC burial rates within the storm deposit could be due to an increase in productivity created from higher concentrations of phosphorus within storm-delivered sediments and/or from the deposition of allochthonous OC. Climate change-amplified storms and sea-level rise could damage mangrove forests, exposing previously buried OC to oxidation and contribute to increasing atmospheric CO2 concentrations. However, the processes described here provide a mechanism whereby oxidation of OC would be limited and the overall OC reservoir maintained within the mangrove forest sediments.

  9. Aerosol characterization over Sundarban mangrove forest at the north-east coast of Bay of Bengal, India

    NASA Astrophysics Data System (ADS)

    Chatterjee, Abhijit; Das, Sanat Kumar; Sarkar, Chirantan; Ghosh, Sanjay; Raha, Sibaji; Singh, Soumendra; Roy, Arindam

    2016-07-01

    A comprehensive study was conducted on chemical characterization of size segregated and cumulative aerosols during winter, 2015 and summer 2016 over a remote mangrove forest at Sundarban at the north-east coast of Bay of Bengal. Aerosols originated from the surf zone at the land-ocean boundary of Sundarban mangrove forest and aerosols advected from Kolkata and other metropolitan and urban cities at Indo-Gangetic Plain were characterized in terms of major water soluble inorganic species. Attempt was made to investigate the combined effect of locally generated sea-salt and advected anthropogenic aerosols could change the pristine marine character at this region during the above mentioned periods. Significant chloride depletion from sea-salt aerosols was observed in coarse and ultrafine mode compared to fine mode in winter whereas reverse trend was observed during summer. On an average the chloride to sodium ratio in PM10 aerosol was found to be around 0.6 which was much lower than that in sea-water. It was observed that non-sea-sulphate and nitrate aerosols were the major species depleting chloride from sea-salt aerosols. This supported the interaction between fresh marine and polluted anthropogenic aerosols. The average concentration of PM10 aerosols was 64 μg m-3 in winter and 89 μg m-3 in summer. Major water soluble ionic species were used for the source apportionment of aerosol during the two seasons. On an average it was observed that 60-70 % of total PM10 aerosols were constituted by the major water soluble ionic species. Emission flux and deposition flux of aerosols were also studied over this remote forest region. It was also observed that anthropogenic ionic species were mostly accumulated in the ultrafine and fine mode region both during winter and summer. On the other hand sea-salt species were mostly accumulated in the coarse mode region. Sulphate aerosol showed bimodal distribution with prominent peaks both at ultrafine/fine and coarse mode region

  10. Burrows of the Semi-Terrestrial Crab Ucides cordatus Enhance CO2 Release in a North Brazilian Mangrove Forest

    PubMed Central

    Pülmanns, Nathalie; Diele, Karen; Mehlig, Ulf; Nordhaus, Inga

    2014-01-01

    Ucides cordatus is an abundant mangrove crab in Brazil constructing burrows of up to 2 m depth. Sediment around burrows may oxidize during low tides. This increase in sediment-air contact area may enhance carbon degradation processes. We hypothesized that 1) the sediment CO2 efflux rate is greater with burrows than without and 2) the reduction potential in radial profiles in the sediment surrounding the burrows decreases gradually, until approximating non-bioturbated conditions. Sampling was conducted during the North Brazilian wet season at neap tides. CO2 efflux rates of inhabited burrows and plain sediment were measured with a CO2/H2O gas analyzer connected to a respiration chamber. Sediment redox potential, pH and temperature were measured in the sediment surrounding the burrows at horizontal distances of 2, 5, 8 and 15 cm at four sediment depths (1, 10, 30 and 50 cm) and rH values were calculated. Sediment cores (50 cm length) were taken to measure the same parameters for plain sediment. CO2 efflux rates of plain sediment and individual crab burrows with entrance diameters of 7 cm were 0.7–1.3 µmol m−2 s−1 and 0.2–0.4 µmol burrows−1 s−1, respectively. CO2 released from a Rhizophora mangle dominated forest with an average of 1.7 U. cordatus burrows−1 m−2 yielded 1.0–1.7 µmol m−2 s−1, depending on the month and burrow entrance diameter. Laboratory experiments revealed that 20–60% of the CO2 released by burrows originated from crab respiration. Temporal changes in the reduction potential in the sediment surrounding the burrows did not influence the CO2 release from burrows. More oxidized conditions of plain sediment over time may explain the increase in CO2 release until the end of the wet season. CO2 released by U. cordatus and their burrows may be a significant pathway of CO2 export from mangrove sediments and should be considered in mangrove carbon budget estimates. PMID:25313661

  11. Burrows of the semi-terrestrial crab Ucides cordatus enhance CO2 release in a North Brazilian mangrove forest.

    PubMed

    Pülmanns, Nathalie; Diele, Karen; Mehlig, Ulf; Nordhaus, Inga

    2014-01-01

    Ucides cordatus is an abundant mangrove crab in Brazil constructing burrows of up to 2 m depth. Sediment around burrows may oxidize during low tides. This increase in sediment-air contact area may enhance carbon degradation processes. We hypothesized that 1) the sediment CO2 efflux rate is greater with burrows than without and 2) the reduction potential in radial profiles in the sediment surrounding the burrows decreases gradually, until approximating non-bioturbated conditions. Sampling was conducted during the North Brazilian wet season at neap tides. CO2 efflux rates of inhabited burrows and plain sediment were measured with a CO2/H2O gas analyzer connected to a respiration chamber. Sediment redox potential, pH and temperature were measured in the sediment surrounding the burrows at horizontal distances of 2, 5, 8 and 15 cm at four sediment depths (1, 10, 30 and 50 cm) and rH values were calculated. Sediment cores (50 cm length) were taken to measure the same parameters for plain sediment. CO2 efflux rates of plain sediment and individual crab burrows with entrance diameters of 7 cm were 0.7-1.3 µmol m(-2) s(-1) and 0.2-0.4 µmol burrows(-1) s(-1), respectively. CO2 released from a Rhizophora mangle dominated forest with an average of 1.7 U. cordatus burrows(-1) m(-2) yielded 1.0-1.7 µmol m(-2) s(-1), depending on the month and burrow entrance diameter. Laboratory experiments revealed that 20-60% of the CO2 released by burrows originated from crab respiration. Temporal changes in the reduction potential in the sediment surrounding the burrows did not influence the CO2 release from burrows. More oxidized conditions of plain sediment over time may explain the increase in CO2 release until the end of the wet season. CO2 released by U. cordatus and their burrows may be a significant pathway of CO2 export from mangrove sediments and should be considered in mangrove carbon budget estimates. PMID:25313661

  12. Occurrence of species-rich crab fauna in a human-impacted mangrove forest questions the application of community analysis as an environmental assessment tool

    NASA Astrophysics Data System (ADS)

    Geist, Simon Joscha; Nordhaus, Inga; Hinrichs, Saskia

    2012-01-01

    Diversity and composition of the intertidal brachyuran crab community in the Segara Anakan Lagoon (SAL), Java, Indonesia, during the dry season of 2005 and the rainy season of 2006, shows that crab community composition and structure alone appeared to be poor indicators for the state of a forest in terms of tree diversity and wood-cutting intensity. The lagoon is surrounded by the largest mangrove stand in Java and is under constant anthropogenic pressure, mainly due to logging, land conversion for agriculture, overfishing and industrial pollution. This study aims to determine the crab community composition at different sites of the lagoon in relation to vegetation composition and sediment parameters. In addition it investigates if mangrove crabs can be used as bioindicators to describe the environmental state of mangrove forests (tree diversity, degree of logging). It was assumed to find a low crab diversity and species richness and a strong dominance of a single species at highly disturbed forest sites compared to moderately disturbed sites. A stratified, hierarchical design was used to sample the crab fauna at 13 stations distributed over the entire lagoon. Additionally, abiotic parameters and vegetation composition were recorded. In total 6463 crabs were caught belonging to 49 species, 5 superfamilies and 10 families, with Ocypodidae and Sesarmidae being the families of most note. Mean density of adult crabs was 27.7 individuals*m -2 and mean biomass was 12.8 g wet mass*m -2 or 1.3 g ash free dry mass*m -2. Density and biomass varied strongly within and between stations but they where within the range reported for other mangrove forests of the Indo-West-Pacific. Species composition was significantly different between stations. The distribution of facultatively leaf-feeding grapsid crabs was related to vegetation parameters (tree, seedling and undergrowth density), but the occurrence of single crab and tree species was not correlated. The distribution of

  13. Predicting mangrove forest recovery on the southwest coast of Florida following the impact of Hurricane Wilma, October 2005: Chapter 6H in Science and the storms-the USGS response to the hurricanes of 2005

    USGS Publications Warehouse

    Ward, Greg A.; Smith, Thomas J.

    2007-01-01

    The damage to mangrove forests on the west coast of Everglades National Park from Hurricane Wilma in 2005 rivaled that of Hurricane Andrew in 1992. We describe patterns and rates of recovery following Andrew and use these estimates to gage recovery based upon site reconnaissance and forest structural damage considerations in the aftermath of Wilma.

  14. Coastal sediment elevation change following anthropogenic mangrove clearing

    NASA Astrophysics Data System (ADS)

    Hayden, Heather L.; Granek, Elise F.

    2015-11-01

    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.

  15. CTFS/ForestGEO: A global network to monitor forest interactions with a changing climate

    NASA Astrophysics Data System (ADS)

    Anderson-Teixeira, K. J.; Muller-Landau, H.; McMahon, S.; Davies, S. J.

    2013-12-01

    Forests are an influential component of the global carbon cycle and strongly influence Earth's climate. Climate change is altering the dynamics of forests globally, which may result in significant climate feedbacks. Forest responses to climate change entail both short-term ecophysiological responses and longer-term directional shifts in community composition. These short- and long-term responses of forest communities to climate change may be better understood through long-term monitoring of large forest plots globally using standardized methodology. Here, we describe a global network of forest research plots (CTFS/ForestGEO) of utility for understanding forest responses to climate change and consequent feedbacks to the climate system. CTFS/ForestGEO is an international network consisting of 51 sites ranging in size from 2-150 ha (median size: 25 ha) and spanning from 25°S to 52°N latitude. At each site, every individual > 1cm DBH is mapped and identified, and recruitment, growth, and mortality are monitored every 5 years. Additional measurements include aboveground productivity, carbon stocks, soil nutrients, plant functional traits, arthropod and vertebrates monitoring, DNA barcoding, airborne and ground-based LiDAR, micrometeorology, and weather monitoring. Data from this network are useful for understanding how forest ecosystem structure and function respond to spatial and temporal variation in abiotic drivers, parameterizing and evaluating ecosystem and earth system models, aligning airborne and ground-based measurements, and identifying directional changes in forest productivity and composition. For instance, CTFS/ForestGEO data have revealed that solar radiation and night-time temperature are important drivers of aboveground productivity in moist tropical forests; that tropical forests are mixed in terms of productivity and biomass trends over the past couple decades; and that the composition of Panamanian forests has shifted towards more drought

  16. Environmental monitoring and assessment program forest health monitoring quality assurance project plan for detection monitoring project

    SciTech Connect

    Cline, S.P.; Alexander, S.A.; Barnard, J.E.

    1995-05-01

    The Quality Assurance Project Plan (QAP) is written specifically for the Detection Minitoring project of the interagency Forest Health Monitoring (FHM) program. Sections 1 through 3 briefly explain key features of the Environmental Monitoring and Assessment Program (EMAP), the FHM program, and their interrelationship, respectively. Section 4 describes the general quality assurance (QA) requirements for the FHM Detection Monitoring project. Section 5 contains the separate QAPs for each forest condition indicator: site condition and tree growth and regeneration, tree crown condition, tree damage assessment, photosynthetically active radiation (PAR), vegetation structure, ozone bioindicator plants, and lichen communities.

  17. The application of satellite data for the quantification of mangrove loss and coastal management in the Godavari estuary, East Coast of India.

    PubMed

    Satapathy, D R; Krupadam, R J; Kumar, L Pawan; Wate, S R

    2007-11-01

    The mangrove formations of Godavari estuary are due to silting over many centuries. The estuary covers an area of 62,000 ha of which dense Coringa mangrove forest spread in 6,600 ha. Satellite sensor data was used to detect change in the mangrove cover for a period of 12 years (1992-2004). It was found that an area of about 1,250 ha of mangroves was destroyed by anthropogenic interference like aquaculture, and tree felling etc. It was found that mangrove's spectral response/digital number (DN) value is much lower than non-mangrove vegetation such as plantation and paddy fields in SWIR band. By taking this as an advantage, spectral data was utilized for clear demarcation of mangroves from nearby paddy fields and other vegetation. Simpson's diversity index, which is a measure of biodiversity, was found to be 0.09, showing mangroves dominance. Ecological parameters like mud-flats/swamps, mangrove cover alterations, and biodiversity status are studied in detail for a period of 12 years. The increase in mangrove front towards coast was delineated using remote sensing data. The major advantages of remote sensing data is monitoring of change periodically. The combination of moderate and high-resolution data provided detailed coastal land use maps for implementing coastal regulation measures. The classification accuracy has been achieved is 90%. Overall, simple and viable measures are suggested based on multi-spectral data to sustain this sensitive coastal ecology. PMID:17345010

  18. Regional processes in mangrove ecosystems: Spatial scaling relationships, biomass, and turnover rates following catastrophic disturbance

    USGS Publications Warehouse

    Ward, G.A.; Smith, T. J.; Whelan, K.R.T.; Doyle, T.W.

    2006-01-01

    Physiological processes and local-scale structural dynamics of mangroves are relatively well studied. Regional-scale processes, however, are not as well understood. Here we provide long-term data on trends in structure and forest turnover at a large scale, following hurricane damage in mangrove ecosystems of South Florida, U.S.A. Twelve mangrove vegetation plots were monitored at periodic intervals, between October 1992 and March 2005. Mangrove forests of this region are defined by a -1.5 scaling relationship between mean stem diameter and stem density, mirroring self-thinning theory for mono-specific stands. This relationship is reflected in tree size frequency scaling exponents which, through time, have exhibited trends toward a community average that is indicative of full spatial resource utilization. These trends, together with an asymptotic standing biomass accumulation, indicate that coastal mangrove ecosystems do adhere to size-structured organizing principles as described for upland tree communities. Regenerative dynamics are different between areas inside and outside of the primary wind-path of Hurricane Andrew which occurred in 1992. Forest dynamic turnover rates, however, are steady through time. This suggests that ecological, more-so than structural factors, control forest productivity. In agreement, the relative mean rate of biomass growth exhibits an inverse relationship with the seasonal range of porewater salinities. The ecosystem average in forest scaling relationships may provide a useful investigative tool of mangrove community biomass relationships, as well as offer a robust indicator of general ecosystem health for use in mangrove forest ecosystem management and restoration. ?? Springer 2006.

  19. Mangrove forest against dyke-break-induced tsunami on rapidly subsiding coasts

    NASA Astrophysics Data System (ADS)

    Takagi, Hiroshi; Mikami, Takahito; Fujii, Daisuke; Esteban, Miguel; Kurobe, Shota

    2016-07-01

    Thin coastal dykes typically found in developing countries may suddenly collapse due to rapid land subsidence, material ageing, sea-level rise, high wave attack, earthquakes, landslides, or a collision with vessels. Such a failure could trigger dam-break tsunami-type flooding, or "dyke-break-induced tsunami", a possibility which has so far been overlooked in the field of coastal disaster science and management. To analyse the potential consequences of one such flooding event caused by a dyke failure, a hydrodynamic model was constructed based on the authors' field surveys of a vulnerable coastal location in Jakarta, Indonesia. In a 2 m land subsidence scenario - which is expected to take place in the study area after only about 10-20 years - the model results show that the floodwaters rapidly rise to a height of nearly 3 m, resembling the flooding pattern of earthquake-induced tsunamis. The depth-velocity product criterion suggests that many of the narrow pedestrian paths behind the dyke could experience strong flows, which are far greater than the safe limits that would allow pedestrian evacuation. A couple of alternative scenarios were also considered to investigate how such flood impacts could be mitigated by creating a mangrove belt in front of the dyke as an additional safety measure. The dyke-break-induced tsunamis, which in many areas are far more likely than regular earthquake tsunamis, cannot be overlooked and thus should be considered in disaster management and urban planning along the coasts of many developing countries.

  20. Mangrove postcard

    USGS Publications Warehouse

    Ball, Lianne C.

    2016-07-14

    Mangrove ecosystems protect vulnerable coastlines from storm effects, recycle nutrients, stabilize shorelines, improve water quality, and provide habitat for commercial and recreational fish species as well as for threatened and endangered wildlife. U.S. Geological Survey scientists conduct research on mangrove ecosystems to provide reliable scientific information about their ecology, productivity, hydrological processes, carbon storage stress response, and restoration success. The Mangrove Science Network is a collaboration of USGS scientists focused on working with natural resource managers to develop and conduct research to inform decisions on mangrove management and restoration. Information about the Mangrove Science Network can be found at: http://www.usgs.gov/ecosystems/environments/mangroves.html.

  1. Modeling hurricane effects on mangrove ecosystems

    USGS Publications Warehouse

    Doyle, Thomas W.

    1997-01-01

    Mangrove ecosystems are at their most northern limit along the coastline of Florida and in isolated areas of the gulf coast in Louisiana and Texas. Mangroves are marine-based forests that have adapted to colonize and persist in salty intertidal waters. Three species of mangrove trees are common to the United States, black mangrove (Avicennia germinans), white mangrove (Laguncularia racemosa), and red mangrove (Rhizophora mangle). Mangroves are highly productive ecosystems and provide valuable habitat for fisheries and shorebirds. They are susceptible to lightning and hurricane disturbance, both of which occur frequently in south Florida. Climate change studies predict that, while these storms may not become more frequent, they may become more intense with warming sea temperatures. Sea-level rise alone has the potential for increasing the severity of storm surge, particularly in areas where coastal habitats and barrier shorelines are rapidly deteriorating. Given this possibility, U.S. Geological Survey researchers modeled the impact of hurricanes on south Florida mangrove communities.

  2. The Significance of Forest Monitoring Programmes: the Finnish Perspective

    NASA Astrophysics Data System (ADS)

    Merila, P.; Derome, J.; Lindgren, M.

    2007-12-01

    Finland has been participating in the ICP Forests programme (the International Co-operative Programme on the Assessment and Monitoring of Air Pollution Effects on Forests) based on international agreements on the long- range transportation of air pollutants (LRTAP) and other associated monitoring programmes (e.g. Forest Focus, ICP Integrated Monitoring, ICP Vegetation) since 1985. The knowledge gained during the years has greatly increased our understanding of the overall condition of our forests and the factors affecting forest condition, the processes underlying forest ecosystem functioning, and the potential threats to our forests posed by human activities, both at home and abroad. The success of the monitoring activities in Finland is largely based on the experience gained during the early 1980's with our own national acidification project and, during the late 1980's and early 1990"s, in a number of regional monitoring projects. Finland's membership of the European Union (entry in 1996) has enabled us to further develop the infrastructure and coverage of both our extensive and intensive level networks. This broadening of our ecological understanding and development of international collaboration are now providing us with an invaluable basis for addressing the new monitoring challenges (biodiversity, climate change). The results gained in our monitoring activities clearly demonstrate the value of long-term monitoring programmes. The main results have been regularly reported both at the European (e.g. http://www.icp- forests.org/Reports.htm) and national level (e.g. http://www.metla.fi/julkaisut/workingpapers/2007/mwp045- en.htm). However, the datasets have not been intensively explored and exploited, and few of the important methodological and ecological findings have been published in peer-reviewed scientific journals. This has, understandably, not been the first priority of the international monitoring programmes. A number of the intensive forest monitoring

  3. Satellite Data Aid Monitoring of Nation's Forests

    NASA Technical Reports Server (NTRS)

    2014-01-01

    The USDA Forest Service’s Asheville, North Carolina-based Eastern Forest Environmental Threat Assessment Center and Prineville, Oregon-based Western Wildlands Environmental Threat Assessment Center partnered with Stennis Space Center and other agencies to create an early warning system to identify, characterize, and track disturbances from potential forest threats. The result was ForWarn, which is now being used by federal and state forest and natural resource managers.

  4. Mangrove Forest Cover Extraction of the Coastal Areas of Negros Occidental, Western Visayas, Philippines Using LIDAR Data

    NASA Astrophysics Data System (ADS)

    Pada, A. V.; Silapan, J.; Cabanlit, M. A.; Campomanes, F.; Garcia, J. J.

    2016-06-01

    Mangroves have a lot of economic and ecological advantages which include coastal protection, habitat for wildlife, fisheries and forestry products. Determination of the extent of mangrove patches in the coastal areas of the Philippines is therefore important especially in resource conservation, protection and management. This starts with a well-defined and accurate map. LiDARwas used in the mangrove extraction in the different coastal areas of Negros Occidental in Western Visayas, Philippines. Total coastal study area is 1,082.55 km² for the 14 municipalities/ cities processed. Derivatives that were used in the extraction include, DSM, DTM, Hillshade, Intensity, Number of Returns and PCA. The RGB bands of the Orthographic photographs taken at the same time with the LiDAR data were also used as one of the layers during the processing. NDVI, GRVI and Hillshade using Canny Edge Layer were derived as well to produce an enhanced segmentation. Training and Validation points were collected through field validation and visual inspection using Stratified Random Sampling. The points were then used to feed the Support Vector Machine (SVM) based on tall structures. Only four classes were used, namely, Built-up, Mangroves, Other Trees and Sugarcane. Buffering and contextual editing were incorporated to reclassify the extracted mangroves. Overall accuracy assessment is at 98.73% (KIA of 98.24%) while overall accuracy assessment for Mangroves only is at 98.00%. Using this workflow, mangroves can already be extracted in a large-scale level with acceptable overall accuracy assessments.

  5. CTFS-ForestGEO: a worldwide network monitoring forests in an era of global change.

    PubMed

    Anderson-Teixeira, Kristina J; Davies, Stuart J; Bennett, Amy C; Gonzalez-Akre, Erika B; Muller-Landau, Helene C; Wright, S Joseph; Abu Salim, Kamariah; Almeyda Zambrano, Angélica M; Alonso, Alfonso; Baltzer, Jennifer L; Basset, Yves; Bourg, Norman A; Broadbent, Eben N; Brockelman, Warren Y; Bunyavejchewin, Sarayudh; Burslem, David F R P; Butt, Nathalie; Cao, Min; Cardenas, Dairon; Chuyong, George B; Clay, Keith; Cordell, Susan; Dattaraja, Handanakere S; Deng, Xiaobao; Detto, Matteo; Du, Xiaojun; Duque, Alvaro; Erikson, David L; Ewango, Corneille E N; Fischer, Gunter A; Fletcher, Christine; Foster, Robin B; Giardina, Christian P; Gilbert, Gregory S; Gunatilleke, Nimal; Gunatilleke, Savitri; Hao, Zhanqing; Hargrove, William W; Hart, Terese B; Hau, Billy C H; He, Fangliang; Hoffman, Forrest M; Howe, Robert W; Hubbell, Stephen P; Inman-Narahari, Faith M; Jansen, Patrick A; Jiang, Mingxi; Johnson, Daniel J; Kanzaki, Mamoru; Kassim, Abdul Rahman; Kenfack, David; Kibet, Staline; Kinnaird, Margaret F; Korte, Lisa; Kral, Kamil; Kumar, Jitendra; Larson, Andrew J; Li, Yide; Li, Xiankun; Liu, Shirong; Lum, Shawn K Y; Lutz, James A; Ma, Keping; Maddalena, Damian M; Makana, Jean-Remy; Malhi, Yadvinder; Marthews, Toby; Mat Serudin, Rafizah; McMahon, Sean M; McShea, William J; Memiaghe, Hervé R; Mi, Xiangcheng; Mizuno, Takashi; Morecroft, Michael; Myers, Jonathan A; Novotny, Vojtech; de Oliveira, Alexandre A; Ong, Perry S; Orwig, David A; Ostertag, Rebecca; den Ouden, Jan; Parker, Geoffrey G; Phillips, Richard P; Sack, Lawren; Sainge, Moses N; Sang, Weiguo; Sri-Ngernyuang, Kriangsak; Sukumar, Raman; Sun, I-Fang; Sungpalee, Witchaphart; Suresh, Hebbalalu Sathyanarayana; Tan, Sylvester; Thomas, Sean C; Thomas, Duncan W; Thompson, Jill; Turner, Benjamin L; Uriarte, Maria; Valencia, Renato; Vallejo, Marta I; Vicentini, Alberto; Vrška, Tomáš; Wang, Xihua; Wang, Xugao; Weiblen, George; Wolf, Amy; Xu, Han; Yap, Sandra; Zimmerman, Jess

    2015-02-01

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses to global change. Within very large plots (median size 25 ha), all stems ≥ 1 cm diameter are identified to species, mapped, and regularly recensused according to standardized protocols. CTFS-ForestGEO spans 25 °S-61 °N latitude, is generally representative of the range of bioclimatic, edaphic, and topographic conditions experienced by forests worldwide, and is the only forest monitoring network that applies a standardized protocol to each of the world's major forest biomes. Supplementary standardized measurements at subsets of the sites provide additional information on plants, animals, and ecosystem and environmental variables. CTFS-ForestGEO sites are experiencing multifaceted anthropogenic global change pressures including warming (average 0.61 °C), changes in precipitation (up to ± 30% change), atmospheric deposition of nitrogen and sulfur compounds (up to 3.8 g N m(-2) yr(-1) and 3.1 g S m(-2) yr(-1)), and forest fragmentation in the surrounding landscape (up to 88% reduced tree cover within 5 km). The broad suite of measurements made at CTFS-ForestGEO sites makes it possible to investigate the complex ways in which global change is impacting forest dynamics. Ongoing research across the CTFS-ForestGEO network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in an era of global change.

  6. CTFS-ForestGEO: a worldwide network monitoring forests in an era of global change.

    PubMed

    Anderson-Teixeira, Kristina J; Davies, Stuart J; Bennett, Amy C; Gonzalez-Akre, Erika B; Muller-Landau, Helene C; Wright, S Joseph; Abu Salim, Kamariah; Almeyda Zambrano, Angélica M; Alonso, Alfonso; Baltzer, Jennifer L; Basset, Yves; Bourg, Norman A; Broadbent, Eben N; Brockelman, Warren Y; Bunyavejchewin, Sarayudh; Burslem, David F R P; Butt, Nathalie; Cao, Min; Cardenas, Dairon; Chuyong, George B; Clay, Keith; Cordell, Susan; Dattaraja, Handanakere S; Deng, Xiaobao; Detto, Matteo; Du, Xiaojun; Duque, Alvaro; Erikson, David L; Ewango, Corneille E N; Fischer, Gunter A; Fletcher, Christine; Foster, Robin B; Giardina, Christian P; Gilbert, Gregory S; Gunatilleke, Nimal; Gunatilleke, Savitri; Hao, Zhanqing; Hargrove, William W; Hart, Terese B; Hau, Billy C H; He, Fangliang; Hoffman, Forrest M; Howe, Robert W; Hubbell, Stephen P; Inman-Narahari, Faith M; Jansen, Patrick A; Jiang, Mingxi; Johnson, Daniel J; Kanzaki, Mamoru; Kassim, Abdul Rahman; Kenfack, David; Kibet, Staline; Kinnaird, Margaret F; Korte, Lisa; Kral, Kamil; Kumar, Jitendra; Larson, Andrew J; Li, Yide; Li, Xiankun; Liu, Shirong; Lum, Shawn K Y; Lutz, James A; Ma, Keping; Maddalena, Damian M; Makana, Jean-Remy; Malhi, Yadvinder; Marthews, Toby; Mat Serudin, Rafizah; McMahon, Sean M; McShea, William J; Memiaghe, Hervé R; Mi, Xiangcheng; Mizuno, Takashi; Morecroft, Michael; Myers, Jonathan A; Novotny, Vojtech; de Oliveira, Alexandre A; Ong, Perry S; Orwig, David A; Ostertag, Rebecca; den Ouden, Jan; Parker, Geoffrey G; Phillips, Richard P; Sack, Lawren; Sainge, Moses N; Sang, Weiguo; Sri-Ngernyuang, Kriangsak; Sukumar, Raman; Sun, I-Fang; Sungpalee, Witchaphart; Suresh, Hebbalalu Sathyanarayana; Tan, Sylvester; Thomas, Sean C; Thomas, Duncan W; Thompson, Jill; Turner, Benjamin L; Uriarte, Maria; Valencia, Renato; Vallejo, Marta I; Vicentini, Alberto; Vrška, Tomáš; Wang, Xihua; Wang, Xugao; Weiblen, George; Wolf, Amy; Xu, Han; Yap, Sandra; Zimmerman, Jess

    2015-02-01

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses to global change. Within very large plots (median size 25 ha), all stems ≥ 1 cm diameter are identified to species, mapped, and regularly recensused according to standardized protocols. CTFS-ForestGEO spans 25 °S-61 °N latitude, is generally representative of the range of bioclimatic, edaphic, and topographic conditions experienced by forests worldwide, and is the only forest monitoring network that applies a standardized protocol to each of the world's major forest biomes. Supplementary standardized measurements at subsets of the sites provide additional information on plants, animals, and ecosystem and environmental variables. CTFS-ForestGEO sites are experiencing multifaceted anthropogenic global change pressures including warming (average 0.61 °C), changes in precipitation (up to ± 30% change), atmospheric deposition of nitrogen and sulfur compounds (up to 3.8 g N m(-2) yr(-1) and 3.1 g S m(-2) yr(-1)), and forest fragmentation in the surrounding landscape (up to 88% reduced tree cover within 5 km). The broad suite of measurements made at CTFS-ForestGEO sites makes it possible to investigate the complex ways in which global change is impacting forest dynamics. Ongoing research across the CTFS-ForestGEO network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in an era of global change. PMID:25258024

  7. Impact of typhoon disturbance on the diversity of key ecosystem engineers in a monoculture mangrove forest plantation, Can Gio Biosphere Reserve, Vietnam

    NASA Astrophysics Data System (ADS)

    Diele, K.; Tran Ngoc, D. M.; Geist, S. J.; Meyer, F. W.; Pham, Q. H.; Saint-Paul, U.; Tran, T.; Berger, U.

    2013-11-01

    Mangrove crabs as key ecosystem engineers may play an important role in the recovery process of storm-damaged forests. Yet, their response to storm disturbance is largely unknown. Here we compare the ground-dwelling brachyuran crab community of intact mangrove stands with that of typhoon gaps having experienced 100% tree mortality. Field work was conducted in two adjacent areas in Can Gio Biosphere Reserve, southern Vietnam. In each area, an 18-20 yr old monoculture Rhizophora apiculata stand served as control and was compared with typhoon gaps where downed stems had been removed or left on-site. The gaps were 14 and 20 months old when studied in the dry and rainy season 2008, respectively. Time-based sampling of ground-dwelling crabs with hand or shovel was conducted by 4 persons inside 100 m2 plots for 30 min (7 replicate plots per area, treatment and month). Abiotic (sediment pH, salinity, temperature, grain size, water content, carbon and nitrogen content), and biotic measures (e.g. canopy coverage, woody debris, number of trees, leaf litter) were also taken. Despite complete canopy loss, total crab abundance has not changed significantly (in contrast to biomass) and all 12 species found in the forest were also found in the gaps, demonstrating their robustness. Another 9 gap-exclusive species were recorded and average species number and Shannon diversity were thus higher in the gaps. Perisesarma eumolpe was the most abundant species, both in the forest and in the gaps, and a shift from sesarmids (typical forest species) to ocypodids (generally more prominent in open areas) has not occurred. The persistence of litter-feeding sesarmid crabs prior to the re-establishment of a mangrove canopy is likely to depend on the availability of woody debris on the ground of the gaps, fuelling a mangrove detritus based food web, rather than one based on microphytobenthos and deposit-feeding ocypodids. The presence of burrowing crabs in the gaps suggests that important

  8. Hurricane Wilma's impact on overall soil elevation and zones within the soil profile in a mangrove forest

    USGS Publications Warehouse

    Whelan, K.R.T.; Smith, T. J.; Anderson, G.H.; Ouellette, M.L.

    2009-01-01

    Soil elevation affects tidal inundation period, inundation frequency, and overall hydroperiod, all of which are important ecological factors affecting species recruitment, composition, and survival in wetlands. Hurricanes can dramatically affect a site's soil elevation. We assessed the impact of Hurricane Wilma (2005) on soil elevation at a mangrove forest location along the Shark River in Everglades National Park, Florida, USA. Using multiple depth surface elevation tables (SETs) and marker horizons we measured soil accretion, erosion, and soil elevation. We partitioned the effect of Hurricane Wilma's storm deposit into four constituent soil zones: surface (accretion) zone, shallow zone (0–0.35 m), middle zone (0.35–4 m), and deep zone (4–6 m). We report expansion and contraction of each soil zone. Hurricane Wilma deposited 37.0 (± 3.0 SE) mm of material; however, the absolute soil elevation change was + 42.8 mm due to expansion in the shallow soil zone. One year post-hurricane, the soil profile had lost 10.0 mm in soil elevation, with 8.5 mm of the loss due to erosion. The remaining soil elevation loss was due to compaction from shallow subsidence. We found prolific growth of new fine rootlets (209 ± 34 SE g m−2) in the storm deposited material suggesting that deposits may become more stable in the near future (i.e., erosion rate will decrease). Surficial erosion and belowground processes both played an important role in determining the overall soil elevation. Expansion and contraction in the shallow soil zone may be due to hydrology, and in the middle and bottom soil zones due to shallow subsidence. Findings thus far indicate that soil elevation has made substantial gains compared to site specific relative sea-level rise, but data trends suggest that belowground processes, which differ by soil zone, may come to dominate the long term ecological impact of storm deposit.

  9. Streptomyces gilvigriseus sp. nov., a novel actinobacterium isolated from mangrove forest soil.

    PubMed

    Ser, Hooi-Leng; Zainal, Nurullhudda; Palanisamy, Uma Devi; Goh, Bey-Hing; Yin, Wai-Fong; Chan, Kok-Gan; Lee, Learn-Han

    2015-06-01

    A novel Streptomyces, strain MUSC 26(T), was isolated from mangrove soil at Tanjung Lumpur, Malaysia. The bacterium was observed to be Gram-positive and to form grayish yellow aerial and substrate mycelium on ISP 7 agar. A polyphasic approach was used to study the taxonomy of strain MUSC 26(T), which shows a range of phylogenetic and chemotaxonomic properties consistent with those of the members of the genus Streptomyces. The cell wall peptidoglycan was determined to contain LL-diaminopimelic acid. The predominant menaquinones were identified as MK-9 (H8) and MK-9(H6). The polar lipids detected were identified as diphosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylmethylethanolamine and hydroxyphosphatidylmethylethanolamine. The predominant cellular fatty acids (>10.0 %) were identified as anteiso-C15:0 (31.4 %), iso-C16:0 (16.3 %), iso-C15:0 (13.9 %) and anteiso-C17:0 (12.6 %). The cell wall sugars were found to be galactose, glucose, mannose, ribose and rhamnose. These results suggest that MUSC 26(T) should be placed within the genus Streptomyces. Phylogenetic analysis indicated that closely related strains include Streptomyces qinglanensis 172205(T) (96.5 % sequence similarity), S. sodiiphilus YIM 80305(T) (96.5 %) and S. rimosus subsp. rimosus ATCC 10970(T) (96.4 %). DNA-DNA relatedness values between MUSC 26(T) and closely related type strains ranged from 17.0 ± 2.2 to 33.2 ± 5.3 %. Comparison of BOX-PCR fingerprints indicated MUSC 26(T) presents a unique DNA profile. The DNA G+C content was determined to be 74.6 mol%. Based on this polyphasic study of MUSC 26(T), it is concluded that this strain represents a novel species, for which the name Streptomyces gilvigriseus sp. nov. is proposed. The type strain is MUSC 26(T) (=DSMZ 42173(T) = MCCC 1K00504(T)). PMID:25863667

  10. Monitoring the health of a forest: A Canadian approach.

    PubMed

    Addison, P A

    1989-04-01

    In Canada, acid rain is the generic term encompassing all forms of air pollution - wet and dry deposition, gaseous pollutant concentrations, and airborne particulates. It was because these pollutants, alone or in combination, may directly or indirectly affect the heath of Canada's forests, that in 1984, the Canadian Forestry Service initiated a national forest monitoring program (Acid Rain National Early Warning System or ARNEWS).Research studies on pollutant effects of the past 15-20 years have demonstrated that it is not possible to define specific symptoms of acid rain or mixtures of pollutants on native tree species or specific responses of the forest ecosystem. Consequently, ARNEWS monitored incipient acid rain effects by determining the forest's state of health rather than by concentrating on specific pollutant responses.The detection system entails experienced insect and disease survey forest rangers assessing both specific plots and the forest as a whole for extraordinary forest damage. The techniques used include mensurational and symptomatological measurements as well as evaluation of stands for damage from natural and anthropogenic causes. Critical also to the system was the capability of the Canadian Forestry Service to support the detection system with research staff who could carry out studies to explain any abnormalities in forest condition detected during the annual surveys. The ultimate outcome of the monitoring system if unexplained forest damage is detected is a research project on possible causes.

  11. Forest genetic monitoring: an overview of concepts and definitions.

    PubMed

    Fussi, Barbara; Westergren, Marjana; Aravanopoulos, Filippos; Baier, Roland; Kavaliauskas, Darius; Finzgar, Domen; Alizoti, Paraskevi; Bozic, Gregor; Avramidou, Evangelia; Konnert, Monika; Kraigher, Hojka

    2016-08-01

    Safeguarding sustainability of forest ecosystems with their habitat variability and all their functions is of highest priority. Therefore, the long-term adaptability of forest ecosystems to a changing environment must be secured, e.g., through sustainable forest management. High adaptability is based on biological variation starting at the genetic level. Thus, the ultimate goal of the Convention on Biological Diversity (CBD) to halt the ongoing erosion of biological variation is of utmost importance for forest ecosystem functioning and sustainability. Monitoring of biological diversity over time is needed to detect changes that threaten these biological resources. Genetic variation, as an integral part of biological diversity, needs special attention, and its monitoring can ensure its effective conservation. We compare forest genetic monitoring to other biodiversity monitoring concepts. Forest genetic monitoring (FGM) enables early detection of potentially harmful changes of forest adaptability before these appear at higher biodiversity levels (e.g., species or ecosystem diversity) and can improve the sustainability of applied forest management practices and direct further research. Theoretical genetic monitoring concepts developed up to now need to be evaluated before being implemented on a national and international scale. This article provides an overview of FGM concepts and definitions, discusses their advantages and disadvantages, and provides a flow chart of the steps needed for the optimization and implementation of FGM. FGM is an important module of biodiversity monitoring, and we define an effective FGM scheme as consisting of an assessment of a forest population's capacity to survive, reproduce, and persist under rapid environmental changes on a long-term scale.

  12. Forest genetic monitoring: an overview of concepts and definitions.

    PubMed

    Fussi, Barbara; Westergren, Marjana; Aravanopoulos, Filippos; Baier, Roland; Kavaliauskas, Darius; Finzgar, Domen; Alizoti, Paraskevi; Bozic, Gregor; Avramidou, Evangelia; Konnert, Monika; Kraigher, Hojka

    2016-08-01

    Safeguarding sustainability of forest ecosystems with their habitat variability and all their functions is of highest priority. Therefore, the long-term adaptability of forest ecosystems to a changing environment must be secured, e.g., through sustainable forest management. High adaptability is based on biological variation starting at the genetic level. Thus, the ultimate goal of the Convention on Biological Diversity (CBD) to halt the ongoing erosion of biological variation is of utmost importance for forest ecosystem functioning and sustainability. Monitoring of biological diversity over time is needed to detect changes that threaten these biological resources. Genetic variation, as an integral part of biological diversity, needs special attention, and its monitoring can ensure its effective conservation. We compare forest genetic monitoring to other biodiversity monitoring concepts. Forest genetic monitoring (FGM) enables early detection of potentially harmful changes of forest adaptability before these appear at higher biodiversity levels (e.g., species or ecosystem diversity) and can improve the sustainability of applied forest management practices and direct further research. Theoretical genetic monitoring concepts developed up to now need to be evaluated before being implemented on a national and international scale. This article provides an overview of FGM concepts and definitions, discusses their advantages and disadvantages, and provides a flow chart of the steps needed for the optimization and implementation of FGM. FGM is an important module of biodiversity monitoring, and we define an effective FGM scheme as consisting of an assessment of a forest population's capacity to survive, reproduce, and persist under rapid environmental changes on a long-term scale. PMID:27473107

  13. [Sedimentological Implications of the change in the coverage of mangrove forest in Boca Zacate, Térraba-Sierpa National Wetlands, Costa Rica].

    PubMed

    Silva Benavides, Ana Margarita; Picado Barboza, Jorge; Mora Rodríguez, Fernando; González Gairaud, Carmen

    2015-09-01

    In the last sixty years many geomorphological changes have occurred in Costa Rica's Térraba-Sierpe National Wetlands. Changes in coastal geomorphology are generally associated with erosion or accretion of sediment, which has led to the removal of sections of mangrove forests or sediment banks colonized by mangroves. The aim of this study was to analyze sedimentation as a leading process in the dynamics of coastal morphology and its implications for mangrove forest cover in the Boca Zacate area of Térraba-Sierpe wetlands. The study was conducted in the sectors of Bocón, Brujo and Coco Island in Boca Zacate, from 2008 to 2013. The research was based on a multi-temporal analysis of coastal morphology using aerial photographs from the years 1948, 1960, 1974, 1978, 1984, 1992 and 2011. The following measurements were also performed: monthly sedimentation rate (g/cm2/day), and granulometric composition and content of chemical elements in the sediments of the study area. These last two measurements were performed once each in the dry and rainy seasons during the years of study. The results indicated that over the past 60 years, Boca Zacate has witnessed a process of sustained erosion; from 1948 through 2001, losing 10.6 % of its land and approximately 8.9 % of its forest cover. It has also experienced accretion in the area of Coco Island. The Brujo sector showed the highest sedimentation rate and the Camibar estuary, the lowest. The dominant type of sediment in all study sites was sand, followed by clay and silt. The most widespread chemical elements (mg/L) included magnesium, calcium and potassium; others, such as manganese, iron, aluminum, phosphorus, zinc and copper, were measured in smaller amounts. Transport, composition and quantity of sediment in Boca Zacate are crucial to the changes that have occurred on the coastal area of La Boca, where the presence of dead trees was evident. This geomorphological analysis holds great importance for future guidelines and

  14. [Sedimentological Implications of the change in the coverage of mangrove forest in Boca Zacate, Térraba-Sierpa National Wetlands, Costa Rica].

    PubMed

    Silva Benavides, Ana Margarita; Picado Barboza, Jorge; Mora Rodríguez, Fernando; González Gairaud, Carmen

    2015-09-01

    In the last sixty years many geomorphological changes have occurred in Costa Rica's Térraba-Sierpe National Wetlands. Changes in coastal geomorphology are generally associated with erosion or accretion of sediment, which has led to the removal of sections of mangrove forests or sediment banks colonized by mangroves. The aim of this study was to analyze sedimentation as a leading process in the dynamics of coastal morphology and its implications for mangrove forest cover in the Boca Zacate area of Térraba-Sierpe wetlands. The study was conducted in the sectors of Bocón, Brujo and Coco Island in Boca Zacate, from 2008 to 2013. The research was based on a multi-temporal analysis of coastal morphology using aerial photographs from the years 1948, 1960, 1974, 1978, 1984, 1992 and 2011. The following measurements were also performed: monthly sedimentation rate (g/cm2/day), and granulometric composition and content of chemical elements in the sediments of the study area. These last two measurements were performed once each in the dry and rainy seasons during the years of study. The results indicated that over the past 60 years, Boca Zacate has witnessed a process of sustained erosion; from 1948 through 2001, losing 10.6 % of its land and approximately 8.9 % of its forest cover. It has also experienced accretion in the area of Coco Island. The Brujo sector showed the highest sedimentation rate and the Camibar estuary, the lowest. The dominant type of sediment in all study sites was sand, followed by clay and silt. The most widespread chemical elements (mg/L) included magnesium, calcium and potassium; others, such as manganese, iron, aluminum, phosphorus, zinc and copper, were measured in smaller amounts. Transport, composition and quantity of sediment in Boca Zacate are crucial to the changes that have occurred on the coastal area of La Boca, where the presence of dead trees was evident. This geomorphological analysis holds great importance for future guidelines and

  15. [Carbon storage and carbon sink of mangrove wetland: research progress].

    PubMed

    Zhang, Li; Guo, Zhi-hua; Li, Zhi-yong

    2013-04-01

    Mangrove forest is a special wetland forest growing in the inter-tidal zone of tropical and subtropical regions, playing important roles in windbreak, promoting silt sedimentation, resisting extreme events such as cyclones and tsunamis, and protecting coastline, etc. The total area of global mangrove forests is about 152000 km2, only accounting for 0. 4% of all forest area. There are about 230 km2 mangrove forests in China. The mangrove forests in the tropics have an average carbon storage as high as 1023 Mg hm-2, and the global mangrove forests can sequestrate about 0. 18-0. 228 Pg C a-1. In addition to plant species composition, a variety of factors such as air temperature, seawater temperature and salinity, soil physical and chemical properties, atmospheric CO2 concentration, and human activities have significant effects on the carbon storage and sink ability of mangrove forests. Many approaches based onfield measurements, including allometric equations, remote sensing, and model simulation, are applied to quantify the carbon storage and sink ability of mangrove forest wetland. To study the carbon storage and sink ability of mangrove wetland can promote the further understanding of the carbon cycle of mangrove wetland and related controlling mechanisms, being of significance for the protection and rational utilization of mangrove wetland.

  16. [Carbon storage and carbon sink of mangrove wetland: research progress].

    PubMed

    Zhang, Li; Guo, Zhi-hua; Li, Zhi-yong

    2013-04-01

    Mangrove forest is a special wetland forest growing in the inter-tidal zone of tropical and subtropical regions, playing important roles in windbreak, promoting silt sedimentation, resisting extreme events such as cyclones and tsunamis, and protecting coastline, etc. The total area of global mangrove forests is about 152000 km2, only accounting for 0. 4% of all forest area. There are about 230 km2 mangrove forests in China. The mangrove forests in the tropics have an average carbon storage as high as 1023 Mg hm-2, and the global mangrove forests can sequestrate about 0. 18-0. 228 Pg C a-1. In addition to plant species composition, a variety of factors such as air temperature, seawater temperature and salinity, soil physical and chemical properties, atmospheric CO2 concentration, and human activities have significant effects on the carbon storage and sink ability of mangrove forests. Many approaches based onfield measurements, including allometric equations, remote sensing, and model simulation, are applied to quantify the carbon storage and sink ability of mangrove forest wetland. To study the carbon storage and sink ability of mangrove wetland can promote the further understanding of the carbon cycle of mangrove wetland and related controlling mechanisms, being of significance for the protection and rational utilization of mangrove wetland. PMID:23898678

  17. Hyperspectral Indices for Retrieval of Chlorophyll and Nitrogen in Mangroves Using SLC and HYMAP

    NASA Astrophysics Data System (ADS)

    Fauzi, A.; Schlerf, M.; Skidmore, A.; van Gils, H.; Heitkonig, I. M.

    2011-12-01

    Coastal ecosystems, such as mangroves, pose a challenge for chlorophyll (CHL) and nitrogen (N) estimation using Hyperspectral. Mangroves have unique characteristics such as high humidity, wet soils (mud), water logged, and roots on the mangrove floors that provide strong influence to mangrove canopy spectra. This study aims to find optimum Hyperspectral indices for the estimation of CHL and N concentrations at canopy level using HYMAP data of mangrove forests. The common vegetation indices such as SR, NDVI, PVI, TSAVI, and OVI were applied on original spectra as well as first derivative spectra (using the Savitsky and Golay method). The first method was calculating the best indices to estimate CHL using radiative transfer model, SLC (soil-leaf-canopy). The results were tested to HYMAP data. The second method was calculating the best indices to estimate CHL and N from the HYMAP data which then tested to SLC. The first method provides disagreement between indices determined using SLC and applied to HYMAP data. The second method provides good agreement between indices determined using HYMAP data and applied to SLC. The best indices: for CHL estimation dSR=dρ544/dρ1736, for N estimation PVI = ρ514 - 0.9*ρ676 - 0.1/1.3454. Information on CHL and N concentrations of mangroves are important to monitor nutrient enrichment of coastal zone and their effects to mangrove ecosystem.

  18. Microhabitat associations of a semi-terrestrial fish, Kryptolebias marmoratus (Poey 1880) in a mosquito-ditched mangrove forest, west-central Florida

    USGS Publications Warehouse

    Richards, Travis M.; Krebs, Justin M.; McIvor, Carole C.

    2011-01-01

    Mangrove rivulus (Kryptolebias marmoratus) is one of the few species of fish that is semi-terrestrial and able to use exposed intertidal and potentially supratidal habitats for prolonged periods of time. Based on previous work demonstrating frequent use of subterranean crab burrows as well as damp leaf litter and logs, we examined the microhabitat associations of rivulus in a mosquito-ditched mangrove forest on the Gulf coast of Florida near the northern limit of its distribution. We captured 161 rivulus on 20 dates between late April and mid-December 2007 using trench traps. Fish ranged in size from 7 to 35 mm SL. Peak abundance in mid-summer coincided with recruitment of a new year-class. The three study sites occurred within 0.5 km of one another, and experienced similar water temperatures and salinities. Nevertheless, they differed in their degree of tidal inundation, standing stock of leaf litter, and density of entrances to fiddler crab burrows. We consistently observed the highest mean catches of rivulus away from permanent subtidal waters of mosquito ditches, at intermediate relative elevations, and where leaf litter was locally abundant. Density of entrances to crab burrows was apparently unrelated to rivulus distribution or abundance in these forests.

  19. Global change impacts on mangrove ecosystems

    USGS Publications Warehouse

    McKee, Karen L.

    2004-01-01

    Mangroves are tropical/subtropical communities of primarily tree species that grow in the intertidal zone. These tidal forests are important coastal ecosystems that are valued for a variety of ecological and societal goods and services. Major local threats to mangrove ecosystems worldwide include clearcutting and trimming of forests for urban, agricultural, or industrial expansion; hydrological alterations; toxic chemical spills; and eutrophication. In many countries with mangroves, much of the human population resides in the coastal zone, and their activities often negatively impact the integrity of mangrove forests. In addition, eutrophication, which is the process whereby nutrients build up to higher than normal levels in a natural system, is possibly one of the most serious threats to mangroves and associated ecosystems such as coral reefs. Scientists with the U.S. Geological Survey (USGS) at the National Wetlands Research Center are working to more fully understand global impacts on these significant ecosystems.Changes in climate and other factors may also affect mangroves, but in complex ways. Global warming may promote expansion of mangrove forests to higher latitudes and accelerate sea-level rise through melting of polar ice or steric expansion of oceans. Changes in sea level would alter flooding patterns and the structure and areal extent of mangroves. Climate change may also alter rainfall patterns, which would in turn change local salinity regimes and competitive interactions of mangroves with other wetland species. Increases in frequency or intensity of tropical storms and hurricanes in combination with sea-level rise may alter erosion and sedimentation rates in mangrove forests. Another global change factor that may directly affect mangrove growth is increased atmospheric carbon dioxide (CO2), caused by burning of fossil fuels and other factors. Elevated CO2 concentration may increase mangrove growth by stimulating photosynthesis or improving water use

  20. Monotoring of mangrove ecosystem in relation with exploration and production activities

    SciTech Connect

    Alamsyah, C.; Dwistiadi, D.

    1996-11-01

    From Indonesia`s initial 13 million hectares of mangrove forests, presently only 2.6 million hectares remains which must be certainly protected. Mangrove swamps are of considerable ecological importance not only because of their use as spawning and feeding grounds for a many variety of fish and shrimps but also of economical importance and last but not least as coastal protection. In such a sensitive ecosystem, i.e. in the mangrove swamp area of Mahakam Delta in East Kalimantan, Indonesia, TOTAL Indonesie, an affiliate of the French oil company {open_quotes}TOTAL{close_quotes} and one of the production sharing contractors of PERTAMINA, the Indonesian owned state oil company, has undertaken its E&P operations since 1974. Realizing the sensitivity of the mangrove area, TOTAL Indonesie has undertaken continuous monitoring of the environment as part of its Environmental Management System. This monitoring is very important not only to measure the impact to the mangrove ecosystem in particular due to TOTAL Indonesie activities but also as a feed back for the environmental management. Physicochemical and biological aspects of the environment are monitored and various measurements are taken covering: (1) Hydrology and hydrodynamics of the water streams i.e. the water quality, productivity and flow characteristic of the region (2) Sedimentation and biodegradation (3) The influence of accidental and chronic pollution mangrove ecosystem (3) Sensitivity of the mangroves. The above monitoring has led to the conclusion that after more than 20 years of operation, there has significant adverse impact to the mangrove ecosystem by the exploration and production activities of Indonesie.

  1. Forest health monitoring 1992 annual statistical summary. Project report

    SciTech Connect

    Aalexander, S.A.; Barnard, J.E.

    1994-04-01

    In 1990, the U.S. Department of Agriculture (USDA) Forest Service (FS) and the U.S. Environmental Protection Agency (EPA) initiated a cooperative national program to monitor the condition of the nation's forests. This multi-agency effort, within EPA's Environmental Monitoring and Assessment Program (EMAP), is called the Forest Health Monitoring (FHM) program. In 1992, Detection Monitoring activities were conducted in twelve states: Alabama; Connecticut; Delaware; Georgia; Maine; Maryland; Massachusetts; New Hampshire; New Jersey; Rhode Island; Vermont; and Virginia. Data analysis results for the following indicators are presented; tree species and stand density (mensuration); tree crown condition; tree species diversity; and air pollution bioindicator plants. The cumulative distribution function methods used in the analysis provide a statistical summary of most measurements. Tabular summaries were also prepared in some cases.

  2. Baseline data on forest loss and associated uncertainty: advances in national forest monitoring

    NASA Astrophysics Data System (ADS)

    Pelletier, Johanne; Goetz, Scott J.

    2015-02-01

    Countries participating in climate change mitigation via the United Nations Framework Convention on Climate Change reducing emissions from deforestation and forest degradation mechanism are required to establish national forest monitoring systems. The design of national forest monitoring system includes provision of transparent, consistent and accurate estimates of emissions and removals from forests, while also taking into account national circumstances and capabilities. One key component of these systems lies in satellite remote sensing approaches and techniques to determine baseline data on forest loss against which future rates of change can be evaluated. Advances in approaches meeting these criteria for measuring, reporting and verification purposes are therefore of tremendous interest. A robust example advancing such approaches, focused on Peru, is provided in the recent paper of Potapov et al (2014 Environ. Res. Lett. 9 124012).

  3. Plant-plant interactions in a subtropical mangrove-to-marsh transition zone: effects of environmental drivers

    USGS Publications Warehouse

    Howard, Rebecca J.; Krauss, Ken W.; Cormier, Nicole; Day, Richard H.; Biagas, Janelda M.; Allain, Larry K.

    2015-01-01

    Questions Does 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? Location Subtropical coastal region of the southern United States. Methods We 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. Results Establishment 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

  4. The role of mangroves in attenuating storm surges

    USGS Publications Warehouse

    Zhang, Keqi; Liu, Huiqing; Li, Yuepeng; Xu, Hongzhou; Shen, Jian; Rhome, Jamie; Smith, J.

    2012-01-01

    Field observations and numerical simulations indicate that the 6-to-30-km-wide mangrove forest along the Gulf Coast of South Florida effectively attenuated stormsurges from a Category 3 hurricane, Wilma, and protected the inland wetland by reducing an inundation area of 1800 km2 and restricting surge inundation inside the mangrove zone. The surge amplitude decreases at a rate of 40–50 cm/km across the mangrove forest and at a rate of 20 cm/km across the areas with a mixture of mangrove islands with open water. In contrast, the amplitudes of stormsurges at the front of the mangrove zone increase by about 10–30% because of the "blockage" of mangroves to surge water, which can cause greater impacts on structures at the front of mangroves than the case without mangroves. The mangrove forest can also protect the wetlands behind the mangrove zone against surge inundation from a Category 5 hurricane with a fast forward speed of 11.2 m/s (25 mph). However, the forest cannot fully attenuate stormsurges from a Category 5 hurricane with a slow forward speed of 2.2 m/s (5 mph) and reduced surges can still affect the wetlands behind the mangrove zone. The effects of widths of mangrove zones on reducing surge amplitudes are nonlinear with large reduction rates (15–30%) for initial width increments and small rates (<5%) for subsequent width increments.

  5. Acid leachable trace metals in sediment cores from Sunderban Mangrove Wetland, India: an approach towards regular monitoring.

    PubMed

    Jonathan, M P; Sarkar, S K; Roy, P D; Alam, Md A; Chatterjee, M; Bhattacharya, B D; Bhattacharya, A; Satpathy, K K

    2010-02-01

    The paper presents the first document to identify the enrichment pattern of acid leachable trace metals (ALTMs) such as Fe, Mn, Cr, Cu, Ni, Pb, Cd, Co, Mo, Ag, As and Ba and their relationship with sediment quality parameters (pH, organic carbon, carbonates and texture) in core sediments (<63 microm particle size) from Indian Sunderban mangrove wetland, formed at the estuarine phase of the river Hugli (Ganges). Textural analysis reveals an overall predominance of mud. The results indicate that the change in pH values causes coagulation and precipitation of ALTMs. Fe and Mn have fairly close distribution patterns of enrichment in surface layers which might be ascribed to early diagnetic processes. The most prominent feature of ALTMs is the enrichment of Fe, Mn, Cr, Cu, Ni, Pb, and Ba in the surface-subsurface layers in the sediment cores, which is mainly attributed to the intense industrial and agricultural activities as well as drainage of untreated domestic sewage to this coastal region. The ALTMs also indicate their association with organic carbon and Fe-Mn oxyhydroxides. The enrichment is well--supported by the correlation, grouping and clustering of ALTMs in statistical analyses. Anthropogenic Factor values indicated ALTMs enrichment for all trace metals due to intense anthropogenic activities. Overall higher values of ALTMs in sediments in comparison to other Indian coastal regions indicate that they are mainly due to the uncontrolled anthropogenic activities in this mangrove estuarine complex. Statistical analyses suggest that five ALTMs (Cu, Pb, As, Mo, Ba) are attached to the organic particles and the clustering of elements separately also indicates that they are from external source. The result of the present study suggests the need for a regular monitoring program which will help to improve the quality of this potential wetland.

  6. Recent advances in understanding Colombian mangroves

    NASA Astrophysics Data System (ADS)

    Polanía, J.; Urrego, L. E.; Agudelo, C. M.

    2015-02-01

    Throughout the last 15 years, researchers at the National University of Colombia at Medellin have studied Colombian mangroves. Remote sensing, pollen analysis of superficial and deep sediments, Holocene coastal vegetation dynamics, sediment dating using 14C and 210Pb, sampling in temporary plots, sampling in temporary and permanent plots, and other techniques have been applied to elucidate long- and short-term mangrove community dynamics. The studied root fouling community is structured by several regulatory mechanisms; habitat heterogeneity increases species richness and abundance. Fringe mangroves were related to Ca concentration in the soil and the increased dominance of Laguncularia racemosa and other nonmangrove tree species, while the riverine mangroves were associated with Mg concentration and the dominance of Rhizophora mangle. The seedling and mangrove tree distributions are determined by a complex gradient of natural and anthropogenic disturbances. Mangrove pollen from surface sediments and the existing vegetation and geomorphology are close interrelated. Plant pollen of mangrove and salt marsh reflects environmental and disturbance conditions, and also reveals forest types. Forest dynamics in both coasts and their sensitivity of to anthropogenic processes are well documented in the Late Quaternary fossil record. Our studies of short and long term allow us to predict the dynamics of mangroves under different scenarios of climate change and anthropogenic stress factors that are operating in Colombian coasts. Future research arises from these results on mangrove forests dynamics, sea-level rise at a fine scale using palynology, conservation biology, and carbon dynamics.

  7. Taiga forest stands and SAR: Monitoring for subarctic global change

    SciTech Connect

    Way, J.; Kwok, R.; Viereck, L.; Slaughter, C.; Dobson, C.

    1992-03-01

    In preparation for the first European Earth Remote Sensing (ERS-1) mission, a series of multitemporal, multifrequency, multipolarization aircraft synthetic aperture radar (SAR) data sets were acquired over the Bonanza Creek Experimental Forest near Fairbanks, Alaska in March 1988. Significant change in radar backscatter was observed over the two-week experimental period due to changing environmental conditions. These preliminary results are presented to illustrate the opportunity afforded by the ERS-1 SAR to monitor temporal change in forest ecosystems.

  8. Monitoring forest structure at landscape level: a case study of Scots pine forest in NE Turkey.

    PubMed

    Terzioğlu, Salih; Başkent, Emin Zeki; Kadioğullari, Ali Ihsan

    2009-05-01

    This study aims to investigate the change in spatial-temporal configuration of secondary forest succession and generate measurements for monitoring the changes in structural plant diversity in Yalnizçam Scots pine forest in NE Turkey from 1972 to 2005. The successional stages were mapped using the combination of Geographic Information System (GIS), Global Positioning System (GPS), aerial photos and high resolution satellite images (IKONOS). Forest structure and its relationship with structural plant diversity along with its changes over time were characterized using FRAGSTATS. In terms of spatial configuration of seral stages, the total number of fragments increased from 572 to 735, and mean size of patch (MPS) decreased from 154.97 ha to 120.60 ha over 33 years. The situation resulted in forestation serving appropriate conditions for plant diversity in the area. As an overall change in study area, there was a net increase of 1823.3 ha forest during the period with an average annual forestation rate of 55.25 ha year(-1) (0.4% per year). In conclusion, the study revealed that stand type maps of forest management plans in Turkey provide a great chance to monitor the changes in structural plant diversity over time. The study further contributes to the development of a framework for effective integration of biodiversity conservation into Multiple Use Forest Management (MUFM) plans using the successional stages as a critical mechanism. PMID:18553149

  9. Environmental monitoring of pesticide exposure and effects on mangrove aquatic organisms of Mozambique.

    PubMed

    Sturve, Joachim; Scarlet, Perpetua; Halling, Maja; Kreuger, Jenny; Macia, Adriano

    2016-10-01

    The use of pesticides in Mozambique is increasing along with the development of agriculture in the country. Mangroves along the coastlines are ecologically important areas and vital nursing grounds for many aquatic species, several of which are of high economic value in Mozambique. Barred mudskipper (Periophthalmus argentilineatus), Jarbua fish (Terapon jarbua), Indian white prawn (Penaeus indicus) and the clam Meretrix meretrix were collected at three mangrove sites in the Maputo Bay area. This was complemented with samplings of the freshwater fish Mozambique tilapia (Oreochromis mossambicus), which was collected from three sampling sites along rivers in the surroundings of Maputo and from three sites along the Olifants and Limpopo River. Acetylcholinesterase (AChE) activity, which is an established biomarker for organophosphates and carbamate pesticides, was measured in brain and liver tissue in fish, and hepatopancreas tissue in prawn and clam. Butyrylcholinesterase (BChE) activity was also analyzed. Freshwater samples for pesticide analyses were collected in order to get an initial understanding of the classes and levels of pesticides present in aquatic systems in Mozambique. In addition to field samplings two 48-h exposure experiments were also conducted where the Indian white prawn and Barred mudskipper were exposed to malathion, and Mozambique tilapia exposed to malathion and diazinon. Field results show a significant decrease in AChE activity in fish from four of the sampling sites suggesting that pesticides present in water could be one stressor potentially affecting aquatic organisms negatively. The 48 h exposure experiment results showed a clear dose-response relationship of AChE activity in mudskipper and tilapia suggesting these species as suitable as sentinel species in environmental studies. PMID:27422103

  10. Environmental monitoring of pesticide exposure and effects on mangrove aquatic organisms of Mozambique.

    PubMed

    Sturve, Joachim; Scarlet, Perpetua; Halling, Maja; Kreuger, Jenny; Macia, Adriano

    2016-10-01

    The use of pesticides in Mozambique is increasing along with the development of agriculture in the country. Mangroves along the coastlines are ecologically important areas and vital nursing grounds for many aquatic species, several of which are of high economic value in Mozambique. Barred mudskipper (Periophthalmus argentilineatus), Jarbua fish (Terapon jarbua), Indian white prawn (Penaeus indicus) and the clam Meretrix meretrix were collected at three mangrove sites in the Maputo Bay area. This was complemented with samplings of the freshwater fish Mozambique tilapia (Oreochromis mossambicus), which was collected from three sampling sites along rivers in the surroundings of Maputo and from three sites along the Olifants and Limpopo River. Acetylcholinesterase (AChE) activity, which is an established biomarker for organophosphates and carbamate pesticides, was measured in brain and liver tissue in fish, and hepatopancreas tissue in prawn and clam. Butyrylcholinesterase (BChE) activity was also analyzed. Freshwater samples for pesticide analyses were collected in order to get an initial understanding of the classes and levels of pesticides present in aquatic systems in Mozambique. In addition to field samplings two 48-h exposure experiments were also conducted where the Indian white prawn and Barred mudskipper were exposed to malathion, and Mozambique tilapia exposed to malathion and diazinon. Field results show a significant decrease in AChE activity in fish from four of the sampling sites suggesting that pesticides present in water could be one stressor potentially affecting aquatic organisms negatively. The 48 h exposure experiment results showed a clear dose-response relationship of AChE activity in mudskipper and tilapia suggesting these species as suitable as sentinel species in environmental studies.

  11. Sap flow characteristics of neotropical mangroves in flooded and drained soils.

    PubMed

    Krauss, Ken W; Young, P Joy; Chambers, Jim L; Doyle, Thomas W; Twilley, Robert R

    2007-05-01

    Effects of flooding on water transport in mangroves have previously been investigated in a few studies, most of which were conducted on seedlings in controlled settings. In this study, we used heat-dissipation sap probes to determine if sap flow (J(s)) attenuates with radial depth into the xylem of mature trees of three south Florida mangrove species growing in Rookery Bay. This was accomplished by inserting sap probes at multiple depths and monitoring diurnal flow. For most species and diameter size class combinations tested, J(s) decreased dramatically beyond a radial depth of 2 or 4 cm, with little sap flow beyond a depth of 6 cm. Mean J(s) was reduced on average by 20% in Avicennia germinans (L.) Stearn, Laguncularia racemosa (L.) Gaertn. f. and Rhizophora mangle L. trees when soils were flooded. Species differences were highly significant, with L. racemosa having the greatest midday J(s) of about 26 g H(2)O m(-2) s(-1) at a radial depth of 2 cm compared with a mean for the other two species of about 15 g H(2)O m(-2) s(-1). Sap flow at a depth of 2 cm in mangroves was commensurate with rates reported for other forested wetland tree species. We conclude that: (1) early spring flooding of basin mangrove forests causes reductions in sap flow in mature mangrove trees; (2) the sharp attenuations in J(s) along the radial profile have implications for understanding whole-tree water use strategies by mangrove forests; and (3) regardless of flood state, individual mangrove tree water use follows leaf-level mechanisms in being conservative. PMID:17267368

  12. Sap flow characteristics of neotropical mangroves in flooded and drained soils

    USGS Publications Warehouse

    Krauss, Ken W.; Young, P. Joy; Chambers, Jim L.; Doyle, Thomas W.; Twilley, Robert R.

    2007-01-01

    Effects of flooding on water transport in mangroves have previously been investigated in a few studies, most of which were conducted on seedlings in controlled settings. In this study, we used heat-dissipation sap probes to determine if sap flow (Js) attenuates with radial depth into the xylem of mature trees of three south Florida mangrove species growing in Rookery Bay. This was accomplished by inserting sap probes at multiple depths and monitoring diurnal flow. For most species and diameter size class combinations tested, Js decreased dramatically beyond a radial depth of 2 or 4 cm, with little sap flow beyond a depth of 6 cm. Mean Js was reduced on average by 20% in Avicennia germinans (L.) Stearn, Laguncularia racemosa (L.) Gaertn. f. and Rhizophora mangle L. trees when soils were flooded. Species differences were highly significant, with L. racemosahaving the greatest midday Js of about 26g H2O H2O m−2s−1 at a radial depth of 2 cm compared with a mean for the other two species of about 15 g H2O m−2s−1. Sap flow at a depth of 2 cm in mangroves was commensurate with rates reported for other forested wetland tree species. We conclude that: (1) early spring flooding of basin mangrove forests causes reductions in sap flow in mature mangrove trees; (2) the sharp attenuations in Js along the radial profile have implications for understanding whole-tree water use strategies by mangrove forests; and (3) regardless of flood state, individual mangrove tree water use follows leaf-level mechanisms in being conservative.

  13. Role and design of water quality monitoring on forested watersheds

    SciTech Connect

    Chen, Y.D.; Rasmussen, T.C.

    1993-01-01

    The role of water quality monitoring is important for resolving issues related to the selection of Best Management Practices for silvicultural nonpoint source pollution control. Water quality monitoring provides direct information related to the suitability of various management options and to the simulation of water quality processes. In addition to the traditional physical and chemical parameters, the monitoring should focus on other environmental and biological indicators of ecosystem structure and function. A framework for designing water quality monitoring systems is presented that includes the special conditions exhibited by forested watersheds.

  14. Monitoring Fires in Southwestern Amazonia Rain Forests

    NASA Astrophysics Data System (ADS)

    Brown, I. Foster; Schroeder, Wilfrid; Setzer, Alberto; de Los Rios Maldonado, Monica; Pantoja, Nara; Duarte, Alejandro; Marengo, Jose

    2006-06-01

    From mid-July to mid-October 2005, an environmental disaster unfolded in the trinational region of Madre de Dios, Peru; Acre, Brazil; and Pando, Bolivia (the MAP region), in southwestern Amazonia. A prolonged dry season and human-initiated fires resulted in smoke pollution affecting more than 400,000 persons, fire damage to over 300,000 hectares of rain forest, and over US$50 million of direct economic losses. Indicators suggest that anomalous drought conditions could occur again this year.

  15. Classification of mangroves vegetation species using texture analysis on Rapideye satellite imagery

    NASA Astrophysics Data System (ADS)

    Roslani, M. A.; Mustapha, M. A.; Lihan, T.; Juliana, W. A. Wan

    2013-11-01

    Mangroves are unique ecosystem structures that are typically made up of salt tolerant species of vegetation that can be found in tropical and subtropical climate country. Mangrove ecosystem plays important role and also is known as highly productive ecosystem with high diversity of flora and fauna. However, these ecosystems have been declining over time due to the various kinds of direct and indirect pressures. Thus, there is an increasing need to monitor and assess this ecosystem for better conservation and management efforts. The multispectral RapidEye satellite image was used to identify the mangrove vegetation species within the Matang Mangrove Forest Reserve in Perak, Malaysia using texture analysis. Classification was implemented using the maximum likelihood classifier (MLC) method. Total of eleven main mangrove species were found in the satellite image of the study site which includes Rhizophora mucronata, Rhizophora apiculata, Bruguiera parviflora, Bruguiera cylindrica, Bruguiera gymnorrhiza, Avicennia alba, Avicennia officinalis, Sonneratia alba, Sonneratia caseolaris, Sonneratia ovata and Xylocarpus granatum. The classification results showed that the textured image produced high overall classification assessment recorded at 84% and kappa statistic of 0.8016. Meanwhile, the non-textured image produces 80% of overall accuracy and kappa statistic of 0.7061. The classification result indicated the capability of high resolution satellite image to classify the mangrove species and inclusion of texture information in the classification increased the classification accuracy.

  16. Application of Remote Sensing Technologies for Forest Cover Monitoring

    NASA Astrophysics Data System (ADS)

    Agoltsov, Alexander; Sizov, Oleg; Rubtsova, Natalia

    2014-05-01

    Today we don't have full and reliable information about forests in Russia, so it is impossible to make any well-timed decision for forest management. Update of all this information by means of traditional methods (fieldwork) is a time-consuming and in fact impossible task. Also we do not think that using of the reports without objective information for cameral data actualization is an appropriate method in such situation. So our company uses remote sensing data and technologies to resolve this problem. Nowadays numerous satellites record numerous images every day. Remote sensing data are widespread and accessible, so we can use them as the source of actual and reliable information about current status of the Forest Fund. Furthermore regular monitoring allows extracting the information about the location and intensity of forests' changes like degradation and destruction. First of all we create a georeferenced data set to cover the area of interest with orthomosaic in targeting scale depending on the goals of the project (1:25 000 - 1:10 000). For example, we can do a mosaic from RapidEye (Germany) imagery with GSD = 6.5 m or from WorldView-2 (USA) imagery with GSD = 0.5 m. The next step is to create vector layers to describe the content of images. We use visual and contemporary automatic interpretation techniques. The benefit of such approach that we can extract not only information about forests (like boundary) but also the information about roads, hydrographic objects, power lines and so on. During vectorization except relevant orthomosaic we can use multi-temporal composites of images based on archive of satellite imagery. This helps us not only to detect general changes but detect illegal logging, areas affected by fires, windfalls. Then this information can be used for different products e.g. forest cover statistics, forest cover change statistics, maps of forest management and also we can analyze transport accessibility and economic assessment of forests.

  17. An Approach to Monitoring Mangrove Extents Through Time-Series Comparison of JERS-1 SAR and ALOS PALSAR Data

    NASA Technical Reports Server (NTRS)

    Thomas, Nathan; Lucas, Richard; Itoh, Takuya; Simard, Marc; Fatoyinbo, Lucas; Bunting, Peter; Rosenqvist, Ake

    2014-01-01

    Between 2007 and 2010, Japan's Advanced Land Observing Satellite (ALOS) Phased Arrayed L-band Synthetic Aperture Radar (PALSAR) captured dual polarization HH and HV data across the tropics and sub-tropics. A pan tropical dataset of Japanese Earth Resources Satellite (JERS-1) SAR (HH) data was also acquired between 1995 and 1998. The provision of these comparable cloud-free datasets provided an opportunity for observing changes in the extent of coastal mangroves over more than a decade. Focusing on nine sites distributed through the tropics, this paper demonstrates how these data can be used to backdate and update existing baseline maps of mangrove extent. The benefits of integrating dense timeseries of Landsat sensor data for both validating assessments of change and determining the causes of change are outlined. The approach is evaluated for wider application across the geographical range of mangroves in order to advance the development of JAXA's Global Mangrove Watch (GMW) program.

  18. Ecology of the mangroves of south Florida: a community profile

    SciTech Connect

    Odum, W.E.; McIvor, C.C.; Smith, T.J. III

    1982-01-01

    A detailed description is given of the community structure and ecosystem processes of the mangrove forests of south Florida. This description is based upon a compilation of data and hypotheses from published and unpublished sources. Information covered ranges from details of mangrove distribution, primary production, and diseases to asepcts of reproduction, biomass partitioning, and adaptations to stress. Mangrove ecosystems are considered in terms of zonation, succession, litter fall and decomposition, carbon export, and energy flow. Most of the components of mangrove communities are cataloged and discussed; these include mircoorganisms, plants other than mangroves, invertebrates, fishes, reptiles, amphibians, birds, and mammals. Finally, two sections summarize the value of mangrove ecosystems to man and present ways to manage this type of habitat. It is concluded that mangrove forests, which cover between 430,000 and 500,000 acres (174,000 to 202,000 ha) in Florida, are a resource of great value and should be protected and preserved wherever possible.

  19. Temporal variability of carbon and nutrient burial, sediment accretion, and mass accumulation over the past century in a carbonate platform mangrove forest of the Florida Everglades.

    USGS Publications Warehouse

    Breithaupt, Josh L.; Smoak, Joseph M.; Smith, Thomas J.; Sanders, Christian J.

    2014-01-01

    The objective of this research was to measure temporal variability in accretion and mass sedimentation rates (including organic carbon (OC), total nitrogen (TN), and total phosphorous (TP)) from the past century in a mangrove forest on the Shark River in Everglades National Park, USA. The 210Pb Constant Rate of Supply model was applied to six soil cores to calculate annual rates over the most recent 10, 50, and 100 year time spans. Our results show that rates integrated over longer timeframes are lower than those for shorter, recent periods of observation. Additionally, the substantial spatial variability between cores over the 10 year period is diminished over the 100 year record, raising two important implications. First, a multiple-decade assessment of soil accretion and OC burial provides a more conservative estimate and is likely to be most relevant for forecasting these rates relative to long-term processes of sea level rise and climate change mitigation. Second, a small number of sampling locations are better able to account for spatial variability over the longer periods than for the shorter periods. The site average 100 year OC burial rate, 123 ± 19 (standard deviation) g m-2yr-1, is low compared with global mangrove values. High TN and TP burial rates in recent decades may lead to increased soil carbon remineralization, contributing to the low carbon burial rates. Finally, the strong correlation between OC burial and accretion across this site signals the substantial contribution of OC to soil building in addition to the ecosystem service of CO2 sequestration.

  20. Temporal variability of carbon and nutrient burial, sediment accretion, and mass accumulation over the past century in a carbonate platform mangrove forest of the Florida Everglades

    NASA Astrophysics Data System (ADS)

    Breithaupt, Joshua L.; Smoak, Joseph M.; Smith, Thomas J.; Sanders, Christian J.

    2014-10-01

    The objective of this research was to measure temporal variability in accretion and mass sedimentation rates (including organic carbon (OC), total nitrogen (TN), and total phosphorous (TP)) from the past century in a mangrove forest on the Shark River in Everglades National Park, USA. The 210Pb Constant Rate of Supply model was applied to six soil cores to calculate annual rates over the most recent 10, 50, and 100 year time spans. Our results show that rates integrated over longer timeframes are lower than those for shorter, recent periods of observation. Additionally, the substantial spatial variability between cores over the 10 year period is diminished over the 100 year record, raising two important implications. First, a multiple-decade assessment of soil accretion and OC burial provides a more conservative estimate and is likely to be most relevant for forecasting these rates relative to long-term processes of sea level rise and climate change mitigation. Second, a small number of sampling locations are better able to account for spatial variability over the longer periods than for the shorter periods. The site average 100 year OC burial rate, 123 ± 19 (standard deviation) g m-2 yr-1, is low compared with global mangrove values. High TN and TP burial rates in recent decades may lead to increased soil carbon remineralization, contributing to the low carbon burial rates. Finally, the strong correlation between OC burial and accretion across this site signals the substantial contribution of OC to soil building in addition to the ecosystem service of CO2 sequestration.

  1. Short-term dissolved oxygen patterns in sub-tropical mangroves

    NASA Astrophysics Data System (ADS)

    Knight, Jon M.; Griffin, Lachlan; Dale, Pat E. R.; Sheaves, Marcus

    2013-10-01

    Mangrove forests in subtropical areas are highly heterogeneous environments, influenced by diverse physical structures and tidal flushing regimes. An important component of tidal water is the concentration of dissolved oxygen (DO), as it affects aquatic organisms such as fish (directly: respiration and behaviour) and immature mosquitoes (directly: trigger for egg-hatch; indirectly: fish predation of larvae). Changes in DO may be important over relatively small time scales such as minutes and days, but, at such scales it has received little investigation. The aim of this study was to address this knowledge gap, monitoring DO at small time intervals (1 min) over tidal flooding events (hours - days) in two contrasting subtropical mangrove systems. These represented a range of mangrove tidal hydrology: a well-connected fringing mangrove forest in south-east Queensland and a more complex mangrove basin forest in northern New South Wales with impeded tidal connections. The results indicated that patterns of DO varied diurnally and by mangrove system. In the fringing forest, where the substrate was exposed before and after flooding, the highest mean DO concentration was during the day, followed by evening, with pre-dawn the lowest (6.8, 6.5 and 6.1 mg/l, respectively). DO patterns differed by tide stage and time of day with falling DO especially during late evening and pre-dawn as tides ebbed. In the mangrove basin forest the pattern was reversed, but also depended on the distance the tide had travelled across the basin. Before tidal incursion, standing water in the basin was anoxic (DO 0 mg/l). As tidal water flooded into the systems there was a greater increase in DO closer to the tide source than further away, with a DO concentration of 7.6 mg/l compared to 5.4 mg/l. The observations were interpreted in the light of processes and potential impacts on aquatic organisms (fish and immature mosquitoes). The most significant observation was that in the mangrove basin DO

  2. Monitoring Carbon Assimilation of South American Tropical Forests

    NASA Astrophysics Data System (ADS)

    Costa, M. H.; Nunes, E. L.

    2009-12-01

    Net primary production (NPP) is a key variable for monitoring and understanding the impacts of environmental change on ecosystems and for generating realistic global and regional carbon budgets. However, although assessment of NPP over broad spatial scales has been made possible through the development of MODIS products such as MOD17A3, such global remotely sensed estimations are often inaccurate due to algorithm failure and parameterization issues. These inadequacies can be partly remedied by the development of biome-specific geographically localized algorithms. In this paper we develop a regional algorithm (RATE) for the automatic monitoring the rate of carbon fixation (as measured by NPP) of tropical forests in South America. The algorithm is based on a modification of the SITE model and uses data from the MODIS sensor (MOD12Q1 and MOD15A2 products) and meteorological data from the National Centers for Environmental Prediction (NCEP). The effectiveness of the algorithm was tested in eight field sites from two types of tropical forests in South America: the Amazon rainforest and the Atlantic forest. In the Amazonian sites, the RATE algorithm produced NPP values closer to the observed values than estimates from the MODIS NPP product, while in the Atlantic forest sites it generated NPP values similar to the MODIS sensor. In conclusion, RATE appears to be a reliable estimator of carbon fixation by tropical forests in South America, with an average error of only 4.7%, and is therefore a more precise way of monitoring regional environmental change in these globally important ecosystems.

  3. [Costa Rica mangroves: the north Pacific].

    PubMed

    Zamora-Trejos, Priscilla; Cortés, Jorge

    2009-09-01

    Costa Rica has mangrove forests on both the Caribbean and Pacific coasts. The Pacific side has 99% of the mangrove area of the country. In this review we compile available information on the mangroves of the north Pacific coast of Costa Rica, from Bahía Salinas, on the border with Nicaragua, to the tip of the Peninsula de Nicoya at Cabo Blanco. We provide information on the location of the mangroves and all available information for each mangrove forest. These mangrove communities are smaller in extension and tree sizes, and have lower diversity compared to the mangroves on the southern section of the Pacific coast of Costa Rica. The dominant species are Rhizophora mangle and Rhizophora racemosa along the canal edges, backed by Avicennia germinans, and farther inland Avicennia bicolor, Laguncularia racemosa and Conocarpus erectus. At Potrero Grande a healthy population of Pelliciera rhizophorae, a rare species, has been reported. We recognized 38 mangrove communities in this part of the country, based on the National Wetland Inventory, published papers, field observations, theses, technical reports, and the national topographic maps (1:50,000, Instituto Geográfico Nacional). Relatively detailed information could be found for only five mangrove forests, for 14 more only prelimary and incomplete lists of plants and in some cases of animal species are available, for nine there is even less information, and for nine more only their location is known, which in some cases was not correct. Detail mapping, characterization of the vegetation and fauna, physiological studies, analyses of biogeochemical and physical processes, economic valuations, and determination of the health status of the mangrove of the northern Pacific coast, as well as for the rest of Costa Rica, are neccesary and urgent.

  4. [Costa Rica mangroves: the north Pacific].

    PubMed

    Zamora-Trejos, Priscilla; Cortés, Jorge

    2009-09-01

    Costa Rica has mangrove forests on both the Caribbean and Pacific coasts. The Pacific side has 99% of the mangrove area of the country. In this review we compile available information on the mangroves of the north Pacific coast of Costa Rica, from Bahía Salinas, on the border with Nicaragua, to the tip of the Peninsula de Nicoya at Cabo Blanco. We provide information on the location of the mangroves and all available information for each mangrove forest. These mangrove communities are smaller in extension and tree sizes, and have lower diversity compared to the mangroves on the southern section of the Pacific coast of Costa Rica. The dominant species are Rhizophora mangle and Rhizophora racemosa along the canal edges, backed by Avicennia germinans, and farther inland Avicennia bicolor, Laguncularia racemosa and Conocarpus erectus. At Potrero Grande a healthy population of Pelliciera rhizophorae, a rare species, has been reported. We recognized 38 mangrove communities in this part of the country, based on the National Wetland Inventory, published papers, field observations, theses, technical reports, and the national topographic maps (1:50,000, Instituto Geográfico Nacional). Relatively detailed information could be found for only five mangrove forests, for 14 more only prelimary and incomplete lists of plants and in some cases of animal species are available, for nine there is even less information, and for nine more only their location is known, which in some cases was not correct. Detail mapping, characterization of the vegetation and fauna, physiological studies, analyses of biogeochemical and physical processes, economic valuations, and determination of the health status of the mangrove of the northern Pacific coast, as well as for the rest of Costa Rica, are neccesary and urgent. PMID:19928448

  5. Applications of turbidity monitoring to forest management in California.

    PubMed

    Harris, Richard R; Sullivan, Kathleen; Cafferata, Peter H; Munn, John R; Faucher, Kevin M

    2007-09-01

    Many California streams have been adversely affected by sedimentation caused by historic and current land uses, including timber harvesting. The impacts of timber harvesting and logging transportation systems on erosion and sediment delivery can be directly measured, modeled, or inferred from water quality measurements. California regulatory agencies, researchers, and land owners have adopted turbidity monitoring to determine effects of forest management practices on suspended sediment loads and water quality at watershed, project, and site scales. Watershed-scale trends in sediment discharge and responses to current forest practices may be estimated from data collected at automated sampling stations that measure turbidity, stream flow, suspended sediment concentrations, and other water quality parameters. Future results from these studies will provide a basis for assessing the effectiveness of modern forest practice regulations in protecting water quality. At the project scale, manual sampling of water column turbidity during high stream flow events within and downstream from active timber harvest plans can identify emerging sediment sources. Remedial actions can then be taken by managers to prevent or mitigate water quality impacts. At the site scale, manual turbidity sampling during storms or high stream flow events at sites located upstream and downstream from new, upgraded, or decommissioned stream crossings has proven to be a valuable way to determine whether measures taken to prevent post-construction erosion and sediment production are effective. Turbidity monitoring at the project and site scales is therefore an important tool for adaptive management. Uncertainty regarding the effects of current forest practices must be resolved through watershed-scale experiments. In the short term, this uncertainty will stimulate increased use of project and site-scale monitoring. PMID:17562100

  6. Monitoring Forest Regrowth Using a Multi-Platform Time Series

    NASA Technical Reports Server (NTRS)

    Sabol, Donald E., Jr.; Smith, Milton O.; Adams, John B.; Gillespie, Alan R.; Tucker, Compton J.

    1996-01-01

    Over the past 50 years, the forests of western Washington and Oregon have been extensively harvested for timber. This has resulted in a heterogeneous mosaic of remaining mature forests, clear-cuts, new plantations, and second-growth stands that now occur in areas that formerly were dominated by extensive old-growth forests and younger forests resulting from fire disturbance. Traditionally, determination of seral stage and stand condition have been made using aerial photography and spot field observations, a methodology that is not only time- and resource-intensive, but falls short of providing current information on a regional scale. These limitations may be solved, in part, through the use of multispectral images which can cover large areas at spatial resolutions in the order of tens of meters. The use of multiple images comprising a time series potentially can be used to monitor land use (e.g. cutting and replanting), and to observe natural processes such as regeneration, maturation and phenologic change. These processes are more likely to be spectrally observed in a time series composed of images taken during different seasons over a long period of time. Therefore, for many areas, it may be necessary to use a variety of images taken with different imaging systems. A common framework for interpretation is needed that reduces topographic, atmospheric, instrumental, effects as well as differences in lighting geometry between images. The present state of remote-sensing technology in general use does not realize the full potential of the multispectral data in areas of high topographic relief. For example, the primary method for analyzing images of forested landscapes in the Northwest has been with statistical classifiers (e.g. parallelepiped, nearest-neighbor, maximum likelihood, etc.), often applied to uncalibrated multispectral data. Although this approach has produced useful information from individual images in some areas, landcover classes defined by these

  7. Soil microclimate monitoring in forested and meadow sites

    NASA Astrophysics Data System (ADS)

    Freyerova, Katerina; Safanda, Jan

    2016-04-01

    It is well known fact that forest microclimate differs from open area microclimate (Geiger 1965). Less attention is paid to soil temperatures and their long-term monitoring. To evaluate and compare these two environments from the soil microclimate point of view, Institute of Geophysics in Prague monitors soil and air temperatures in Bedřichov in the Jizerské Hory Mountains (Czech Republic). The soil temperatures are measured in three depths (20, 50 and 100 cm) in forest (700 m a. s. l.) and meadow (750 m a. s. l.). Air temperatures are measured at 2m height both in forest and meadow. Nowadays, we have more than three years long time series. The most of studies and experiments described in literature are short-term ones (in order of days or weeks). However, from short-term experiments the seasonal behaviour and trends can be hardly identified and conclusions on soil temperature reaction to climatic extremes such as heat waves, drought or freeze cannot be done with confidence. These drawbacks of the short-term experiments are discussed in literature (eg. Morecroft et al. 1998; Renaud et al. 2011). At the same, with progression of the global warming, the expected increasing frequency of climatic extremes will affect the future form of forest vegetation (Von Arx et al. 2012). The soil and air temperature series, both from the forest and meadow sites, are evaluated and interpreted with respect to long term temperature characteristics and seasonal trends. The emphasis is given on the soil temperature responses to extreme climatic situations. We examine variability between the localities and depths and spatial and temporal changes in this variability. This long-term monitoring allows us to better understand and examine the behaviour of the soil temperature in extreme weather situations. Therefore, we hope to contribute to better prediction of future reactions of this specific environments to the climate change. Literature Geiger, R., 1965. The climate near the ground

  8. Soil microclimate monitoring in forested and meadow sites

    NASA Astrophysics Data System (ADS)

    Freyerova, Katerina; Safanda, Jan

    2016-04-01

    It is well known fact that forest microclimate differs from open area microclimate (Geiger 1965). Less attention is paid to soil temperatures and their long-term monitoring. To evaluate and compare these two environments from the soil microclimate point of view, Institute of Geophysics in Prague monitors soil and air temperatures in Bedřichov in the Jizerské Hory Mountains (Czech Republic). The soil temperatures are measured in three depths (20, 50 and 100 cm) in forest (700 m a. s. l.) and meadow (750 m a. s. l.). Air temperatures are measured at 2m height both in forest and meadow. Nowadays, we have more than three years long time series. The most of studies and experiments described in literature are short-term ones (in order of days or weeks). However, from short-term experiments the seasonal behaviour and trends can be hardly identified and conclusions on soil temperature reaction to climatic extremes such as heat waves, drought or freeze cannot be done with confidence. These drawbacks of the short-term experiments are discussed in literature (eg. Morecroft et al. 1998; Renaud et al. 2011). At the same, with progression of the global warming, the expected increasing frequency of climatic extremes will affect the future form of forest vegetation (Von Arx et al. 2012). The soil and air temperature series, both from the forest and meadow sites, are evaluated and interpreted with respect to long term temperature characteristics and seasonal trends. The emphasis is given on the soil temperature responses to extreme climatic situations. We examine variability between the localities and depths and spatial and temporal changes in this variability. This long-term monitoring allows us to better understand and examine the behaviour of the soil temperature in extreme weather situations. Therefore, we hope to contribute to better prediction of future reactions of this specific environments to the climate change. Literature Geiger, R., 1965. The climate near the ground

  9. Lattice Boltzmann Inverse Modeling of a Tracer Release in an Everglades Mangrove Estuary

    NASA Astrophysics Data System (ADS)

    Sukop, M. C.; Pearson, A. J.; Engel, V.; Ho, D. T.; Ferron Smith, S.

    2011-12-01

    The tidally-dominated Shark River is a major drainage of south Florida. The river passes through and nourishes North America's largest mangrove forest. Strong tidal flows in the river extend more than 12 km upstream from the river's mouth at the Gulf of Mexico. In November 2010, a deliberate release of SF6 tracer into the river was followed for several days to study the river's transport characteristics. During the tracer release and monitoring, tides led to a stage variation of about 0.8 m close to the Gulf and about 0.3 m in the river upstream of the tracer release point. The mangrove forest adjacent to the river is flooded at high tide and consists of mangrove roots and pneumatophores above highly porous peat root mass. Tracer movement and its analysis by conventional methods are complicated by these tidal flows and potentially by interaction with the mangrove zone groundwater. A 30-m resolution 2-dimensional Lattice Boltzmann model was constructed for a 30 x 21 km region of this part of southwestern Florida. Tidal stage boundaries were applied to the east and west edges of the domain. Based on aerial photography and a thresholding process, the domain was separated into open channels representing the complex river network and a porous medium representing the mangrove forest. SF6 concentrations were not monitored in these flood waters or groundwater during this experiment. The objective is to match the simulations to the SF6 observations in order to better understand chemical transport in this environment and to permit simulation of the transport of other species. Numerous conceptual and computational challenges have to be surmounted to apply Lattice Boltzmann methods to this problem.

  10. Description of a marine nematode Hopperia sinensis sp. nov. (Comesomatidae) from mangrove forests of Quanzhou, China, with a pictorial key to Hopperia species

    NASA Astrophysics Data System (ADS)

    Guo, Yuqing; Chang, Yu; Chen, Yuzhen; Li, Yongxiang; Liu, Aiyuan

    2015-12-01

    A new free-living marine nematode species Hopperia sinensis sp. nov. from mangrove forests of Fujian Province, China, is identified and illustrated. Hopperia sinensis sp. nov. is characterized by its cephalic setae 2.4-2.8 µm long or 17%-20% head diameter, and amphids of 2.25-2.5 turns. Lateral differentiation appears with larger, more irregularly distributed dots behind 3-5 transverse rows of dots posterior to amphid. Buccal cavity is consisted of a shallow and weakly sclerotized cup-shaped portion with strongly sclerotized walls of 18-21 µm deep. There are three sclerotized and size-equally pointed teeth at the junction between the two parts. Spicules of 41-45 µm long are slightly curved with broadband velum and central strips at the proximal end. The gubernacula, with apparent lateral guiding pieces, are formed by one central tubular piece that is weakly sclerotized with 11-16 µm long dorso-caudally directed apophyses. There are 13-14 fine tubular precloacal supplements. Conico-cylindrical tail gradually tapers till pointed tail tip. Female is similar to male, but have a longer body and tail. Ovaries are opposed and outstretched, with anterior ovary to the left and posterior ovary to the right of the intestine. A pictorial key to all the valid known species in genus Hopperia is given.

  11. Mangrove plantation over a limestone reef - Good for the ecology?

    NASA Astrophysics Data System (ADS)

    Asaeda, Takashi; Barnuevo, Abner; Sanjaya, Kelum; Fortes, Miguel D.; Kanesaka, Yoshikazu; Wolanski, Eric

    2016-05-01

    There have been efforts to restore degraded tropical and subtropical mangrove forests. While there have been many failures, there have been some successes but these were seldom evaluated to test to what level the created mangrove wetlands reproduce the characteristics of the natural ecosystem and thus what ecosystem services they can deliver. We provide such a detailed assessment for the case of Olango and Banacon Islands in the Philippines where the forest was created over a limestone reef where mangroves did not exist in one island but they covered most of the other island before deforestation in the 1940s and 1950s. The created forest appears to have reached a steady state after 60 years. As is typical of mangrove rehabilitation efforts worldwide, planting was limited to a single Rhizophora species. While a forest has been created, it does not mimic a natural forest. There is a large difference between the natural and planted forests in terms of forest structure and species diversity, and tree density. The high density of planted trees excludes importing other species from nearby natural forests; therefore the planted forest remains mono-specific even after several decades and shows no sign of mimicking the characteristics of a natural forest. The planted forests provided mangrove propagules that invaded nearby natural forests. The planted forest has also changed the substratum from sandy to muddy. The outline of the crown of the planted forest has become smooth and horizontal, contrary to that of a natural forest, and this changes the local landscape. Thus we recommend that future mangrove restoration schemes should modify their methodology in order to plant several species, maintain sufficient space between trees for growth, include the naturally dominant species, and create tidal creeks, in order to reproduce in the rehabilitated areas some of the key ecosystem characteristics of natural mangrove forests.

  12. Monitoring Regional Forest Disturbances across the US with Near Real Time MODIS NDVI Products included in the ForWarn Forest Threat Early Warning System

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Hargrove, William W.; Gasser, Gerald; Norman, Steve

    2013-01-01

    U.S. forests occupy approx.1/3 of total land area (approx. 304 million ha). Since 2000, a growing number of regionally evident forest disturbances have occurred due to abiotic and biotic agents. Regional forest disturbances can threaten human life and property, bio-diversity and water supplies. Timely regional forest disturbance monitoring products are needed to aid forest health management work. Near Real Time (NRT) twice daily MODIS NDVI data provide a means to monitor U.S. regional forest disturbances every 8 days. Since 2010, these NRT forest change products have been produced and posted on the US Forest Service ForWarn Early Warning System for Forest Threats.

  13. The emergence of modern type rain forests and mangroves and their traces in the palaeobotanical record during the Late Cretaceous and early Tertiary

    NASA Astrophysics Data System (ADS)

    Mohr, Barbara; Coiffard, Clément

    2014-05-01

    The origin of modern rain forests is still very poorly known. This ecosystem could have potentially fully evolved only after the development of relatively high numbers of flowering plant families adapted to rain forest conditions. During the early phase of angiosperm evolution in the early Cretaceous the palaeo-equatorial region was located in a seasonally dry climatic belt, so that during this phase, flowering plants often show adaptations to drought, rather than to continuously wet climate conditions. Therefore it is not surprising that except for the Nymphaeales, the most basal members of extant angiosperm families have members that do not necessarily occur in the continuously wet tropics today. However, during the late Early Cretaceous several clades emerged that later would give rise to families that are typically found today mostly in (shady) moist places in warmer regions. This is especially seen among the monocotyledons, a group of the mesangiosperms, that developed in many cases large leaves often with very specific venation patterns that make these leaves very unique and well recognizable. Especially members of three groups are here of interest: the arum family (Araceae), the palms (Arecaceae) and the Ginger and allies (Zingiberales). The earliest fossil of Araceae are restricted to low latitudes during the lower Cretaceous. Arecaceae and Zingiberales do not appear in the fossil record before the early late Cretaceous and occur at mid latitudes. During the Late Cretaceous, Araceae are represented at mid latitudes by non-tropical early diverging members and at low latitudes by derived rainforest members. Palms became widespread during the Late Cretataceous and also Nypa, a typical element of tropical to subtropical mangrove environments evolved during this time period. During the Paleocene Arecaceae appear to be restricted to lower latitudes as well as Zingiberales. All three groups are again widespread during the Eocene, reaching higher latitudes and

  14. Changes in biotic and abiotic processes following mangrove clearing

    NASA Astrophysics Data System (ADS)

    Granek, Elise; Ruttenberg, Benjamin I.

    2008-12-01

    Mangrove forests, important tropical coastal habitats, are in decline worldwide primarily due to removal by humans. Changes to mangrove systems can alter ecosystem properties through direct effects on abiotic factors such as temperature, light and nutrient supply or through changes in biotic factors such as primary productivity or species composition. Despite the importance of mangroves as transitional habitats between land and sea, little research has examined changes that occur when they are cleared. We examined changes in a number of biotic and abiotic factors following the anthropogenic removal of red mangroves ( Rhizophora mangle) in the Panamanian Caribbean, including algal biomass, algal diversity, algal grazing rates, light penetration, temperature, sedimentation rates and sediment organic content. In this first study examining multiple ecosystem-level effects of mangrove disturbance, we found that areas cleared of mangroves had higher algal biomass and richness than intact mangrove areas. This increase in algal biomass and richness was likely due to changes in abiotic factors (e.g. light intensity, temperature), but not biotic factors (fish herbivory). Additionally the algal and cyanobacterial genera dominating mangrove-cleared areas were rare in intact mangroves and included a number of genera that compete with coral for space on reefs. Interestingly, sedimentation rates did not differ between intact and cleared areas, but the sediments that accumulated in intact mangroves had higher organic content. These findings are the first to demonstrate that anthropogenic clearing of mangroves changes multiple biotic and abiotic processes in mangrove forests and that some of these changes may influence adjacent habitats such as coral reefs and seagrass beds. Additional research is needed to further explore the community and ecosystem-level effects of mangrove clearing and their influence on adjacent habitats, but it is clear that mangrove conservation is an

  15. Hurricane disturbance and recovery of energy balance, CO 2 fluxes and canopy structure in a mangrove forest of the Florida Everglades

    USGS Publications Warehouse

    Barr, J.G.; Engel, V.; Smith, T.J.; Fuentes, J.D.

    2012-01-01

    Eddy covariance (EC) estimates of carbon dioxide (CO 2) fluxes and energy balance are examined to investigate the functional responses of a mature mangrove forest to a disturbance generated by Hurricane Wilma on October 24, 2005 in the Florida Everglades. At the EC site, high winds from the hurricane caused nearly 100% defoliation in the upper canopy and widespread tree mortality. Soil temperatures down to -50cm increased, and air temperature lapse rates within the forest canopy switched from statically stable to statically unstable conditions following the disturbance. Unstable conditions allowed more efficient transport of water vapor and CO 2 from the surface up to the upper canopy layer. Significant increases in latent heat fluxes (LE) and nighttime net ecosystem exchange (NEE) were also observed and sensible heat fluxes (H) as a proportion of net radiation decreased significantly in response to the disturbance. Many of these impacts persisted through much of the study period through 2009. However, local albedo and MODIS (Moderate Resolution Imaging Spectro-radiometer) data (the Enhanced Vegetation Index) indicated a substantial proportion of active leaf area recovered before the EC measurements began 1year after the storm. Observed changes in the vertical distribution and the degree of clumping in newly emerged leaves may have affected the energy balance. Direct comparisons of daytime NEE values from before the storm and after our measurements resumed did not show substantial or consistent differences that could be attributed to the disturbance. Regression analyses on seasonal time scales were required to differentiate the storm's impact on monthly average daytime NEE from the changes caused by interannual variability in other environmental drivers. The effects of the storm were apparent on annual time scales, and CO 2 uptake remained approximately 250gCm -2yr -1 lower in 2009 compared to the average annual values measured in 2004-2005. Dry season CO 2 uptake

  16. Long-term monitoring of Dzanga Bai forest elephants: forest clearing use patterns.

    PubMed

    Turkalo, Andrea K; Wrege, Peter H; Wittemyer, George

    2013-01-01

    Individual identification of the relatively cryptic forest elephant (Loxodonta cyclotis) at forest clearings currently provides the highest quality monitoring data on this ecologically important but increasingly threatened species. Here we present baseline data from the first 20 years of an individually based study of this species, conducted at the Dzanga Clearing, Central African Republic. A total of 3,128 elephants were identified over the 20-year study (1,244 adults; 675 females, 569 males). It took approximately four years for the majority of elephants visiting the clearing to be identified, but new elephants entered the clearing every year of the study. The study population was relatively stable, varying from 1,668 to 1,864 individuals (including juveniles and infants), with increasingly fewer males than females over time. The age-class distribution for females remained qualitatively unchanged between 1995 and 2010, while the proportion of adult males decreased from 20% to 10%, likely reflecting increased mortality. Visitation patterns by individuals were highly variable, with some elephants visiting monthly while others were ephemeral users with visits separated by multiple years. The number of individuals in the clearing at any time varied between 40 and 100 individuals, and there was little evidence of a seasonal pattern in this variation. The number of elephants entering the clearing together (defined here as a social group) averaged 1.49 (range 1-12) for males and 2.67 (range 1-14) for females. This collation of 20 years of intensive forest elephant monitoring provides the first detailed, long term look at the ecology of bai visitation for this species, offering insight to the ecological significance and motivation for bai use, social behavior, and threats to forest elephants. We discuss likely drivers (rainfall, compression, illegal killing, etc.) influencing bai visitation rates. This study provides the baseline for future demographic and behavioral

  17. Long-Term Monitoring of Dzanga Bai Forest Elephants: Forest Clearing Use Patterns

    PubMed Central

    Turkalo, Andrea K.; Wrege, Peter H.; Wittemyer, George

    2013-01-01

    Individual identification of the relatively cryptic forest elephant (Loxodonta cyclotis) at forest clearings currently provides the highest quality monitoring data on this ecologically important but increasingly threatened species. Here we present baseline data from the first 20 years of an individually based study of this species, conducted at the Dzanga Clearing, Central African Republic. A total of 3,128 elephants were identified over the 20-year study (1,244 adults; 675 females, 569 males). It took approximately four years for the majority of elephants visiting the clearing to be identified, but new elephants entered the clearing every year of the study. The study population was relatively stable, varying from 1,668 to 1,864 individuals (including juveniles and infants), with increasingly fewer males than females over time. The age-class distribution for females remained qualitatively unchanged between 1995 and 2010, while the proportion of adult males decreased from 20% to 10%, likely reflecting increased mortality. Visitation patterns by individuals were highly variable, with some elephants visiting monthly while others were ephemeral users with visits separated by multiple years. The number of individuals in the clearing at any time varied between 40 and 100 individuals, and there was little evidence of a seasonal pattern in this variation. The number of elephants entering the clearing together (defined here as a social group) averaged 1.49 (range 1–12) for males and 2.67 (range 1–14) for females. This collation of 20 years of intensive forest elephant monitoring provides the first detailed, long term look at the ecology of bai visitation for this species, offering insight to the ecological significance and motivation for bai use, social behavior, and threats to forest elephants. We discuss likely drivers (rainfall, compression, illegal killing, etc.) influencing bai visitation rates. This study provides the baseline for future demographic and behavioral

  18. Rates and drivers of mangrove deforestation in Southeast Asia, 2000-2012.

    PubMed

    Richards, Daniel R; Friess, Daniel A

    2016-01-12

    The mangrove forests of Southeast Asia are highly biodiverse and provide multiple ecosystem services upon which millions of people depend. Mangroves enhance fisheries and coastal protection, and store among the highest densities of carbon of any ecosystem globally. Mangrove forests have experienced extensive deforestation owing to global demand for commodities, and previous studies have identified the expansion of aquaculture as largely responsible. The proportional conversion of mangroves to different land use types has not been systematically quantified across Southeast Asia, however, particularly in recent years. In this study we apply a combined geographic information system and remote sensing method to quantify the key proximate drivers (i.e., replacement land uses) of mangrove deforestation in Southeast Asia between 2000 and 2012. Mangrove forests were lost at an average rate of 0.18% per year, which is lower than previously published estimates. In total, more than 100,000 ha of mangroves were removed during the study period, with aquaculture accounting for 30% of this total forest change. The rapid expansion of rice agriculture in Myanmar, and the sustained conversion of mangroves to oil palm plantations in Malaysia and Indonesia, are identified as additional increasing and under-recognized threats to mangrove ecosystems. Our study highlights frontiers of mangrove deforestation in the border states of Myanmar, on Borneo, and in Indonesian Papua. To implement policies that conserve mangrove forests across Southeast Asia, it is essential to consider the national and subnational variation in the land uses that follow deforestation. PMID:26712025

  19. Rates and drivers of mangrove deforestation in Southeast Asia, 2000-2012.

    PubMed

    Richards, Daniel R; Friess, Daniel A

    2016-01-12

    The mangrove forests of Southeast Asia are highly biodiverse and provide multiple ecosystem services upon which millions of people depend. Mangroves enhance fisheries and coastal protection, and store among the highest densities of carbon of any ecosystem globally. Mangrove forests have experienced extensive deforestation owing to global demand for commodities, and previous studies have identified the expansion of aquaculture as largely responsible. The proportional conversion of mangroves to different land use types has not been systematically quantified across Southeast Asia, however, particularly in recent years. In this study we apply a combined geographic information system and remote sensing method to quantify the key proximate drivers (i.e., replacement land uses) of mangrove deforestation in Southeast Asia between 2000 and 2012. Mangrove forests were lost at an average rate of 0.18% per year, which is lower than previously published estimates. In total, more than 100,000 ha of mangroves were removed during the study period, with aquaculture accounting for 30% of this total forest change. The rapid expansion of rice agriculture in Myanmar, and the sustained conversion of mangroves to oil palm plantations in Malaysia and Indonesia, are identified as additional increasing and under-recognized threats to mangrove ecosystems. Our study highlights frontiers of mangrove deforestation in the border states of Myanmar, on Borneo, and in Indonesian Papua. To implement policies that conserve mangrove forests across Southeast Asia, it is essential to consider the national and subnational variation in the land uses that follow deforestation.

  20. Rates and drivers of mangrove deforestation in Southeast Asia, 2000–2012

    PubMed Central

    Richards, Daniel R.; Friess, Daniel A.

    2016-01-01

    The mangrove forests of Southeast Asia are highly biodiverse and provide multiple ecosystem services upon which millions of people depend. Mangroves enhance fisheries and coastal protection, and store among the highest densities of carbon of any ecosystem globally. Mangrove forests have experienced extensive deforestation owing to global demand for commodities, and previous studies have identified the expansion of aquaculture as largely responsible. The proportional conversion of mangroves to different land use types has not been systematically quantified across Southeast Asia, however, particularly in recent years. In this study we apply a combined geographic information system and remote sensing method to quantify the key proximate drivers (i.e., replacement land uses) of mangrove deforestation in Southeast Asia between 2000 and 2012. Mangrove forests were lost at an average rate of 0.18% per year, which is lower than previously published estimates. In total, more than 100,000 ha of mangroves were removed during the study period, with aquaculture accounting for 30% of this total forest change. The rapid expansion of rice agriculture in Myanmar, and the sustained conversion of mangroves to oil palm plantations in Malaysia and Indonesia, are identified as additional increasing and under-recognized threats to mangrove ecosystems. Our study highlights frontiers of mangrove deforestation in the border states of Myanmar, on Borneo, and in Indonesian Papua. To implement policies that conserve mangrove forests across Southeast Asia, it is essential to consider the national and subnational variation in the land uses that follow deforestation. PMID:26712025

  1. Monitoring of impact of anthropogenic inputs on water quality of mangrove ecosystem of Uran, Navi Mumbai, west coast of India.

    PubMed

    Pawar, Prabhakar R

    2013-10-15

    Surface water samples were collected from substations along Sheva creek and Dharamtar creek mangrove ecosystems of Uran (Raigad), Navi Mumbai, west coast of India. Water samples were collected fortnightly from April 2009 to March 2011 during spring low and high tides and were analyzed for pH, Temperature, Turbidity, Total solids (TS), Total dissolved solids (TDS), Total suspended solids (TSS), Dissolved oxygen (DO), Biochemical oxygen demand (BOD), Carbon dioxide (CO2), Chemical oxygen demand (COD), Salinity, Orthophosphate (O-PO4), Nitrite-nitrogen (NO2-N), Nitrate-nitrogen (NO3-N), and Silicates. Variables like pH, turbidity, TDS, salinity, DO, and BOD show seasonal variations. Higher content of O-PO4, NO3-N, and silicates is recorded due to discharge of domestic wastes and sewage, effluents from industries, oil tanking depots and also from maritime activities of Jawaharlal Nehru Port Trust (JNPT), hectic activities of Container Freight Stations (CFS), and other port wastes. This study reveals that water quality from mangrove ecosystems of Uran is deteriorating due to industrial pollution and that mangrove from Uran is facing the threat due to anthropogenic stress. PMID:23856298

  2. Wind damage effects of Hurricane Andrew on mangrove communities along the southwest coast of Florida, USA

    USGS Publications Warehouse

    Doyle, T.W.; Smith, T. J.; Robblee, M.B.

    1995-01-01

    On August 24, 1992, Hurricane Andrew downed and defoliated an extensive swath of mangrove trees across the lower Florida peninsula. Permanent field sites were established to assess the extent of forest damage and to monitor the rate and process of forest recovery. Canopy trees suffered the highest mortality particularly for sites within and immediately north of the storm's eyewall. The type and extent of site damage, windthrow, branch loss, and defoliation generally decreased exponentially with increasing distance from the storm track. Forest damage was greater for sites in the storm's right quadrant than in the left quadrant tor the same given distance from the storm center. Stand exposure, both horizontally and vertically, increased the susceptibility and probability of forest damage and accounted for much of the local variability. Slight species differences were found. Laguncularia racemosa exceeded Avicennia germinans and Rhizophora mangle in damage tendency under similar wind conditions. Azimuths of downed trees were strongly correlated with maximum wind speed and vector based on a hurricane simulation of the storm. Lateral branch loss and leaf defoliation on sites without windthrow damage indicated a degree of crown thinning and light penetration equivalent to treefall gaps under normally intact forest conditions. Mangrove species and forests are susceptible to catastrophic disturbance by hurricanes; the impacts of which are significant to changes in forest structure and function.

  3. Hurricane disturbance and recovery of energy balance, CO2 fluxes and canopy structure in a mangrove forest of the Florida Everglades

    USGS Publications Warehouse

    Barr, Jordan G.; Engel, Vic; Smith, Thomas J.; Fuentes, Jose D.

    2012-01-01

    Eddy covariance (EC) estimates of carbon dioxide (CO2) fluxes and energy balance are examined to investigate the functional responses of a mature mangrove forest to a disturbance generated by Hurricane Wilma on October 24, 2005 in the Florida Everglades. At the EC site, high winds from the hurricane caused nearly 100% defoliation in the upper canopy and widespread tree mortality. Soil temperatures down to -50 cm increased, and air temperature lapse rates within the forest canopy switched from statically stable to statically unstable conditions following the disturbance. Unstable conditions allowed more efficient transport of water vapor and CO2 from the surface up to the upper canopy layer. Significant increases in latent heat fluxes (LE) and nighttime net ecosystem exchange (NEE) were also observed and sensible heat fluxes (H) as a proportion of net radiation decreased significantly in response to the disturbance. Many of these impacts persisted through much of the study period through 2009. However, local albedo and MODIS (Moderate Resolution Imaging Spectro-radiometer) data (the Enhanced Vegetation Index) indicated a substantial proportion of active leaf area recovered before the EC measurements began 1 year after the storm. Observed changes in the vertical distribution and the degree of clumping in newly emerged leaves may have affected the energy balance. Direct comparisons of daytime NEE values from before the storm and after our measurements resumed did not show substantial or consistent differences that could be attributed to the disturbance. Regression analyses on seasonal time scales were required to differentiate the storm's impact on monthly average daytime NEE from the changes caused by interannual variability in other environmental drivers. The effects of the storm were apparent on annual time scales, and CO2 uptake remained approximately 250 g C m-2 yr-1 lower in 2009 compared to the average annual values measured in 2004–2005. Dry season CO2

  4. BIRD COMMUNITIES AND HABITAT AS ECOLOGICAL INDICATORS OF FOREST CONDITION IN REGIONAL MONITORING

    EPA Science Inventory

    Ecological indicators for long-term monitoring programs are needed to detect and assess changing environmental conditions, We developed and tested community-level environmental indicators for monitoring forest bird populations and associated habitat. We surveyed 197 sampling plo...

  5. Feeding ecology of chimpanzees (Pan troglodytes verus) inhabiting a forest-mangrove-savanna-agricultural matrix at Caiquene-Cadique, Cantanhez National Park, Guinea-Bissau.

    PubMed

    Bessa, Joana; Sousa, Cláudia; Hockings, Kimberley J

    2015-06-01

    With rising conversion of "natural" habitat to other land use such as agriculture, nonhuman primates are increasingly exploiting areas influenced by people and their activities. Despite the conservation importance of understanding the ways in which primates modify their behavior to human pressures, data are lacking, even for well-studied species. Using systematically collected data (fecal samples, feeding traces, and direct observations), we examined the diet and feeding strategies of an unhabituated chimpanzee community (Pan troglodytes verus) at Caiquene-Cadique in Guinea-Bissau that inhabit a forest-savanna-mangrove-agricultural mosaic. The chimpanzees experienced marked seasonal variations in the availability of plant foods, but maintained a high proportion of ripe fruit in the diet across months. Certain wild species were identified as important to this community including oil-palm (Elaeis guineensis) fruit and flower. Honey was frequently consumed but no other insects or vertebrates were confirmed to be eaten by this community. However, we provide indirect evidence of possible smashing and consumption of giant African snails (Achatina sp.) by chimpanzees at this site. Caiquene-Cadique chimpanzees were confirmed to feed on nine different agricultural crops, which represented 13.6% of all plant species consumed. Consumption of fruit and nonfruit crops was regular, but did not increase during periods of wild fruit scarcity. Crop consumption is an increasing and potentially problematic behavior, which can impact local people's tolerance toward wildlife. To maximize the potential success of any human-wildlife coexistence strategy (e.g., to reduce primate crop feeding), knowledge of primate behavior, as well as multifaceted social dimensions of interactions, is critical. PMID:25800459

  6. Coastal resource degradation in the tropics: does the tragedy of the commons apply for coral reefs, mangrove forests and seagrass beds.

    PubMed

    Wilkinson, Clive; Salvat, Bernard

    2012-06-01

    The keynote paper by Garrett Hardin 44 years ago introduced the term 'tragedy of the commons' into our language (Hardin, 1968); this term is now used widely, but it is neither universally accepted nor fully understood. Irrespective, the 'tragedy of the commons' is an increasing reality for more than 500 million people that rely on the biodiversity resources and services of tropical coral reefs, mangrove forests, seagrass beds and associated fisheries. These natural resources continue to decline despite major advances in our scientific understanding of how ecosystems and human populations interact, and the application of considerable conservation and management efforts at scales from local user communities to oceans. Greater effort will be required to avert increasing damage from over-exploitation, pollution and global climate change; all deriving from increasing exploitation driven by poverty and progress i.e. continuing to expand development indefinitely and extraction of resources at industrial scales. However, the 'tragedy' concept has been widely criticized as a simple metaphor for a much larger set of problems and solutions. We argue that the 'tragedy' is essentially real and will continue to threaten the lives of millions of people unless there are some major moral and policy shifts to reverse increasing damage to coastal habitats and resources. We agree with the conclusion by Hardin that the solution to the tragedy will not be through the application of natural sciences, but via implementing exceedingly difficult and controversial moral decisions. An extreme example of a moral and controversial direction suggested by Hardin was in re-examining the 'freedom to breed' as an inherent human value. The need for 'moral decisions' is even greater in 2012. PMID:22349467

  7. Coastal resource degradation in the tropics: does the tragedy of the commons apply for coral reefs, mangrove forests and seagrass beds.

    PubMed

    Wilkinson, Clive; Salvat, Bernard

    2012-06-01

    The keynote paper by Garrett Hardin 44 years ago introduced the term 'tragedy of the commons' into our language (Hardin, 1968); this term is now used widely, but it is neither universally accepted nor fully understood. Irrespective, the 'tragedy of the commons' is an increasing reality for more than 500 million people that rely on the biodiversity resources and services of tropical coral reefs, mangrove forests, seagrass beds and associated fisheries. These natural resources continue to decline despite major advances in our scientific understanding of how ecosystems and human populations interact, and the application of considerable conservation and management efforts at scales from local user communities to oceans. Greater effort will be required to avert increasing damage from over-exploitation, pollution and global climate change; all deriving from increasing exploitation driven by poverty and progress i.e. continuing to expand development indefinitely and extraction of resources at industrial scales. However, the 'tragedy' concept has been widely criticized as a simple metaphor for a much larger set of problems and solutions. We argue that the 'tragedy' is essentially real and will continue to threaten the lives of millions of people unless there are some major moral and policy shifts to reverse increasing damage to coastal habitats and resources. We agree with the conclusion by Hardin that the solution to the tragedy will not be through the application of natural sciences, but via implementing exceedingly difficult and controversial moral decisions. An extreme example of a moral and controversial direction suggested by Hardin was in re-examining the 'freedom to breed' as an inherent human value. The need for 'moral decisions' is even greater in 2012.

  8. Feeding ecology of chimpanzees (Pan troglodytes verus) inhabiting a forest-mangrove-savanna-agricultural matrix at Caiquene-Cadique, Cantanhez National Park, Guinea-Bissau.

    PubMed

    Bessa, Joana; Sousa, Cláudia; Hockings, Kimberley J

    2015-06-01

    With rising conversion of "natural" habitat to other land use such as agriculture, nonhuman primates are increasingly exploiting areas influenced by people and their activities. Despite the conservation importance of understanding the ways in which primates modify their behavior to human pressures, data are lacking, even for well-studied species. Using systematically collected data (fecal samples, feeding traces, and direct observations), we examined the diet and feeding strategies of an unhabituated chimpanzee community (Pan troglodytes verus) at Caiquene-Cadique in Guinea-Bissau that inhabit a forest-savanna-mangrove-agricultural mosaic. The chimpanzees experienced marked seasonal variations in the availability of plant foods, but maintained a high proportion of ripe fruit in the diet across months. Certain wild species were identified as important to this community including oil-palm (Elaeis guineensis) fruit and flower. Honey was frequently consumed but no other insects or vertebrates were confirmed to be eaten by this community. However, we provide indirect evidence of possible smashing and consumption of giant African snails (Achatina sp.) by chimpanzees at this site. Caiquene-Cadique chimpanzees were confirmed to feed on nine different agricultural crops, which represented 13.6% of all plant species consumed. Consumption of fruit and nonfruit crops was regular, but did not increase during periods of wild fruit scarcity. Crop consumption is an increasing and potentially problematic behavior, which can impact local people's tolerance toward wildlife. To maximize the potential success of any human-wildlife coexistence strategy (e.g., to reduce primate crop feeding), knowledge of primate behavior, as well as multifaceted social dimensions of interactions, is critical.

  9. Nutrient controls on biocomplexity of mangrove ecosystems

    USGS Publications Warehouse

    McKee, Karen L.

    2004-01-01

    Mangrove forests are important coastal ecosystems that provide a variety of ecological and societal services. These intertidal, tree-dominated communities along tropical coastlines are often described as “simple systems,” compared to other tropical forests with larger numbers of plant species and multiple understory strata; however, mangrove ecosystems have complex trophic structures, and organisms exhibit unique physiological, morphological, and behavioral adaptations to environmental conditions characteristic of the land-sea interface. Biogeochemical functioning of mangrove forests is also controlled by interactions among the microbial, plant, and animal communities and feedback linkages mediated by hydrology and other forcing functions. Scientists with the U.S. Geological Survey (USGS) at the National Wetlands Research Center are working to understand more fully the impact of nutrient variability on these delicate and important ecosystems.

  10. The Shoreline Video Assessment Method (S-VAM): Using dynamic hyperlapse image acquisition to evaluate shoreline mangrove forest structure, values, degradation and threats.

    PubMed

    Mackenzie, Jock R; Duke, Norman C; Wood, Apanie L

    2016-08-30

    Climate change with human direct pressures represent significant threats to the resilience of shoreline habitats like mangroves. A rapid, whole-of-system assessment strategy is needed to evaluate such threats, better linking innovative remote sensing with essential on-ground evaluations. Using the Shoreline Video Assessment Method, we surveyed around 190km of the mostly mangrove-fringed (78%) coastline of Kien Giang Province, Vietnam. The aim was to identify anthropogenic drivers of degradation, establishing baseline for specific rehabilitation and protection strategies. Fish traps occupy at least 87% of shoreline mangroves, around which there were abundant human activities - like fishing, crabbing, farming, plus collecting firewood and foliage. Such livelihoods were associated with remnant, fringing mangrove that were largely degraded and threatened by erosion retreat, herbivory, and excessive cutting. Our assessment quantified associated threats to shoreline stability, along with previous rehabilitation intervention measures. The method offers key opportunities for effective conservation and management of vulnerable shoreline habitats. PMID:27293078

  11. Forest Carbon Monitoring and Reporting for REDD+: What Future for Africa?

    NASA Astrophysics Data System (ADS)

    Gizachew, Belachew; Duguma, Lalisa A.

    2016-11-01

    A climate change mitigation mechanism for emissions reduction from reduced deforestation and forest degradation, plus forest conservation, sustainable management of forest, and enhancement of carbon stocks (REDD+), has received an international political support in the climate change negotiations. The mechanism will require, among others, an unprecedented technical capacity for monitoring, reporting and verification of carbon emissions from the forest sector. A functional monitoring, reporting and verification requires inventories of forest area, carbon stock and changes, both for the construction of forest reference emissions level and compiling the report on the actual emissions, which are essentially lacking in developing countries, particularly in Africa. The purpose of this essay is to contribute to a better understanding of the state and prospects of forest monitoring and reporting in the context of REDD+ in Africa. We argue that monitoring and reporting capacities in Africa fall short of the stringent requirements of the methodological guidance for monitoring, reporting and verification for REDD+, and this may weaken the prospects for successfully implementing REDD+ in the continent. We presented the challenges and prospects in the national forest inventory, remote sensing and reporting infrastructures. A North-South, South-South collaboration as well as governments own investments in monitoring, reporting and verification system could help Africa leapfrog in monitoring and reporting. These could be delivered through negotiations for the transfer of technology, technical capacities, and experiences that exist among developed countries that traditionally compile forest carbon reports in the context of the Kyoto protocol.

  12. Bacterial N2-fixation in mangrove ecosystems: insights from a diazotroph-mangrove interaction.

    PubMed

    Alfaro-Espinoza, Gabriela; Ullrich, Matthias S

    2015-01-01

    Mangrove forests are highly productive ecosystems but represent low nutrient environments. Nitrogen availability is one of the main factors limiting mangrove growth. Diazotrophs have been identified as key organisms that provide nitrogen to these environments. N2-fixation by such organisms was found to be higher in the mangrove roots than in surrounding rhizosphere. Moreover, previous studies showed that mangroves grew better in the presence of N2-fixers indicating a potentially mutualistic relationship. However, the molecular signals and mechanisms that govern these interactions are still poorly understood. Here we present novel insights in the interaction of a diazotroph with a mangrove species to improve our understanding of the molecular and ecophysiological relationship between these two organisms under controlled conditions. Our results showed that Marinobacterium mangrovicola is a versatile organism capable of competing with other organisms to survive for long periods in mangrove soils. N2-fixation by this bacterium was up-regulated in the presence of mangrove roots, indicating a possible beneficial interaction. The increase in N2-fixation was limited to cells of the exponential growth phase suggesting that N2-fixation differs over the bacterial growth cycle. Bacterial transformants harboring a transcriptional nifH::gusA fusion showed that M. mangrovicola successfully colonized mangrove roots and simultaneously conducted N2-fixation. The colonization process was stimulated by the lack of an external carbon source suggesting a possible mutualistic relationship. M. mangrovicola represents an interesting genetically accessible diazotroph, which colonize mangrove roots and exhibit higher N2-fixation in the presence of mangrove roots. Consequently, we propose this microorganism as a tool to study molecular interactions between N2-fixers and mangrove plants and to better understand how changes in the environment could impact these important and relatively unknown

  13. Bacterial N2-fixation in mangrove ecosystems: insights from a diazotroph–mangrove interaction

    PubMed Central

    Alfaro-Espinoza, Gabriela; Ullrich, Matthias S.

    2015-01-01

    Mangrove forests are highly productive ecosystems but represent low nutrient environments. Nitrogen availability is one of the main factors limiting mangrove growth. Diazotrophs have been identified as key organisms that provide nitrogen to these environments. N2-fixation by such organisms was found to be higher in the mangrove roots than in surrounding rhizosphere. Moreover, previous studies showed that mangroves grew better in the presence of N2-fixers indicating a potentially mutualistic relationship. However, the molecular signals and mechanisms that govern these interactions are still poorly understood. Here we present novel insights in the interaction of a diazotroph with a mangrove species to improve our understanding of the molecular and ecophysiological relationship between these two organisms under controlled conditions. Our results showed that Marinobacterium mangrovicola is a versatile organism capable of competing with other organisms to survive for long periods in mangrove soils. N2-fixation by this bacterium was up-regulated in the presence of mangrove roots, indicating a possible beneficial interaction. The increase in N2-fixation was limited to cells of the exponential growth phase suggesting that N2-fixation differs over the bacterial growth cycle. Bacterial transformants harboring a transcriptional nifH::gusA fusion showed that M. mangrovicola successfully colonized mangrove roots and simultaneously conducted N2-fixation. The colonization process was stimulated by the lack of an external carbon source suggesting a possible mutualistic relationship. M. mangrovicola represents an interesting genetically accessible diazotroph, which colonize mangrove roots and exhibit higher N2-fixation in the presence of mangrove roots. Consequently, we propose this microorganism as a tool to study molecular interactions between N2-fixers and mangrove plants and to better understand how changes in the environment could impact these important and relatively unknown

  14. Use of Multi-Year MODIS Phenological Data Products to Detect and Monitor Forest Disturbances at Regional and National Scales

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Hargrove, William W.; Gasser, Jerry; Smoot, James; Ross, Kenton

    2010-01-01

    This presentation discusses an effort to use select MODIS phenological products for forest disturbance monitoring at the regional and CONUS scales. Forests occur on 1/3 of the U.S. land base and include regionally prevalent forest disturbances that can threaten forest sustainability. Regional and CONUS forest disturbance monitoring is needed for a national forest threat early warning system being developed by the USDA Forest Service with help from NASA, ORNL, and USGS. MODIS NDVI phenology products are being used to develop forest disturbance monitoring capabilities of this EWS.

  15. Saltmarsh boundary modulates dispersal of mangrove propagules: implications for mangrove migration with sea-level rise.

    PubMed

    Peterson, Jennifer M; Bell, Susan S

    2015-01-01

    Few studies have empirically examined the suite of mechanisms that underlie the distributional shifts displayed by organisms in response to changing climatic condition. Mangrove forests are expected to move inland as sea-level rises, encroaching on saltmarsh plants inhabiting higher elevations. Mangrove propagules are transported by tidal waters and propagule dispersal is likely modified upon encountering the mangrove-saltmarsh ecotone, the implications of which are poorly known. Here, using an experimental approach, we record landward and seaward dispersal and subsequent establishment of mangrove propagules that encounter biotic boundaries composed of two types of saltmarsh taxa: succulents and grasses. Our findings revealed that propagules emplaced within saltmarsh vegetation immediately landward of the extant mangrove fringe boundary frequently dispersed in the seaward direction. However, propagules moved seaward less frequently and over shorter distances upon encountering boundaries composed of saltmarsh grasses versus succulents. We uniquely confirmed that the small subset of propagules dispersing landward displayed proportionately higher establishment success than those transported seaward. Although impacts of ecotones on plant dispersal have rarely been investigated in situ, our experimental results indicate that the interplay between tidal transport and physical attributes of saltmarsh vegetation influence boundary permeability to propagules, thereby directing the initial phase of shifting mangrove distributions. The incorporation of tidal inundation information and detailed data on landscape features, such as the structure of saltmarsh vegetation at mangrove boundaries, should improve the accuracy of models that are being developed to forecast mangrove distributional shifts in response to sea-level rise. PMID:25760867

  16. Saltmarsh boundary modulates dispersal of mangrove propagules: implications for mangrove migration with sea-level rise.

    PubMed

    Peterson, Jennifer M; Bell, Susan S

    2015-01-01

    Few studies have empirically examined the suite of mechanisms that underlie the distributional shifts displayed by organisms in response to changing climatic condition. Mangrove forests are expected to move inland as sea-level rises, encroaching on saltmarsh plants inhabiting higher elevations. Mangrove propagules are transported by tidal waters and propagule dispersal is likely modified upon encountering the mangrove-saltmarsh ecotone, the implications of which are poorly known. Here, using an experimental approach, we record landward and seaward dispersal and subsequent establishment of mangrove propagules that encounter biotic boundaries composed of two types of saltmarsh taxa: succulents and grasses. Our findings revealed that propagules emplaced within saltmarsh vegetation immediately landward of the extant mangrove fringe boundary frequently dispersed in the seaward direction. However, propagules moved seaward less frequently and over shorter distances upon encountering boundaries composed of saltmarsh grasses versus succulents. We uniquely confirmed that the small subset of propagules dispersing landward displayed proportionately higher establishment success than those transported seaward. Although impacts of ecotones on plant dispersal have rarely been investigated in situ, our experimental results indicate that the interplay between tidal transport and physical attributes of saltmarsh vegetation influence boundary permeability to propagules, thereby directing the initial phase of shifting mangrove distributions. The incorporation of tidal inundation information and detailed data on landscape features, such as the structure of saltmarsh vegetation at mangrove boundaries, should improve the accuracy of models that are being developed to forecast mangrove distributional shifts in response to sea-level rise.

  17. Saltmarsh Boundary Modulates Dispersal of Mangrove Propagules: Implications for Mangrove Migration with Sea-Level Rise

    PubMed Central

    Peterson, Jennifer M.; Bell, Susan S.

    2015-01-01

    Few studies have empirically examined the suite of mechanisms that underlie the distributional shifts displayed by organisms in response to changing climatic condition. Mangrove forests are expected to move inland as sea-level rises, encroaching on saltmarsh plants inhabiting higher elevations. Mangrove propagules are transported by tidal waters and propagule dispersal is likely modified upon encountering the mangrove-saltmarsh ecotone, the implications of which are poorly known. Here, using an experimental approach, we record landward and seaward dispersal and subsequent establishment of mangrove propagules that encounter biotic boundaries composed of two types of saltmarsh taxa: succulents and grasses. Our findings revealed that propagules emplaced within saltmarsh vegetation immediately landward of the extant mangrove fringe boundary frequently dispersed in the seaward direction. However, propagules moved seaward less frequently and over shorter distances upon encountering boundaries composed of saltmarsh grasses versus succulents. We uniquely confirmed that the small subset of propagules dispersing landward displayed proportionately higher establishment success than those transported seaward. Although impacts of ecotones on plant dispersal have rarely been investigated in situ, our experimental results indicate that the interplay between tidal transport and physical attributes of saltmarsh vegetation influence boundary permeability to propagules, thereby directing the initial phase of shifting mangrove distributions. The incorporation of tidal inundation information and detailed data on landscape features, such as the structure of saltmarsh vegetation at mangrove boundaries, should improve the accuracy of models that are being developed to forecast mangrove distributional shifts in response to sea-level rise. PMID:25760867

  18. NASA LCLUC Program: An Integrated Forest Monitoring System for Central Africa

    NASA Technical Reports Server (NTRS)

    Laporte, Nadine; LeMoigne, Jacqueline; Elkan, Paul; Desmet, Olivier; Paget, Dominique; Pumptre, Andrew; Gouala, Patrice; Honzack, Miro; Maisels, Fiona

    2004-01-01

    Central Africa has the second largest unfragmented block of tropical rain forest in the world; it is also one of the largest carbon and biodiversity reservoirs. With nearly one-third of the forest currently allocated for logging, the region is poised to undergo extensive land-use change. Through the mapping of the forests, our Integrated Forest Monitoring System for Central Africa (INFORMS) project aims to monitor habitat alteration, support biodiversity conservation, and promote better land-use planning and forest management. Designed as an interdisciplinary project, its goal is to integrate data acquired from satellites with field observations from forest inventories, wildlife surveys, and socio-economic studies to map and monitor forest resources. This project also emphasizes on collaboration and coordination with international, regional, national, and local partners-including non-profit, governmental, and commercial sectors. This project has been focused on developing remote sensing products for the needs of forest conservation and management, insuring that research findings are incorporated in forest management plans at the national level. The societal impact of INFORMS can be also appreciated through the development of a regional remote sensing network in central Africa. With a regional office in Kinshasa, (www.OSFAC.org), the contribution to the development of forest management plans for 1.5 million hectares of forests in northern Republic of Congo (www.tt-timber.com), and the monitoring of park encroachments in the Albertine region (Uganda and DRC) (www.albertinerift.org).

  19. The physiology of mangrove trees with changing climate

    USGS Publications Warehouse

    Lovelock, Catherine E.; Krauss, Ken W.; Osland, Michael J.; Reef, Ruth; Ball, Marilyn C.; Meinzer, Frederick C.; Niinemets, Ülo

    2016-01-01

    Mangrove forests grow on saline, periodically flooded soils of the tropical and subtropical coasts. The tree species that comprise the mangrove are halophytes that have suites of traits that confer differing levels of tolerance of salinity, aridity, inundation and extremes of temperature. Here we review how climate change and elevated levels of atmospheric CO2 will influence mangrove forests. Tolerance of salinity and inundation in mangroves is associated with the efficient use of water for photosynthetic carbon gain which unpins anticipated gains in productivity with increasing levels of CO2. We review evidence of increases in productivity with increasing CO2, finding that enhancements in growth appear to be similar to trees in non-mangrove habitats and that gains in productivity with elevated CO2 are likely due to changes in biomass allocation. High levels of trait plasticity are observed in some mangrove species, which potentially facilitates their responses to climate change. Trait plasticity is associated with broad tolerance of salinity, aridity, low temperatures and nutrient availability. Because low temperatures and aridity place strong limits on mangrove growth at the edge of their current distribution, increasing temperatures over time and changing rainfall patterns are likely to have an important influence on the distribution of mangroves. We provide a global analysis based on plant traits and IPCC scenarios of changing temperature and aridity that indicates substantial global potential for mangrove expansion.

  20. Habitat monitoring and genotoxicity in Ucides cordatus (Crustacea: Ucididae), as tools to manage a mangrove reserve in southeastern Brazil.

    PubMed

    Pinheiro, M A A; Duarte, L F A; Toledo, T R; Adam, M L; Torres, R A

    2013-10-01

    In Brazil, the state of São Paulo contains both preserved areas (Juréia-Itatins Ecological Station) and extremely impacted ones (Cubatão Municipality). This study evaluated the concentrations of five metals (Cu, Cd, Cr, Pb, and Hg) in two mangroves with different levels of anthropogenic impact and the apparent genotoxicity to Ucides cordatus. Water and sediment samples were obtained, and metal concentrations were determined with an atomic absorption spectrophotometer. The genotoxic impact was quantified based on the number of micronucleated cells per 1,000 analyzed (MN‰), using hemolymph slides stained with Giemsa. Metal concentrations in water were below the detection limit, except for lead, although no significant difference was observed between the areas (P > 0.05). Sediment from Cubatão had higher concentrations of Cd, Pb, Cr, and Cu than sediment from Juréia-Itatins (P < 0.05), but no significant differences in metal concentrations were detected among depth strata of the sediment (P > 0.05). Crabs from Cubatão had a 2.6 times higher mean frequency of micronucleated cells (5.2 ± 1.8 MN‰) than those from Juréia-Itatins (2.0 ± 1.0 MN‰; P < 0.0001). The more-polluted conditions found in the mangrove sediments of Cubatão were reflected in the micronucleus assay, demonstrating their genotoxic effect; however, genetic damage should be attributed to a synergistic effect with other kinds of pollutants previously recorded in different environments of Cubatão. U. cordatus proved to be an excellent bioindicator of mangrove pollution. This study established, for the first time, the normal frequency of MN‰ in a population of this species within an ecological station. PMID:23584824

  1. Advancing Indonesian forest resource monitoring using multi-source remotely sensed imagery

    NASA Astrophysics Data System (ADS)

    Margono, B. A.; Turubanova, S.; Potapov, P.; Hansen, M.

    2013-12-01

    Indonesia experiences the third highest rate of deforestation among tropical countries (FAO, 2005, 2010, Hansen et al 2008, 2009). Providing timely and accurate forest data at the national scale is crucial to combat deforestation and forest degradation in support climate change mitigation and biodiversity conservation policy initiatives. Indonesia's national communication to the United Nations Framework on Climate Change (UNFCCC) in 2009 reveals a substantial role of forests as well as peatlands in contributing projected national carbon emission under business as usual. Further, in 2009 the government of Indonesia pledged to reduce national carbon emissions from between 26% to 41% of business as usual by 2020 while maintaining annual economic growth at 7%. The forests and wetlands therefore are becoming major interest for climate change mitigation in Indonesia. Our work here documents timely natural primary forests extent and loss within various types of physiographical formations. We present a hybrid approach to quantify the extent and change of primary forests for different composition and structure using a per-pixel supervised classification mapping combined with a GIS-based fragmentation analysis (Margono et al 2012). We also demonstrate the mapping of Indonesia's wetlands cover as a single thematic class (including peatlands, freshwater wetlands and mangroves) using topographical indices (derived from SRTM elevation data) combined with optical (Landsat) and radar (ALOS PALSAR) image data. We provided analysis within different physiographic formations (uplands and lowlands) defined using DEM data. The loss of Indonesia's primary intact and primary degraded forests, within wetlands and non-wetlands covers, as well as in the upland was quantified to provide suitable information for the objectives of the UNFCCC Reducing Emission from Deforestation and Forest Degradation (REDD and REDD+) program.

  2. Upstream petroleum degradation of mangroves and intertidal shores: the Niger Delta experience.

    PubMed

    Osuji, Leo C; Erondu, Ebere S; Ogali, Regina E

    2010-01-01

    This article was inspired by a field reconnaissance survey of outcrops along the Nembe-Brass axis of the petroliferous Niger Delta. It reviews various tradeoffs of the impact of upstream petroleum (seismic and production) operations on the mangrove ecosystems in that region, the largest in Sub-Saharan Africa. Mangroves and intertidal shores are considered critical to the economic well-being of this region owing to the people's dual occupation in fishing and farming. The mangrove ecosystem provides a nutrient medium, which serves as a nursery and spawning ground for many fish species and other biota. Oil and gas activities might destroy these spawn areas, causing reduction in resource output and community pressure. Devegetation of the mangrove forest as a result of seismic delineation leaves the fragile soil exposed, unprotected, and susceptible to erosion. Again, loss of vegetation might discourage the natural role of plants in air purification (CO(2) utilization and O(2) production). The release of nutrients (organic N(2), NH(3), and NO$\\rm{{_{3};{-}}}$) and polyaromatic hydrocarbons (PAHs) to the environment, with the attendant increase in microbial load, increases biochemical O(2) demand (BOD) and depletes dissolved O(2) (DO) in H(2)O to a level that is beyond the tolerance limit of organisms. This anoxic situation leads to asphyxiation and subsequent fish kill in affected areas. In order of increasing vulnerability, the mangroves and intertidal shores of the Niger Delta fall under categories 8 to 10 on the environmental sensitivity index (ESI) scale, which predisposes the areas to serious long-term effects and clean-up complexity. Thus, there is need to monitor mangrove systems and shoreline changes in the areas of considerable seismic and production activities, especially in the coastal Niger Delta, where pipeline corrosion due to salt intrusion into the swampy environment and 'unsighted fingers' of sabotage have increased the prevalence of oil spills. PMID

  3. Upstream petroleum degradation of mangroves and intertidal shores: the Niger Delta experience.

    PubMed

    Osuji, Leo C; Erondu, Ebere S; Ogali, Regina E

    2010-01-01

    This article was inspired by a field reconnaissance survey of outcrops along the Nembe-Brass axis of the petroliferous Niger Delta. It reviews various tradeoffs of the impact of upstream petroleum (seismic and production) operations on the mangrove ecosystems in that region, the largest in Sub-Saharan Africa. Mangroves and intertidal shores are considered critical to the economic well-being of this region owing to the people's dual occupation in fishing and farming. The mangrove ecosystem provides a nutrient medium, which serves as a nursery and spawning ground for many fish species and other biota. Oil and gas activities might destroy these spawn areas, causing reduction in resource output and community pressure. Devegetation of the mangrove forest as a result of seismic delineation leaves the fragile soil exposed, unprotected, and susceptible to erosion. Again, loss of vegetation might discourage the natural role of plants in air purification (CO(2) utilization and O(2) production). The release of nutrients (organic N(2), NH(3), and NO$\\rm{{_{3};{-}}}$) and polyaromatic hydrocarbons (PAHs) to the environment, with the attendant increase in microbial load, increases biochemical O(2) demand (BOD) and depletes dissolved O(2) (DO) in H(2)O to a level that is beyond the tolerance limit of organisms. This anoxic situation leads to asphyxiation and subsequent fish kill in affected areas. In order of increasing vulnerability, the mangroves and intertidal shores of the Niger Delta fall under categories 8 to 10 on the environmental sensitivity index (ESI) scale, which predisposes the areas to serious long-term effects and clean-up complexity. Thus, there is need to monitor mangrove systems and shoreline changes in the areas of considerable seismic and production activities, especially in the coastal Niger Delta, where pipeline corrosion due to salt intrusion into the swampy environment and 'unsighted fingers' of sabotage have increased the prevalence of oil spills.

  4. Mangrove Colonization: Mangrove Progression Over the Growing Pak Phanang (SE Thailand) Mud Flat

    NASA Astrophysics Data System (ADS)

    Panapitukkul, N.; Duarte, C. M.; Thampanya, U.; Kheowvongsri, P.; Srichai, N.; Geertz-Hansen, O.; Terrados, J.; Boromthanarath, S.

    1998-07-01

    A combination of remote sensing techniques and in situmeasurements along a chronosequence was used to elucidate the rate of progression of the mangrove forest in the Pak Phanang Bay (SE Thailand), a large bay with an extended and rapidly accreting mud flat. The examination of black and white aerial photographs of the forest in 1966, 1974, 1989 and 1995, and satellite images in 1985, 1990 and 1994 revealed that the mangrove forest located in the eastern bank of the bay was progressing over the mud flat. The rate of progression was estimated, from examination of changes in the position of the forest edge with time in the series of images, to average 38·6 m year -1over the 28-year interval encompassed by the images. Mangrove progression rates were fastest between 1966 and 1974 and slowest between 1974 and 1985, remaining uniform at about 30 m year -1thereafter. The in situexamination of vegetation along transects in the area of fastest mangrove progression showed an average progression rate of 53·12±5·86 m year -1, quite similar to the estimate (48·4 m year -1) derived from remote sensing techniques for the area where the transects were surveyed. Avicennia albawas found to dominate the vegetation at the progressing edge of the mangrove, followed by Sonneratia caseolaris, with Rhizophora apiculatabeing present only occasionally. The fast colonization of A. albaover the mud flat was supported by a large export flux of mangrove propagules from the channels draining the mangrove forest, which averaged 3715±920 and 1900±808 fruits day -1in each of the channels examined. Extrapolation of the long-term mean mangrove progression rate observed along the eastern bank of the Pak Phanang Bay suggested that this mangrove forest will increase by 33 ha year -1. These results provide evidence that natural mangrove colonization can be a rapid process if sufficient propagules of the pioneer species ( A. albaand S. caseolaris) are available, and point, therefore, to alternative

  5. Characterizing Forest Change Using Community-Based Monitoring Data and Landsat Time Series.

    PubMed

    DeVries, Ben; Pratihast, Arun Kumar; Verbesselt, Jan; Kooistra, Lammert; Herold, Martin

    2016-01-01

    Increasing awareness of the issue of deforestation and degradation in the tropics has resulted in efforts to monitor forest resources in tropical countries. Advances in satellite-based remote sensing and ground-based technologies have allowed for monitoring of forests with high spatial, temporal and thematic detail. Despite these advances, there is a need to engage communities in monitoring activities and include these stakeholders in national forest monitoring systems. In this study, we analyzed activity data (deforestation and forest degradation) collected by local forest experts over a 3-year period in an Afro-montane forest area in southwestern Ethiopia and corresponding Landsat Time Series (LTS). Local expert data included forest change attributes, geo-location and photo evidence recorded using mobile phones with integrated GPS and photo capabilities. We also assembled LTS using all available data from all spectral bands and a suite of additional indices and temporal metrics based on time series trajectory analysis. We predicted deforestation, degradation or stable forests using random forest models trained with data from local experts and LTS spectral-temporal metrics as model covariates. Resulting models predicted deforestation and degradation with an out of bag (OOB) error estimate of 29% overall, and 26% and 31% for the deforestation and degradation classes, respectively. By dividing the local expert data into training and operational phases corresponding to local monitoring activities, we found that forest change models improved as more local expert data were used. Finally, we produced maps of deforestation and degradation using the most important spectral bands. The results in this study represent some of the first to combine local expert based forest change data and dense LTS, demonstrating the complementary value of both continuous data streams. Our results underpin the utility of both datasets and provide a useful foundation for integrated forest

  6. Characterizing Forest Change Using Community-Based Monitoring Data and Landsat Time Series

    PubMed Central

    DeVries, Ben; Pratihast, Arun Kumar; Verbesselt, Jan; Kooistra, Lammert; Herold, Martin

    2016-01-01

    Increasing awareness of the issue of deforestation and degradation in the tropics has resulted in efforts to monitor forest resources in tropical countries. Advances in satellite-based remote sensing and ground-based technologies have allowed for monitoring of forests with high spatial, temporal and thematic detail. Despite these advances, there is a need to engage communities in monitoring activities and include these stakeholders in national forest monitoring systems. In this study, we analyzed activity data (deforestation and forest degradation) collected by local forest experts over a 3-year period in an Afro-montane forest area in southwestern Ethiopia and corresponding Landsat Time Series (LTS). Local expert data included forest change attributes, geo-location and photo evidence recorded using mobile phones with integrated GPS and photo capabilities. We also assembled LTS using all available data from all spectral bands and a suite of additional indices and temporal metrics based on time series trajectory analysis. We predicted deforestation, degradation or stable forests using random forest models trained with data from local experts and LTS spectral-temporal metrics as model covariates. Resulting models predicted deforestation and degradation with an out of bag (OOB) error estimate of 29% overall, and 26% and 31% for the deforestation and degradation classes, respectively. By dividing the local expert data into training and operational phases corresponding to local monitoring activities, we found that forest change models improved as more local expert data were used. Finally, we produced maps of deforestation and degradation using the most important spectral bands. The results in this study represent some of the first to combine local expert based forest change data and dense LTS, demonstrating the complementary value of both continuous data streams. Our results underpin the utility of both datasets and provide a useful foundation for integrated forest

  7. Characterizing Forest Change Using Community-Based Monitoring Data and Landsat Time Series.

    PubMed

    DeVries, Ben; Pratihast, Arun Kumar; Verbesselt, Jan; Kooistra, Lammert; Herold, Martin

    2016-01-01

    Increasing awareness of the issue of deforestation and degradation in the tropics has resulted in efforts to monitor forest resources in tropical countries. Advances in satellite-based remote sensing and ground-based technologies have allowed for monitoring of forests with high spatial, temporal and thematic detail. Despite these advances, there is a need to engage communities in monitoring activities and include these stakeholders in national forest monitoring systems. In this study, we analyzed activity data (deforestation and forest degradation) collected by local forest experts over a 3-year period in an Afro-montane forest area in southwestern Ethiopia and corresponding Landsat Time Series (LTS). Local expert data included forest change attributes, geo-location and photo evidence recorded using mobile phones with integrated GPS and photo capabilities. We also assembled LTS using all available data from all spectral bands and a suite of additional indices and temporal metrics based on time series trajectory analysis. We predicted deforestation, degradation or stable forests using random forest models trained with data from local experts and LTS spectral-temporal metrics as model covariates. Resulting models predicted deforestation and degradation with an out of bag (OOB) error estimate of 29% overall, and 26% and 31% for the deforestation and degradation classes, respectively. By dividing the local expert data into training and operational phases corresponding to local monitoring activities, we found that forest change models improved as more local expert data were used. Finally, we produced maps of deforestation and degradation using the most important spectral bands. The results in this study represent some of the first to combine local expert based forest change data and dense LTS, demonstrating the complementary value of both continuous data streams. Our results underpin the utility of both datasets and provide a useful foundation for integrated forest

  8. Using the ratio of optical channels in satellite image decoding in monitoring biodiversity of boreal forests

    NASA Astrophysics Data System (ADS)

    Rozhkov, Yurj P.; Kondakova, Maria Y.

    2013-10-01

    The study contains the results of forest monitoring at three levels: the forests condition assessment at the time of recording or mapping for this indicator, the seasonal changes assessment in the forests condition, mainly during the vegetation period and the evaluation of long-term changes in the values of the studied parameters on the example of the forests recovery after a fire. The use of two indices - NDVI and Image Difference in the boreal forests monitoring is treated. NDVI assesses the state of plant biomass and its productivity. The rate of Image Difference characterizes the optical density and allows estimate the density of the forest stand. In addition, by identifying Image Difference on summer and autumn pictures it can makes a distinction of different wood species, to divide forest areas, which consist of deciduous and coniferous species and larch which shedded needles at the end of the vegetation period. Therefore, it is possible to differentiate the pine, cedar, spruce forests on the one side and birch, larch, alder on the other side. The optical density of the forest decreases after the needles- and the leaf sheddings. Using the index Image Difference in estimates of long-term changes of the forest stand shows the trend of changes of the forest density and the tree species composition. The results of the analysis of the recovery process of the forest after a fire in the period from 1995 to 2009 showed how shoots of birch, larch and pine recover wastelands.

  9. Estimating Mangrove Canopy Height and Above-Ground Biomass in Everglades National Park with Airbone LiDAR and TanDEM-X Data.

    NASA Astrophysics Data System (ADS)

    Feliciano, E. A.; Wdowinski, S.; Potts, M. D.; Fatoyinbo, T. E.; Lee, S. K.

    2014-12-01

    The coastal mangroves forests of Everglades National Park (ENP) are well protected from development. Nevertheless, climate change, hurricanes and other anthropogenic disturbances have affected these intertidal ecosystems. Understanding and monitoring forest structural parameters such as canopy height and above-ground biomass (AGB) are important for the establishment of an historical database for past, present and future ecosystem comparison. Forest canopy height has a well understood and directly proportional correlation with AGB. It is possible to derive it using (1) airborne LiDAR/Laser Scanning (ALS) or (2) space-borne radar systems such as Shuttle Radar Topography Mission (SRTM) and TanDEM-X (TDX). A previous study of the mangrove canopy height and AGB in the ENP was conducted a decade ago based on ALS data acquired in 2004 in conjunction with SRTM data, which were acquired in 2000 (Simard et al. 2006). In this study we estimated canopy height and AGB using an ALS dataset acquired in 2012 and TDX data acquired during the years 2012-2014. The ALS dataset was acquired along a 16.5 x 1.5 km swath of mangrove forest with variable canopy height. The sampled areas were representative of mangrove stature and structure in the whole ENP. Analysis of the ALS dataset showed that mangrove canopy height can reach up to ~25 meters close to the coastal ENP waters. Additionally, by comparing our ALS results with those of a previous study by Simard et al. (2006) we identified areas where mangrove height changes greater than ± 3 meters occurred. To expand the study area to the full ENP mangrove ecosystem we processed single-polarization TDX data to obtain a Digital Canopy Model (DCM) that represents the mangrove canopy height. In order to obtain the true canopy height we calibrated the TDX phase center height with ALS true canopy height. Preliminary results of a corrected single-polarized (HH) TDX scene show that mangrove canopy height can reach up to ~25 meters in the western

  10. Monitoring environmental state of Alaskan forests with AIRSAR

    NASA Technical Reports Server (NTRS)

    Mcdonald, Kyle C.; Way, Jobea; Rignot, Eric; Williams, Cindy; Viereck, Les; Adams, Phylis

    1992-01-01

    During March 1988 and May 1991, the JPL airborne synthetic aperture radar, AIRSAR, collected sets of multi-temporal imagery of the Bonanza Creek Experimental Forest near Fairbanks, Alaska. These data sets consist of series of multi-polarized images collected at P-, L-, and C-bands each over a period of a few days. The AIRSAR campaigns were complemented with extensive ground measurements that included observations of both static canopy characteristics such as forest architecture as well as properties that vary on short term time scales such as canopy dielectric conditions. Observations exist for several stands of deciduous and coniferous species including white spruce (Picea glauca), black spruce (Picea mariana), and balsam poplar (Populus balsamifera). Although the duration of each campaign was fairly short, significant changes in environmental conditions caused notable variations in the physiological state of the canopies. During the 1988 campaign, environmental conditions ranged from unseasonably warm to more normal subfreezing temperatures. This permitted AIRSAR observations of frozen and thawed canopy states. During May 1991, ice jams that occurred along the river caused many stands to flood while the subsequent clearing of the river then allowed the waters to recede, leaving a snow covered ground surface. This allowed observations of several stands during both flooded and nonflooded conditions. Furthermore, the local weather varied from clear sunny days to heavy overcast days with some occurrence of rain. Measurements of leaf water potential indicated that this caused significant variations in canopy water status, allowing SAR observations of water stressed and unstressed trees. Mean backscatter from several stands is examined for the various canopy physiological states. The changes in canopy backscatter that occur as a function of environmental and physiological state are analyzed. Preliminary results of a backscatter signature modeling analysis are presented

  11. Forest Watch: Using Student Data to Monitor Forest Response to Ground-Level Ozone

    NASA Astrophysics Data System (ADS)

    Spencer, S.; Rock, B. N.

    2006-12-01

    Forest Watch, a k-12 science outreach program begun at the University of New Hampshire (UNH) in 1991, has engaged pre-college students in providing UNH researchers with data on the annual response of white pine (Pinus strobus; a bio-indicator species for ozone exposure) to ground-level ozone across the New England region. Each year, student-collected growth and foliar symptomology data for 5 pine trees adjacent to their schools, along with first-year foliar samples, are submitted to UNH. Key foliar symptoms and student data are compared with summer monthly (JJA) maximum ozone concentrations collected by state and federal ozone monitoring stations across the region. To date, tree health indicators are inversely correlated (r2=0.83;p=0.10) with ozone concentrations: low ozone levels correlate with symptoms of good health (spectral indices diagnostic of high foliar chlorophyll levels and moisture content, normal incremental growth, low number of foliar symptoms), while summers characterized by high ozone concentrations correlate with symptoms of reduced health (low chlorophyll indices and moisture content, reduced incremental growth, increased number of foliar symptoms). In drought years (1999, 2001, 2002, 2003) few foliar symptoms of ozone damage are seen even though ozone levels were high, likely due to drought-induced stomatal closure. Based on student data since 1998, either low ozone summers, or drought summers have resulted in improved health in the sampled trees (n=30). Based on the success of Forest Watch in New England, we are exploring the extension of the program to Colorado as Front Range Forest Watch, operated from Colorado State University (CSU). The primary objective is to develop a student-scientist-local agency project that addresses real ecological issues in northern Colorado, including ozone pollution, and to provide pre-college students and teachers authentic science experiences. CSU runs a GK-12 program with Poudre School District in northern

  12. [The mangrove and others vegetation associations in de Gandoca lagoon, Limón, Costa Rica].

    PubMed

    Coll, M; Fonseca, A C; Cortés, J

    2001-12-01

    Six plant associations were identified at Gandoca Lagoon by photointerpretation and field verification: a) mangroves, b) palm trees swamp, and palm trees with Acrostichum aureum and A. danaefolium, c) mixed palm trees, d) very humid tropical rain forest, and e) tropical beach vegetation. The mangroves cover 12.5 ha surrounding the lagoon and extend 2 km up the Gandoca River. Rhizophora mangle (red mangrove) was the dominant species, with Avicennia germinans (black mangrove), Laguncularia racemosa (white mangrove) and Conocarpus erectus (buttonwood) also present. Moving inland the mangroves grade into a tropical rain forest. Gandoca, the largest and best preserved mangrove of Caribbean Costa Rica, tripled its area from 1976 to 2000. Possible causes include sedimentation and the Limón earthquake, which may have subside the lagoon area. PMID:15264546

  13. Monitoring Strategies for REDD+: Integrating Field, Airborne, and Satellite Observations of Amazon Forests

    NASA Technical Reports Server (NTRS)

    Morton, Douglas; Souza, Carlos, Jr.; Souza, Carlos, Jr.; Keller, Michael

    2012-01-01

    Large-scale tropical forest monitoring efforts in support of REDD+ (Reducing Emissions from Deforestation and forest Degradation plus enhancing forest carbon stocks) confront a range of challenges. REDD+ activities typically have short reporting time scales, diverse data needs, and low tolerance for uncertainties. Meeting these challenges will require innovative use of remote sensing data, including integrating data at different spatial and temporal resolutions. The global scientific community is engaged in developing, evaluating, and applying new methods for regional to global scale forest monitoring. Pilot REDD+ activities are underway across the tropics with support from a range of national and international groups, including SilvaCarbon, an interagency effort to coordinate US expertise on forest monitoring and resource management. Early actions on REDD+ have exposed some of the inherent tradeoffs that arise from the use of incomplete or inaccurate data to quantify forest area changes and related carbon emissions. Here, we summarize recent advances in forest monitoring to identify and target the main sources of uncertainty in estimates of forest area changes, aboveground carbon stocks, and Amazon forest carbon emissions.

  14. Framework for video-based monitoring of forest insect defoliation and discoloration

    NASA Astrophysics Data System (ADS)

    Zhao, Feifei; Wang, Yafei; Qiao, Yanyou

    2015-01-01

    Pest damage is a general problem that disturbs the growth of forests, influencing carbon sequestration and causing economic losses. In the past decades, many studies have been conducted to monitor and detect forest insect damage using satellite remote sensing technology. Satellite remote sensing has a satellite or aerial vision allowing the monitoring of extensive forest areas, but it usually requires constant time periods and is prone to cloud interference. To enable more efficient and effective monitoring of forest pest damage, a video-based monitoring framework is presented. This framework comprises three key parts: (1) video positioning of forest insect damage based on digital elevation model (DEM) and the parameters obtained from the pan-tilt-zoom camera, (2) integration of two-dimensional/three-dimensional geographic information system and video surveillance to provide more intuitionistic monitoring and assistance for positioning, (3) on-site verification conducted by ground surveys and guided through global positioning system (GPS) integrated in the embedded devices. The experiment was carried out over two forest areas to validate the proposed method. Results showed that the framework bears a sound positioning accuracy and high detection ratio, which could be effectively used in detecting and monitoring forest insect defoliation and discoloration.

  15. Economics: Mangroves' hidden value

    NASA Astrophysics Data System (ADS)

    Murray, Brian C.

    2012-11-01

    Mangroves are being lost at an alarming rate as their conversion for aquaculture and other uses is profitable. Research, however, suggests that valuing the deep reserves of carbon in mangrove sediments may be the key to their survival.

  16. Interagency Collaborators Develop and Implement ForWarn, a National, Near Real Time Forest Monitoring Tool

    NASA Technical Reports Server (NTRS)

    Underwood, Lauren

    2013-01-01

    ForWarn is a satellite-based forest monitoring tool that is being used to detect and monitor disturbances to forest conditions and forest health. It has been developed through the synergistic efforts, capabilities and contributions of four federal agencies, including the US Forest Service Eastern Forest and Western Wildland Environmental Threat Assessment Centers, NASA Stennis Space Center (SSC), Department of Energy's (DOE) Oak Ridge National Laboratory (ORNL) and US Geological Survey Earth (USGS) Earth Research Observation System (EROS), as well as university partners, including the University of North Carolina Asheville's National Environmental Modeling and Analysis Center (NEMAC). This multi-organizational partnership is key in producing a unique, path finding near real-time forest monitoring system that is now used by many federal, state and local government end-users. Such a system could not have been produced so effectively by any of these groups on their own. The forests of the United States provide many societal values and benefits, ranging from ecological, economic, cultural, to recreational. Therefore, providing a reliable and dependable forest and other wildland monitoring system is important to ensure the continued health, productivity, sustainability and prudent use of our Nation's forests and forest resources. ForWarn does this by producing current health indicator maps of our nation's forests based on satellite data from NASA's MODIS (Moderate Resolution Imaging Spectroradiometer) sensors. Such a capability can provide noteworthy value, cost savings and significant impact at state and local government levels because at those levels of government, once disturbances are evident and cause negative impacts, a response must be carried out. The observations that a monitoring system like ForWarn provide, can also contribute to a much broader-scale understanding of vegetation disturbances.

  17. Dynamics of suspended sediment exchange and transport in a degraded mangrove creek in Kenya.

    PubMed

    Kitheka, Johnson U; Ongwenyi, George S; Mavuti, Kenneth M

    2002-12-01

    This study focuses on sediment exchange dynamics in Mwache Creek, a shallow tidal mangrove wetland in Kenya. The surface area of the creek is 17 km2 at high water spring. The creek experiences semidiurnal tides with tidal ranges of 3.2 m and 1.4 m during spring and neap tides, respectively. The creek is ebb dominant in the frontwater zone main channel and is flood dominant in the backwater zone main channel. During rainy season, the creek receives freshwater and terrigenous sediments from the seasonal Mwache River. Heavy supply of terrigenous sediments during the El Niño of 1997-1998 led to the huge deposition of sediments (10(60 tonnes) in the wetland that caused massive destruction of the mangrove forest in the upper region. In this study, sea level, tidal discharges, tidal current velocities, salinity, total suspended sediment concentrations (TSSC) and particulate organic sediment concentrations (POSC) measured in stations established within the main channel and also within the mangrove forests, were used to determine the dynamics of sediment exchange between the frontwater and backwater zones of the main channel including also the exchange with mangrove forests. The results showed that during wet seasons, the high suspended sediment concentration associated with river discharge and tidal resuspension of fine channel-bed sediment accounts for the inflow of highly turbid water into the degraded mangrove forest. Despite the degradation of the mangrove forest, sediment outflow from the mangrove forest was considerably less than the inflow. This caused a net trapping of sediment in the wetland. The net import of the sediment dominated in spring tide during both wet and dry season and during neap tide in the wet season. However, as compared to heavily vegetated mangrove wetlands, the generally degraded Mwache Creek mangrove wetland sediment trapping efficiency is low as the average is about 30% for the highly degraded backwater zone mangrove forest and 65% in the

  18. Linking physiological processes with mangrove forest structure: phosphorus deficiency limits canopy development, hydraulic conductivity and photosynthetic carbon gain in dwarf Rhizophora mangle.

    PubMed

    Lovelock, Catherine E; Ball, Marilyn C; Choat, Brendan; Engelbrecht, Bettina M J; Holbrook, N Michelle; Feller, Ilka C

    2006-05-01

    Spatial gradients in mangrove tree height in barrier islands of Belize are associated with nutrient deficiency and sustained flooding in the absence of a salinity gradient. While nutrient deficiency is likely to affect many parameters, here we show that addition of phosphorus (P) to dwarf mangroves stimulated increases in diameters of xylem vessels, area of conductive xylem tissue and leaf area index (LAI) of the canopy. These changes in structure were consistent with related changes in function, as addition of P also increased hydraulic conductivity (Ks), stomatal conductance and photosynthetic assimilation rates to the same levels measured in taller trees fringing the seaward margin of the mangrove. Increased xylem vessel size and corresponding enhancements in stem hydraulic conductivity in P fertilized dwarf trees came at the cost of enhanced mid-day loss of hydraulic conductivity and was associated with decreased assimilation rates in the afternoon. Analysis of trait plasticity identifies hydraulic properties of trees as more plastic than those of leaf structural and physiological characteristics, implying that hydraulic properties are key in controlling growth in mangroves. Alleviation of P deficiency, which released trees from hydraulic limitations, reduced the structural and functional distinctions between dwarf and taller fringing tree forms of Rhizophora mangle.

  19. Linking physiological processes with mangrove forest structure: phosphorus deficiency limits canopy development, hydraulic conductivity and photosynthetic carbon gain in dwarf Rhizophora mangle.

    PubMed

    Lovelock, Catherine E; Ball, Marilyn C; Choat, Brendan; Engelbrecht, Bettina M J; Holbrook, N Michelle; Feller, Ilka C

    2006-05-01

    Spatial gradients in mangrove tree height in barrier islands of Belize are associated with nutrient deficiency and sustained flooding in the absence of a salinity gradient. While nutrient deficiency is likely to affect many parameters, here we show that addition of phosphorus (P) to dwarf mangroves stimulated increases in diameters of xylem vessels, area of conductive xylem tissue and leaf area index (LAI) of the canopy. These changes in structure were consistent with related changes in function, as addition of P also increased hydraulic conductivity (Ks), stomatal conductance and photosynthetic assimilation rates to the same levels measured in taller trees fringing the seaward margin of the mangrove. Increased xylem vessel size and corresponding enhancements in stem hydraulic conductivity in P fertilized dwarf trees came at the cost of enhanced mid-day loss of hydraulic conductivity and was associated with decreased assimilation rates in the afternoon. Analysis of trait plasticity identifies hydraulic properties of trees as more plastic than those of leaf structural and physiological characteristics, implying that hydraulic properties are key in controlling growth in mangroves. Alleviation of P deficiency, which released trees from hydraulic limitations, reduced the structural and functional distinctions between dwarf and taller fringing tree forms of Rhizophora mangle. PMID:17087463

  20. [The Purruja mangrove, Golfito, Costa Rica: a management model].

    PubMed

    Silva, Ana Margarita; Carrillo, Norma Natalia

    2004-12-01

    The Purruja mangrove (Golfito, Costa Rica) has an estimated area of 70 ha. A socio-biological research was the ground to set initial goals to manage the resources and to identify the mangrove biological condition. Community participation and the local organization were key factors in developing an integrated model for the management of natural resources. Constant monitoring and institutional networks were the other two factors to manage the mangrove. The constant profesional support was a tool to facilitate the acomplishment of goals and to establish an institucional network to promote local group iniciatives for collaborative management of the Purruja mangrove.

  1. A socio-ecological assessment aiming at improved forest resource management and sustainable ecotourism development in the mangroves of Tanbi Wetland National Park, The Gambia, West Africa.

    PubMed

    Satyanarayana, Behara; Bhanderi, Preetika; Debry, Mélanie; Maniatis, Danae; Foré, Franka; Badgie, Dawda; Jammeh, Kawsu; Vanwing, Tom; Farcy, Christine; Koedam, Nico; Dahdouh-Guebas, Farid

    2012-07-01

    Although mangroves dominated by Avicennia germinans and Rhizophora mangle are extending over 6000 ha in the Tanbi Wetland National Park (TWNP) (The Gambia), their importance for local populations (both peri-urban and urban) is not well documented. For the first time, this study evaluates the different mangrove resources in and around Banjul (i.e., timber, non-timber, edible, and ethnomedicinal products) and their utilization patterns, including the possibility of ecotourism development. The questionnaire-based results have indicated that more than 80% of peri-urban population rely on mangroves for timber and non-timber products and consider them as very important for their livelihoods. However, at the same time, urban households demonstrate limited knowledge on mangrove species and their ecological/economic benefits. Among others, fishing (including the oyster-Crassostrea cf. gasar collection) and tourism are the major income-generating activities found in the TWNP. The age-old practices of agriculture in some parts of the TWNP are due to scarcity of land available for agriculture, increased family size, and alternative sources of income. The recent focus on ecotourism (i.e., boardwalk construction inside the mangroves near Banjul city) received a positive response from the local stakeholders (i.e., users, government, and non-government organizations), with their appropriate roles in sharing the revenue, rights, and responsibilities of this project. Though the guidelines for conservation and management of the TWNP seem to be compatible, the harmony between local people and sustainable resource utilization should be ascertained. PMID:22351596

  2. A socio-ecological assessment aiming at improved forest resource management and sustainable ecotourism development in the mangroves of Tanbi Wetland National Park, The Gambia, West Africa.

    PubMed

    Satyanarayana, Behara; Bhanderi, Preetika; Debry, Mélanie; Maniatis, Danae; Foré, Franka; Badgie, Dawda; Jammeh, Kawsu; Vanwing, Tom; Farcy, Christine; Koedam, Nico; Dahdouh-Guebas, Farid

    2012-07-01

    Although mangroves dominated by Avicennia germinans and Rhizophora mangle are extending over 6000 ha in the Tanbi Wetland National Park (TWNP) (The Gambia), their importance for local populations (both peri-urban and urban) is not well documented. For the first time, this study evaluates the different mangrove resources in and around Banjul (i.e., timber, non-timber, edible, and ethnomedicinal products) and their utilization patterns, including the possibility of ecotourism development. The questionnaire-based results have indicated that more than 80% of peri-urban population rely on mangroves for timber and non-timber products and consider them as very important for their livelihoods. However, at the same time, urban households demonstrate limited knowledge on mangrove species and their ecological/economic benefits. Among others, fishing (including the oyster-Crassostrea cf. gasar collection) and tourism are the major income-generating activities found in the TWNP. The age-old practices of agriculture in some parts of the TWNP are due to scarcity of land available for agriculture, increased family size, and alternative sources of income. The recent focus on ecotourism (i.e., boardwalk construction inside the mangroves near Banjul city) received a positive response from the local stakeholders (i.e., users, government, and non-government organizations), with their appropriate roles in sharing the revenue, rights, and responsibilities of this project. Though the guidelines for conservation and management of the TWNP seem to be compatible, the harmony between local people and sustainable resource utilization should be ascertained.

  3. Monitoring forest land from high altitude and from space

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Forest inventory, forest stress, and standardization and calibration studies are presented. These include microscale photointerpretation of forest and nonforest land classes, multiseasonal film densities for automated forest and nonforest land classification, trend and spread of bark beetle infestations from 1968 through 1971, aerial photography for determining optimum levels of stand density to reduce such infestations, use of airborne spectrometers and multispectral scanners for previsual detection of Ponderosa pine trees under stress from insects and diseases, establishment of an earth resources technology satellite test site in the Black Hills and the identification of natural resolution targets, detection of root disease impact on forest stands by sequential orbital and suborbital multispectral photography, and calibration of color aerial photography.

  4. Monitoring forest land from high altitude and from space

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The significant findings are reported for remote sensing of forest lands conducted during the period October 1, 1965 to December 31, 1972. Forest inventory research included the use of aircraft and space imagery for forest and nonforest land classification, and land use classification by automated procedures, multispectral scanning, and computerized mapping. Forest stress studies involved previsual detection of ponderosa pine under stress from insects and disease, bark bettle infestations in the Black Hills, and root disease impacts on forest stands. Standardization and calibration studies were made to develop a field test of an ERTS-matched four-channel spectrometer. Calibration of focal plane shutters and mathematical modeling of film characteristic curves were also studied. Documents published as a result of all forestry studies funded by NASA for the Earth Resources Survey Program from 1965 through 1972 are listed.

  5. Options for monitoring and estimating historical carbon emissions from forest degradation in the context of REDD+

    PubMed Central

    2011-01-01

    Measuring forest degradation and related forest carbon stock changes is more challenging than measuring deforestation since degradation implies changes in the structure of the forest and does not entail a change in land use, making it less easily detectable through remote sensing. Although we anticipate the use of the IPCC guidance under the United Framework Convention on Climate Change (UNFCCC), there is no one single method for monitoring forest degradation for the case of REDD+ policy. In this review paper we highlight that the choice depends upon a number of factors including the type of degradation, available historical data, capacities and resources, and the potentials and limitations of various measurement and monitoring approaches. Current degradation rates can be measured through field data (i.e. multi-date national forest inventories and permanent sample plot data, commercial forestry data sets, proxy data from domestic markets) and/or remote sensing data (i.e. direct mapping of canopy and forest structural changes or indirect mapping through modelling approaches), with the combination of techniques providing the best options. Developing countries frequently lack consistent historical field data for assessing past forest degradation, and so must rely more on remote sensing approaches mixed with current field assessments of carbon stock changes. Historical degradation estimates will have larger uncertainties as it will be difficult to determine their accuracy. However improving monitoring capacities for systematic forest degradation estimates today will help reduce uncertainties even for historical estimates. PMID:22115360

  6. Disentangling the effects of climate, species, and management on growth and mortality of southeast Asian mangroves

    NASA Astrophysics Data System (ADS)

    Baker, Patrick; Bunyavejchewin, Sarayudh; Robinson, Andrew

    2013-04-01

    Mangrove forests are one of the most biologically important ecosystems of the littoral tropics. They provide a wide range of ecosystem services including tsunami protection, food production, and waste processing. They are also rapidly disappearing due to increasing rates of clearance for development and aquaculture. It remains unclear how mangroves will respond to changing climatic conditions. Here we discuss the results of a long-term study that explored the interacting effects of climate, species, and management practices on annual variability of growth and mortality of mangroves in peninsular Thailand. The 15-year study period included the extreme 1997-98 ENSO event that led to widespread drought-induced mortality and forest fires across the region, but which appeared to have little impact on the mangroves. Our results provide an important, and much-needed, framework for conservation and forest management planning in these mangrove forests given future concerns and uncertainty about climate change in the tropics.

  7. Monitoring forest cover loss using multiple data streams, a case study of a tropical dry forest in Bolivia

    NASA Astrophysics Data System (ADS)

    Dutrieux, Loïc Paul; Verbesselt, Jan; Kooistra, Lammert; Herold, Martin

    2015-09-01

    Automatically detecting forest disturbances as they occur can be extremely challenging for certain types of environments, particularly those presenting strong natural variations. Here, we use a generic structural break detection framework (BFAST) to improve the monitoring of forest cover loss by combining multiple data streams. Forest change monitoring is performed using Landsat data in combination with MODIS or rainfall data to further improve the modelling and monitoring. We tested the use of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) with varying spatial aggregation window sizes as well as a rainfall derived index as external regressors. The method was evaluated on a dry tropical forest area in lowland Bolivia where forest cover loss is known to occur, and we validated the results against a set of ground truth samples manually interpreted using the TimeSync environment. We found that the addition of an external regressor allows to take advantage of the difference in spatial extent between human induced and naturally induced variations and only detect the processes of interest. Of all configurations, we found the 13 by 13 km MODIS NDVI window to be the most successful, with an overall accuracy of 87%. Compared with a single pixel approach, the proposed method produced better time-series model fits resulting in increases of overall accuracy (from 82% to 87%), and decrease in omission and commission errors (from 33% to 24% and from 3% to 0% respectively). The presented approach seems particularly relevant for areas with high inter-annual natural variability, such as forests regularly experiencing exceptional drought events.

  8. National Scale Monitoring Reporting and Verification of Deforestation and Forest Degradation in Guyana

    NASA Astrophysics Data System (ADS)

    Bholanath, P.; Cort, K.

    2015-04-01

    Monitoring deforestation and forest degradation at national scale has been identified as a national priority under Guyana's REDD+ Programme. Based on Guyana's MRV (Monitoring Reporting and Verification) System Roadmap developed in 2009, Guyana sought to establish a comprehensive, national system to monitor, report and verify forest carbon emissions resulting from deforestation and forest degradation in Guyana. To date, four national annual assessments have been conducted: 2010, 2011, 2012 and 2013. Monitoring of forest change in 2010 was completed with medium resolution imagery, mainly Landsat 5. In 2011, assessment was conducted using a combination of Landsat (5 and 7) and for the first time, 5m high resolution imagery, with RapidEye coverage for approximately half of Guyana where majority of land use changes were taking place. Forest change in 2013 was determined using high resolution imagery for the whole of Guyana. The current method is an automated-assisted process of careful systematic manual interpretation of satellite imagery to identify deforestation based on different drivers of change. The minimum mapping unit (MMU) for deforestation is 1 ha (Guyana's forest definition) and a country-specific definition of 0.25 ha for degradation. The total forested area of Guyana is estimated as 18.39 million hectares (ha). In 2012 as planned, Guyana's forest area was reevaluated using RapidEye 5 m imagery. Deforestation in 2013 is estimated at 12 733 ha which equates to a total deforestation rate of 0.068%. Significant progress was made in 2012 and 2013, in mapping forest degradation. The area of forest degradation as measured by interpretation of 5 m RapidEye satellite imagery in 2013 was 4 352 ha. All results are subject to accuracy assessment and independent third party verification.

  9. The Role of Satellite Data for the National Forest Monitoring Systems in the Context of REDD+

    NASA Astrophysics Data System (ADS)

    Jonckheere, Inge

    2012-04-01

    Reducing Emissions from Deforestation and Forest Degradation (REDD) is an effort to create a financial value for the carbon stored in forests, offering incentives for developing countries to reduce emissions from forested lands and invest in low-carbon paths to sustainable development. “REDD+” goes beyond deforestation and forest degradation, and includes the role of conservation, sustainable management of forests and enhancement of forest carbon stocks. In the framework of getting countries ready for REDD+, the UN-REDD Programme assists developing countries to prepare and implement national REDD+ strategies. For the monitoring, reporting and verification (MRV), FAO supports the countries to develop national forest monitoring systems (NFMS) based on satellite data that allow for credible MRV of REDD+ activities through time. The UN-REDD Programme through a joint effort of FAO and Brazil's National Space Agency, INPE, is supporting countries to develop cost- effective, robust and compatible national monitoring and MRV systems, providing tools, methodologies, training and knowledge sharing that help countries to strengthen their technical and institutional capacity for effective MRV systems. The Brazilian forest monitoring system, TerraAmazon, which is used as a multi-user basis, allows countries to adapt it to country needs. With the technical assistance of FAO, INPE and other stakeholders, the countries will set up an autonomous operational satellite forest monitoring systems. A beta version and the methodologies of the system for DRC and PNG are launched in Durban (SA) during COP 17, while Paraguay, Zambia and Viet Nam are in development in 2012.

  10. Multi-Sensor Monitoring And Assessment Of Forest Resources: Supporting A Forest Observation System For Seiberia

    NASA Astrophysics Data System (ADS)

    Huttich, Christian; Eberle, Jonas; Schmullius, Christiane; Bartalev, Sergey; Emelyanov, Kirill; Korets, Mikhail; Shvidenko, Anatoly; Schepaschenko, Dmitry

    2013-12-01

    Above ground biomass - one of the considered Essential Biodiversity and Climate Variables (ECV, EBV) - is an important structural parameter describing the state and dynamics of the Boreal zone. More than 50 % of the Russian forest inventory has been updated more than 25 years ago. The consequence is that most of the existing forest inventory is obsolete. Moreover, human and environmental forest disturbances continuously affect changing forest cover and biomass levels. The magnitude and extent of ongoing environmental pressures (e.g. forest fragmentation and the impact of global climate change) and the loss rates of particular habitat types is not known so far. The ZAPÁS project and the Siberian Earth System Science Cluster (SIB- ESS-C) are aiming to provide standardized and validated forest resource geo-information products. In- situ and multi-agency satellite data are analysed in the framework of the EU-Russia Space Dialogue. At local scales biomass and forest cover change maps are generated and validated with up-to-date forest inventory data. At regional scales a synergy map of land cover and biomass information is developed to be used to improve a full terrestrial carbon accounting for Central Siberia.

  11. Hydrological Classification, a Practical Tool for Mangrove Restoration

    PubMed Central

    Van Loon, Anne F.; Te Brake, Bram; Van Huijgevoort, Marjolein H. J.; Dijksma, Roel

    2016-01-01

    Mangrove restoration projects, aimed at restoring important values of mangrove forests after degradation, often fail because hydrological conditions are disregarded. We present a simple, but robust methodology to determine hydrological suitability for mangrove species, which can guide restoration practice. In 15 natural and 8 disturbed sites (i.e. disused shrimp ponds) in three case study regions in south-east Asia, water levels were measured and vegetation species composition was determined. Using an existing hydrological classification for mangroves, sites were classified into hydrological classes, based on duration of inundation, and vegetation classes, based on occurrence of mangrove species. For the natural sites hydrological and vegetation classes were similar, showing clear distribution of mangrove species from wet to dry sites. Application of the classification to disturbed sites showed that in some locations hydrological conditions had been restored enough for mangrove vegetation to establish, in some locations hydrological conditions were suitable for various mangrove species but vegetation had not established naturally, and in some locations hydrological conditions were too wet for any mangrove species (natural or planted) to grow. We quantified the effect that removal of obstructions such as dams would have on the hydrology and found that failure of planting at one site could have been prevented. The hydrological classification needs relatively little data, i.e. water levels for a period of only one lunar tidal cycle without additional measurements, and uncertainties in the measurements and analysis are relatively small. For the study locations, the application of the hydrological classification gave important information about how to restore the hydrology to suitable conditions to improve natural regeneration or to plant mangrove species, which could not have been obtained by estimating elevation only. Based on this research a number of recommendations

  12. Hydrological Classification, a Practical Tool for Mangrove Restoration.

    PubMed

    Van Loon, Anne F; Te Brake, Bram; Van Huijgevoort, Marjolein H J; Dijksma, Roel

    2016-01-01

    Mangrove restoration projects, aimed at restoring important values of mangrove forests after degradation, often fail because hydrological conditions are disregarded. We present a simple, but robust methodology to determine hydrological suitability for mangrove species, which can guide restoration practice. In 15 natural and 8 disturbed sites (i.e. disused shrimp ponds) in three case study regions in south-east Asia, water levels were measured and vegetation species composition was determined. Using an existing hydrological classification for mangroves, sites were classified into hydrological classes, based on duration of inundation, and vegetation classes, based on occurrence of mangrove species. For the natural sites hydrological and vegetation classes were similar, showing clear distribution of mangrove species from wet to dry sites. Application of the classification to disturbed sites showed that in some locations hydrological conditions had been restored enough for mangrove vegetation to establish, in some locations hydrological conditions were suitable for various mangrove species but vegetation had not established naturally, and in some locations hydrological conditions were too wet for any mangrove species (natural or planted) to grow. We quantified the effect that removal of obstructions such as dams would have on the hydrology and found that failure of planting at one site could have been prevented. The hydrological classification needs relatively little data, i.e. water levels for a period of only one lunar tidal cycle without additional measurements, and uncertainties in the measurements and analysis are relatively small. For the study locations, the application of the hydrological classification gave important information about how to restore the hydrology to suitable conditions to improve natural regeneration or to plant mangrove species, which could not have been obtained by estimating elevation only. Based on this research a number of recommendations

  13. Hydrological Classification, a Practical Tool for Mangrove Restoration.

    PubMed

    Van Loon, Anne F; Te Brake, Bram; Van Huijgevoort, Marjolein H J; Dijksma, Roel

    2016-01-01

    Mangrove restoration projects, aimed at restoring important values of mangrove forests after degradation, often fail because hydrological conditions are disregarded. We present a simple, but robust methodology to determine hydrological suitability for mangrove species, which can guide restoration practice. In 15 natural and 8 disturbed sites (i.e. disused shrimp ponds) in three case study regions in south-east Asia, water levels were measured and vegetation species composition was determined. Using an existing hydrological classification for mangroves, sites were classified into hydrological classes, based on duration of inundation, and vegetation classes, based on occurrence of mangrove species. For the natural sites hydrological and vegetation classes were similar, showing clear distribution of mangrove species from wet to dry sites. Application of the classification to disturbed sites showed that in some locations hydrological conditions had been restored enough for mangrove vegetation to establish, in some locations hydrological conditions were suitable for various mangrove species but vegetation had not established naturally, and in some locations hydrological conditions were too wet for any mangrove species (natural or planted) to grow. We quantified the effect that removal of obstructions such as dams would have on the hydrology and found that failure of planting at one site could have been prevented. The hydrological classification needs relatively little data, i.e. water levels for a period of only one lunar tidal cycle without additional measurements, and uncertainties in the measurements and analysis are relatively small. For the study locations, the application of the hydrological classification gave important information about how to restore the hydrology to suitable conditions to improve natural regeneration or to plant mangrove species, which could not have been obtained by estimating elevation only. Based on this research a number of recommendations

  14. Polarimetric SAR Interferometry Evaluation in Mangroves

    NASA Technical Reports Server (NTRS)

    Lee, Seung-Kuk; Fatoyinbo,Temilola; Osmanoglu, Batuhan; Sun, Guoqing

    2014-01-01

    TanDEM-X (TDX) enables to generate an interferometric coherence without temporal decorrelation effect that is the most critical factor for a successful Pol-InSAR inversion, as have recently been used for forest parameter retrieval. This paper presents mangrove forest height estimation only using single-pass/single-baseline/dual-polarization TDX data by means of new dual-Pol-InSAR inversion technique. To overcome a lack of one polarization in a conventional Pol- InSAR inversion (i.e. an underdetermined problem), the ground phase in the Pol-InSAR model is directly estimated from TDX interferograms assuming flat underlying topography in mangrove forest. The inversion result is validated against lidar measurement data (NASA's G-LiHT data).

  15. Nutrient Enrichment Increases Mortality of Mangroves

    PubMed Central

    Lovelock, Catherine E.; Ball, Marilyn C.; Martin, Katherine C.; C. Feller, Ilka

    2009-01-01

    Nutrient enrichment of the coastal zone places intense pressure on marine communities. Previous studies have shown that growth of intertidal mangrove forests is accelerated with enhanced nutrient availability. However, nutrient enrichment favours growth of shoots relative to roots, thus enhancing growth rates but increasing vulnerability to environmental stresses that adversely affect plant water relations. Two such stresses are high salinity and low humidity, both of which require greater investment in roots to meet the demands for water by the shoots. Here we present data from a global network of sites that documents enhanced mortality of mangroves with experimental nutrient enrichment at sites where high sediment salinity was coincident with low rainfall and low humidity. Thus the benefits of increased mangrove growth in response to coastal eutrophication is offset by the costs of decreased resilience due to mortality during drought, with mortality increasing with soil water salinity along climatic gradients. PMID:19440554

  16. Microbial diversity in Brazilian mangrove sediments – a mini review

    PubMed Central

    Ghizelini, Angela Michelato; Mendonça-Hagler, Leda Cristina Santana; Macrae, Andrew

    2012-01-01

    The importance and protection of mangrove ecosystems has been recognized in Brazilian Federal law since 1965. Being protected in law, however, has not always guaranteed their protection in practice. Mangroves are found in coastal and estuarine locations, which are prime real estate for the growth of cities, ports and other economic activities important for Brazilian development. In this mini-review we introduce what mangroves are and why they are so important. We give a brief overview of the microbial diversity found in mangrove sediments and then focus on diversity studies from Brazilian mangroves. We highlight the breadth and depth of knowledge about mangrove microbial communities gained from studying Brazilian mangroves. We report on the exciting findings of molecular microbial ecology methods that have been very successfully applied to study bacterial communities. We note that there have been fewer studies that focus on fungal communities and that fungal diversity studies deserve more attention. The review ends with a look at how a combination of new molecular biology methods and isolation studies are being developed to monitor and conserve mangrove ecosystems and their associated microbial communities. These recent studies are having a global impact and we hope they will help to protect and re-establish mangrove ecosystems. PMID:24031949

  17. Global climate change mitigation and sustainable forest management--The challenge of monitoring and verification

    SciTech Connect

    Makundi, Willy R.

    1997-12-31

    In this paper, sustainable forest management is discussed within the historical and theoretical framework of the sustainable development debate. The various criteria and indicators for sustainable forest management put forth by different institutions are critically explored. Specific types of climate change mitigation policies/projects in the forest sector are identified and examined in the light of the general criteria for sustainable forest management. Areas of compatibility and contradiction between the climate mitigation objectives and the minimum criteria for sustainable forest management are identified and discussed. Emphasis is put on the problems of monitoring and verifying carbon benefits associated with such projects given their impacts on pre-existing policy objectives on sustainable forest management. The implications of such policy interactions on assignment of carbon credits from forest projects under Joint Implementation/Activities Implemented Jointly initiatives are discussed. The paper concludes that a comprehensive monitoring and verification regime must include an impact assessment on the criteria covered under other agreements such as the Biodiversity and/or Desertification Conventions. The actual carbon credit assigned to a specific project should at least take into account the negative impacts on the criteria for sustainable forest management. The value of the impacts and/or the procedure to evaluate them need to be established by interested parties such as the Councils of the respective Conventions.

  18. Nitrogen accumulation in forests. Exposure monitoring by mosses.

    PubMed

    Pesch, Roland; Schröder, Winfried; Schmidt, Gunther

    2007-03-21

    At present, there is still little information on nitrogen (N) accumulation in forests contrasting with the crucial importance of N in forest ecosystems. This work analyzes the N bioaccumulation in mosses from forested areas from Lower Saxony and North Rhine-Westphalia (two of 16 federal states of Germany), the Weser Ems Region (part of Lower Saxony), and the Euro Region Nissa (covering the Czech Republic, Germany, Poland). The studies involved samples collected from 190 sites between 1998 and 2005. Different spatial scales and regional differences in land use were chosen to assess the factors affecting N bioaccumulation in forested areas. A continuous reduction of N bioaccumulation was found from Lower Saxony (a region where agriculture is most predominant) to North Rhine-Westphalia (mostly urban). The Weser Ems Region (an agricultural region) showed a higher N concentration in mosses than the Euroregion Nissa (a former industrial region). Statistical analyses performed at the different spatial scales revealed that the areas showing greater agricultural and livestock spatial densities favor N bioaccumulation in mosses. N concentration in mosses was moderately correlated with the N concentration in the leaves and needles of the surrounding trees. No significant relationships were found regarding the crown density of forest trees or N deposition estimations from a combination of atmospheric models and deposition measurements.

  19. Cumulative impacts of hurricanes on Florida mangrove ecosystems: Sediment deposition, storm surges and vegetation

    USGS Publications Warehouse

    Smith, T. J.; Anderson, G.H.; Balentine, K.; Tiling, G.; Ward, G.A.; Whelan, K.R.T.

    2009-01-01

    Hurricanes have shaped the structure of mangrove forests in the Everglades via wind damage, storm surges and sediment deposition. Immediate effects include changes to stem size-frequency distributions and to species relative abundance and density. Long-term impacts to mangroves are poorly understood at present. We examine impacts of Hurricane Wilma on mangroves and compare the results to findings from three previous storms (Labor Day, Donna, Andrew). Surges during Wilma destroyed ??? 1,250 ha of mangroves and set back recovery that started following Andrew. Data from permanent plots affected by Andrew and Wilma showed no differences among species or between hurricanes for stem mortality or basal area lost. Hurricane damage was related to hydro-geomorphic type of forest. Basin mangroves suffered significantly more damage than riverine or island mangroves. The hurricane by forest type interaction was highly significant. Andrew did slightly more damage to island mangroves. Wilma did significantly more damage to basin forests. This is most likely a result of the larger and more spatially extensive storm surge produced by Wilma. Forest damage was not related to amount of sediment deposited. Analyses of reports from Donna and the Labor Day storm indicate that some sites have recovered following catastrophic disturbance. Other sites have been permanently converted into a different ecosystem, namely intertidal mudflats. Our results indicate that mangroves are not in a steady state as has been recently claimed. ?? 2009 The Society of Wetland Scientists.

  20. Food web structure in exotic and native mangroves: a Hawaii-Puerto Rico comparison.

    PubMed

    Demopoulos, Amanda W J; Fry, Brian; Smith, Craig R

    2007-09-01

    Plant invasions can fundamentally alter detrital inputs and the structure of detritus-based food webs. We examined the detrital pathways in mangrove food webs in native (Puerto Rican) and introduced (Hawaiian) Rhizophora mangle forests using a dual isotope approach and a mixing model. Based on trophic-level fractionation of 0-1 per thousand for delta(13)C and 2-3 per thousand for delta(15)N, among the invertebrates, only nematodes, oligochaetes, and nereid polychaetes from native mangroves exhibited stable isotopes consistent with a mangrove-derived diet. Certain fauna, in particular tubificid oligochaetes, had delta(13)C values consistent with the consumption of mangrove leaves, but they were depleted in (15)N, suggesting their primary nitrogen source was low in (15)N, and was possibly N(2)-fixing bacteria. In introduced mangroves, all feeding groups appeared to rely heavily on non-mangrove sources, especially phytoplankton inputs. Mixing model results and discriminant analysis showed clear separation of introduced and native mangrove sites based on differential food source utilization within feeding groups, with stronger and more diverse use of benthic foods observed in native forests. Observed differences between native and invasive mangrove food webs may be due to Hawaiian detritivores being poorly adapted to utilizing the tannin-rich, nitrogen-poor mangrove detritus. In addition, differential utilization of mangrove detritus between native and introduced mangroves may be a consequence of forest age. We postulate that increasing mangrove forest age may promote diversification of bacterial food webs important in N and S cycling. Our results also suggest a potentially important role for sulfur bacteria in supporting the most abundant infaunal consumers, nematodes, in the most mature systems. PMID:17587064

  1. Mangrove loss leads to fish hyperutilization of seagrass beds in a UNESCO biosphere reserve.

    PubMed

    Bologna, P A X

    2014-05-01

    Hurricanes severely damaged a mangrove forest in a UNESCO biosphere reserve in the U.S. Virgin Islands. The system has yet to recover and when alternative habitats have been destroyed, it is shown that juvenile fishes will hyperutilize seagrass beds at densities significantly greater than in areas that maintain functioning mangroves. Despite over a decade of recovery time, the affected mangrove system remains inhospitable to juvenile fishes. PMID:24773547

  2. Food web structure in exotic and native mangroves: A Hawaii-Puerto Rico comparison

    USGS Publications Warehouse

    Demopoulos, A.W.J.; Fry, B.; Smith, C.R.

    2007-01-01

    Plant invasions can fundamentally alter detrital inputs and the structure of detritus-based food webs. We examined the detrital pathways in mangrove food webs in native (Puerto Rican) and introduced (Hawaiian) Rhizophora mangle forests using a dual isotope approach and a mixing model. Based on trophic-level fractionation of 0-1??? for ?? 13C and 2-3??? for ?? 15N, among the invertebrates, only nematodes, oligochaetes, and nereid polychaetes from native mangroves exhibited stable isotopes consistent with a mangrove-derived diet. Certain fauna, in particular tubificid oligochaetes, had ?? 13C values consistent with the consumption of mangrove leaves, but they were depleted in 15N, suggesting their primary nitrogen source was low in 15N, and was possibly N 2-fixing bacteria. In introduced mangroves, all feeding groups appeared to rely heavily on non-mangrove sources, especially phytoplankton inputs. Mixing model results and discriminant analysis showed clear separation of introduced and native mangrove sites based on differential food source utilization within feeding groups, with stronger and more diverse use of benthic foods observed in native forests. Observed differences between native and invasive mangrove food webs may be due to Hawaiian detritivores being poorly adapted to utilizing the tannin-rich, nitrogen-poor mangrove detritus. In addition, differential utilization of mangrove detritus between native and introduced mangroves may be a consequence of forest age. We postulate that increasing mangrove forest age may promote diversification of bacterial food webs important in N and S cycling. Our results also suggest a potentially important role for sulfur bacteria in supporting the most abundant infaunal consumers, nematodes, in the most mature systems. ?? 2007 Springer-Verlag.

  3. Mangrove loss leads to fish hyperutilization of seagrass beds in a UNESCO biosphere reserve.

    PubMed

    Bologna, P A X

    2014-05-01

    Hurricanes severely damaged a mangrove forest in a UNESCO biosphere reserve in the U.S. Virgin Islands. The system has yet to recover and when alternative habitats have been destroyed, it is shown that juvenile fishes will hyperutilize seagrass beds at densities significantly greater than in areas that maintain functioning mangroves. Despite over a decade of recovery time, the affected mangrove system remains inhospitable to juvenile fishes.

  4. Distribution and accumulation of mercury and copper in mangrove sediments in Shenzhen, the world's most rapid urbanized city.

    PubMed

    Li, Ruili; Xu, Hualin; Chai, Minwei; Qiu, Guo Yu

    2016-02-01

    To investigate the influence of mangrove forest on heavy metal accumulation and storage in intertidal sediments, core sediments from natural mangrove, restored mangrove, and adjacent mud flat spanning the intertidal zone along the south coastline of the most heavily urbanized Deep bay, Guangdong province, China were analyzed. The average concentrations of mercury (Hg) in surface sediments of natural mangrove and restored mangrove were 172 and 151 ng g(-1), whereas those of copper (Cu) were 75 and 50 μg g(-1), respectively. Compared to those from other typical mangrove wetlands of the world, the metal levels in Shenzhen were at median to high levels, which is consistent with the fact that Shenzhen is in high exploitation and its mangrove suffer intensive impact from human activities. Hg and Cu concentration profiles indicated a higher metal accumulation in surface layers of sediments, in agreement with enrichment of organic matter contents. Maximum concentration, enrichment factors, and excess (background-deducted) concentration inventories of metals (Hg and Cu) were substantially different between environments, decreasing from natural mangrove sediments to restored mangrove sediments to mud flat. Furthermore, metal inputs to Futian mangrove decreased in the order natural mangrove > restored mangrove > mud flat, indicating that mangrove facilitated the accumulation and storage of Hg and Cu in sediment layers. PMID:26762317

  5. Distribution and accumulation of mercury and copper in mangrove sediments in Shenzhen, the world's most rapid urbanized city.

    PubMed

    Li, Ruili; Xu, Hualin; Chai, Minwei; Qiu, Guo Yu

    2016-02-01

    To investigate the influence of mangrove forest on heavy metal accumulation and storage in intertidal sediments, core sediments from natural mangrove, restored mangrove, and adjacent mud flat spanning the intertidal zone along the south coastline of the most heavily urbanized Deep bay, Guangdong province, China were analyzed. The average concentrations of mercury (Hg) in surface sediments of natural mangrove and restored mangrove were 172 and 151 ng g(-1), whereas those of copper (Cu) were 75 and 50 μg g(-1), respectively. Compared to those from other typical mangrove wetlands of the world, the metal levels in Shenzhen were at median to high levels, which is consistent with the fact that Shenzhen is in high exploitation and its mangrove suffer intensive impact from human activities. Hg and Cu concentration profiles indicated a higher metal accumulation in surface layers of sediments, in agreement with enrichment of organic matter contents. Maximum concentration, enrichment factors, and excess (background-deducted) concentration inventories of metals (Hg and Cu) were substantially different between environments, decreasing from natural mangrove sediments to restored mangrove sediments to mud flat. Furthermore, metal inputs to Futian mangrove decreased in the order natural mangrove > restored mangrove > mud flat, indicating that mangrove facilitated the accumulation and storage of Hg and Cu in sediment layers.

  6. Estimation and Mapping of Coastal Mangrove Biomass Using Both Passive and Active Remote Sensing Method

    NASA Astrophysics Data System (ADS)

    Yiqiong, L.; Lu, W.; Zhou, J.; Gan, W.; Cui, X.; Lin, G., Sr.

    2015-12-01

    Mangrove forests play an important role in global carbon cycle, but carbon stocks in different mangrove forests are not easily measured at large scale. In this research, both active and passive remote sensing methods were used to estimate the aboveground biomass of dominant mangrove communities in Zhanjiang National Mangrove Nature Reserve in Guangdong, China. We set up a decision tree including spectral, texture, position and geometry indexes to achieve mangrove inter-species classification among 5 main species named Aegiceras corniculatum, Aricennia marina, Bruguiera gymnorrhiza, Kandelia candel, Sonneratia apetala by using 5.8m multispectral ZY-3 images. In addition, Lidar data were collected and used to obtain the canopy height of different mangrove species. Then, regression equations between the field measured aboveground biomass and the canopy height deduced from Lidar data were established for these mangrove species. By combining these results, we were able to establish a relatively accurate method for differentiating mangrove species and mapping their aboveground biomass distribution at the estuary scale, which could be applied to mangrove forests in other regions.

  7. Estimating tree growth from complex forest monitoring data.

    PubMed

    Eitzel, Melissa; Battles, John; York, Robert; Knape, Jonas; de Valpine, Perry

    2013-09-01

    Understanding tree growth as a function of tree size is important for a multitude of ecological and management applications. Determining what limits growth is of central interest, and forest inventory permanent plots are an abundant source of long-term information but are highly complex. Observation error and multiple sources of shared variation (spatial plot effects, temporal repeated measures, and a mosaic of sampling intervals) make these data challenging to use for growth estimation. We account for these complexities and incorporate potential limiting factors (tree size, competition, and resource supply) into a hierarchical state-space model. We estimate the diameter growth of white fir (Abies concolor) in the Sierra Nevada of California from forest inventory data, showing that estimating such a model is feasible in a Bayesian framework using readily available modeling tools. In this forest, white fir growth depends strongly on tree size, total plot basal area, and unexplained variation between individual trees. Plot-level resource supply variables (representing light, water, and nutrient availability) do not have a strong impact on inventory-size trees. This approach can be applied to other networks of permanent forest plots, leading to greater ecological insights on tree growth.

  8. Consolidating new paradigms in large-scale monitoring and assessment of forest ecosystems.

    PubMed

    Corona, Piermaria

    2016-01-01

    Forests provide a wide range of ecosystem services from which people benefit, and upon which all life depends. However, any rational decision related to the maintenance and enhancement of the multiple functions provided by the forests needs to be based on objective, reliable information. As such, forest monitoring and assessment are rapidly evolving as new information needs arise or new techniques and tools become available. Global change issues and utilities from ecosystem management are distinctively to be considered, so that forest inventory and mapping are broadening their scope towards multipurpose resources surveys. Recent changes in forest management perspective have promoted the consideration of forests as complex adaptive systems, thereby highlighting the need to account that such approaches actually work: forest monitoring and assessment are then expected to address and fully incorporate this perspective at global scale, seeking to support planning and management decisions that are evidence-based. This contribution provides selected considerations on the above mentioned issues, in the form of a commented discussion with examples from the literature produced in the last decade. PMID:26514075

  9. Consolidating new paradigms in large-scale monitoring and assessment of forest ecosystems.

    PubMed

    Corona, Piermaria

    2016-01-01

    Forests provide a wide range of ecosystem services from which people benefit, and upon which all life depends. However, any rational decision related to the maintenance and enhancement of the multiple functions provided by the forests needs to be based on objective, reliable information. As such, forest monitoring and assessment are rapidly evolving as new information needs arise or new techniques and tools become available. Global change issues and utilities from ecosystem management are distinctively to be considered, so that forest inventory and mapping are broadening their scope towards multipurpose resources surveys. Recent changes in forest management perspective have promoted the consideration of forests as complex adaptive systems, thereby highlighting the need to account that such approaches actually work: forest monitoring and assessment are then expected to address and fully incorporate this perspective at global scale, seeking to support planning and management decisions that are evidence-based. This contribution provides selected considerations on the above mentioned issues, in the form of a commented discussion with examples from the literature produced in the last decade.

  10. Snow, Forests, and Disturbance: Monitoring Along an Elevation Transect in the Oregon Cascades

    NASA Astrophysics Data System (ADS)

    Nolin, A. W.; Roth, T.; Gleason, K.

    2012-12-01

    Maritime snowpacks in the Pacific Northwest are strongly influenced by the effects of temperature and forest canopy. In this climatically sensitive region, snow accumulates close to the melting point throughout the winter and rain on snow is a common winter occurrence, especially at elevations below 1000 m. Forest structure and canopy density strongly affect patterns of snow accumulation and melt. The primary disturbance regimes in this region are forest management practices and wildfire. In fall 2011, we established a network of snow monitoring sites that sample a range of snow classes as defined by elevation, vegetation type, and vegetation density. At each site we have installed a meteorological tower to monitor snow energy balance and we perform monthly snow surveys during the accumulation season and bi-monthly surveys during the ablation season. The sites include Old Growth, clear cut, second growth, thinned forest, burned/recovering forest, and recently burned forest. In this presentation we evaluate and quantify the effect of forest canopy on snow accumulation and the relative magnitudes of energy balance components contributing to ablation. We also identify the decreased snow albedo in wildfire affected areas as a significant contributor to early melt.

  11. Methyl halide emissions from greenhouse-grown mangroves

    NASA Astrophysics Data System (ADS)

    Manley, Steven L.; Wang, Nun-Yii; Walser, Maggie L.; Cicerone, Ralph J.

    2007-01-01

    Two mangrove species, Avicennia germinans and Rhizophora mangle, were greenhouse grown for nearly 1.5 years from saplings. A single individual of each species was monitored for the emission of methyl halides from aerial tissue. During the first 240 days, salinity was incrementally increased with the addition of seawater, and was maintained between 18 and 28‰ for the duration of the study. Exponential growth occurred after 180 days. Methyl halide emissions normalized to leaf area were measured throughout the study and varied dramatically. Emission rates normalized to land area (mg m-2 y-1), assuming a LAI = 5, yielded 82 and 29 for CH3Cl, 10 and 1.6 for CH3Br, and 26 and 11 for CH3I, for A. germinans and R. mangle, respectively. From these preliminary determinations, only CH3I emissions emerge as being of possible global atmospheric significance. This study emphasizes the need for field studies of methyl halide emissions from mangrove forests.

  12. A framework for assessment and monitoring of small mammals in a lowland tropical forest.

    PubMed

    Solari, Sergio; Rodriguez, Juan José; Vivar, Elena; Velazco, Paul M

    2002-05-01

    Development projects in tropical forests can impact biodiversity. Assessment and monitoring programs based on the principles of adaptive management assist managers to identify and reduce such impacts. The small mammal community is one important component of a forest ecosystem that may be impacted by development projects. In 1996, a natural gas exploration project was initiated in a Peruvian rainforest. The Smithsonian Institution's Monitoring and Assessment of Biodiversity program cooperated with Shell Prospecting and Development Peru to establish an adaptive management program to protect the region's biodiversity. In this article, we discuss the role of assessing and monitoring small mammals in relation to the natural gas project. We outline the conceptual issues involved in establishing an assessment and monitoring program, including setting objectives, evaluating the results and making appropriate decisions. We also summarize the steps taken to implement the small mammal assessment, provide results from the assessment and discuss protocols to identify appropriate species for monitoring. PMID:12125752

  13. Nitrate ammonification in mangrove soils: a hidden source of nitrite?

    PubMed Central

    Balk, Melike; Laverman, Anniet M.; Keuskamp, Joost A.; Laanbroek, Hendrikus J.

    2015-01-01

    Nitrate reduction is considered to be a minor microbial pathway in the oxidation of mangrove-derived organic matter due to a limited supply of nitrate in mangrove soils. At a limited availability of this electron acceptor compared to the supply of degradable carbon, nitrate ammonification is thought to be the preferential pathway of nitrate reduction. Mangrove forest mutually differ in their productivity, which may lead to different available carbon to nitrate ratios in their soil. Hence, nitrate ammonification is expected to be of more importance in high- compared to low-productive forests. The hypothesis was tested in flow-through reactors that contain undisturbed mangrove soils from high-productive Avicennia germinans and Rhizophora mangle forests in Florida and low-productive Avicennia marina forests in Saudi Arabia. Nitrate was undetectable in the soils from both regions. It was assumed that a legacy of nitrate ammonification would be reflected by a higher ammonium production from these soils upon the addition of nitrate. Unexpectedly, the soils from the low-productive forests in Saudi Arabia produced considerably more ammonium than the soils from the high-productive forests in Florida. Hence, other environmental factors than productivity must govern the selection of nitrate ammonification or denitrification. A rather intriguing observation was the 1:1 production of nitrite and ammonium during the consumption of nitrate, more or less independent from sampling region, location, sampling depth, mangrove species and from the absence or presence of additional degradable carbon. This 1:1 ratio points to a coupled production of ammonium and nitrite by one group of nitrate-reducing microorganisms. Such a production of nitrite will be hidden by the presence of active nitrite-reducing microorganisms under the nitrate-limited conditions of most mangrove forest soils. PMID:25784903

  14. Nitrate ammonification in mangrove soils: a hidden source of nitrite?

    PubMed

    Balk, Melike; Laverman, Anniet M; Keuskamp, Joost A; Laanbroek, Hendrikus J

    2015-01-01

    Nitrate reduction is considered to be a minor microbial pathway in the oxidation of mangrove-derived organic matter due to a limited supply of nitrate in mangrove soils. At a limited availability of this electron acceptor compared to the supply of degradable carbon, nitrate ammonification is thought to be the preferential pathway of nitrate reduction. Mangrove forest mutually differ in their productivity, which may lead to different available carbon to nitrate ratios in their soil. Hence, nitrate ammonification is expected to be of more importance in high- compared to low-productive forests. The hypothesis was tested in flow-through reactors that contain undisturbed mangrove soils from high-productive Avicennia germinans and Rhizophora mangle forests in Florida and low-productive Avicennia marina forests in Saudi Arabia. Nitrate was undetectable in the soils from both regions. It was assumed that a legacy of nitrate ammonification would be reflected by a higher ammonium production from these soils upon the addition of nitrate. Unexpectedly, the soils from the low-productive forests in Saudi Arabia produced considerably more ammonium than the soils from the high-productive forests in Florida. Hence, other environmental factors than productivity must govern the selection of nitrate ammonification or denitrification. A rather intriguing observation was the 1:1 production of nitrite and ammonium during the consumption of nitrate, more or less independent from sampling region, location, sampling depth, mangrove species and from the absence or presence of additional degradable carbon. This 1:1 ratio points to a coupled production of ammonium and nitrite by one group of nitrate-reducing microorganisms. Such a production of nitrite will be hidden by the presence of active nitrite-reducing microorganisms under the nitrate-limited conditions of most mangrove forest soils.

  15. Tropical forest cover change in the 1990s and options for future monitoring.

    PubMed

    Mayaux, Philippe; Holmgren, Peter; Achard, Frédéric; Eva, Hugh; Stibig, Hans-Jürgen; Branthomme, Anne

    2005-02-28

    Despite the importance of the world's humid tropical forests, our knowledge concerning their rates of change remains limited. Two recent programmes (FAO 2000 Forest Resources Assessment and TREES II), exploiting the global imaging capabilities of Earth observing satellites, have recently been completed to provide information on the dynamics of tropical forest cover. The results from these independent studies show a high degree of conformity and provide a good understanding of trends at the pan-tropical level. In 1990 there were some 1150 million ha of tropical rain forest with the area of the humid tropics deforested annually estimated at 5.8 million ha (approximately twice the size of Belgium). A further 2.3 million ha of humid forest is apparently degraded annually through fragmentation, logging and/or fires. In the sub-humid and dry tropics, annual deforestation of tropical moist deciduous and tropical dry forests comes to 2.2 and 0.7 million ha, respectively. Southeast Asia is the region where forests are under the highest pressure with an annual change rate of -0.8 to -0.9%. The annual area deforested in Latin America is large, but the relative rate (-0.4 to -0.5%) is lower, owing to the vast area covered by the remaining Amazonian forests. The humid forests of Africa are being converted at a similar rate to those of Latin America (-0.4 to -0.5% per year). During this period, secondary forests have also been established, through re-growth on abandoned land and forest plantations, but with different ecological, biophysical and economic characteristics compared with primary forests. These trends are significant in all regions, but the extent of new forest cover has proven difficult to establish. These results, as well as the lack of more detailed knowledge, clearly demonstrate the need to improve sound scientific evidence to support policy. The two projects provide useful guidance for future monitoring efforts in the context of multilateral environmental

  16. A Project to Map and Monitor Baldcypress Forests in Coastal Louisiana, Using Landsat, MODIS, and ASTER Satellite Data

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Sader, Steven; Smoot, James

    2012-01-01

    Cypress swamp forests of Louisiana offer many important ecological and economic benefits: wildlife habitat, forest products, storm buffers, water quality, and recreation. Such forests are also threatened by multiple factors: subsidence, salt water intrusion, sea level rise, persistent flooding, hydrologic modification, hurricanes, insect and nutria damage, timber harvesting, and land use conversion. Unfortunately, there are many information gaps regarding the type, location, extent, and condition of these forests. Better more up to date swamp forest mapping products are needed to aid coastal forest conservation and restoration work (e.g., through the Coastal Forest Conservation Initiative or CFCI). In response, a collaborative project was initiated to develop, test and demonstrate cypress swamp forest mapping products, using NASA supported Landsat, ASTER, and MODIS satellite data. Research Objectives are: Develop, test, and demonstrate use of Landsat and ASTER data for computing new cypress forest classification products and Landsat, ASTER, and MODIS satellite data for detecting and monitoring swamp forest change

  17. Monitoring nitrogen accumulation in mosses in central European forests.

    PubMed

    Pesch, Roland; Schröder, Winfried; Schmidt, Gunther; Genssler, Lutz

    2008-10-01

    In order to assess whether nitrogen (N) loads in mosses reflect different land uses, 143 sites in North Rhine-Westphalia, the Weser-Ems Region and the Euro Region Nissa were sampled between 2000 and 2005. The data were analysed statistically with available surface information on land use and forest conditions. N bioaccumulation in mosses in the Weser-Ems Region with high densities of agricultural land use and livestock exceeded the concentrations in the more industrialised Euro Region Nissa. In all three study areas agricultural and livestock spatial densities were found to be positively correlated with N bioaccumulation in mosses. In North Rhine-Westphalia, the N concentrations in mosses was also moderately correlated with N concentrations in leaves and needles of forest trees. The moss method proved useful to assess the spatial patterns of N bioaccumulation due to land use.

  18. Surface Elevation Change And Vertical Accretion In Created Mangroves In Tampa Bay, Florida, Usa

    EPA Science Inventory

    Mangroves protect coastlines, provide faunal habitat, and store large quantities of carbon (C). In South Florida and other parts of the Gulf of Mexico, large wetland areas, including mangrove forests, have been removed, degraded, or damaged. Wetland creation efforts have been use...

  19. Assessing relatedness and redundancy of forest monitoring and change indicators.

    PubMed

    Nagendra, Harini

    2012-03-01

    Information on changes in forest structure and composition is required for informed, adaptive management and conservation. As the collection of such information requires field studies that are expensive, difficult, and time consuming, the prioritization of metrics can be of significant value. This study evaluates a number of metrics used to assess changes in forest structure and composition for a set of 59 forests in five countries - Kenya, India, Nepal, Uganda and USA. Changes in tree density are significantly positively correlated with changes in species richness, and changes in sapling/shrub density are significantly positively correlated with changes in species richness. Thus, rapid assessments of tree density change can be used to prioritize locations where there may be rapid deterioration in tree diversity, where the collection of detailed information on changes in species composition may be prioritized. Changes in tree density do not reflect changes in shrub and sapling density. The shrub and sapling layer appears to respond differently to human or natural disturbances compared to the tree layer, and may require separate assessment. Changes in tree DBH and tree height are not completely congruent, indicating that measurements of DBH and height may be required to accurately estimate changes in above ground carbon storage over time, for programs such as REDD that provide payment for carbon sequestration services. PMID:22115515

  20. Chemical and biogeophysical impact of four-dimensional (4D) seismic exploration in sub-Saharan Africa, and restoration of dysfunctionalized mangrove forests in the prospect areas.

    PubMed

    Osuji, Leo C; Ayolagha, G; Obute, G C; Ohabuike, H C

    2007-09-01

    Four-dimensional (4D) seismic exploration, an improved geophysical technique for hydrocarbon-data acquisition, was applied for the first time in the Nembe Creek prospect area of Nigeria. The affected soils were slightly alkaline in situ when wet (pH 7.2), but extremely acidic when dry (pH 3.0). The organic carbon content (4.6-26.8%) and other physicochemical properties of soils and water (N, P, and heavy-metal contents, etc.) were higher than the baseline values obtained in 2001 before seismic profiling. Most values also exceeded the baseline compliance standards of the Department of Petroleum Resources (DPR), the World Health Organization (WHO), and the Federal Environmental Protection Agency (FEPA). Rehabilitation of the affected areas was achieved by stabilizing the mangrove floor by liming and appropriate application of nutrients, followed by replanting the cut seismic lines over a distance of 1,372 km with different mangrove species, including juvenile Rhizophora racemosa, R. mangle, and Avicennia species, which were transferred from nursery points. Quicker post-operational intervention is recommended for future 4D surveys, because the time lag between the end of seismic activity and post-impact investigation is critical in determining the relationship between activity and impact: the longer the intervening period, the more mooted the interaction. PMID:17886833

  1. Monitoring population and land use change in tropical forest protected areas

    NASA Astrophysics Data System (ADS)

    Zvoleff, A. I.; Rosa, M.; Ahumada, J. A.

    2014-12-01

    Monitoring human-environment interactions in tropical forest protected areas requires linking interdisciplinary datasets collected across a range of spatial and temporal scales. Recent assessments have shown that forest degradation and loss outside of protected areas is strongly associated with declines in biodiversity within protected areas. Biodiversity monitoring efforts must therefore develop approaches that consider change in the broader landscape, using biophysical and socioeconomic datasets that not only cover the extent of a protected area, but also the region surrounding it. The Tropical Ecology Assessment and Monitoring (TEAM) Network has developed an approach for linking remotely sensed imagery from Landsat and MODIS sensors with in-situ ecological data and socioeconomic datasets to better understand the effects of landscape change on biodiversity. The TEAM Network is a global system for monitoring biodiversity, land use/cover change (LUCC), and climate in sixteen tropical forest sites evenly distributed across global biophysical gradients (rainfall and seasonality) and gradients of expected climate change and land use change. TEAM adopts the Zone of Interaction (ZOI) concept to delineate the spatial extent around protected areas for linking broader-scale trends in LUCC to plot-based monitoring data. This talk reports on a cross-site comparison examining LUCC and biodiversity change across the TEAM network. The analysis indicates a gradient of forest loss in the tropics dependent on landscape-level human factors, such as population and road density. The highest losses of forest cover are associated with changing patterns of land use and agricultural development, particularly plantation forestry in Southeast Asia. While the spatial and temporal resolution of remote sensing-derived datasets continues to increase, a key challenge for monitoring efforts is linking this data to spatially explicit socioeconomic datasets for use in statistical modeling. We will

  2. Sample project: establishing a global forest monitoring capability using multi-resolution and multi-temporal remotely sensed data sets

    USGS Publications Warehouse

    Hansen, Matt; Stehman, Steve; Loveland, Tom; Vogelmann, Jim; Cochrane, Mark

    2009-01-01

    Quantifying rates of forest-cover change is important for improved carbon accounting and climate change modeling, management of forestry and agricultural resources, and biodiversity monitoring. A practical solution to examining trends in forest cover change at global scale is to employ remotely sensed data. Satellite-based monitoring of forest cover can be implemented consistently across large regions at annual and inter-annual intervals. This research extends previous research on global forest-cover dynamics and land-cover change estimation to establish a robust, operational forest monitoring and assessment system. The approach integrates both MODIS and Landsat data to provide timely biome-scale forest change estimation. This is achieved by using annual MODIS change indicator maps to stratify biomes into low, medium and high change categories. Landsat image pairs can then be sampled within these strata and analyzed for estimating area of forest cleared.

  3. Modelling the impacts of sea level rise on tidal basin ecomorphodynamics and mangrove habitat evolution

    NASA Astrophysics Data System (ADS)

    van Maanen, Barend; Coco, Giovanni; Bryan, Karin

    2016-04-01

    The evolution of tidal basins and estuaries in tropical and subtropical regions is often influenced by the presence of mangrove forests. These forests are amongst the most productive environments in the world and provide important ecosystem services. However, these intertidal habitats are also extremely vulnerable and are threatened by climate change impacts such as sea level rise. It is therefore of key importance to improve our understanding of how tidal systems occupied by mangrove vegetation respond to rising water levels. An ecomorphodynamic model was developed that simulates morphological change and mangrove forest evolution as a result of mutual feedbacks between physical and biological processes. The model accounts for the effects of mangrove trees on tidal flow patterns and sediment dynamics. Mangrove growth is in turn controlled by hydrodynamic conditions. Under stable water levels, model results indicate that mangrove trees enhance the initiation and branching of tidal channels, partly because the extra flow resistance in mangrove forests favours flow concentration, and thus sediment erosion in between vegetated areas. The landward expansion of the channels, on the other hand, is reduced. Model simulations including sea level rise suggest that mangroves can potentially enhance the ability of the soil surface to maintain an elevation within the upper portion of the intertidal zone. While the sea level is rising, mangroves are migrating landward and the channel network tends to expand landward too. The presence of mangrove trees, however, was found to hinder both the branching and headward erosion of the landward expanding channels. Simulations are performed according to different sea level rise scenarios and with different tidal range conditions to assess which tidal environments are most vulnerable. Changes in the properties of the tidal channel networks are being examined as well. Overall, model results highlight the role of mangroves in driving the

  4. Spatial heterogeneity and kinetic regulation of arsenic dynamics in mangrove sediments: the Sundarbans, Bangladesh.

    PubMed

    Sumon, Mahmud H; Hossain, Mahmud; Williams, Paul N; Mestrot, Adrien; Norton, Gareth J; Deacon, Claire M; Meharg, Andrew A

    2012-08-21

    The biogeochemistry of arsenic (As) in sediments is regulated by multiple factors such as particle size, dissolved organic matter (DOM), iron mobilization, and sediment binding characteristics, among others. Understanding the heterogeneity of factors affecting As deposition and the kinetics of mobilization, both horizontally and vertically, across sediment depositional environments was investigated in Sundarban mangrove ecosystems, Bengal Delta, Bangladesh. Sediment cores were collected from 3 different Sundarbans locations and As concentration down the profiles were found to be more associated with elevated Fe and Mn than with organic matter (OM). At one site chosen for field monitoring, sediment cores, pore and surface water, and in situ diffusive gradients in thin films (DGT) measurements (which were used to model As sediment pore-water concentrations and resupply from the solid phase) were sampled from four different subhabitats. Coarse-textured riverbank sediment porewaters were high in As, but with a limited resupply of As from the solid phase compared to fine-textured and high organic matter content forest floor sediments, where porewater As was low, but with much higher As resupply. Depositional environment (overbank verses forest floor) and biological activity (input of OM from forest biomass) considerably affected As dynamics over very short spatial distances in the mosaic of microhabitats that constitute a mangrove ecosystem.

  5. Monitoring forest disturbances in Southeast Oklahoma using Landsat and MODIS images

    NASA Astrophysics Data System (ADS)

    Tran, Trung V.; de Beurs, Kirsten M.; Julian, Jason P.

    2016-02-01

    Monitoring forest disturbances using remote sensing data with high spatial and temporal resolution can reveal relationships between forest disturbances and forest ecological patterns and processes. In this study, we fused Landsat data at high spatial resolution (30 m) with 8-day MODIS data to produce high spatial and temporal resolution image time-series. The Spatial Temporal Adaptive Algorithm for mapping Reflectance Change (STAARCH) is a simple but effective fusion method. We adapted the STAARCH fusion method to successfully produce a time-series of disturbances with high overall accuracy (89-92%) in mixed forests in southeast Oklahoma. The results demonstrated that in southeast Oklahoma, forest area disturbed in 2011 was higher than it was in 2000. However, two remarkable drops were identified in 2001 and 2006. We speculated that the drops were related to the economic recessions causing reduction in the demand of woody products. The detected fluctuation of area disturbed calls for continuing monitoring of spatial and temporal changes in this and other forest landscapes using high spatial and temporal resolution imagery datasets to better recognize the economic and environmental factors, as well as the consequences of those changes.

  6. Design and Implementation of an Interactive Web-Based Near Real-Time Forest Monitoring System.

    PubMed

    Pratihast, Arun Kumar; DeVries, Ben; Avitabile, Valerio; de Bruin, Sytze; Herold, Martin; Bergsma, Aldo

    2016-01-01

    This paper describes an interactive web-based near real-time (NRT) forest monitoring system using four levels of geographic information services: 1) the acquisition of continuous data streams from satellite and community-based monitoring using mobile devices, 2) NRT forest disturbance detection based on satellite time-series, 3) presentation of forest disturbance data through a web-based application and social media and 4) interaction of the satellite based disturbance alerts with the end-user communities to enhance the collection of ground data. The system is developed using open source technologies and has been implemented together with local experts in the UNESCO Kafa Biosphere Reserve, Ethiopia. The results show that the system is able to provide easy access to information on forest change and considerably improves the collection and storage of ground observation by local experts. Social media leads to higher levels of user interaction and noticeably improves communication among stakeholders. Finally, an evaluation of the system confirms the usability of the system in Ethiopia. The implemented system can provide a foundation for an operational forest monitoring system at the national level for REDD+ MRV applications.

  7. Design and Implementation of an Interactive Web-Based Near Real-Time Forest Monitoring System

    PubMed Central

    Pratihast, Arun Kumar; DeVries, Ben; Avitabile, Valerio; de Bruin, Sytze; Herold, Martin; Bergsma, Aldo

    2016-01-01

    This paper describes an interactive web-based near real-time (NRT) forest monitoring system using four levels of geographic information services: 1) the acquisition of continuous data streams from satellite and community-based monitoring using mobile devices, 2) NRT forest disturbance detection based on satellite time-series, 3) presentation of forest disturbance data through a web-based application and social media and 4) interaction of the satellite based disturbance alerts with the end-user communities to enhance the collection of ground data. The system is developed using open source technologies and has been implemented together with local experts in the UNESCO Kafa Biosphere Reserve, Ethiopia. The results show that the system is able to provide easy access to information on forest change and considerably improves the collection and storage of ground observation by local experts. Social media leads to higher levels of user interaction and noticeably improves communication among stakeholders. Finally, an evaluation of the system confirms the usability of the system in Ethiopia. The implemented system can provide a foundation for an operational forest monitoring system at the national level for REDD+ MRV applications. PMID:27031694

  8. Design and Implementation of an Interactive Web-Based Near Real-Time Forest Monitoring System.

    PubMed

    Pratihast, Arun Kumar; DeVries, Ben; Avitabile, Valerio; de Bruin, Sytze; Herold, Martin; Bergsma, Aldo

    2016-01-01

    This paper describes an interactive web-based near real-time (NRT) forest monitoring system using four levels of geographic information services: 1) the acquisition of continuous data streams from satellite and community-based monitoring using mobile devices, 2) NRT forest disturbance detection based on satellite time-series, 3) presentation of forest disturbance data through a web-based application and social media and 4) interaction of the satellite based disturbance alerts with the end-user communities to enhance the collection of ground data. The system is developed using open source technologies and has been implemented together with local experts in the UNESCO Kafa Biosphere Reserve, Ethiopia. The results show that the system is able to provide easy access to information on forest change and considerably improves the collection and storage of ground observation by local experts. Social media leads to higher levels of user interaction and noticeably improves communication among stakeholders. Finally, an evaluation of the system confirms the usability of the system in Ethiopia. The implemented system can provide a foundation for an operational forest monitoring system at the national level for REDD+ MRV applications. PMID:27031694

  9. Mangrove succession enriches the sediment microbial community in South China.

    PubMed

    Chen, Quan; Zhao, Qian; Li, Jing; Jian, Shuguang; Ren, Hai

    2016-01-01

    Sediment microorganisms help create and maintain mangrove ecosystems. Although the changes in vegetation during mangrove forest succession have been well studied, the changes in the sediment microbial community during mangrove succession are poorly understood. To investigate the changes in the sediment microbial community during succession of mangroves at Zhanjiang, South China, we used phospholipid fatty acid (PLFA) analysis and the following chronosequence from primary to climax community: unvegetated shoal; Avicennia marina community; Aegiceras corniculatum community; and Bruguiera gymnorrhiza + Rhizophora stylosa community. The PLFA concentrations of all sediment microbial groups (total microorganisms, fungi, gram-positive bacteria, gram-negative bacteria, and actinomycetes) increased significantly with each stage of mangrove succession. Microbial PLFA concentrations in the sediment were significantly lower in the wet season than in the dry season. Regression and ordination analyses indicated that the changes in the microbial community with mangrove succession were mainly associated with properties of the aboveground vegetation (mainly plant height) and the sediment (mainly sediment organic matter and total nitrogen). The changes in the sediment microbial community can probably be explained by increases in nutrients and microhabitat heterogeneity during mangrove succession. PMID:27265262

  10. Mangrove succession enriches the sediment microbial community in South China

    PubMed Central

    Chen, Quan; Zhao, Qian; Li, Jing; Jian, Shuguang; Ren, Hai

    2016-01-01

    Sediment microorganisms help create and maintain mangrove ecosystems. Although the changes in vegetation during mangrove forest succession have been well studied, the changes in the sediment microbial community during mangrove succession are poorly understood. To investigate the changes in the sediment microbial community during succession of mangroves at Zhanjiang, South China, we used phospholipid fatty acid (PLFA) analysis and the following chronosequence from primary to climax community: unvegetated shoal; Avicennia marina community; Aegiceras corniculatum community; and Bruguiera gymnorrhiza + Rhizophora stylosa community. The PLFA concentrations of all sediment microbial groups (total microorganisms, fungi, gram-positive bacteria, gram-negative bacteria, and actinomycetes) increased significantly with each stage of mangrove succession. Microbial PLFA concentrations in the sediment were significantly lower in the wet season than in the dry season. Regression and ordination analyses indicated that the changes in the microbial community with mangrove succession were mainly associated with properties of the aboveground vegetation (mainly plant height) and the sediment (mainly sediment organic matter and total nitrogen). The changes in the sediment microbial community can probably be explained by increases in nutrients and microhabitat heterogeneity during mangrove succession. PMID:27265262

  11. Mangrove succession enriches the sediment microbial community in South China.

    PubMed

    Chen, Quan; Zhao, Qian; Li, Jing; Jian, Shuguang; Ren, Hai

    2016-06-06

    Sediment microorganisms help create and maintain mangrove ecosystems. Although the changes in vegetation during mangrove forest succession have been well studied, the changes in the sediment microbial community during mangrove succession are poorly understood. To investigate the changes in the sediment microbial community during succession of mangroves at Zhanjiang, South China, we used phospholipid fatty acid (PLFA) analysis and the following chronosequence from primary to climax community: unvegetated shoal; Avicennia marina community; Aegiceras corniculatum community; and Bruguiera gymnorrhiza + Rhizophora stylosa community. The PLFA concentrations of all sediment microbial groups (total microorganisms, fungi, gram-positive bacteria, gram-negative bacteria, and actinomycetes) increased significantly with each stage of mangrove succession. Microbial PLFA concentrations in the sediment were significantly lower in the wet season than in the dry season. Regression and ordination analyses indicated that the changes in the microbial community with mangrove succession were mainly associated with properties of the aboveground vegetation (mainly plant height) and the sediment (mainly sediment organic matter and total nitrogen). The changes in the sediment microbial community can probably be explained by increases in nutrients and microhabitat heterogeneity during mangrove succession.

  12. Damage and recovery assessment of the Philippines' mangroves following Super Typhoon Haiyan.

    PubMed

    Long, Jordan; Giri, Chandra; Primavera, Jurgenne; Trivedi, Mandar

    2016-08-30

    We quantified mangrove disturbance resulting from Super Typhoon Haiyan using a remote sensing approach. Mangrove areas were mapped prior to Haiyan using 30m Landsat imagery and a supervised decision-tree classification. A time sequence of 250m eMODIS data was used to monitor mangrove condition prior to, and following, Haiyan. Based on differences in eMODIS NDVI observations before and after the storm, we classified mangrove into three damage level categories: minimal, moderate, or severe. Mangrove damage in terms of extent and severity was greatest where Haiyan first made landfall on Eastern Samar and Western Samar provinces and lessened westward corresponding with decreasing storm intensity as Haiyan tracked from east to west across the Visayas region of the Philippines. However, within 18months following Haiyan, mangrove areas classified as severely, moderately, and minimally damaged decreased by 90%, 81%, and 57%, respectively, indicating mangroves resilience to powerful typhoons. PMID:27394635

  13. Damage and recovery assessment of the Philippines' mangroves following Super Typhoon Haiyan.

    PubMed

    Long, Jordan; Giri, Chandra; Primavera, Jurgenne; Trivedi, Mandar

    2016-08-30

    We quantified mangrove disturbance resulting from Super Typhoon Haiyan using a remote sensing approach. Mangrove areas were mapped prior to Haiyan using 30m Landsat imagery and a supervised decision-tree classification. A time sequence of 250m eMODIS data was used to monitor mangrove condition prior to, and following, Haiyan. Based on differences in eMODIS NDVI observations before and after the storm, we classified mangrove into three damage level categories: minimal, moderate, or severe. Mangrove damage in terms of extent and severity was greatest where Haiyan first made landfall on Eastern Samar and Western Samar provinces and lessened westward corresponding with decreasing storm intensity as Haiyan tracked from east to west across the Visayas region of the Philippines. However, within 18months following Haiyan, mangrove areas classified as severely, moderately, and minimally damaged decreased by 90%, 81%, and 57%, respectively, indicating mangroves resilience to powerful typhoons.

  14. Monitoring forest change at ecotones in the Colorado Rockies

    SciTech Connect

    Stohlgren, T.J.; Bachand, R.R. )

    1994-06-01

    We are assessing the potential effect of global climate change on the Front Range of the Colorado Rockies, including Rocky Mountain National Park. Our objective is quantify the abiotic and biotic controls on forest distribution and productivity as a basis for assessing potential vegetation change for a range of projected climate scenarios. A series of long-term vegetation transects are being established to relate soil characteristics (e.g., soil type, texture, moisture, nitrogen content) and microclimate (air and soil temperature) to vegetation characteristics (e.g., basal area, leaf area index, tree age structure, resource use efficiency, primary production) across lodgepole pine (Pinus contorta var. latifolia) ecotones. Results from five 200+ ectonal transects (68 20 m x 20 m plots; over 3,753 trees) show that basal area gradients from lodgepole pine to spruce-fir (Picea engelmannii, Abies lasiocarpa), ponderosa pine (Pinus ponderosa), and limber pine (Pinus flexilis) forests are correlated strongly (but not linearly), to soil texture and summer soil moisture. Factors controlling species-specific radial growth patterns along ecotones are more complex.

  15. Forest health monitoring: Southeast loblolly/shortleaf pine demonstration interim report

    SciTech Connect

    Lewis, T.E.; Conkling, B.L.

    1994-04-01

    The U.S. Environmental Protection Agency's Office of Research and Development is conducting an Environmental Monitoring and Assessment Program (EMAP) with other federal agencies to establish the status of and trends in the ecological health of the Nation's natural resources. The forest component of EMAP is a multiagency effort referred to as Forest Health Monitoring (FHM). The FHM program conducted a two year demonstration study to test a suite of indicators considered important in assessing forest health. The study is referred to in this report as the Southeast Loblolly/Shortleaf Pine Demonstration, or SE DEMO. The interim report describes the results from the first year of the SE DEMO. The use of such data is encouraged by EMAP to foster a better understanding of the anticipated performance of an indicator prior to large investments in funding for field research. These data were used to the extent possible to determine the current status of each indicator with respect to the six criteria.

  16. Optimization of the information content of multitemporal Landsat TM data sets for monitoring forest cover disturbance

    NASA Technical Reports Server (NTRS)

    Coppin, Pol R.; Bauer, Marvin E.

    1992-01-01

    Procedures that were developed to optimize the information content of multitemporal thematic mapper (TM) data sets for forest cover disturbance monitoring in Minnesota are described. TM imagery from three different years was calibrated to exoatmospheric reflectance. An atmospheric correction routine was applied combining two major components, atmospheric normalization over time and transformation to ground reflectance. Atmospheric conditions were modeled over time using regression functions derived from five ground features known to be unchanged over the time interval of interest and spanning the entire image reflectance range. The correlation between digital data and the forest cover was subsequently maximized and irrelevant information content was reduced by converting the band-specific reflectances into seven vegetation indices that were assumed to carry unique information. The application of two change detection algorithms to these seven indices ultimately resulted in 14 change features for each time interval of interest. Results show that the preprocessing sequence is vital to forest cover monitoring methodology.

  17. Conditional cooperation and costly monitoring explain success in forest commons management.

    PubMed

    Rustagi, Devesh; Engel, Stefanie; Kosfeld, Michael

    2010-11-12

    Recent evidence suggests that prosocial behaviors like conditional cooperation and costly norm enforcement can stabilize large-scale cooperation for commons management. However, field evidence on the extent to which variation in these behaviors among actual commons users accounts for natural commons outcomes is altogether missing. Here, we combine experimental measures of conditional cooperation and survey measures on costly monitoring among 49 forest user groups in Ethiopia with measures of natural forest commons outcomes to show that (i) groups vary in conditional cooperator share, (ii) groups with larger conditional cooperator share are more successful in forest commons management, and (iii) costly monitoring is a key instrument with which conditional cooperators enforce cooperation. Our findings are consistent with models of gene-culture coevolution on human cooperation and provide external validity to laboratory experiments on social dilemmas.

  18. Monitoring forest dynamics with multi-scale and time series imagery.

    PubMed

    Huang, Chunbo; Zhou, Zhixiang; Wang, Di; Dian, Yuanyong

    2016-05-01

    To learn the forest dynamics and evaluate the ecosystem services of forest effectively, a timely acquisition of spatial and quantitative information of forestland is very necessary. Here, a new method was proposed for mapping forest cover changes by combining multi-scale satellite remote-sensing imagery with time series data. Using time series Normalized Difference Vegetation Index products derived from the Moderate Resolution Imaging Spectroradiometer images (MODIS-NDVI) and Landsat Thematic Mapper/Enhanced Thematic Mapper Plus (TM/ETM+) images as data source, a hierarchy stepwise analysis from coarse scale to fine scale was developed for detecting the forest change area. At the coarse scale, MODIS-NDVI data with 1-km resolution were used to detect the changes in land cover types and a land cover change map was constructed using NDVI values at vegetation growing seasons. At the fine scale, based on the results at the coarse scale, Landsat TM/ETM+ data with 30-m resolution were used to precisely detect the forest change location and forest change trend by analyzing time series forest vegetation indices (IFZ). The method was tested using the data for Hubei Province, China. The MODIS-NDVI data from 2001 to 2012 were used to detect the land cover changes, and the overall accuracy was 94.02 % at the coarse scale. At the fine scale, the available TM/ETM+ images at vegetation growing seasons between 2001 and 2012 were used to locate and verify forest changes in the Three Gorges Reservoir Area, and the overall accuracy was 94.53 %. The accuracy of the two layer hierarchical monitoring results indicated that the multi-scale monitoring method is feasible and reliable.

  19. Monitoring forest dynamics with multi-scale and time series imagery.

    PubMed

    Huang, Chunbo; Zhou, Zhixiang; Wang, Di; Dian, Yuanyong

    2016-05-01

    To learn the forest dynamics and evaluate the ecosystem services of forest effectively, a timely acquisition of spatial and quantitative information of forestland is very necessary. Here, a new method was proposed for mapping forest cover changes by combining multi-scale satellite remote-sensing imagery with time series data. Using time series Normalized Difference Vegetation Index products derived from the Moderate Resolution Imaging Spectroradiometer images (MODIS-NDVI) and Landsat Thematic Mapper/Enhanced Thematic Mapper Plus (TM/ETM+) images as data source, a hierarchy stepwise analysis from coarse scale to fine scale was developed for detecting the forest change area. At the coarse scale, MODIS-NDVI data with 1-km resolution were used to detect the changes in land cover types and a land cover change map was constructed using NDVI values at vegetation growing seasons. At the fine scale, based on the results at the coarse scale, Landsat TM/ETM+ data with 30-m resolution were used to precisely detect the forest change location and forest change trend by analyzing time series forest vegetation indices (IFZ). The method was tested using the data for Hubei Province, China. The MODIS-NDVI data from 2001 to 2012 were used to detect the land cover changes, and the overall accuracy was 94.02 % at the coarse scale. At the fine scale, the available TM/ETM+ images at vegetation growing seasons between 2001 and 2012 were used to locate and verify forest changes in the Three Gorges Reservoir Area, and the overall accuracy was 94.53 %. The accuracy of the two layer hierarchical monitoring results indicated that the multi-scale monitoring method is feasible and reliable. PMID:27056478

  20. Sulphur-oxidizing and sulphate-reducing communities in Brazilian mangrove sediments.

    PubMed

    Varon-Lopez, Maryeimy; Dias, Armando Cavalcante Franco; Fasanella, Cristiane Cipolla; Durrer, Ademir; Melo, Itamar Soares; Kuramae, Eiko Eurya; Andreote, Fernando Dini

    2014-03-01

    Mangrove soils are anaerobic environments rich in sulphate and organic matter. Although the sulphur cycle is one of the major actors in this ecosystem, little is known regarding the sulphur bacteria communities in mangrove soils. We investigated the abundance, composition and diversity of sulphur-oxidizing (SOB) and sulphate-reducing (SRB) bacteria in sediments from three Brazilian mangrove communities: two contaminated, one with oil (OilMgv) and one with urban waste and sludge (AntMgv), and one pristine (PrsMgv). The community structures were assessed using quantitative real-time polymerase chain reaction (qPCR), polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and clone libraries, using genes for the enzymes adenosine-5'-phosphosulphate reductase (aprA) and sulphite reductase (Dsr) (dsrB). The abundance for qPCR showed the ratio dsrB/aprA to be variable among mangroves and higher according to the gradient observed for oil contamination in the OilMgv. The PCR-DGGE patterns analysed by Nonmetric Multidimensional Scaling revealed differences among the structures of the three mangrove communities. The clone libraries showed that Betaproteobacteria, Gammaproteobacteria and Deltaproteobacteria were the most abundant groups associated with sulphur cycling in mangrove sediments. We conclude that the microbial SOB and SRB communities in mangrove soils are different in each mangrove forest and that such microbial communities could possibly be used as a proxy for contamination in mangrove forests.

  1. Global characterization and monitoring of forest cover using Landsat data: opportunities and challanges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The compilation of global Landsat data-sets and the ever-lowering costs of computing now make it feasible to monitor the Earth’s land cover at Landsat resolutions of 30 m. In this article, we describe the methods to create global products of forest cover and cover change at Landsat resolutions. Neve...

  2. Monitoring Network Confirms Land Use Change is a Substantial Component of the Forest Carbon Sink in the eastern United States

    PubMed Central

    Woodall, C. W.; Walters, B. F.; Coulston, J. W.; D’Amato, A. W.; Domke, G. M.; Russell, M. B.; Sowers, P. A.

    2015-01-01

    Quantifying forest carbon (C) stocks and stock change within a matrix of land use (LU) and LU change is a central component of large-scale forest C monitoring and reporting practices prescribed by the Intergovernmental Panel on Climate Change (IPCC). Using a region–wide, repeated forest inventory, forest C stocks and stock change by pool were examined by LU categories. In eastern US forests, LU change is a substantial component of C sink strength (~37% of forest sink strength) only secondary to that of C accumulation in forests remaining forest where their comingling with other LUs does not substantially reduce sink strength. The strongest sinks of forest C were study areas not completely dominated by forests, even when there was some loss of forest to agriculture/settlement/other LUs. Long-term LU planning exercises and policy development that seeks to maintain and/or enhance regional C sinks should explicitly recognize the importance of maximizing non-forest to forest LU changes and not overlook management and conservation of forests located in landscapes not currently dominated by forests. PMID:26639409

  3. Monitoring Network Confirms Land Use Change is a Substantial Component of the Forest Carbon Sink in the eastern United States

    NASA Astrophysics Data System (ADS)

    Woodall, C. W.; Walters, B. F.; Coulston, J. W.; D'Amato, A. W.; Domke, G. M.; Russell, M. B.; Sowers, P. A.

    2015-12-01

    Quantifying forest carbon (C) stocks and stock change within a matrix of land use (LU) and LU change is a central component of large-scale forest C monitoring and reporting practices prescribed by the Intergovernmental Panel on Climate Change (IPCC). Using a region-wide, repeated forest inventory, forest C stocks and stock change by pool were examined by LU categories. In eastern US forests, LU change is a substantial component of C sink strength (~37% of forest sink strength) only secondary to that of C accumulation in forests remaining forest where their comingling with other LUs does not substantially reduce sink strength. The strongest sinks of forest C were study areas not completely dominated by forests, even when there was some loss of forest to agriculture/settlement/other LUs. Long-term LU planning exercises and policy development that seeks to maintain and/or enhance regional C sinks should explicitly recognize the importance of maximizing non-forest to forest LU changes and not overlook management and conservation of forests located in landscapes not currently dominated by forests.

  4. Sediment CO2 efflux from cleared and intact temperate mangrove and tidal flat habitat

    NASA Astrophysics Data System (ADS)

    Bulmer, Richard; Lundquist, Carolyn; Schwendenmann, Luitgard

    2015-04-01

    Temperate mangroves in Southern Australia and New Zealand have been increasing in extent over the past 50 years, whereas tropical mangroves have declined by 30-50% over a similar time frame to support development of aquaculture, land development and timber production. Tropical mangroves are understood to be an important carbon sink and carbon emissions following clearance are estimated to be significant; comparable or greater than clearance of many terrestrial forest systems. As temperate mangrove clearance is proposed and has already occurred at some locations, it is important to determine potential carbon emissions from temperate mangroves, as well as exploring the factors which may influence emission rates. Here, we investigated the impact of temperate mangrove clearance on CO2 efflux from the sediment to the atmosphere along with a range of other biotic and abiotic factors. Higher CO2 efflux rates were observed within cleared (1.34

  5. Importance of different carbon sources for macroinvertebrates and fishes of an interlinked mangrove-mudflat ecosystem (Tanzania)

    NASA Astrophysics Data System (ADS)

    Kruitwagen, G.; Nagelkerken, I.; Lugendo, B. R.; Mgaya, Y. D.; Bonga, S. E. Wendelaar

    2010-08-01

    Mangroves function as important shelter and feeding habitats for marine fauna, but the degree to which mangrove-derived carbon contributes to local food webs has long been debated. In this study, stable isotope analysis was used as a technique to elucidate the role of mangrove carbon in the diets of the macroinvertebrate and fish fauna of an intertidal fringing mangrove forest and adjacent intertidal/subtidal mudflats in a macrotidal Tanzanian estuary. The expectation was that sessile species and those with low motility depend to a larger extent on local carbon sources than highly motile species. A clear distinction in δ 13C was present between primary producers from mangrove and mudflat habitats. Macroinvertebrates revealed a gradient in their δ 13C where Sesarma crabs were the only species that directly utilised mangrove carbon by feeding on mangrove leaves/detritus. Uca crabs and the gastropod Littoraria scabra showed a higher dependence on microphytobenthos from the mangrove substratum. Among the fish fauna, the amphibious mudskipper was the only species to which the mangroves were accessible during low tide. Consequently this was the only fish species for which it was clear that it fed in the mangrove habitat, most commonly on mangrove-associated Uca crabs. All other species of sessile as well as motile macroinvertebrates and fish from the mangrove and mudflat habitat showed a high degree of utilisation of mudflat carbon. Overall, mangrove carbon thus contributed little to the mangrove and mudflat food webs, despite the high tidal amplitude and the resulting potential for exchange of carbon and fauna in the estuary studied here. Utilisation of mangrove carbon appears to depend more on the ecology of the species in consideration (e.g., species-specific use of zones within the mangrove habitat) than on their potential motility or tolerance to exposure during low tide.

  6. Mangroves enhance the biomass of coral reef fish communities in the Caribbean.

    PubMed

    Mumby, Peter J; Edwards, Alasdair J; Arias-González, J Ernesto; Lindeman, Kenyon C; Blackwell, Paul G; Gall, Angela; Gorczynska, Malgosia I; Harborne, Alastair R; Pescod, Claire L; Renken, Henk; Wabnitz, Colette C C; Llewellyn, Ghislane

    2004-02-01

    Mangrove forests are one of the world's most threatened tropical ecosystems with global loss exceeding 35% (ref. 1). Juvenile coral reef fish often inhabit mangroves, but the importance of these nurseries to reef fish population dynamics has not been quantified. Indeed, mangroves might be expected to have negligible influence on reef fish communities: juvenile fish can inhabit alternative habitats and fish populations may be regulated by other limiting factors such as larval supply or fishing. Here we show that mangroves are unexpectedly important, serving as an intermediate nursery habitat that may increase the survivorship of young fish. Mangroves in the Caribbean strongly influence the community structure of fish on neighbouring coral reefs. In addition, the biomass of several commercially important species is more than doubled when adult habitat is connected to mangroves. The largest herbivorous fish in the Atlantic, Scarus guacamaia, has a functional dependency on mangroves and has suffered local extinction after mangrove removal. Current rates of mangrove deforestation are likely to have severe deleterious consequences for the ecosystem function, fisheries productivity and resilience of reefs. Conservation efforts should protect connected corridors of mangroves, seagrass beds and coral reefs. PMID:14765193

  7. Comparing Aedes vigilax Eggshell Densities in Saltmarsh and Mangrove Systems with Implications for Management.

    PubMed

    Dale, Pat; Knight, Jon; Griffin, Lachlan

    2014-01-01

    Aedes vigilax (Skuse), a nuisance and disease vector, is prolific in intertidal wetlands in Australia. Aedine mosquitoes oviposit directly onto substrate. The eggshells are relatively stable spatially and temporally, providing an estimate of mosquito larval production. The aims of the research were to compare, at a general level, oviposition in mangroves and saltmarshes, and to compare oviposition between different habitats within mangroves and saltmarshes. The results indicated that there were no significant differences between production in mangrove and saltmarsh overall. However, within each system there were significant differences between habitat classes, with mangrove hummocks being the most productive. All classes, except for fringing mangrove forests, produced sufficient densities of eggshells (>0.05/cc) to warrant concern. While mosquito production in mangroves is known, the significantly higher production rates in the mangrove hummock habitats had not been demonstrated. This warrants improved management strategies that both specifically target these parts of mangrove systems and, secondly, addresses the longer-term potential for mangrove hummock habitats developing in the future; such as, in response to sea level rise and mangrove encroachment into saltmarsh. A strategy to increase tidal flushing within the systems would improve water quality and mitigate adverse impacts while providing a source reduction outcome.

  8. Chemical ecology of red mangroves, Rhizophora mangle, in the Hawaiian Islands

    USGS Publications Warehouse

    Fry, Brian; Cormier, Nicole

    2011-01-01

    The coastal red mangrove, Rhizophora mangle L., was introduced to the Hawaiian Islands from Florida 100 yr ago and has spread to cover many shallow intertidal shorelines that once were unvegetated mudflats. We used a field survey approach to test whether mangroves at the land-ocean interface could indicate watershed inputs, especially whether measurements of leaf chemistry could identify coasts with high nutrient inputs and high mangrove productivities. During 2001-2002, we sampled mangroves on dry leeward coasts of southern Moloka'i and O'ahu for 14 leaf variables including stable carbon and nitrogen isotopes (delta13C, delta15N), macronutrients (C, N, P), trace elements (B, Mn, Fe, Cu, Zn), and cations (Na, Mg, K, Ca). A new modeling approach using leaf Na, N, P, and delta13C indicated two times higher productivity for mangroves in urban versus rural settings, with rural mangroves more limited by low N and P nutrients and high-nutrient urban mangroves more limited by freshwater inputs and salt stress. Leaf chemistry also helped identify other aspects of mangrove dynamics: especially leaf delta15N values helped identify groundwater N inputs, and a combination of strongly correlated variables (C, N, P, B, Cu, Mg, K, Ca) tracked the mangrove growth response to nutrient loading. Overall, the chemical marker approach is an efficient way to survey watershed forcing of mangrove forest dynamics.

  9. Mangroves enhance the biomass of coral reef fish communities in the Caribbean

    NASA Astrophysics Data System (ADS)

    Mumby, Peter J.; Edwards, Alasdair J.; Ernesto Arias-González, J.; Lindeman, Kenyon C.; Blackwell, Paul G.; Gall, Angela; Gorczynska, Malgosia I.; Harborne, Alastair R.; Pescod, Claire L.; Renken, Henk; C. C. Wabnitz, Colette; Llewellyn, Ghislane

    2004-02-01

    Mangrove forests are one of the world's most threatened tropical ecosystems with global loss exceeding 35% (ref. 1). Juvenile coral reef fish often inhabit mangroves, but the importance of these nurseries to reef fish population dynamics has not been quantified. Indeed, mangroves might be expected to have negligible influence on reef fish communities: juvenile fish can inhabit alternative habitats and fish populations may be regulated by other limiting factors such as larval supply or fishing. Here we show that mangroves are unexpectedly important, serving as an intermediate nursery habitat that may increase the survivorship of young fish. Mangroves in the Caribbean strongly influence the community structure of fish on neighbouring coral reefs. In addition, the biomass of several commercially important species is more than doubled when adult habitat is connected to mangroves. The largest herbivorous fish in the Atlantic, Scarus guacamaia, has a functional dependency on mangroves and has suffered local extinction after mangrove removal. Current rates of mangrove deforestation are likely to have severe deleterious consequences for the ecosystem function, fisheries productivity and resilience of reefs. Conservation efforts should protect connected corridors of mangroves, seagrass beds and coral reefs.

  10. Mangroves enhance the biomass of coral reef fish communities in the Caribbean.

    PubMed

    Mumby, Peter J; Edwards, Alasdair J; Arias-González, J Ernesto; Lindeman, Kenyon C; Blackwell, Paul G; Gall, Angela; Gorczynska, Malgosia I; Harborne, Alastair R; Pescod, Claire L; Renken, Henk; Wabnitz, Colette C C; Llewellyn, Ghislane

    2004-02-01

    Mangrove forests are one of the world's most threatened tropical ecosystems with global loss exceeding 35% (ref. 1). Juvenile coral reef fish often inhabit mangroves, but the importance of these nurseries to reef fish population dynamics has not been quantified. Indeed, mangroves might be expected to have negligible influence on reef fish communities: juvenile fish can inhabit alternative habitats and fish populations may be regulated by other limiting factors such as larval supply or fishing. Here we show that mangroves are unexpectedly important, serving as an intermediate nursery habitat that may increase the survivorship of young fish. Mangroves in the Caribbean strongly influence the community structure of fish on neighbouring coral reefs. In addition, the biomass of several commercially important species is more than doubled when adult habitat is connected to mangroves. The largest herbivorous fish in the Atlantic, Scarus guacamaia, has a functional dependency on mangroves and has suffered local extinction after mangrove removal. Current rates of mangrove deforestation are likely to have severe deleterious consequences for the ecosystem function, fisheries productivity and resilience of reefs. Conservation efforts should protect connected corridors of mangroves, seagrass beds and coral reefs.

  11. Painting the world REDD: addressing scientific barriers to monitoring emissions from tropical forests

    NASA Astrophysics Data System (ADS)

    Asner, Gregory P.

    2011-06-01

    In December 2010, parties to the United Nations Framework Convention on Climate Change (UNFCCC) agreed to encourage reductions in greenhouse gas emissions from forest losses with the financial support of developed countries. This important international agreement followed about seven years of effort among governments, non-governmental organizations (NGO) and the scientific community, and is called REDD+, the program for Reducing Emissions from Deforestation and Forest Degradation. REDD+ could achieve its potential to slow emissions from deforestation and forest degradation either as a new market option to offset emissions from developed nations, or as a mitigation option for developing countries themselves. Aside from representing an important step towards reducing greenhouse gas emissions, a growing list of potential co-benefits to REDD+ include improved forestry practices, forest restoration, sustainable development, and biodiversity protection. Indeed the agreement is heralded as a win-win for climate change mitigation and tropical forest conservation, and it could end up contributing to a global economy based on carbon and ecosystem services. That's good news, and some governments are now working to become 'REDD ready' in preparation for the forthcoming international program. This is important because, according to the agreements made by governments in the UNFCCC, developing countries which voluntarily decide to take part in REDD+ must establish their own national forest monitoring system to report changes in emissions from forests (UNFCCC 2009). But as of today, no developing country has implemented a system for monitoring, reporting and verifying (MRV) emission reductions for REDD+. Of course, it is all still very new, but many REDD-type projects have been underway for years now (Parker et al 2008), and many MRV practitioners involved in those projects are the same people being asked to help with government-led, national MRV programs. Yet going from the

  12. Preliminary work of mangrove ecosystem carbon stock mapping in small island using remote sensing: above and below ground carbon stock mapping on medium resolution satellite image

    NASA Astrophysics Data System (ADS)

    Wicaksono, Pramaditya; Danoedoro, Projo; Hartono, Hartono; Nehren, Udo; Ribbe, Lars

    2011-11-01

    Mangrove forest is an important ecosystem located in coastal area that provides various important ecological and economical services. One of the services provided by mangrove forest is the ability to act as carbon sink by sequestering CO2 from atmosphere through photosynthesis and carbon burial on the sediment. The carbon buried on mangrove sediment may persist for millennia before return to the atmosphere, and thus act as an effective long-term carbon sink. Therefore, it is important to understand the distribution of carbon stored within mangrove forest in a spatial and temporal context. In this paper, an effort to map carbon stocks in mangrove forest is presented using remote sensing technology to overcome the handicap encountered by field survey. In mangrove carbon stock mapping, the use of medium spatial resolution Landsat 7 ETM+ is emphasized. Landsat 7 ETM+ images are relatively cheap, widely available and have large area coverage, and thus provide a cost and time effective way of mapping mangrove carbon stocks. Using field data, two image processing techniques namely Vegetation Index and Linear Spectral Unmixing (LSU) were evaluated to find the best method to explain the variation in mangrove carbon stocks using remote sensing data. In addition, we also tried to estimate mangrove carbon sequestration rate via multitemporal analysis. Finally, the technique which produces significantly better result was used to produce a map of mangrove forest carbon stocks, which is spatially extensive and temporally repetitive.

  13. Ecosystem development after mangrove wetland creation: plant-soil change across a 20-year chronosequence

    USGS Publications Warehouse

    Osland, Michael J.; Spivak, Amanda C.; Nestlerode, Janet A.; Lessmann, Jeannine M.; Almario, Alejandro E.; Heitmuller, Paul T.; Russell, Marc J.; Krauss, Ken W.; Alvarez, Federico; Dantin, Darrin D.; Harvey, James E.; From, Andrew S.; Cormier, Nicole; Stagg, Camille L.

    2012-01-01

    Mangrove wetland restoration and creation efforts are increasingly proposed as mechanisms to compensate for mangrove wetland losses. However, ecosystem development and functional equivalence in restored and created mangrove wetlands are poorly understood. We compared a 20-year chronosequence of created tidal wetland sites in Tampa Bay, Florida (USA) to natural reference mangrove wetlands. Across the chronosequence, our sites represent the succession from salt marsh to mangrove forest communities. Our results identify important soil and plant structural differences between the created and natural reference wetland sites; however, they also depict a positive developmental trajectory for the created wetland sites that reflects tightly coupled plant-soil development. Because upland soils and/or dredge spoils were used to create the new mangrove habitats, the soils at younger created sites and at lower depths (10-30 cm) had higher bulk densities, higher sand content, lower soil organic matter (SOM), lower total carbon (TC), and lower total nitrogen (TN) than did natural reference wetland soils. However, in the upper soil l