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1

Mangrove Forests  

NSDL National Science Digital Library

Where the tropical ocean meets the sea, a peculiar kind of plant thrives in shallow, salty water. These mangrove plants are incredibly important for shoreline protection and baby fish habitats. In this video, Jonathan investigates life in mangroves by visiting both Caribbean and Pacific mangroves. Please see the accompanying study guide for educational objectives and discussion points.

Productions, Jonathan B.

2010-05-05

2

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

NASA Astrophysics Data System (ADS)

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 sample. Conversely, strong positive significant correlation coefficients were calculated between the cross-polarization HV backscatter and LAI when the dead mangrove stands were considered. Although fewer in comparison to the HH correlations, a number of VV backscatter based relationships with mangrove parameters were observed from the quad polarization mode and, to a lesser extent, with the one single VV polarization data. In addition to backscatter coefficients, stepwise multiple regression models of the mangrove biophysical parameter data were developed based on texture parameters derived from the grey level co-occurrence matrix (GLCM) of the ALOS data. A similar pattern to the backscatter relationships was observed for models based on the single polarization unfiltered data, with fairly strong coefficients of determination calculated for LAI and stem height when the dead stands were excluded. In contrast, similar coefficients of determination with biophysical parameters were observed for the dual and quad polarization multiple regression models when the dead stands were both included and excluded from the analyses. An estimated mangrove LAI map of the study area, derived from a multiple regression model of the quad polarization texture parameters, showed comparable spatial patterns of degradation to a map derived from higher spatial resolution optical satellite data.

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

2013-08-01

3

Sedimentation in Mangrove Forests  

Microsoft Academic Search

The tidal currents in mangrove forests are impeded by the friction caused by the high vegetation density. The tidal currents are also complex comprising eddies, jets and stagnation zones. The sediment particles carried in suspension into the forest during tidal inundation are cohesive, mainly clay and fine silt, and form large flocs. These flocs remain in suspension as a result

Keita Furukawa; Eric Wolanski

1996-01-01

4

A preliminary assessment of NigeriaSat-1 for sustainable mangrove forest monitoring  

Microsoft Academic Search

Mangroves constitute an area of great ecological importance and regular assessment and monitoring of this ecosystem is an integral part of environmental management plan. The difficulty of access for ground survey has often limited the frequency of assessment of mangroves and remote sensing methods therefore provide a veritable means of assessment. However, accessibility to remotely sensed data as well as

Ayobami T. Salami; Joseph Akinyede; Alfred de Gier

2010-01-01

5

Mangrove Afforestation Monitoring Using Remote Sensing.  

National Technical Information Service (NTIS)

An overview of the mangrove afforestation monitoring conducted by the SPARRSO (Bangladesh Space Research and Remote Sensing Organization) using satellite remote sensing data is presented. The first five year program of afforestation to construct forest pr...

A. K. M. F. Bhuiyan M. J. Islam

1993-01-01

6

A preliminary assessment of NigeriaSat-1 for sustainable mangrove forest monitoring  

NASA Astrophysics Data System (ADS)

Mangroves constitute an area of great ecological importance and regular assessment and monitoring of this ecosystem is an integral part of environmental management plan. The difficulty of access for ground survey has often limited the frequency of assessment of mangroves and remote sensing methods therefore provide a veritable means of assessment. However, accessibility to remotely sensed data as well as the cost have been major constraints for mangrove assessment in the developing countries. The launching of small satellites by some developing countries may therefore provide a solution to this problem. This paper is an attempt to evaluate the capability of NigeriaSat-1 which is one of the Disaster Management Constellation (DMC) small satellites for generation of baseline information on cover types and areal extents within the mangrove zone in Nigeria. This is important since cover information is always the first step for conservation and management. The study shows that the results obtained from NigeriaSat-1 have comparable accuracy with ASTER and Landsat ETM+. The findings documented in this paper could serve as a springboard for organized wetland management in Nigeria in particular and West Africa sub-region in general.

Salami, Ayobami T.; Akinyede, Joseph; de Gier, Alfred

7

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

USGS Publications Warehouse

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.

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

2007-01-01

8

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)

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.

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

2007-06-01

9

The Role of Mangrove Ecosystems: Mangrove Forest Types and Biomass.  

National Technical Information Service (NTIS)

Five physiognomic types of mangrove forests are identified on the basis of local topography, coastal position and relationship to terrestrial runoff and tidal flushing. Estimates of biomass, by compartment, are reported for an overwash forest, fringe fore...

S. C. Snedaker D. J. Pool

1973-01-01

10

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

NASA Technical Reports Server (NTRS)

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.

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

2014-01-01

11

Mathematical modelling of tidal currents in mangrove forests  

Microsoft Academic Search

The effects of mangrove forests on the flow structure in estuaries have been studied in this paper. An existing two-dimensional depth-integrated mathematical model has been refined to include both the effects of drag force induced by mangrove trees and the blockage effects on the mass fluxes through mangrove forests. To investigate the influence of mangrove trees on the flow structure

Y. Wu; Roger A. Falconer; J. Struve

2001-01-01

12

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

USGS Publications Warehouse

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.

Giri, C.; Muhlhausen, J.

2008-01-01

13

Mangrove Forest Distributions and Dynamics in Madagascar (1975-2005)  

PubMed Central

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%).

Giri, Chandra; Muhlhausen, Joseph

2008-01-01

14

Soil Respiration of Three Mangrove Forests on Sanibel Island, Florida  

NASA Astrophysics Data System (ADS)

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 ?mol 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 ?mol 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 effluxes are higher than reported in previous studies for mangrove ecosystems.

Cartwright, F.; Bovard, B. D.

2011-12-01

15

Threat of heavy metal contamination in eight mangrove plants from the Futian mangrove forest, China.  

PubMed

Mangrove plants play an important role in heavy metal maintenance in a mangrove ecosystem. To evaluate the characteristics of heavy metal contamination in the Futian mangrove forest, Shenzhen, China, eight heavy metals in mangrove sediments and plants were monitored, including essential elements such as Cu and Zn, and non-essential elements such as Cr, Ni, As, Cd, Pb and Hg. The results showed that the heavy metals exhibited the following scheme: Zn > As > Cu ? Cr > Pb > Ni > Cd ? Hg in sediment cores, among which Cd, As, Pb and Hg contents were nearly ten times higher than the background values. There was no significant difference in metal maintenance capability between native and exotic species. In mangrove plants' leaves and stems, concentrations of Cu, Zn and As were higher than other heavy metals. The low bioconcentration factors for most heavy metals, except for Cr, implied the limited ability of heavy metal accumulation by the plants. Mangrove plants seem to develop some degree of tolerance to Cr. The factor analysis implies that anthropogenic influences have altered metal mobility and bioavailability. PMID:24085617

He, Bei; Li, Ruili; Chai, Minwei; Qiu, Guoyu

2014-06-01

16

Seasonal evapotranspiration patterns in mangrove forests  

NASA Astrophysics Data System (ADS)

and seasonal controls on water vapor fluxes were investigated in a subtropical mangrove forest in Everglades National Park, Florida. Energy partitioning between sensible and latent heat fluxes was highly variable during the 2004-2005 study period. During the dry season, the mangrove forest behaved akin to a semiarid ecosystem as most of the available energy was partitioned into sensible heat, which gave Bowen ratio values exceeding 1.0 and minimum latent heat fluxes of 5 MJ d-1. In contrast, during the wet season the mangrove forest acted as a well-watered, broadleaved deciduous forest, with Bowen ratio values of 0.25 and latent heat fluxes reaching 18 MJ d-1. During the dry season, high salinity levels (> 30 parts per thousand, ppt) caused evapotranspiration to decline and correspondingly resulted in reduced canopy conductance. From multiple linear regression, daily average canopy conductance to water vapor declined with increasing salinity, vapor pressure deficit, and daily sums of solar irradiance but increased with air temperature and friction velocity. Using these relationships, appropriately modified Penman-Monteith and Priestley-Taylor models reliably reproduced seasonal trends in daily evapotranspiration. Such numerical models, using site-specific parameters, are crucial for constructing seasonal water budgets, constraining hydrological models, and driving regional climate models over mangrove forests.

Barr, Jordan G.; DeLonge, Marcia S.; Fuentes, Jose D.

2014-04-01

17

Interpretation of Polarimetric Radar Signatures of Mangrove Forests  

Microsoft Academic Search

Polarimetric AIRSAR data acquired over a variety of mangrove forests are analyzed with the assistance of a three-layer radiative transfer model. The necessary input parameters to the model come from detailed ground measurements performed in 12 mangrove stands that are representative of the different successional stages of the mangrove forest dynamics. On the whole, P-band provides the most pronounced polarimetric

C. Proisy; E. Mougin; F. Fromard; M. A. Karam

2000-01-01

18

The current status of world protection for mangrove forest  

NASA Astrophysics Data System (ADS)

Mangrove forests occur extensively in the tropic areas rich in wildlife and other nonforestry resources and provide a wide array of raw materials for livelihood and production processes and have been a major source of income generation and subsistence for the local people. Exploitation of timber, fuel wood, poles, industrial raw material, and many other non-wood produets from the mangrove forests give rise to large scale economic activity and income generation. At present, mangrove forests are facing great peril. Reckless exploitation and swampland reclamation result in their gradual degradation. This article deals with the world’s mangrove forest resources and their benefit to people; describes the current status, points out the main causes of the destruction of these forests, presents proposals for protecting mangrove forests, and discusses international cooperation in protecting the world’s mangrove forests.

Zhengyun, Zhang; Zhixian, Su; Qiaoying, Zhang; Aiying, Shen

2003-09-01

19

Coastal mangrove forests mitigated tsunami  

Microsoft Academic Search

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

Kandasamy Kathiresan; Narayanasamy Rajendran

2005-01-01

20

Carbon Cycling and Storage in Mangrove Forests  

NASA Astrophysics Data System (ADS)

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.

Alongi, Daniel M.

2014-01-01

21

Ecological engineering for successful management and restoration of mangrove forests  

Microsoft Academic Search

Abstract Great potential exists to reverse the loss of mangrove,forests worldwide,through the application of basic principles of ecological restoration using ecological engineering approaches, including careful cost evaluations prior to design and construction. Previous documented attempts to restore mangroves, where successful, have largely concentrated on creation of plantations of mangroves consisting of just a few species, and targeted for harvesting as

Roy R. Lewis III

22

Ecological engineering for successful management and restoration of mangrove forests  

Microsoft Academic Search

Great potential exists to reverse the loss of mangrove forests worldwide through the application of basic principles of ecological restoration using ecological engineering approaches, including careful cost evaluations prior to design and construction. Previous documented attempts to restore mangroves, where successful, have largely concentrated on creation of plantations of mangroves consisting of just a few species, and targeted for harvesting

Roy R. Lewis

2005-01-01

23

Ethnobiology, socio-economics and management of mangrove forests: A review  

Microsoft Academic Search

There is growing research interest in the ethnobiology, socio-economics and management of mangrove forests. Coastal residents who use mangroves and their resources may have considerable botanical and ecological knowledgeable about these forests. A wide variety of forest products are harvested in mangroves, especially wood for fuel and construction, tannins and medicines. Although there are exceptions, mangrove forest products are typically

Bradley B. Walters; Patrik Rönnbäck; John M. Kovacs; Beatrice Crona; Syed Ainul Hussain; Ruchi Badola; Jurgenne H. Primavera; Edward Barbier; Farid Dahdouh-Guebas

2008-01-01

24

Predicting Future Mangrove Forest Migration in the Everglades Under Rising Sea Level  

USGS Publications Warehouse

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).

Doyle, Thomas W.

2003-01-01

25

Restoration of biogeochemical function in mangrove forests  

USGS Publications Warehouse

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-specific as well as regional or local differences in hydrology and concomitant factors such as salinity and soil waterlogging will have a strong influence over the outcome of restoration projects.

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

2000-01-01

26

Present state and future of the world's mangrove forests  

Microsoft Academic Search

SUMMARY Mangroves, the only woody halophytes living at the confluence of land and sea, have been heavily used traditionally for food, timber, fuel and medicine, and presently occupy about 181 000 km 2 of tropical and subtropical coastline. Over the past 50 years, approxi- mately one-third of the world's mangrove forests have been lost, but most data show very variable

Daniel M. Alongi

2002-01-01

27

Downed wood in Micronesian mangrove forests  

USGS Publications Warehouse

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.

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

2000-01-01

28

Multifrequency and multipolarization radar backscattering from mangrove forests  

Microsoft Academic Search

The authors examine the dependence between multifrequency\\/multipolarization synthetic aperture radar (SAR) data and mangrove forest parameters. AIRSAR data at P-, L-, and C-band were acquired over French Guiana in June 1993. Structural parameters, namely, tree height, tree diameter at breast height (DBH), tree density, basal area, and total above-ground biomass were estimated in 12 stands representative of different mangrove forest

E. Mougin; C. Proisy; G. Marty; F. Fromard; H. Puig; J. L. Betoulle; J. P. Rudant

1999-01-01

29

Degradation of mangrove forests in South Sulawesi, Indonesia  

Microsoft Academic Search

In South Sulawesi forests contain a large variety of genera and species of plants. These forests are important as sources of timber, fuelwood, food and many other minor products. The major concern over this important coastal resource is its increasing rate of exploitation. Prior to 1965 it was estimated that there were at least 110 000 hectares of mangrove forests

Baharuddin Nurkin; N. Marshall; D. J. Macintosh

1994-01-01

30

National Level Assessment of Mangrove Forest Cover in Pakistan  

NASA Astrophysics Data System (ADS)

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. GIS and Remote Sensing based technologies and methods are in use to map forest cover since the last two decades in Pakistan. The national level forest cover studies based upon satellite images include, Forestry Sector Master Plan (FSMP) and National Forest & Range Resources Assessment Study (NFRRAS). In FSMP, the mangrove forest extent was visually determined from Landsat images of 1988 - 1991, and was estimated to be 155,369 ha; whereas, in NFRRAS, Landsat images of 1997 - 2001 were automated processed and the mangroves areas was estimated to be 158,000 ha. To our knowledge, a comprehensive assessment of current mangroves cover of Pakistan has not been made over the last decade, although the mangroves ecosystems have become the focus of intention in context of recent climate change scenarios. This study was conducted to support the informed decision making for sustainable development in coastal areas of Pakistan by providing up-todate mangroves forest cover assessment of Pakistan. Various types of Earth Observation satellite images and processing methods have been tested in relation to mangroves mapping. Most of the studies have applied classical pixel - based approached, there are a few studies which used object - based methods of image analysis to map the mangroves ecosystems. Object - based methods have the advantage of incorporating spatial neighbourhood properties and hierarchical structures into the classification process to produce more accurate surface patterns recognition compared with classical pixel - based approaches. In this research, we applied multi-scale hierarchical approach of object-based methods of image analysis to ALOS - AVNIR-2 images of the year 2008-09 to map the land cover in the mangroves ecosystems of Pakistan. Considering the tide height and phonological effects of vegetation, particularly the algal mats, these data sets were meticulously chosen. Incorporation of multi-scale hierarchical structures made it easy to effectively discriminate among the land cover classes, particularly the mudflats from sparse mangroves, at their r

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

2011-09-01

31

Mapping the Philippines' mangrove forests using Landsat imagery  

USGS Publications Warehouse

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.

Long, J. B.; Giri, C.

2011-01-01

32

Cage experiments in an East African mangrove forest: a synthesis  

NASA Astrophysics Data System (ADS)

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.

Schrijvers, J.; Vincx, M.

1997-12-01

33

Mapping the Philippines' mangrove forests using Landsat imagery.  

PubMed

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

Long, Jordan B; Giri, Chandra

2011-01-01

34

Distribution and dynamics of mangrove forests of South Asia  

USGS Publications Warehouse

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 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.

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

2014-01-01

35

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

PubMed

Given the alarming global rates of mangrove forest loss it is important that resource managers have access to updated information regarding both the extent and condition of their mangrove forests. Mexican mangroves in particular have been identified as experiencing an exceptional high annual rate of loss. However, conflicting studies, using remote sensing techniques, of the current state of many of these forests may be hindering all efforts to conserve and manage what remains. Focusing on one such system, the Teacapán-Agua Brava-Las Haciendas estuarine-mangrove complex of the Mexican Pacific, an attempt was made to develop a rapid method of mapping the current condition of the mangroves based on estimated LAI. Specifically, using an AccuPAR LP-80 Ceptometer, 300 indirect in situ LAI measurements were taken at various sites within the black mangrove (Avicennia germinans) dominated forests of the northern section of this system. From this sample, 225 measurements were then used to develop linear regression models based on their relationship with corresponding values derived from QuickBird very high resolution optical satellite data. Specifically, regression analyses of the in situ LAI with both the normalized difference vegetation index (NDVI) and the simple ration (SR) vegetation index revealed significant positive relationships [LAI versus NDVI (R (2) = 0.63); LAI versus SR (R (2) = 0.68)]. Moreover, using the remaining sample, further examination of standard errors and of an F test of the residual variances indicated little difference between the two models. Based on the NDVI model, a map of estimated mangrove LAI was then created. Excluding the dead mangrove areas (i.e. LAI = 0), which represented 40% of the total 30.4 km(2) of mangrove area identified in the scene, a mean estimated LAI value of 2.71 was recorded. By grouping the healthy fringe mangrove with the healthy riverine mangrove and by grouping the dwarf mangrove together with the poor condition 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

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

2009-10-01

36

Organic carbon inventories in natural and restored Ecuadorian mangrove forests  

PubMed Central

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.

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

2014-01-01

37

Organic carbon inventories in natural and restored Ecuadorian mangrove forests.  

PubMed

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

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

2014-01-01

38

The integration of spectral analyses of Landsat ETM+ with the DEM data for mapping mangrove forests  

Microsoft Academic Search

This study aims to develop an efficient method to extract mangrove forests at a regional scale using remote sensing data and Geographic Information Systems (GIS) technique. A regional mangrove forests mapping method was developed based on the spectral characteristics and the topographic existence condition of mangrove forests. Landsat Enhanced Thematic Mapper plus (ETM+) and digital elevation model (DEM) were used

Bayan Alsaaideh; Ahmad Al-Hanbali; Ryutaro Tateishi; Hoan Nguyen Thanh

2011-01-01

39

Socio-institutional dynamics and the political ecology of mangrove forest conservation in Central Sulawesi, Indonesia  

Microsoft Academic Search

Mangrove forests provide a range of ecological and socio-economic benefits in coastal zones throughout the world's tropical regions. Yet the conversion of mangrove forest, due in particular to aquaculture development, is occurring at a dramatic rate. Drawing on insights and concepts offered by political ecology and complex systems, processes of mangrove forest conversion and aquaculture development in the coastal zone

Derek Armitage

2002-01-01

40

Leaf choice by crustaceans in a mangrove forest in Queensland  

Microsoft Academic Search

The feeding behaviour of leaf eating crustaceans feeding on leaves shed by Avicennia marina, Bruguiera gymnorhiza and Rhizophora stylosa in the mangrove forest at Myora Springs, Queensland, Australia was studied between 1980 and 1984. Individual Sesarma erythrodactyla (carapace >9 mm long), one of the most abundant species of crabs in the forest, processed approximately half a leaf from any of

J. Camilleri

1989-01-01

41

Mangrove forest recovery in the Everglades following Hurricane Wilma  

USGS Publications Warehouse

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.

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

2009-01-01

42

Soil Respiration and Belowground Carbon Allocation in Mangrove Forests  

Microsoft Academic Search

Mangrove forests cover large areas of tropical and subtropical coastlines. They provide a wide range of ecosystem services\\u000a that includes carbon storage in above- and below ground biomass and in soils. Carbon dioxide (CO2) emissions from soil, or soil respiration is important in the global carbon budget and is sensitive to increasing global\\u000a temperature. To understand the magnitude of mangrove

Catherine E. Lovelock

2008-01-01

43

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

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

44

Surface wave propagation in mangrove forests  

Microsoft Academic Search

Mangroves are a special form of vegetation as they exist at the boundary of terrestrial and marine environment. They have a special role in supporting fisheries and in the stabilizing the tropical coastal zones. Biochemical and trophodynamic processes in the mangroves are strongly linked to water movement, due to tides and waves. In this paper we present the theoretical attempt

S. R. Massel; K. Furukawa; R. M. Brinkman

1999-01-01

45

Mangrove Forest and Soil Development on a Rapidly Accreting Shore in New Zealand  

Microsoft Academic Search

Mangrove forests are rapidly expanding their distribution in New Zealand, which is at the southern limit of their range. We\\u000a investigated how these expanding mangrove forests develop through time. We assessed patterns in forest structure and function\\u000a at the Firth of Thames, which is a rapidly accreting mangrove site in New Zealand where 1 km of mangrove of Avicennia marina has

Catherine E. Lovelock; Brian K. Sorrell; Nicole Hancock; Quan Hua; Andrew Swales

2010-01-01

46

Remote Characterization of Biomass Measurements: Case Study of Mangrove Forests  

NASA Technical Reports Server (NTRS)

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, this book chapter has 3 main objectives: a) To describe in detail the field methodologies used to derive accurate estimates of biomass in mangrove forests b) To explain how mangrove forest biomass can be measured using several remote sensing techniques and datasets c) To give a detailed explanation of the measurement challenges and errors that arise in each estimate of forest biomass

Fatoyinbo, Temilola E.

2010-01-01

47

Mangrove forest structure and productivity in the Fly River estuary, Papua New Guinea  

Microsoft Academic Search

In April, July and August 1989 and February 1990, the delta region of the Fly River was surveyed to establish the aerial extent of mangrove forests, their species composition, tree densities and basal areas, and potential net primary production. Mangrove forests cover 87 400 ha, mainly on islands within the delta. Twentynine mangrove plant species were recorded, but there were

A. I. Robertson; P. A. Daniel; P. Dixon

1991-01-01

48

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

Microsoft Academic Search

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

Daniel M. Alongi

2008-01-01

49

A baseline study of the diversity and community ecology of crab and molluscan macrofauna in the Sematan mangrove forest, Sarawak, Malaysia  

Microsoft Academic Search

Baseline ecological studies of pristine mangroves are important for monitoring, management and conservation of mangrove ecosystems. Diversity, density, biomass and community structure of crab and molluscan macrofauna were studied in a near-pristine mangrove forest in Sematan, Sarawak. In each of the nine 100-m 2 plots, six 15-min catching periods were used to collect crabs and three 1-m 2 quadrats were

Elizabeth C. Ashton; Donald J. Macintosh; Peter J. Hogarth

2003-01-01

50

Woody Debris in the mangrove forests of South Florida  

USGS Publications Warehouse

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.

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

2005-01-01

51

Carbon stocks and potential carbon storage in the mangrove forests of China.  

PubMed

Mangrove forests provide important ecosystem services, and play important roles in terrestrial and oceanic carbon (C) cycling. Although the C stocks or storage in terrestrial ecosystems in China have been frequently assessed, the C stocks in mangrove forests have often been overlooked. In this study, we estimated the C stocks and the potential C stocks in China's mangrove forests by combining our own field data with data from the National Mangrove Resource Inventory Report and from other published literature. The results indicate that mangrove forests in China store about 6.91 ± 0.57 Tg C, of which 81.74% is in the top 1 m soil, 18.12% in the biomass of mangrove trees, and 0.08% in the ground layer (i.e. mangrove litter and seedlings). The potential C stocks are as high as 28.81 ± 4.16 Tg C. On average, mangrove forests in China contain 355.25 ± 82.19 Mg C ha(-1), which is consistent with the global average of mangrove C density at similar latitudes, but higher than the average C density in terrestrial forests in China. Our results suggest that C storage in mangroves can be increased by selecting high C-density species for afforestation and stand improvement, and even more by increasing the mangrove area. The information gained in this study will facilitate policy decisions concerning the restoration of mangrove forests in China. PMID:24374165

Liu, Hongxiao; Ren, Hai; Hui, Dafeng; Wang, Wenqing; Liao, Baowen; Cao, Qingxian

2014-01-15

52

COASTAL ZONE STABILISATION, RESTORATION AND ENHANCEMENT THROUGH MANGROVE FOREST ESTABLISHMENT  

Microsoft Academic Search

Ill-planned construction, reclamation works and aquaculture projects were highlighted in the National Coastal Erosion Study (1984 - 1986) as the major cause of damage to the Malaysia coast. Pressures of these developments have threatened the existence of mangrove forest, the most productive ecosystems on earth. They are the natural protection against coastal erosion, the basic source of wood in timber

Nor Aslinda Awang; Khairol Azuan Adam; Shahrani Mamad

53

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

PubMed

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

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

2010-09-01

54

Remotely based monitoring of the mangroves over Penang Island, Malaysia  

NASA Astrophysics Data System (ADS)

Mangrove vegetations are normally present in river estuaries and along the coast where the land meets the sea. Remote sensing can be used to obtain mangrove distribution information. The objective of this study was to study the current condition of mangrove forest using remote sensing over Penang Island, Malaysia. An attempt has been made based on supervised Maximum Likelihood Classification (MLC), various land use and land cover classes have been mapped and classified. A red-green-blue (RGB) colour was used to display and quantify mangrove forest distribution using Thailand Earth Observation System (THEOS) satellite imagery. Reference data was based on ground truth. High accuracy of 91.7% was obtained in mapping of mangrove cover.

Beh, B. C.; Matjafri, M. Z.; Lim, H. S.

2010-10-01

55

MANGROVE FOREST COVER MAPPING IN PHANGNGA BAY, THAILAND; USING SPOT HRV AND JERS-1 DATA IN CONJUNCTION WITH GIS 1  

Microsoft Academic Search

Mangrove forest in Phangnga Bay, Southern Thailand were analyzed using SPOT XS and JERS-1 data. Particular emphasis was given to the applicability of remote sensing and GIS for discriminating mangrove and non-mangrove areas and also for the detail classification of mangrove forests based on species and density. Results show that mangrove and non-mangrove discrimination can be done with an extremely

Chandra Prasad Giri; Jean-Pierre Delsol

56

Soil characteristics and nutrient status in a Northern Australian mangrove forest  

Microsoft Academic Search

The results of a study of soil factors in relation to plant growth for a tropical mangrove forest in northern Australia are\\u000a presented and discussed. Basic soil properties are described briefly in terms of particle size distribution, bulk density\\u000a and total carbon, nitrogen and phosphorus. Soil redox potential, pH, salinity and extractable nitrogen and phosphorus were\\u000a monitored monthly over a

Kevin G. Boto; John T. Wellington

1984-01-01

57

Currents and Sediment Transport in Mangrove Forests  

Microsoft Academic Search

A field study of the tidal currents, cohesive sediment dynamics and transport of organic carbon in a highly vegetated mangrove swamp was carried out at Middle Creek, Cairns, Australia. The interaction of tidal currents and the vegetation generated jets, eddies and zones of stagnant waters which were numerically modelled. A high value of the Manning friction coefficient (n=0·1) was derived

K. Furukawa; E. Wolanski; H. Mueller

1997-01-01

58

Ecosystem-Level Carbon Stocks in Costa Rican Mangrove Forests  

NASA Astrophysics Data System (ADS)

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 represent 38 to 43% of the total ecosystem carbon stocks measured in the Indo-Pacific region, which are among the most carbon-rich ecosystems in the world. Overall, the mangrove forest in the Térraba-Sierpe National Wetland contain close to 8 Tg C, which represents approximately 40% of all carbon currently stored nationwide in mangrove stands. Although deforestation and forest degradation processes have been, for the most part, controlled in the country, available data suggest that between 1990 and 2012 Costa Rica lost almost 4000 ha (8 % of currently remaining area) of mangrove forests. This translates in historical emissions of 1.6 Tg C, which is equivalent to 1.3 times the greenhouse gas emissions from the entire land use sector in Costa Rica in the 1990s. This calculation provides an indication of the potential recovery of carbon stocks which mangrove restoration efforts may offer in the country. Expanding this research to other Central American countries, and analyzing the historical land use dynamics along coastal areas together with the potential impacts of climate change on these ecosystems would yield similar region-wide estimates of greenhouse gas emissions and mitigation potential that could be used to improve the design of climate change mitigation projects in coastal areas.

Cifuentes, M.

2012-12-01

59

Preservation or Conversion? Valuation and Evaluation of a Mangrove forest in the Philippines  

Microsoft Academic Search

Mangrove ecosystems are rapidly declining in many parts of the world. This has resulted in the loss of important environmental and economic products and services including forest products, flood mitigation and nursery grounds for fish. The aquaculture industry was the single biggest threat to mangroves in the Philippines until 1981 when conversion of the remaining mangrove stands was prohibited by

Janssen Ron; JOSE E. PADILLA

1999-01-01

60

Changes in benthic assemblages near boardwalks in temperate urban mangrove forests  

Microsoft Academic Search

Boardwalks allow easy access to mangrove forests and are built to enhance their recreational and educational potential. Nevertheless, little is known about any potential impacts of boardwalks on plants and animals in the mangrove habitat. This study investigated the effects of disturbances associated with boardwalks on mangrove macrofauna. Influences at several spatial scales were examined by testing hypotheses about macrofaunal

B. P Kelaher; M. G Chapman; A. J Underwood

1998-01-01

61

Plastic debris retention and exportation by a mangrove forest patch.  

PubMed

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

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

2014-01-15

62

Structure and dynamics of mangrove forests along a flooding gradient  

Microsoft Academic Search

The zonation patterns ofAvicennia bicolor andRhizophora racemosa were studied in a mangrove forest on the Pacific Coast of Costa Rica. Comparisons were made between the establishment, survival,\\u000a and growth of both species in three plots, 1 ha each, located along the flooding gradient. Based on cohort analysis and reciprocal\\u000a planting observations, it was concluded that species zonation was primarily regulated

Jorge A. Jiménez; Krista Sauter

1991-01-01

63

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

NASA Astrophysics Data System (ADS)

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.

Thu, Phan Minh; Populus, Jacques

2007-01-01

64

Experimental study on tsunami attenuation by mangrove forest  

NASA Astrophysics Data System (ADS)

Laboratory experiments on the effectiveness of mangroves to reduce tsunami energy were performed. A complex tree structure of Rhizophora sp. was parameterized using the stiff structure assumption (root system and trunk) for different submerged root volume ratios and frontal tree areas. The hydraulic resistance of the prototype and the parameterized models under steady flow conditions was compared and the most appropriate parameterized model in terms of both equivalent flow resistance and practical feasibility was selected for further investigation. The damping performance of the mangrove forest was determined from laboratory tests performed synchronously in a twin-wave flumes (with and without the forest model in 1 and 2 m-wide wave flumes, respectively) for varying incident height of solitary wave, water depth and forest width. The role of the different types of wave evolution modes on wave damping is discussed based on the measurements of the forces exerted on the single tree models along the entire forest width. A new approach for the wave transmission coefficient, which is based on the ratio of the forces exerted on the trees placed in the last and first forest row, is proposed. In the paper, the most important results of the tree parameterization procedure and the wave flume experiments are discussed.

Husrin, S.; Strusi?ska, A.; Oumeraci, H.

2012-10-01

65

Sediment biogeochemistry in an East African mangrove forest (Gazi Bay, Kenya)  

Microsoft Academic Search

The biogeochemistry of mangrove sediments was investigated in several mangrove forest communities in Gazi Bay, a coastal lagoon in Kenya, Africa. Carbon dioxide fluxes, sediment median grain sizes, sedimentary organic carbon, nitrogen and phosphorus contents and pore-water characteristics (ammonium, nitrate, sulfate and chloride) could be related to forest type. Mangrove sediments have pH values that range from 3.5 to 8.3

Jack J. Middelburg; Joop Nieuwenhuize; Frederik J. Slim; Boaz Ohowa

1996-01-01

66

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

USGS Publications Warehouse

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.

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

2010-01-01

67

Corticioid fungi (Basidiomycota) in mangrove forests of the islands of Iriomote and Okinawa, Japan  

Microsoft Academic Search

Sixteen species of corticioid fungi (Basidiomycota) were collected from mangrove forests in the islands of Iriomote and Okinawa, Japan. All the species are new records for the Japanese mangrove forests. Of these species, 6 species are newly reported from Japan: Cerocorticium molle, Gloeocystidiellum moniliforme, G. wakullum, Hyphoderma ayresii, Phanerochaete tropica, and Phlebia acanthocystis. Their morphological descriptions, illustrations, and remarks based

Nitaro Maekawa; Hiroto Suhara; Kazuhiko Kinjo; Ryuichiro Kondo

2003-01-01

68

EXTENDED BENEFIT-COST ANALYSIS OF MANAGEMENT ALTERNATIVES: PAGBILAO MANGROVE FOREST  

Microsoft Academic Search

The rapid decline in the area of mangrove forests and swamps in the Philippines has been primarily due to their conversion to other uses. Consequently, important environmental and economic goods and services, including forest products, flood mitigation and nursery grounds for fish, have been lost. The aquaculture industry was the single biggest threat to mangroves in the country until several

Jose E. Padil; Ron Janssen

69

Species diversity of culturable endophytic fungi from Brazilian mangrove forests.  

PubMed

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

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

70

Identification of Lightning Gaps in Mangrove Forests Using Airborne LIDAR Measurements  

NASA Astrophysics Data System (ADS)

Mangrove forests are highly dynamic ecosystems and change frequently due to tropical storms, frost, and lightning. These factors can cause gaps in mangrove forests by damaging trees. Compared to gaps generated by storms and frost, gaps caused by lightning strikes are small, ranging from 50 to 300 m2. However, these small gaps may play a critical role in mangrove forest dynamics because of the frequent occurrence of lightning in tropical areas. It has been hypothesized that the turnover of mangrove forests is mainly due to the death and regeneration of trees in lightning gaps. However, there is a lack of data for gap occurrence in mangrove forests to verify this hypothesis. It is impractical to measure gaps through a field survey on a large scale because of the logistic difficulties of muddy mangrove forests. Airborne light detection and ranging (LIDAR) technology is an effective alternative because it provides direct measurements of ground and canopy elevations remotely. This study developed a method to identify lightning gaps in mangrove forests in terms of LIDAR measurements. First, LIDAR points are classified into vegetation and ground measurements using the progressive morphological filter. Second, a digital canopy model (DCM) is generated by subtracting a digital terrain model (DTM) from a digital surface model (DSM). The DSM is generated by interpolating raw LIDAR measurements, and DTM is produced by interpolating ground measurements. Third, a black top-hat mathematical morphological transformation is used to identify canopy gaps. Comparison of identified gap polygons with raw LIDAR measurements and field surveys shows that the proposed method identifies lightning gaps in mangrove forests successfully. The area of lightning gaps in mangrove forests in Everglades National Park is about 3% of total forest area, which verifies that lightning gaps play a critical role in mangrove forest turnover.

Zhang, K.

2006-12-01

71

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

USGS Publications Warehouse

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 possible areas for conservation, restoration and rehabilitation. ?? 2007 The Authors.

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

2008-01-01

72

Litter dynamics and forest structure of the introduced Sonneratia caseolaris mangrove forest in Shenzhen, China  

NASA Astrophysics Data System (ADS)

For the purpose of mangrove restoration in China, Sonneratia caseolaris has been introduced and planted in Guangdong Province outside and north of its native habitat, Hainan Province. We monitored the litter fall and forest structure of this S. caseolaris forest in Shenzhen City, Guangdong Province, China, from 1996 to 2005. The annual fluctuation in litter fall increased with increases in air temperature from spring to early summer, and reached a maximum in autumn when the fruits matured. The total litter fall was significantly affected by air temperature, day length, and evaporation, rainfall in the previous month and by typhoons. In 1998, the sixth year after cultivation, the total litter production of the mature S. caseolaris forest significantly increased. The mean annual total litter production during 1998-2005 was 15.1 t ha -1 yr -1, among which, leaves and reproductive materials contributed more than 80% of the total. During the ten years of study, the DBH (diameter at 1.30 m from ground level) and tree height of S. caseolaris increased from 5.2 cm to 18.3 cm, and from 4.5 m to 13.4 m, respectively. The litter fall production was strongly correlated with forest structure parameters, such as DBH, tree height, and crown area. The R value (the ratio of the maximum total litter fall to the minimum in the same community during the investigation periods) of S. caseolaris in the present study was 1.98, indicating a low annual variation of litter fall during these ten years.

Chen, Luzhen; Zan, Qijie; Li, Mingguang; Shen, Jinyu; Liao, Wenbo

2009-11-01

73

Use of Landsat TM imagery as a tool for mangrove forest mapping ; a case study of Ehotile island in Côte d'Ivoire  

NASA Astrophysics Data System (ADS)

The integrated management of coastal zone requires a good coastal landscape knowledge. Mangroves in Côte d'Ivoire are valuable economic resources because of their high biomass production and their being a prolific fish habitat. They also play major role in the food chains and the fight against coastal erosion. However, mangroves are considered a hostile environment and thus are often cut down by man. Many restoration and protection efforts are underway. The present study is a remote sensing approach to map the mangroves of the Ehotilé Islands (Iles Ehotilé) in Côte d'Ivoire from the Landsat 7 scene 195-56 acquired on February 2nd, 2000. A multispectral analysis (Principal Component Analysis, Colour composites, Vegetation indices) was performed on the digital image which was later classified into nine (9) information classes (mangroves, swampy forest, forest, degraded forest, farmlands and/or fallows, grasslands, urban areas, seashore, water). The overall accuracy of the supervised classification is estimated at 93 percent. On the final classified image, areas predominantly covered by mangroves (Rhizophora racemosa) amount to 848 ha out of the 5715 ha of the study area. Remote sensing offers a valuable tool to monitor and map the mangrove ecosystems and land cover in tropical regions. Keywords: Mangroves, Remote sensing, Mapping, Classification, Landsat 7, Côte d'Ivoire, Iles Ehotilé, Land cover, coastal zone.

Kwassi, A.; Blivi, A.

74

Estimating leaf area index of a degraded mangrove forest using high spatial resolution satellite data  

Microsoft Academic Search

Leaf Area Index (LAI) values from 124 mangrove plots were acquired within a degraded mangrove forest of the Agua Brava Lagoon System of Nayarit (Mexico) using a hand held LAI-2000 Plant Canopy Analyzer. For each plot, two values of LAI were calculated to represent approximate half radii (180°) ground coverage of 8m and 15m. The location of each plot was

John M. Kovacs; Francisco Flores-Verdugo; Jinfei Wang; Lance P. Aspden

2004-01-01

75

Nutrients and heavy metal contamination of plants and sediments in Futian mangrove forest  

Microsoft Academic Search

An ecological survey was carried out to determine the levels of nutrients and heavy metals in the sediments and leaf tissues of two dominant mangrove plant species, Kandelia candel and Aegiceras corniculatum, in Futian mangrove forest, Shenzhen, the People's Republic of China. The spatial and seasonal variations of these elements were also investigated. The results show that there was no

N. F. Y. Tam; S. H. Li; C. Y. Lan; G. Z. Chen; M. S. Li; Y. S. Wong

1995-01-01

76

Effect of boardwalks on the semaphore crab Heloecius cordiformis in temperate urban mangrove forests  

Microsoft Academic Search

Boardwalks are used in management of mangrove forests because they are thought to solve problems of access by people while promoting recreational and educational opportunities. Nevertheless, boardwalks and the people using them may have negative effects on plants and animals of the mangrove habitat. This study investigated the potential impact of a boardwalk on the distribution and abundance of the

B. P Kelaher; A. J Underwood; M. G Chapman

1998-01-01

77

Flow routing in mangrove forests: A field study in Trang province, Thailand  

NASA Astrophysics Data System (ADS)

Flow routing in mangrove forests has great implications for the transport and distribution of sediments and nutrients and hence for mangroves' development and persistence. Whereas previous studies were limited to the creeks, supposedly feeding the surrounding mangroves, this study demonstrates the contribution of biogeophysical impacts on flow routing through estuarine mangroves. We present the results of a field campaign covering three pristine mangrove sites in two estuaries in Trang province, Thailand. The sites range from a mangrove forest elevated above mean sea level with steep cliffs and incised by tidal creeks, to smoothly inclining mangroves fronted by extensive mudflats and showing a clear vegetation zonation starting below mean sea level. It is shown how flow routing through estuarine mangroves is impacted by biogeophysical factors; elevation, exposure and vegetation. Within the higher elevated mangroves, creek flow prevails when water levels remain below a dense vegetation layer at the mangrove fringe bordering the estuary. Sheet flow prevails when this threshold is exceeded and direct water exchange takes place. The low-lying sites do not feature creeks and tidal flows are typically sheet flows, being susceptible to forcing by river discharges. With decreasing water depths and/or increasing vegetation densities, the effects of this forcing are reduced and flow velocities follow the vegetation induced cross-shore water level gradients. Flow velocities within the creeks are up to an order of magnitude greater than those within the vegetation, where velocities decrease progressively with increasing vegetation densities. Particular vegetation and elevation characteristics cause irregular velocity variations along the vertical, within the vegetation as well as in the creeks. Tentative tidal flux calculations demonstrate the significant contribution of creek flow to the total tidal prism in higher elevated mangroves. By explicitly quantifying and mapping flow routing through mangrove forests, this study provides observational evidence for flow routing phenomena that have been postulated in previous studies.

Horstman, Erik M.; Dohmen-Janssen, C. Marjolein; Hulscher, Suzanne J. M. H.

2013-12-01

78

Mangroves among the most carbon-rich forests in the tropics  

NASA Astrophysics Data System (ADS)

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.

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

2011-05-01

79

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

PubMed

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

Samson, Maricar S; Rollon, Rene N

2008-06-01

80

Emersion in the Mangrove Forest Fish 'Rivulus marmoratus': A Unique Response to Hydrogen Sulfide.  

National Technical Information Service (NTIS)

The mangrove forest fish Rivulus marmoratus (Cyprinodontidae) has frequently been observed out of water, a phenomenon generally attributed to habitat drying. The authors tested the hypothesis that hydrogen sulfide, a substance characteristically found in ...

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

1987-01-01

81

EMERSION IN THE MANGROVE FOREST FISH 'RIVULUS MARMORATUS': A UNIQUE RESPONSE TO HYDROGEN SULFIDE  

EPA Science Inventory

The mangrove forest fish Rivulus marmoratus (Cyprinodontidae) has frequently been observed out of water, a phenomenon generally attributed to habitat drying. The authors tested the hypothesis that hydrogen sulfide, a substance characteristically found in their environment, can se...

82

Cyanobacterial diversity in the phyllosphere of a mangrove forest.  

PubMed

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

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

2012-05-01

83

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

USGS Publications Warehouse

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.

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

2005-01-01

84

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

USGS Publications Warehouse

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 Publishing Ltd.

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

2011-01-01

85

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

USGS Publications Warehouse

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.

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

2011-01-01

86

Tsunami inundation and sediment transport in vicinity of coastal mangrove forest  

USGS Publications Warehouse

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.

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

2007-01-01

87

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

NASA Astrophysics Data System (ADS)

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 recovery category that implied the homogeneous pattern or uniform reforestation was observed in the seriously damaged area where most of the mangrove trees were swept away during the tsunami. This pattern covered approximately 50.35 % of the total reforested area. The NDVI time series of the uniform or homogeneous reforested mangrove at the sampled plots has gradually increased after 2005. The fluctuating recovery category that implied the heterogeneous pattern or non-uniform reforestation was observed in partially damaged areas where some of the mangrove trees were swept away and broken but still some trees were remained in the area. The heterogeneous patterns covered approximately 49.65 % of the total reforested area.

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

2011-07-01

88

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

USGS Publications Warehouse

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.

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

2005-01-01

89

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

PubMed

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

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

2013-03-15

90

Carbon Accumulation in Mangrove Soil during Forest Maturity: New Insights from Afforestation Projects in Southern China  

NASA Astrophysics Data System (ADS)

Mangrove forests have high rates of carbon (C) sequestration, and long-term C storage in mangrove soils can span millennia. Our knowledge of C accumulation in mangrove soils is limited however, by a scarcity of direct measurements and because the existing body of data appears to be biased toward high C systems. Furthermore, very little is known about C accumulation rates in young forests following afforestation. We collected soil data from Chinese mangrove afforestation projects and conducted a literature review with the aims of 1) quantifying soil C accumulation following afforestation, and 2) characterizing young, relatively low-C systems to contribute to global estimates of mangrove soil C. We collected soil cores (depth range 10 to 100 cm) at Dongzhaigang (Hainan Province) and Futian (Guangdong Pronvince) National Mangrove Reserves, where forests plots ranged in age from 0 (unforested mudflat) to 60 years. At Futian, soil data were collected annually from pre-planting through 5 years old, and neighboring forests were used to characterize older forests (space for time chronosequence). At Dongzhaigang, a space for time approach was used to compare three neighboring forests. Preliminary data from Dongzhaigang show average to slightly high rates of soil C sequestration (196 to 319 g C m-2 yr-1), compared to current global averages for all mangroves. In our literature review, we found 10 papers containing soil C data for at least two forest ages, for a total of 19 sites. Soil C increased with forest age at almost all sites, and increased from pre-planting to year 5 at all sites of that age group. This trend differs from terrestrial forests, which on average show a decrease in soil C for the first five years after afforestation. Several reviewed studies and our own field data show soil C densities (%C per volume) near 2% decades after afforestation, which is several times lower than most current global averages for all mangrove soil. Our research indicates that young mangrove forests can sequester significant amounts of C in soil with positive sequestration rates following afforestation. However, despite significant sequestration, soil C density remains lower than current global averages decades after afforestation.

Lunstrum, A.; Chen, L.; Yang, Y.

2012-12-01

91

Soil salinity and pH in Japanese mangrove forests and growth of cultivated mangrove plants in different soil conditions  

Microsoft Academic Search

Soil conditions of mangrove forests in southern Japan were found to correlate largely with zonal distributions of the species.Kandelia candel grew in soils with low salinity and low pH,Avicennia marina, Rhizophora stylosa andSonneratia alba in soils with high salinity and high pH, andBruguiera gymnorrhiza in soil with a wide range of pH but limited range of salinity.Lumnitzera racemosa colonized soil

Satoru Wakushima; Susumu Kuraishi; Naoki Sakurai

1994-01-01

92

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

Microsoft Academic Search

Given the alarming global rates of mangrove forest loss it is important that resource managers have access to updated information\\u000a regarding both the extent and condition of their mangrove forests. Mexican mangroves in particular have been identified as\\u000a experiencing an exceptional high annual rate of loss. However, conflicting studies, using remote sensing techniques, of the\\u000a current state of many of

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

2009-01-01

93

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

Microsoft Academic Search

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

Inga Nordhaus; Matthias Wolff; Karen Diele

2006-01-01

94

Local Management of Mangrove Forests in the Philippines: Successful Conservation or Efficient Resource Exploitation?  

Microsoft Academic Search

Recent environmental narratives suggest that local people are effective stewards of forest resources. Local restoration and management of mangrove forests, in particular, are now widely advocated as a solution to achieve both economic and environmental conservation goals. This paper presents findings from a study of 2 coastal sites in the Philippines that are renowned and often showcased as success stories

Bradley B. Walters

2004-01-01

95

Soil-plant interactions in a neotropical mangrove forest: iron, phosphorus and sulfur dynamics  

Microsoft Academic Search

We examined soil porewater concentrations of sulfate, alkalinity, phosphorus, nitrogen, and dissolved organic carbon and\\u000a solid phase concentrations of pyrite in relation to mangrove species distributions along a 3.1-km-long transect that traversed\\u000a a 47.1-km2 mangrove forest in the Dominican Republic. Iron, phosphorus, and sulfur dynamics are closely coupled to the activity of sulfate-reducing\\u000a bacteria, the primary decomposers in anoxic soils

Ruth E. Sherman; Timothy J. Fahey; Robert W. Howarth

1998-01-01

96

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

NASA Astrophysics Data System (ADS)

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 environmental conditions.

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

2013-03-01

97

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

USGS Publications Warehouse

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 environmental conditions.

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

2013-01-01

98

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

USGS Publications Warehouse

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 findings are not only relevant to the coastal environments found in the Caribbean region, but our assessment methods may be useful for developing site-specific information to restore disturbed mangrove forests worldwide, especially given the large pool of mangrove associates (>45 genera) available for screening. ?? 2007 by the Ecological Society of America.

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

2007-01-01

99

A 7 year record of above-ground net primary production in a southeastern Mexican mangrove forest  

Microsoft Academic Search

Spatial and temporal variations in net above-ground primary production (NPP) and litter turnover rate were studied, from 1987 to 1993, in a mangrove forest bordering Laguna de Terminos, Mexico. NPP, the sum of total litter fall and wood production, was measured over the entire study period in three zones in a basin forest: zone I, where Rhizophora mangle (red mangrove)

J. W. Day; Carlos Coronado-Molina; F. R. Vera-Herrera; R. Twilley; V. H. Rivera-Monroy; H. Alvarez-Guillen; R. Day; W. Conner

1996-01-01

100

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

PubMed

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

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

2006-12-01

101

The influence of crabs on litter processing in high intertidal mangrove forests in tropical Australia  

Microsoft Academic Search

Measurements of litter fall and litter removal by crabs, in conjunction with estimates of litter decay by microbes and tidal export of litter from three high-intertidal mangrove forests were made during a year-long study in tropical northeastern Australia. In forests dominated by Ceriops tagal and Bruguiera exaristata, litter standing stocks remained low on the forest floor (mean 6 g·m-2), although

A. I. Robertson; P. A. Daniel

1989-01-01

102

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

Microsoft Academic Search

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)

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

1995-01-01

103

Influences of tidal energy advection on the surface energy balance in a mangrove forest  

NASA Astrophysics Data System (ADS)

Mangrove forests are ecosystems susceptible to changing water levels and temperatures due to climate change as well as perturbations resulting from tropical storms. Numerical models can be used to project mangrove forest responses to regional and global environmental changes, and the reliability of these models depends on surface energy balance closure. However, for tidal ecosystems, the surface energy balance is complex because the energy transport associated with tidal activity remains poorly understood. This study aimed to quantify impacts of tidal flows on energy dynamics within a mangrove ecosystem. To address the research objective, an intensive study was conducted in a mangrove forest located along the Shark River in the Everglades National Park, FL. Forest-atmosphere energy exchanges were quantified with an eddy covariance system deployed on a flux tower. The lateral energy transport associated with tidal activity was calculated based on a coupled mass and energy balance approach. The mass balance included tidal flows and accumulation of water on the forest floor. The energy balance included temporal changes in enthalpy, resulting from tidal flows and temperature changes in the water column. By serving as a net sink or a source of available energy, tidal flows reduced the impact of high radiational loads on the mangrove forest. Including tidal energy advection in the surface energy balance improved the 30-min daytime energy closure from 73% to 82% over the study period. Also, the cumulative sum of energy output improved from 79% to 91% of energy input during the study period. Results indicated that tidal inundation provides an important mechanism for heat removal and that tidal exchange should be considered in surface energy budgets of coastal ecosystems. Results also demonstrated the importance of including tidal energy advection in mangrove biophysical models that are used for predicting ecosystem response to changing climate and regional freshwater management practices.

Barr, J. G.; Fuentes, J. D.; DeLonge, M. S.; O'Halloran, T. L.; Barr, D.; Zieman, J. C.

2012-08-01

104

Summertime influences of tidal energy advection on the surface energy balance in a mangrove forest  

NASA Astrophysics Data System (ADS)

Mangrove forests are ecosystems susceptible to changing water levels and temperatures due to climate change as well as perturbations resulting from tropical storms. Numerical models can be used to project mangrove forest responses to regional and global environmental changes, and the reliability of these models depends on surface energy balance closure. However, for tidal ecosystems, the surface energy balance is complex because the energy transport associated with tidal activity remains poorly understood. This study aimed to quantify impacts of tidal flows on energy dynamics within a mangrove ecosystem. To address the research objective, an intensive 10-day study was conducted in a mangrove forest located along the Shark River in the Everglades National Park, FL, USA. Forest-atmosphere turbulent exchanges of energy were quantified with an eddy covariance system installed on a 30-m-tall flux tower. Energy transport associated with tidal activity was calculated based on a coupled mass and energy balance approach. The mass balance included tidal flows and accumulation of water on the forest floor. The energy balance included temporal changes in enthalpy, resulting from tidal flows and temperature changes in the water column. By serving as a net sink or a source of available energy, flood waters reduced the impact of high radiational loads on the mangrove forest. Also, the regression slope of available energy versus sink terms increased from 0.730 to 0.754 and from 0.798 to 0.857, including total enthalpy change in the water column in the surface energy balance for 30-min periods and daily daytime sums, respectively. Results indicated that tidal inundation provides an important mechanism for heat removal and that tidal exchange should be considered in surface energy budgets of coastal ecosystems. Results also demonstrated the importance of including tidal energy advection in mangrove biophysical models that are used for predicting ecosystem response to changing climate and regional freshwater management practices.

Barr, J. G.; Fuentes, J. D.; DeLonge, M. S.; O'Halloran, T. L.; Barr, D.; Zieman, J. C.

2013-01-01

105

Energy dissipation in non-uniform mangrove forests of arbitrary depth  

NASA Astrophysics Data System (ADS)

This study aims to develop a predictive model of wave propagation through non-uniform forest in water of arbitrary depth. The theoretical model solves a full boundary value problem for wave propagation with dissipation for non-uniform mangrove forest and arbitrary water depth. In particular, wave-trunk interaction and wave breaking were found to be the dominant dissipation mechanisms. A modified mild-slope equation including dissipation is applied for wave model over changing water depth within the mangrove forest. The non-linear governing equations for wave-trunk interactions are linearised using the concept of stochastic minimalisation. The numerical results of the model are verified and compared with the experimental wave data in Can Gio Mangrove Biosphere Reserve, Southern Vietnam. The results for wave height, wave spectrum and wave-induced velocities as well as for the coefficients of transmission and reflection suggest that most of the energy is dissipated within the mangrove forest even at relatively small distance. The effect of wave breaking plays a more important role on wave attenuation in sparse forest, however, it is smaller compared to the effect of wave-trunk interactions in the denser forest.

Vo-Luong, Phuoc; Massel, Stanislaw

2008-11-01

106

The Role of Mangrove Ecosystems: Properties of a Mangrove Forest in South Florida.  

National Technical Information Service (NTIS)

A suite of parameters describing the physical environment and the structure and function of a mangrove ecosystem was evaluated. The resulting data were evaluated in terms of the dynamic properties of the ecosystem with emphases on auxillary energy sources...

A. E. Lugo S. C. Snedaker

1973-01-01

107

Valuing mangrove ecosystem services: linking nutrient retention function of mangrove forests to enhanced agroecosystem production  

Microsoft Academic Search

Mangroves are highly productive wetland ecosystems strategically located at the interface between land and sea. They play\\u000a an important role in the biogeochemical cycles of the coastal environment, acting as sources of nutrients to adjacent marine\\u000a and terrestrial ecosystems through active and passive transport. We examined the nutrient contents in mangrove and nonmangrove\\u000a soils in and around the Bhitarkanika National

Syed Ainul Hussain; Ruchi Badola

2008-01-01

108

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

NASA Astrophysics Data System (ADS)

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 below-ground nutrients, rapid rates of nutrient flux and microbial decomposition, complex and highly efficient biotic controls, self-design and redundancy of keystone species, and numerous feedbacks, all contribute to mangrove resilience to various types of disturbance.

Alongi, Daniel M.

2008-01-01

109

How mangrove forests adjust to rising sea level  

USGS Publications Warehouse

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.

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

2014-01-01

110

How mangrove forests adjust to rising sea level.  

PubMed

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. PMID:24251960

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

2014-04-01

111

Mangroves of Laguna Joyuda.  

National Technical Information Service (NTIS)

Laguna Joyuda mangroves provide opportunity to explore relations beween site factors other than climate and mangrove structure and dynamics. Our analysis reviews (1) the area and environment of Laguna Joyuda mangroves, (2) forest structure, (3) litter dyn...

A. E. Lugo J. C. Musa

1993-01-01

112

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

PubMed

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)). PMID:24430724

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

2014-05-01

113

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

NASA Astrophysics Data System (ADS)

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 development of sustainable livelihood options for local communities from the conservation of critical ecosystems such as mangroves.

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

2012-01-01

114

Assessing the consequences of hurricane-induced fragmentation of mangrove forest on habitat and nekton in Big Sable Creek, Florida  

Microsoft Academic Search

The passage of two major hurricanes across southwest Florida (Category 5, Labor Day Hurricane of 1935; Category 4, Hurricane Donna 1960) resulted in fragmentation of mangrove forest at Big Sable Creek, Everglades National Park. Over time forest fragmentation led to forest loss and patchy conversion to unvegetated mudflats. My goal was to determine the consequence of forest fragmentation on nekton

Noah L Silverman

2006-01-01

115

Net primary productivity of two mangrove forest stands on the northwestern coast of Sri Lanka  

Microsoft Academic Search

Productivity studies were carried out from September, 1985 to August, 1987 in two mangrove stands, i.e. estuarine and island fringing, in Dutch bay, a lagoon situated on the northwestern coast of Sri Lanka. Net above-ground primary productivity was measured by monitoring litterfall and above-ground biomass increment. The average annual rate of litterfall in the estuarine and island-fringing mangrove stands are

M. D. Amarasinghe; S. Balasubramaniam

1992-01-01

116

Interstitial water and hydrochemistry of a mangrove forest and adjoining water system, south west coast of India  

Microsoft Academic Search

Eh, pH, salinity, total alkalinity, dissolved O2, NO2\\u000a –, PO4\\u000a –3, SiO2 and NH4\\u000a + of waters from a mangrove forest, an estuary and a creek connecting the mangrove forest and the estuary have been measured.\\u000a Further, the chemistry of interstitial waters of surficial and core sediments from the mangrove forest have been analyzed\\u000a for the above parameters, except dissolved

K. A. Bava; P. Seralathan

1999-01-01

117

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

Microsoft Academic Search

Summary 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 im- portant and productive forest resource in many tropical and subtropical countries, sustain a high ratio of root to shoot bio- mass which may indicate that root respiration is a particularly important component

CATHERINE E. LOVELOCK; ROGER W. RUESS; ILKA C. FELLER

118

Separating live and dead fine roots using colloidal silica: an example from mangrove forests  

Microsoft Academic Search

Separation of live and dead fine roots is a critical process in studies of fine root dynamics, but many studies use subjective visual cues during time-consuming hand sorting of root samples, or do not attempt separation at all. Here we describe a method for separating fine roots from mangrove forests using solutions of colloidal silica. The method removed 96±2% (standard

A. I. Robertson; P. Dixon

1993-01-01

119

An evaluation of management strategies for recreational use of a mangrove forest in Mexico  

Microsoft Academic Search

This paper proposes the use of stated preference techniques for analyzing regulation and negotiation schemes in a specific mangrove forest in northwest Mexico. This proposal will help people involved in environmental management simulate the welfare outcomes for society that may result under different management strategies. To analyze the usefulness of this proposal, its application to a nature-based recreational area in

Enrique Sanjuro

2009-01-01

120

Biochemical properties of soils of undisturbed and disturbed mangrove forests of South Andaman (India)  

Microsoft Academic Search

Studies on soil quality of mangrove forests would be of immense use in minimizing soil degradation and in adopting strategies for soil management at degraded sites. Among the various parameters of soil quality, biological and biochemical soil properties are very sensitive to environmental stress and provide rapid and accurate estimates on changes in quality of soils subjected to degradation. In

R. Dinesh; S. G. Chaudhuri; A. N. Ganeshamurthy; S. C. Pramanik

2004-01-01

121

A survey method for estimating potential levels of mangrove forest primary production  

Microsoft Academic Search

Measurements of net photosynthesis in mangrove communities by direct methods is technically and logistically difficult. Recording litter fall alone neglects other important components of production. A method has been developed which lends itself to ready application for obtaining survey estimates of photosynthetic yield. The procedure involves measurement of light attenuation through forest canopies attributable to photosynthetic utilization and standardized against

J. S. Bunt; K. G. Boto; G. Boto

1979-01-01

122

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

PubMed Central

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

Nyari, Arpad S.; Joseph, Leo

2012-01-01

123

Organic carbon accumulation and metabolic pathways in sediments of mangrove forests in southern Thailand  

Microsoft Academic Search

Rates of organic carbon accumulation, mineralization and burial in sediments were examined during dry and wet seasons in four mangrove forests of a shallow-water embayment (Ao Sawi) in southern Thailand. Mass sediment accumulation (MAR), estimated from 210Pb and 137Cs profiles, was rapid at all forests, ranging from 2.9 to 7.6kgm?2yr?1; mixed layer sediment thicknesses ranged from 16 to 38cm. Total

D. M Alongi; G Wattayakorn; J Pfitzner; F Tirendi; I Zagorskis; G. J Brunskill; A Davidson; B. F Clough

2001-01-01

124

Mapping Disturbances in a Mangrove Forest Using Multi-Date Landsat TM Imagery  

Microsoft Academic Search

To evaluate the accounts of local fishermen, Landsat TM images (1986, 1993, 1999) were examined to assess potential losses\\u000a in the mangrove forests of the Teacapán–Agua Brava lagoon system, Mexico. A binary change mask derived from image differencing\\u000a of a band 4\\/3 ratio was employed to calculate any changes within this forested wetland. The results indicate that by 1986\\u000a approximately

JOHN M. KOVACS; JINFEI WANG; MANUEL BLANCO-CORREA

2001-01-01

125

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

NASA Astrophysics Data System (ADS)

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 acts as a sink of inorganic nitrogen and as a source of dissolved and particulate nitrogen.

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

126

The ecology of fiddler crab Uca forcipata in mangrove forest  

NASA Astrophysics Data System (ADS)

Fiddler crab burrows increase oxygen dispersion in anoxic mangrove sediment and promote iron reduction and nitrification process over sulfate reduction in subsurface sediment. Therefore it is expected to accelerate decomposition rate under oxic and suboxic conditions. In this study the effect of environmental parameters on the local distribution of U. forcipata and subsequently the effect of crab burrows on sediment characteristics were investigated. Our result indicated that U. forcipata prefers to live in the open mudflats under the shade of mangrove trees. The most important factors determining their presence were sediment texture, porosity, organic content, water content, carbon content and temperature. Measurement of redox potential and iron pools clearly indicated a distinct oxidized layer around burrows although sediment porosity, organic and water content did not differ significantly between burrowed and non-burrowed mudflats and even among the burrow profiles. This result implies the oxidation created by burrowing activity of U .forcipata was not efficient to change physical properties of mangrove sediments.

Mokhtari, Mohammad; Ghaffar, Mazlan Abd; Usup, Gires; Cob, Zaidi Che

2013-11-01

127

Structure of mangrove trees and forests in Micronesia  

Microsoft Academic Search

Volume equations were constructed for five species of mangrove trees on volcanic high islands of Micronesia in the north Pacific Ocean, where islands that span a distance of more than 3000km from east to west are characterized by a gradient of rainfall from 3080 to 5250mm\\/year and a range of typhoon frequency from less than one per century to several

Thomas G. Cole; Katherine C. Ewel; Nora N. Devoe

1999-01-01

128

Characterisation of three mosquitocidal Bacillus strains isolated from mangrove forest  

Microsoft Academic Search

In an attempt to isolate mosquitocidal bacteria, 460 samples of soil, leaf and water were collected from mangrove habitats of Andaman–Nicobar Islands, India. Out of a total number of 857 bacteria screened, three Bacillus strains showed mosquitocidal activity at promising levels. Two of them were identified, morphologically and biochemically, as Bacillus subtilis, whereas one was Bacillus thuringiensis. These strains were

I. Geetha; G. Prabakaran; K. P. Paily; A. M. Manonmani; K. Balaraman

2007-01-01

129

Petroleum pollution in mangrove forests sediments from Qeshm Island and Khamir Port-Persian Gulf, Iran.  

PubMed

The concentrations of total polycyclic aromatic hydrocarbons (PAHs) and 22 individual PAH compounds in 42 surface sediments collected from the mangrove forest of Qeshm Island and Khamir Port (Persian Gulf) were analyzed. PAHs concentrations ranged from 259 to 5,376 ng g(-1) dry weight with mean and median values of 1,585 and 1,146 ng g(-1), respectively. The mangrove sediments had higher percentages of lower molecular weight PAHs and the PAH profiles were dominated by naphthalene. Ratio values of specific PAH compounds were calculated to evaluate the possible source of PAH contamination. This ratios suggesting that the mangrove sediments have a petrogenic input of PAHs. Sediment quality guidelines were conducted to assess the toxicity of PAH compounds. The levels of total PAHs at all of stations except one station, namely Q6, were below the effects range low. Also, concentrations of naphthalene in some stations exceeded the effects range median. PMID:22930186

Ebrahimi-Sirizi, Zohreh; Riyahi-Bakhtiyari, Alireza

2013-05-01

130

Mosquitoes of the mangrove forests of India: part six--Kundapur, Karnataka and Kannur, Kerala.  

PubMed

Mosquitoes of 26 species belonging to 16 subgenera and 11 genera were recorded in the Kundapur mangroves of Karnataka, and 17 species belonging to 11 subgenera and 7 genera were recorded in the mangroves of Kannur, Kerala along the west coast of India. Genera recorded were Aedes, Anopheles, Armigeres, Culex, Heizmannia, Lutzia, Mansonia, Ochlerotatus, Tripteroides, Uranotaenia, and Verrallina. Species common to both mangrove forests were Ae. albopictus, Ae. vittatus, An. jamesi, Ar. subalbatus, Cx. gelidus, Cx. infantulus, Cx. pseudovishnui, Cx. sitiens, Cx. tritaeniorhynchus, Oc. wardi, Ur. atra, and Ve. luguhris. Tree holes and swamp pools were the common larval habitats, with more species occurring in tree holes in Kundapur than in Kannur. Adults of Ae. albopictus, Ae. vittatus, Ar. aureolineatus, Ar. subalbatus, Cx. bitaeniorhynchus, Cx. sitiens, Ma. uniformis, and Ve. lugubris bloodfed on humans. PMID:17304922

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

2006-12-01

131

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

Microsoft Academic Search

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

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

1990-01-01

132

Dissolved inorganic carbon dynamics in the waters surrounding forested mangroves of the Ca Mau Province (Vietnam)  

NASA Astrophysics Data System (ADS)

Dissolved inorganic carbon (DIC) and ancillary data were obtained during the dry and rainy seasons in the waters surrounding two 10-year-old forested mangrove sites (Tam Giang and Kiên Vàng) located in the Ca Mau Province (South-West Vietnam). During both seasons, the spatial variations of partial pressure of CO 2 (pCO 2) were marked, with values ranging from 704 ppm to 11481 ppm during the dry season, and from 1209 ppm to 8136 ppm during the rainy season. During both seasons, DIC, pCO 2, total alkalinity (TAlk) and oxygen saturation levels (%O 2) were correlated with salinity in the mangrove creeks suggesting that a combination of lower water volume and longer residence time (leading to an increase in salinity due to evaporation) enhanced the enrichment in DIC, pCO 2 and TAlk, and an impoverishment in O 2. The low O 2 and high DIC and pCO 2 values suggest that heterotrophic processes in the water column and sediments controlled these variables. The latter processes were meaningful since the high DIC and TAlk values in the creek waters were related to some extent to the influx of pore waters, consistent with previous observations. This was confirmed by the stochiometric relationship between TAlk and DIC that shows that anaerobic processes control these variables, although this approach did not allow identifying unambiguously the dominant diagenetic carbon degradation pathway. During the rainy season, dilution led to significant decreases of salinity, TAlk and DIC in both mangrove creeks and adjacent main channels. In the Kiên Vàng mangrove creeks a distinct increase of pCO 2 and decrease of %O 2 were observed. The increase of TSM suggested enhanced inputs of organic matter probably from land surrounding the mangrove creeks, that could have led to higher benthic and water column heterotrophy. However, the flushing of water enriched in dissolved CO 2 originating from soil respiration and impoverished in O 2 could also have explained to some extent the patterns observed during the rainy season. Seasonal variations of pCO 2 were more pronounced in the Kiên Vàng mangrove creeks than in the Tam Giang mangrove creeks. The air-water CO 2 fluxes were 5 times higher during the rainy season than during the dry season in the Kiên Vàng mangrove creeks. In the Tam Giang mangrove creeks, the air-water CO 2 fluxes were similar during both seasons. The air-water CO 2 fluxes ranged from 27.1 mmol C m -2 d -1 to 141.5 mmol C m -2 d -1 during the dry season, and from 81.3 mmol m -2 d -1 to 154.7 mmol m -2 d -1 during the rainy season. These values are within the range of values previously reported in other mangrove creeks and confirm that the emission of CO 2 from waters surrounding mangrove forests are meaningful for the carbon budgets of mangrove forests.

Koné, Y. J.-M.; Borges, A. V.

2008-04-01

133

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

NASA Astrophysics Data System (ADS)

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.

Imgraben, Sarah; Dittmann, Sabine

2008-02-01

134

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

USGS Publications Warehouse

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.

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

2005-01-01

135

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

USGS Publications Warehouse

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.

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

2003-01-01

136

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

NASA Astrophysics Data System (ADS)

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.

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

2003-02-01

137

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

Microsoft Academic Search

Mangrove forests are characterized by distinctive tree-height gradientsthat reflect complex spatial, within-stand differences in environmentalfactors,including nutrient dynamics, salinity, and tidal inundation, across narrowgradients. To determine patterns of nutrient limitation and the effects ofnutrient availability on plant growth and within-stand nutrient dynamics, weused a factorial experiment with three nutrient treatment levels (control, N,P)and three zones along a tree-height gradient (fringe, transition,

Ilka C. Feller; Karen L. McKee; Dennis F. Whigham; John P. O'Neill

2003-01-01

138

Patterns of mangrove forest structure and soil nutrient dynamics along the Shark River estuary, Florida  

Microsoft Academic Search

The basal area and productivity of managrove wetlands are described in relation to selected soil properties to understand\\u000a the general pattern of optimum forest stature at the mouth of estuaries in the Everglades, such as the Shark River Slough,\\u000a Florida (U.S.). The basal area of mangroves decreases from 40.4 m2 ha?1 and 39.7 m2 ha?1 at two stations 1.8 km

Ronghua Chen; Robert R. Twilley

1999-01-01

139

Growth and yield in mangrove forests of the Federated States of Micronesia  

Microsoft Academic Search

Permanent mangrove forest plots in the Federated States of Micronesia (FSM) were installed in 1983 and remeasured during 1990–92. Species from slowest to fastest growing as determined by mean annual diameter increments over all size classes were Rhizophora apiculata (0.25 cm yr?1), Xylocarpus granatum (0.31 cm yr?1), Bruguiera gymnorrhiza (0.35 cm yr?1), Rhizophora mucronata (0.37 cm yr?1), and Sonneratia alba

Nora N Devoe; Thomas G Cole

1998-01-01

140

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

USGS Publications Warehouse

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.

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

2004-01-01

141

The keystone role of leaf-removing crabs in mangrove forests of North Brazil  

Microsoft Academic Search

Principle factors which influence mangroveleaf litter turnover, in particular therole of leaf-removing crabs, were evaluatedin a riverine mangrove site nearBragança (Pará, North Brazil). Ourspecial interest was focussed on the roleof the leaf-removing crab Ucidescordatus. Leaf litter fluxes between themangrove forest and the adjacent estuarywere investigated by estimating the biomassand fate of leaf litter material and propagules. Vegetation is dominated by

Dirk Schories; Audrey Barletta-Bergan; Mario Barletta; Uwe Krumme; Ulf Mehlig; Verena Rademaker

2003-01-01

142

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

Microsoft Academic Search

Simultaneous measurements of vertical accretion from artificial soilmarker horizons and soil elevation change from sedimentation-erosion table(SET) plots were used to evaluate the processes related to soil building infringe, basin, and overwash mangrove forests located in a low-energy lagoonwhich receives minor inputs of terrigenous sediments. Vertical accretionmeasures reflect the contribution of surficial sedimentation (sedimentdeposition and surface root growth). Measures of elevation

Donald R. Cahoon; James C. Lynch

1997-01-01

143

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

Microsoft Academic Search

Bacterial polyhydroxyalkanoates (PHAs) are perceived to be a suitable alternative to petrochemical plastics because they have\\u000a similar material properties, are environmentally degradable, and are produced from renewable resources. In this study, the\\u000a 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

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

2005-01-01

144

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

USGS Publications Warehouse

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 surface and subsurface processes and the procces controlling soil elevation differed among forest types. The mangrove ecosystem at Rookery Bay has remained stable as sea level has risen during the past 70 years. Yet, lead-210 accretion data suggest a substantial accretion deficit has occurred in the past century (accretion was 10-20 cm < sea-level rise from 1930 to 1990) in the fringe and island forests at Rookery Bay. In contrast, our measures of elevation change mostly equalled the estimates of sea-level rise and shallow subsidence. These data suggest that (1) vertical accretion in this system is driven by local sea-level rise and shallow subsidence, and (2) the mangrove forests are mostly keeping pace with sea-level rise. Thus, the vulnerability of this mangrove ecosystem to sea-level rise is best described in terms of an elevation deficit (elevation change minus sea-level rise) based on annual measures rather than an accretion deficit (accretion minus sea-level rise) based on decadal measures.

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

1997-01-01

145

Mangrove Action Project  

NSDL National Science Digital Library

This nonprofit organization provides information about the biology and ecology of mangrove species, the distribution of mangrove forests and importance of mangrove ecosystems to wildlife and people worldwide. Photos, slide show, current issues and links to related sites are provided. Threats to mangroves are described and sustainable alternatives, based on pilot projects, are presented. Appropriate for grades 8 and up.

146

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

USGS Publications Warehouse

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.

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

2009-01-01

147

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

PubMed

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

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

2014-01-01

148

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

USGS Publications Warehouse

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 ?mol (CO2) m-2 s-1 between March and May. Respiration (Rd) was highly variable (2.81 ± 2.41 ?mol (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 ?mol (CO2) m-2 s-1 and nighttime Rd by ~0.5 ?mol (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.

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

2010-01-01

149

Satellite-based estimates of light-use efficiency in a subtropical mangrove forest equipped with CO2 eddy covariance  

NASA Astrophysics Data System (ADS)

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 carbon dioxide 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 yr 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 night-time 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) increases 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 environmental conditions.

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

2012-11-01

150

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

PubMed

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. PMID:24747926

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

2014-06-01

151

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

NASA Astrophysics Data System (ADS)

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.

Calderon, Heyddy; Weeda, Ruben; Uhlenbrook, Stefan

2014-05-01

152

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

USGS Publications Warehouse

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).

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

2001-01-01

153

Tsunami damping by mangrove forest: a laboratory study using parameterized trees  

NASA Astrophysics Data System (ADS)

Tsunami attenuation by coastal vegetation was examined under laboratory conditions for mature mangroves Rhizophora sp. The developed novel tree parameterization concept, accounting for both bio-mechanical and structural tree properties, allowed to substitute the complex tree structure by a simplified tree model of identical hydraulic resistance. The most representative parameterized mangrove model was selected among the tested models with different frontal area and root density, based on hydraulic test results. The selected parameterized tree models were arranged in a forest model of different width and further tested systematically under varying incident tsunami conditions (solitary waves and tsunami bores). The damping performance of the forest models under these two flow regimes was compared in terms of wave height and force envelopes, wave transmission coefficient as well as drag and inertia coefficients. Unlike the previous studies, the results indicate a significant contribution of the foreshore topography to solitary wave energy reduction through wave breaking in comparison to that attributed to the forest itself. A similar rate of tsunami transmission (ca. 20%) was achieved for both flow conditions (solitary waves and tsunami bores) and the widest forest (75 m in prototype) investigated. Drag coefficient CD attributed to the solitary waves tends to be constant (CD = 1.5) over the investigated range of the Reynolds number.

Strusi?ska-Correia, A.; Husrin, S.; Oumeraci, H.

2013-02-01

154

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

NASA Astrophysics Data System (ADS)

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 ?g m-3 with production rate of 0.19 ?g m-2 s-1 (during January) to 4.29 ?g m-2 s-1 (during April) and dry deposition rate of 0.019 ?g m-2 s-1 (during January) to 13.21 ?g 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 ?m) and nucleation (dp < 0.4 ?m) modes compared to the accumulation mode (0.4 < dp < 2.0 ?m) 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 ?m. 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.

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

2006-12-01

155

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

USGS Publications Warehouse

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.

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

2003-01-01

156

Keystone species and mangrove forest dynamics: the influence of burrowing by crabs on soil nutrient status and forest productivity  

NASA Astrophysics Data System (ADS)

The density of the burrowing crab fauna in a mangrove forest was reduced, using pitfall traps, to test the hypothesis that decreased burrowing would lead to: (1) increased soil sulphide concentrations; (2) altered nutrient concentrations; and (3) decreased forest productivity and growth. Experiments were conducted in Rhizophora-dominated forests in north Queensland, Australia, over a 12-month period. Crabs were trapped and removed from the experimental plots during 1 week each month for a year. Soil chemical and forest growth parameters were measured at monthly intervals in the experimental and appropriate control plots. Over the course of the experiment, soil sulphide and ammonium concentrations increased to levels which were significantly higher in plots from which crabs were being removed in comparison to controls. No differences were observed for either phosphate or nitrate plus nitrite. Cumulative forest growth, as measured by stipule fall, was significantly less in removal plots than in controls. Additionally, trees in the removal plots had significantly less reproductive output than did trees in control plots. These results support the hypothesis that burrowing by crabs is an important process in Australian Rhizophora forests. It appears that burrowing affects soil aeration which in turn affects the productivity and reproductive output of Rhizophora. Knowledge of the ecology of grapsid crabs from other continents, however, is very limited. It remains to be seen if the roles played by grapsid crabs are as important elsewhere as in Australia. This is particularly true for the Caribbean region from which many of our paradigms concerning mangrove forest ecology were developed.

Smith, Thomas J.; Boto, Kevin G.; Frusher, Stewart D.; Giddins, Raymond L.

1991-11-01

157

Contribution of mangrove detritus to juvenile prawn nutrition: a dual stable isotope study in a Malaysian mangrove forest  

Microsoft Academic Search

Dual stable C and N ratio analyses of primary producers and prawns have clarified the important role of mangrove detritus\\u000a as the primary food source of juvenile prawns inhabiting the upper estuaries of the Matang mangrove swamp in Malaysia. The\\u000a contribution of mangrove carbon to prawn tissues, as high as 84%, decreased in the offshore direction, as the contribution\\u000a by

V. C. Chong; C. B. Low; T. Ichikawa

2001-01-01

158

The influence of stand age on benthic decomposition and recycling of organic matter in managed mangrove forests of Malaysia  

Microsoft Academic Search

Decomposition of sediment organic matter was examined in relation to forest age in 2-, 15- and 60-year old, managed Rhizophora apiculata (Blume) stands in the Matang Mangrove Forest Reserve of peninsular Malaysia. Rates of O2 consumption (range: 11.5–21.4 mmolm?2d?1) and CO2 production (range: 8.9–20.9 mmolm?2d?1) were equivalent among the forests indicating that early diagenesis is not linked to stand age

D. M Alongi; A Sasekumar; F Tirendi; P Dixon

1998-01-01

159

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

PubMed Central

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 source of income. Most of the villagers (85.83%) often depend on mangroves for subsistence needs and for them there is no substitute for mangrove wood. Therefore, more efforts should be undertaken at the national level to implement conservation, management and sustainable use of these coastal forests.

2009-01-01

160

Spatial and Temporal Patterns of Soil Organic Carbon in Mangrove Forest Ecosystems (Invited)  

NASA Astrophysics Data System (ADS)

Wetlands are recognized as potentially important carbon sinks, but few studies have focused on tropical and sub-tropical systems that accumulate organic carbon. Soil organic carbon (SOC) density was analyzed in multiple mangrove forests, representing 30 geographic locations and six forest types (total of 230 study plots overall). SOC density varied from 0.002 to 0.1 g cm-3, with an overall average of 0.019 and 0.058 g cm-3 in mineral and organic soils, respectively. Sites spanned a latitudinal range from 37° S to 29° N, and carbon density was correlated with average annual temperature. However, high variation in SOC density within latitude indicated additional influences. At a regional scale, SOC density varied with forest type and generally increased with hydrologic energy. At a site in Panama, SOC density varied spatially with soil pore space, which influenced bulk density and soil temperature—indicating an influence of compaction and/or degree of decomposition. Carbon sequestration rates estimated from surface accretion of organic C were similar in organic (216 g C m-2 yr-1) and mineral (145 g C m-2 yr-1) soil types, but varied across geographic locations (41 to 591 g C m-2 yr-1). Subsurface inputs of carbon, which were estimated using measured rates of root matter accumulation and root carbon content, averaged 121 g m-2 yr-1, but exceeded 400 g m-2 yr-1 at several sites. Depths of mangrove peat varied across sites from < 1 m to over 10 m, indicating the potentially large carbon stores that can develop under certain conditions. Rates of carbon accretion at a site in Belize have varied from 90 to 300 g C m-2 yr-1 over 8000 yr. These patterns indicate spatial and temporal variability in SOC and suggest multiple controls on rates of carbon accumulation in mangrove ecosystems.

McKee, K. L.

2010-12-01

161

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

USGS Publications Warehouse

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.

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

2010-01-01

162

Biosphere-atmosphere exchange of NOx in the tropical mangrove forest  

NASA Astrophysics Data System (ADS)

Biosphere-atmosphere exchange of NOx at the Sundarban mangrove forest along the northeast coast of the Bay of Bengal, India, showed uptake rates of -0.84 to -1.63 ng N m-2 s-1 during the day and both uptake and emission rates of -0.36 to 5.19 ng N m-2 s-1 during the night from September to February. However, during the period from March to August, NOx emission ranged between 0.34 and 2.13 ng N m-2 s-1 and 0.88 and 3.26 ng N m-2 s-1 in daytime and nighttime, respectively. During the postmonsoon period, NOx uptake could be attributed to mangrove stomatal activity during the day. Mangroves absorbed nitrogen from both the soil and the atmosphere. Seasonal and diurnal variability of NOx and O3 is partly due to plant growth in the postmonsoon period. In addition to the NOx-O3 photochemical cycle, stomatal uptake of NOx could also be an important process for keeping a low-ozone state at the land-ocean boundary of the northeast coast of the Bay of Bengal.

Ganguly, D.; Dey, M.; Sen, S.; Jana, T. K.

2009-12-01

163

Mosquitoes of the mangrove forests of India: part four--Coringa, Andhra Pradesh.  

PubMed

Mosquitoes of 12 species belonging to 5 subgenera and 9 genera--Aedes, Anopheles, Culex, Diceromyia, Lorrainea, Rhinoskusea, Stegomyia, Toxorhynchites, and Verrallina--were recorded in the Coringa mangrove forest in Andhra Pradesh, India. Tree holes, crab holes, and swamp pools constituted the larval habitats with Lo. fumida being predominant in tree holes. Adults were found resting in tree holes, tree trunks, root bases, and in crab holes. Species involved in daytime feeding on humans were Ae. cancricomes, Cx. sitiens, Lo. fumida, Rh. wardi, and Ve. lugubris. PMID:17304921

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

2006-12-01

164

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

USGS Publications Warehouse

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.

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

2003-01-01

165

Mosquitoes of the mangrove forests of India: Part 1--Bhitarkanika, Orissa.  

PubMed

In this first paper of a series on mosquitoes of the mangrove forests of India, details of mosquito species recorded in Bhitarkanika, Orissa, are presented. Forty-three species of mosquitoes belonging to 21 subgenera and 13 genera, Aedes, Anopheles, Armigeres, Coquillettidia, Culex, Ficalbia, Heizmannia, Lutzia, Mansonia, Ochlerotatus, Toxorhynchites, Uranotaenia, and Verrallina, were recorded. Predominant larval habitat was the tree holes, from which 15 species were taken. Adults were mostly found resting in crab holes, tree holes, and hoof prints in the forest area and on walls in the guesthouse area. About 14 species were caught in light traps, while 19 species landed on humans for feeding. Ae. franciscoi and Oc. feegradei are 2 new country records for India. Ae. cancricomes and Cx. perplexus, known only from Andaman Islands of India, are new records for mainland India. PMID:16033113

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

2005-06-01

166

Leaf litter removal by the snail Terebralia palustris (Linnaeus) and sesarmid crabs in an East African mangrove forest (Gazi Bay, Kenya)  

Microsoft Academic Search

Quantitative data on leaf litter removal activity of macrozoobenthic organisms in the mangrove forests of East Africa are virtually non-existent. In the present study, litter removal activity was determined in two contrasting types of mangrove stands in Gazi Bay (Kenya). In the relatively elevated Ceriops tagal vegetation, which is only flooded during spring tides, the detritivorous snail Terebralia palustris (Linnaeus)

F. J Slim; M. A. Hemminga; C. Ochieng; N. T Jannink; E Cocheret de la Morinière; G. Van der Velde

1997-01-01

167

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

NASA Astrophysics Data System (ADS)

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. This is explained by the relative density difference in the OC and marine carbonate as the lower density organic matter is transported a greater distance inland. While an increase in tropical storm activity might produce more damage and loss of mangrove forest along open water (e.g., Gulf of Mexico), our findings suggest that inland sites may benefit from the storm surge material. In addition, not all of the remobilized OC is oxidized as a portion is transferred inland and subsequently buried, therefore limiting CO2 release to the atmosphere.

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

2013-05-01

168

Nitrogen fixation (acetylene reduction) associated with communities of heterocystous and non-heterocystous blue-green algae in mangrove forests of Sinai  

Microsoft Academic Search

High rates of nitrogen fixation (acetylene reduction) are associated with communities of heterocystous and non-heterocystous blue-green algae, which are widespread and abundant in the coastal mangrove forests of the Sinai Peninsula.

M. Potts; Heinz Steinitz

1979-01-01

169

Gas-phase carbon exchange between mangrove forests and the atmosphere  

NASA Astrophysics Data System (ADS)

Mangrove ecosystems are believed to be highly productive, storing carbon at rates as high as or higher than terrestrial tropical rainforests. Their high productivity is reflected in the high levels of organic carbon stored within, and exported from, these ecosystems. This includes so-called blue carbon - carbon of terrestrial origin sequestered in coastal margins. Despite their potential importance, significant knowledge gaps exist both in the magnitudes of the components of mangrove carbon balance, and the factors controlling them. These gaps result from the lack of primary datasets, which is itself a consequence of the complex nature of mangrove ecosystems, and of the difficult working conditions found there. Here, we report on a study designed to elucidate some of the environmental controls on the exchange of CO2 and CH4 to and from intact mangrove ecosystems in East Africa. Gazi Bay (4° 25'S, 39° 30'E), south of Mombasa, Kenya, encompasses around 600 ha of mangrove forest, including partially and severely degraded stands as well as restored areas. The area contains all 10 species of mangrove found in East Africa, including mono-specific areas of the two most common species, Avicennia marina and Rhizophora mucronata, sufficiently extensive for robust eddy covariance (EC) measurements. During 2012, open path EC measurements were made at both Avicennia marina and Rhizophora mucronata sites throughout a spring/neap tidal cycle. Flux data were fitted to a simple model describing the ecosystem level response to environmental variables. Stands of both species exhibited higher maximum net ecosystem uptake, but lower apparent quantum efficiency and lower dark respiration when inundated by high tides. Maximum net ecosystem uptake was higher in Rhizophora (12.8 (dry) - 16.5 (wet) ?mol m-2 s-1) than in Avicennia (5.1 (dry) - 5.9 (wet) ?mol m-2 s-1). Apparent quantum efficiency was twice as high in Rhizophora (0.09 (wet) - 0.12 (dry) mol mol-1) than in Avicennia (0.03 (wet) - 0.06 (dry) mol mol-1). Dark respiration rates were broadly similar when the tide was out (8.3 ?mol m-2 s-1 (Rhizophora), 7.3 ?mol m-2 s-1 (Avicennia)), but high tide reduced respiration much more in Avicennia (0.5 ?mol m-2 s-1) than in Rhizophora (7.5 ?mol m-2 s-1). Methane exchange between the Rhizophora ecosystem and the atmosphere was small and dependant on tidal state, varying between a methane consumption of around 0.2 mg (C) m-2 hr-1 at low and incoming tide to a methane production of around 2.5 mg (C) m-2 hr-1 during outgoing tides. The Avicennia ecosystem was consistently a small consumer of methane (ca. 0.2 mg (C) m-2 hr-1).

Rayment, Mark

2013-04-01

170

Process Models for Monitoring Forest Health.  

National Technical Information Service (NTIS)

Process models have been suggested as a basis for forest monitoring. A process model-based system yields biologically interpretable data according to a particular hypothesis of forest biology. But there is a potential tradeoff between the need for practic...

K. H. Ritters

1987-01-01

171

Plant biomass and nutrient flux in a managed mangrove forest in Malaysia  

Microsoft Academic Search

This paper summarizes previously reported and new data. Data on biomass and nutrient content in different components of the mangrove trees are presented and estimates of the flux of these are attempted. As a first step to determining the quantitative relationship between the export of material and the areal extent of mangroves, the biomass and nutrients contained in the mangrove

Wooi-Khoon Gong; Jin-Eong Ong

1990-01-01

172

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)

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.

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

2008-06-01

173

Biomass and litterfall of Ceriops tagal and Rhizophora mucronata in the mangrove forest of Gazi Bay, Kenya  

Microsoft Academic Search

Biomass and (leaf) litter production of stands of Rhizophora mucronata and Ceriops tagal were assessed in an East African mangrove forest. Inundation frequency of the R. mucronata stand was twice a day (on average 575 min day(-1)), whereas the C. tagal stand was inundated only during spring tides (on average 116 min day(-1)). The highest above-ground biomass (24.9 +\\/- 4.0

Slim J. F; Gwada M. P; M. Kodjo; M. A. Hemminga

1996-01-01

174

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

SciTech Connect

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.

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

1987-01-01

175

Discrimination of mangrove forests and characterization of adjoining land cover classes using temporal C-band Synthetic Aperture Radar data: A case study of Sundarbans  

NASA Astrophysics Data System (ADS)

C-band dual polarization (HH, HV) Synthetic Aperture Radar (SAR) data from Radarsat-2 were used to discriminate and characterize mangrove forests of the Sundarbans. Multi-temporal data acquired during winter and rainy seasons were analysed for the segregation of mangrove forest area. A decision rule based classification involving combination of three-date HH (range -11 to -2 dB) with single-date cross-polarization ratio (2-8) was applied on the datasets for discriminating mangrove forests from other land cover classes. Application of textural measures (entropy and angular second moment) in the aforesaid decision rule based classification produced three broad homogeneous mangrove classes. The area covered by the most homogeneous class increased from January to March and decreased from July to September, and correlated well to the change in the phenological status of the mangroves. Extent of homogeneous areas was more in the eastern region of the Sundarbans than that of the central and western side. Thus, the study revealed that textural measures combined with multi-temporal HH backscatter and single-date cross-polarization ratio in a decision rule classification could be satisfactorily used for characterization of the mangrove forests.

Kumar, Tanumi; Patnaik, C.

2013-08-01

176

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

NASA Astrophysics Data System (ADS)

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 analyzed for major ions (e.g, Cl-, SO42-, Na2+, Mg2+, K+, and Ca2+) and nutrients (e.g., total organic carbon, N and P). The spectral responses of each of the mangrove species were collected in-situ within a few days of the water sampling. Initial results illustrate good correlations (R2>0.65; P<0.05) between various spectra-derived biophysical indices (e.g., EVI, NDVI) and porewater chloride concentrations. Other correlations demonstrate complex relationships between total N and P concentrations and site-specific mangrove spectra, suggesting physiological differences of nutrient uptake induced by salinity-related stress. The findings suggest the potential for upscaling these relationships using airborne and satellite hyperspectral imagery (e.g., AVIRIS, Hyperion) in order to monitor salt-water intrusion remotely on a regional scale. Further investigations with this research could provide insight to water and carbon flux dynamics within the Everglades and similar coastal mangrove ecosystems throughout the world.

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

2011-12-01

177

Forest fire monitoring with multiple small UAVs  

Microsoft Academic Search

Frequent updates concerning the progress of a forest fire are essential for effective and safe fire fighting. Since a forest fire is typically inaccessible by ground vehicles due to mountainous terrain, small unmanned air vehicles (UAVs) are emerging as a promising means of monitoring large forest fires. We present an effective UAV path planning algorithm utilizing infrared images that are

David W. Casbeer; Randal W. Beard; T. W. McLain; Sai-Ming Li; R. K. Mehra

2005-01-01

178

Forest Health Monitoring: A National Strategic Plan.  

National Technical Information Service (NTIS)

Forest Health Monitoring (FHM) is a national program designed to determine the status, changes, and trends in indicators of forest health. From its inception in 1990 in the New England states, the FHM program has expanded to encompass all the forested lan...

2003-01-01

179

FOREST HEALTH MONITORING - 1991 STATISTICAL SUMMARY  

EPA Science Inventory

This is a statistical summary of forest measurement data from the Forest Health Monitoring Network. here are now 925 plots in the FHM national network, of which 628 plots are forested. sing a probability sampling design, the installed plots are located systematically throughout t...

180

Litter dynamics in riverine mangrove forests in the Guayas River estuary, Ecuador  

Microsoft Academic Search

The hypothesis that rates of litter turnover in mangroves are controlled by local geophysical processes such as tides has\\u000a been studied at sites with mostly small tides (<1?m) and minor crab consumption of leaf litter. Our study describes litter\\u000a dynamics of three riverine mangrove sites (M1, M2, M3), inhabited by the mangrove crab Ucides occidentalis, located in a macrotidal (>3?m)

Robert R. Twilley; Mireya Pozo; Victor H. Garcia; Victor H. Rivera-Monroy; Ramon Zambrano; Alejandro Bodero

1997-01-01

181

Implication of organic matter on arsenic and antimony sequestration in sediment: evidence from Sundarban mangrove forest, India.  

PubMed

This study reports the measurement of stability constants for the interaction of As (V and III) and Sb (V and III) with humic substances extracted from aquatic sediments of the Sundarban mangrove forest ecosystem. It was observed that As and Sb formed a slightly more stable association with fulvic acid (FA) than with its humic acid (HA) counterpart. Quenching of fluorescence at increasing As (III and V) or Sb (III and V): FA or HA ratios was obtained that ideally correspond to a 1:1 complexation model. Quite strong complexation of As and Sb by FA and HA occurs at neutral pH, indicating that HA and FA probably markedly affect the mobility of As and Sb in the mangrove environment. PMID:23299951

Mandal, S K; Ray, R; Chowdhury, C; Majumder, N; Jana, T K

2013-04-01

182

Bacillus amyloliquefaciens: a mosquitocidal bacterium from mangrove forests of Andaman & Nicobar islands, India.  

PubMed

Samples collected from the mangrove forests of Andaman & Nicobar islands yielded a mosquitocidal bacterium, whose extracellular metabolite(s) exhibited mosquito larvicidal and pupicidal activity. The bacterium was isolated using standard microbiological methods and identified using classical biochemical tests and rpoB gene sequences. The mosquitocidal bacterium was identified as Bacillus amyloliquefaciens. Mosquitocidal metabolite(s) was separated from the culture supernatant of the bacterium and its efficacy against the larval and pupal stages of different species of mosquitoes was determined in terms of LC(50) and LC(90). Mosquito larvicidal activity in terms of LC(50) against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was respectively, 26.4?g, 22.2?g and 20.5?g/ml and its pupicidal activity was 4.4?g, 8.2?g and 14.5?g/ml respectively. The mosquitocidal metabolite(s) was found to be a biosurfactant. This is the first report of the mosquitocidal activity of B. amyloliquefaciens and it is a new weapon which can be added to the array of microbial agents for use against mosquitoes. PMID:21810402

Geetha, I; Manonmani, A M; Prabakaran, G

2011-12-01

183

Sedimentation within and among mangrove forests along a gradient of geomorphological settings  

NASA Astrophysics Data System (ADS)

Coastal wetlands provide important ecological services to the coastal zone, one of which is sediment retention. In this study we investigated sediment retention across a range of geomorphological settings and across vegetation zones comprising coastal wetlands. We selected six coastal wetlands dominated by mangroves over a gradient from riverine to tidal settings in Southeast Queensland, Australia. Each site was comprised of three distinct vegetation communities distributed as parallel zones to the coast line: seaward fringe mangroves, landward scrub mangroves and saltmarsh/ cyanobacteria mat of the high intertidal zone. We measured suspended sediment retention and sedimentation rates. Additionally, in order to assess the origin of sediment transported and deposited in the mangroves, glomalin, a novel terrestrial soil carbon tracer, was used. Our results show a mean average sedimentation of 0.64 ± 0.01 mg cm -2 spring tide -1, which was variable within sites, regardless of geomorphological setting. However, geomorphological setting influenced spatial patterns of sediment deposition. Riverine mangroves had a more homogeneous distribution of sediments across the intertidal zone than tidal mangroves, where most sedimentation occurred in the fringe zone. Overall, the fringe zone retained the majority of sediment entering the coastal wetland during a tidal cycle with 0.90 ± 0.22 mg cm -2 spring tide -1, accounting for 52.5 ± 12.5% of the total sedimentation. The presence of glomalin in suspended sediments, and thus the relative importance of terrigenous sediment, was strongly influenced by geomorphological setting, with riverine mangroves receiving more glomalin in suspended solids than tidal mangroves. Glomalin was also differentially deposited within the vegetation zones at different geomorphological settings: primarily at the fringe zone of tidal mangroves and within the scrub zone of riverine mangroves. The differences we observed in the spatial distribution of sedimentation and the difference in the origin of the sediment deposited in riverine and tidal mangroves are likely to have an impact on ecological processes.

Adame, María Fernanda; Neil, David; Wright, Sara F.; Lovelock, Catherine E.

2010-01-01

184

Remote Sensing of Mangrove Change Along the Tanzania Coast  

Microsoft Academic Search

This article contributes to the understanding of the changes in distribution and total area of mangrove forests along the mainland Tanzania coast over the past decade. Mangroves are recognized as critical coastal habitat requiring protection and special attention. The Tanzania coastline forms a suitable habitat for establishment of mangrove forests. Mangrove forests are distributed from Tanga in the north to

Yeqiao Wang; Gregory Bonynge; Jarunee Nugranad; Michael Traber; Amani Ngusaru; James Tobey; Lynne Hale; Robert Bowen; Vedast Makota

2003-01-01

185

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)

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.

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

2008-12-01

186

The distribution of acid-volatile sulfide and simultaneously extracted metals in sediments from a mangrove forest and adjacent mudflat in Zhangjiang Estuary, China.  

PubMed

The distribution of acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) were studied in sediments collected from mangrove forest, forest fringe and adjacent mudflat in the Zhangjiang Estuary, China. The aim was to examine the spatial distribution of AVS and SEM in sediments of the Estuary and determine the influence of mangrove trees on AVS and SEM concentrations in the sediments. The results indicated that AVS concentrations in forest sediments were significantly lower than those in mudflat sediments. There was a significant positive correlation between AVS values and moisture contents in forest sediments, while LOI played an important role in AVS concentrations of mudflat sediments. In the forest sediment core, the peak value of AVS appeared deeper in the sediment profile compared to it appeared in the mudflat core. The distribution of SEM showed different trends from that of AVS, and potential toxicity existed in the upriver forest sediments. PMID:20434182

Jingchun, Liu; Chongling, Yan; Spencer, Kate L; Ruifeng, Zhang; Haoliang, Lu

2010-08-01

187

Litter production and litter elemental composition in two rehabilitated Kandelia obovata mangrove forests in Jiulongjiang Estuary, China.  

PubMed

Spatial and seasonal variations in litter production and C, N, and P concentrations were compared between the 24 and 48 year old Kandelia obovata mangrove forests in the Jiulongjiang estuary, China. The 24 yr forest had significantly higher production of total, leaf and branch litter, but lower flower and fruit litter than the 48 yr forest. Total, leaf and branch litter production were significantly positively correlated to monthly temperature and rainfall. Spatial patterns of litter production among the inner, mid and outer zones in the same forest were similar to those of tree heights. C, N and P concentrations of leaf litter showed significant seasonality but varied little among these three forest zones. C/N and N/P ratios of leaf litter were significantly lower for the 24 yr forest than those for the 48 yr forest. During the entire sampling year, total litter of the 24 and 48 yr forests contained 590.31 and 437.31 g C m(-2) yr(-1), 8.46 and 5.47 g N m(-2) yr(-1), 1.92 and 1.16 g P m(-2) yr(-1), respectively. PMID:23164398

Ye, Y; Chen, Y P; Chen, G C

2013-02-01

188

Primary producers sustaining macro-invertebrate communities in intertidal mangrove forests  

Microsoft Academic Search

In contrast to the large number of studies on the trophic significance of mangrove primary production to the aquatic foodweb, there have been few attempts to provide an overview of the relative importance of different primary carbon sources to invertebrates in the intertidal mangrove habitats. We determined carbon and nitrogen stable isotope ratios (ཉC, ཋN) in sediments, primary producers, and

S. Bouillon; N. Koedam; A. V. Raman; F. Dehairs

2002-01-01

189

Timber Volumes in the Mangrove Forests of Pohnpei, Federated States of Micronesia.  

National Technical Information Service (NTIS)

The mangrove resource is of great value to Pohnpei. A volumetric inventory of 4855 ha of mangroves on the island was conducted in 1984. Two size strata were sampled: trees with diameters at breast height (d.b.h.) of 30 cm or greater, and smaller trees wit...

E. Q. P. Petteys S. Peter R. Rugg T. G. Cole

1986-01-01

190

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

PubMed Central

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.

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

2012-01-01

191

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

PubMed Central

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 management of the mangrove ecosystems through afforestation (in large impacted areas), selective removal of senescent tree stems and branches (in little damage stands), regulating sand extraction and housing activities, and creating awareness and law enforcement.

2011-01-01

192

Characterizing spatial and seasonal variability of carbon dioxide and water vapour fluxes above a tropical mixed mangrove forest canopy, India  

NASA Astrophysics Data System (ADS)

The above canopy carbon dioxide and water vapour fluxes were measured by micrometeorological gradient technique at three distant stations, within the world's largest mangrove ecosystem of Sundarban (Indian part), between April 2011 and March 2012. Quadrat analysis revealed that all the three study sites are characterized by a strong heterogeneity in the mangrove vegetation cover. At day time the forest was a sink for CO2, but its magnitude varied significantly from -0.39 to -1.33 mg m - 2 s - 1. The station named Jharkhali showed maximum annual fluxes followed by Henry Island and Bonnie Camp. Day time fluxes were higher during March and October, while in August and January the magnitudes were comparatively lower. The seasonal variation followed the same trend in all the sites. The spatial variation of CO2 flux above the canopy was mainly explained by the canopy density and photosynthetic efficiency of the mangrove species. The CO2 sink strength of the mangrove cover in different stations varied in the same way with the CO2 uptake potential of the species diversity in the respective sites. The relationship between the magnitude of day time CO2 uptake by the canopy and photosynthetic photon flux was defined by a non-linear exponential curve (R2 ranging from 0.51 to 0.60). Water vapour fluxes varied between 1.4 and 69.5 mg m - 2 s - 1. There were significant differences in magnitude between day and night time water vapour fluxes, but no spatial variation was observed.

Chanda, Abhra; Akhand, Anirban; Manna, Sudip; Dutta, Sachinandan; Hazra, Sugata; Das, Indrani; Dadhwal, V. K.

2013-04-01

193

Regeneration of Rhizophora mucronata (Lamk.) in degraded mangrove forest: Lessons from point pattern analyses of local tree interactions  

NASA Astrophysics Data System (ADS)

Spatial structural patterns emerging from local tree interactions influence growth, mortality and regeneration processes in forest ecosystems, and decoding them enhance the understanding of ecological mechanisms affecting forest regeneration. Point-Patterns analysis was applied for the very first time to mangrove ecology to explore the spatial structure of Rhizophora mucronata regeneration in a disturbed mangrove forest; and the pattern of associations of juvenile-adult trees. R. mucronata trees were mapped in plots of 50 m × 10 m located at the seaward, central and landward edge along 50 m wide transect in the forest, and the mapped patterns were analysed with pair correlation and mark-connection functions. The population density of R. mucronata differed along the tidal gradient with the highest density in the central region, and the least near the shoreline. The study revealed that short distance propagule dispersal, resulting in the establishment of juveniles in closed distance to the mother trees, might not be the driving force for distribution of this species. The spatial structural pattern of R. mucronata population along tidal gradient showed a characteristic spatial aggregation at small scale, but randomly distributed as the distances become larger. There was a distinct spatial segregation between recruits and adult trees, and hence spatially independent. Though, adult-adult trees associations did not show a clear spatial segregation pattern; the recruit-recruit species associations exhibited significant clustering in space. Although habitat heterogeneity might be responsible for the local scale aggregation in this population, the effect of plant-plant conspecific interactions is more probable to inform the long-term structure and dynamics of the population of R. mucronata, and ditto for the entire forest.

Olagoke, Adewole O.; Bosire, Jared O.; Berger, Uta

2013-07-01

194

Managing mangroves in Bangladesh: A strategy analysis  

Microsoft Academic Search

Bangladesh, favoured by a tropical climate, houses the world’s largest stretch of mangroves forests (Sundarbans Reserved Forest)\\u000a and plantations. Around half of the forests of the country occur in the coastal zone. People extract various goods and services\\u000a from the mangroves. Nevertheless the mangrove forests are depleting. Although the extent of the Sundarbans forest has not\\u000a changed much, its decline

M. S. Iftekhar; M. R. Islam

2004-01-01

195

Dispersal, establishment and survival of Ceriops tagal propagules in a north Australian mangrove forest  

Microsoft Academic Search

Studies of the ecology of mangroves show that a wide variety of factors, including salinity, desiccation, disturbance, competition\\u000a and predation, may affect the distribution and abundance of species. Field studies were done to examine the relative importance\\u000a of several of these factors in the establishment and early survival of Ceriops tagal, a species common in mid-to high-shore regions of mangrove

K. A. McGuinness

1996-01-01

196

Changes in mangrove forest soils: a comparison between cultured and naturally inundated conditions  

Microsoft Academic Search

A study was carried out in three shrimp farms in a natural mangrove area at the southeastern part of Bangladesh that dealt\\u000a mainly with the changes in mangrove soil characteristics in both cultured and naturally inundated conditions. Some noticeable\\u000a changes were observed in case of soil pH, sulfate sulfur(SO4-S) and extractable aluminium (Al) where, soil pH has shown a negative

M. A. Kabir Chowdhury

2001-01-01

197

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

NASA Astrophysics Data System (ADS)

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 ?mol m-2 s-1 and -22 ?mol 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 ?mol m-2 s-1 at a reference temperature of 20 oC during low tide periods. Nightime Re at 20 oC increased by an average of 0.6 ?mol m-2 s-1 during low tide periods. Temperature response functions suggest the higher soil temperature after the storm resulted in an average increase in Rs of 1 to 2 ?mol m-2 s-1. This is correlated with a general decline in peat surface elevations, suggesting significant carbon loss from the soil has occurred through carbon efflux and dissolved fluxes to the tide. However, the rate of changes in peat surface elevations has decreased over the last year with canopy closure, suggesting the soil and overall ecosystem carbon balance are approaching a new dynamic equilibrium following the storm.

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

2009-12-01

198

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)

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 trees could be modeled as a combination of tapered geometric surfaces called frustums. The volume of the various geometric frustums can be estimated using specific mathematical formulas. We compared our TLS-derived tree volume/AGB versus published allometric equation-derived tree volume/AGB for our mangrove sites. Preliminary results yielded a good agreement between the TLS-derived and the allometric-derived biomass measurements, with TLS slightly underestimating it. In addition, we compared hand-measured tree attributes vs. TLS-measured tree attributes. Preliminary results showed that DBH can be precisely estimated with TLS. In the other hand, tree height can be estimated in places where there is low vegetation density due to point cloud occlusion and shadowing. We suggest that TLS shows potential to fill the gap between traditional forestry measurements and airborne LiDAR for forestry applications.

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

2012-12-01

199

A post-classifier for mangrove mapping using ecological data  

NASA Astrophysics Data System (ADS)

A global decline in tropical mangrove forests is one of the most serious problems of the world's coastal ecosystems. This problem results in an increasing demand of detailed mangrove maps at the species level for monitoring mangrove ecosystems and their diversity. Consequently, this research is the first to investigate the unexplored potential of exploiting mangrove-environment relationships for improving the quality of the final mangrove map at the species level. The relationships between mangroves and the surrounding environmental gradient were incorporated into the mapping process via a typical Bayesian probability model. The Bayesian model functioned as a post-classifier to improve the quality of an already-produced mangrove map. The environmental gradient in use was a GIS layer of soil pH data. Despite the remaining confusion between R. mucronata and S. caseolaris, it was found that the investment of the integration of soil pH into the mapping process paid off as it significantly increased the mapping accuracy from 76.04% to 88.21%. It is anticipated that the methodology presented in this study may be used as a guideline for producing mangrove maps at a finer level.

Vaiphasa, Chaichoke; Skidmore, Andrew K.; de Boer, Willem F.

200

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)

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.

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

2007-09-01

201

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

NASA Astrophysics Data System (ADS)

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 ?13C-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 ?13C-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 ?13C-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 enables us to analyze up to 24 samples per day, allowing for a more rapid sample throughput than alternative ?13C-DOC analytical methods including WCO-IRMS. This method was applied to marine samples collected from Shark River (SR) located on the western edge of Everglades National Park. DOC concentrations for water in this estuary typically fall between 2 and 18 ppm, with salinities that range from fresh to marine (~30) where SR empties into the Gulf of Mexico. Water samples were collected from Florida Coastal Everglades LTER sampling sites located in SR and analyzed for DOC concentration and ?13C-DOC composition. DOC concentration ranged from 6 to 15 ppm and ?13C-DOC values were between -32 and -27.8‰. These results are also compared to the ?13C-DIC data from the same samples. These results indicate that mangroves are the major contributor to the DOC pool in SR. The new WCO-CRDS method will enable us to continue analysis of DOC and ?13C-DOC in marine waters, such as the Shark River estuary, to better understand C dynamics. With this approach will be able to build a dataset to help identify spatial and temporal variations in and controls on DOC and ?13C-DOC in these coastal marine settings, which are an important interface between atmospheric and oceanic carbon reservoirs.

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

2012-12-01

202

Participatory monitoring of changes in coastal and marine biodiversity  

Microsoft Academic Search

This study reports results obtained from participatory monitoring conducted in Tanzania in two types of keystone ecosystems, mangrove forests and coral reefs. The report also analyses participatory monitoring as an effective tool in environmental conservation and management. Participatory monitoring data collected from three mangrove areas subjected to different levels of human impacts, low, moderate and high, clearly indicated the effects

Greg M. Wagner

203

National Satellite Forest Monitoring systems for REDD+  

NASA Astrophysics Data System (ADS)

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 countries to adapt it to country needs and the training on the TerraAmazon system is a tool to enhance existing capacity on carbon monitoring systems. The support with the National Forest Monitoring System will allow these countries to follow all actions related to the implementation of its national REDD+ policies and measures. The monitoring system will work as a platform to obtain information on their REDD+ results and actions, related directly or indirectly to national REDD+ strategies and may also include actions unrelated to carbon assessment, such as forest law enforcement. With the technical assistance of FAO, INPE and other stakeholders, the countries will set up an autonomous operational forest monitoring system. An initial version and the methodologies of the system for DRC and PNG has been launched in Durban, South Africa during COP 17 and in 2012 Paraguay, Viet Nam and Zambia will be launched in Doha, Qatar at COP 18. The access to high-quality satellite data for these countries is crucial for the set-up.

Jonckheere, I. G.

2012-12-01

204

Mosquitoes of the mangrove forests of India: part 5--Chorao, Goa, and Vikhroli, Maharashtra.  

PubMed

Mosquitoes of 14 species belonging to 9 subgenera and 9 genera were recorded in Chorao mangroves of Goa, and 12 species belonging to 9 subgenera and 7 genera in the mangroves of Vikhroli, Maharashtra, in India. Genera recorded were Aedes, Anopheles, Armigeres, Culex, Mansonia, Ochlerotatus, Orthopodomyia, Toxorhynchites, Uranotaenia, and Verrallina. Species common to both the mangroves were Ae. albopictus, Ae. novalbopictus, An. subpictus, Cx. sitiens, Oc. wardi, Ur. atra, and Ve. lugubris. Tree holes, crab holes, and swamp pools were the common larval habitats in Chorao, but tree holes were absent in Vikhroli. Adults of Ae. albopictus, Ae. novalbopictus, Ar. subalbatus, Cx. gelidus Cx. sitiens, Ma. indiana, Ur. atra, and Ve. lugubris were found landing on humans. Aedes novalbopictus, Oc. wardi, and Or. anopheloides are new records for the state of Goa. PMID:17847838

Rajavel, A R; Natarajan, R; Vaidyanathan, K; Soniya, V P

2007-06-01

205

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

USGS Publications Warehouse

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.

McKee, K. L.

2001-01-01

206

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)

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 ?) 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. On small ledges of a granitic body at 120 m from the shore fragmented and complete shells were deposited at different elevations of up to 4 m. This implies a run up height of at least 4 m above sea level at this distance from the shore. Our study presents the mapping of the tsunamigenic sand lobes, their grain size distribution and petrographic variations of their components compared to the mangrove soil. The difference in the grain size and amount of organic material of the mangrove soil compared to the sand lobes indicate that the coarser material was entrained from outside of the mangrove forest by the tsunami. The similarity of the grain size distributions of the sediment of the sand lobes and of a reference beach/intertidal sample suggests the lagoon between the mangrove forest and the causeway as the probable sediment source area. The fact that the mangrove forest is surrounded by granitic hills and the appearance of the carbonate sandstone debris mostly on the surface of the sand sheets supports this assumption.

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

2012-12-01

207

The distribution and influence of heavy metals in mangrove forests of the Tamshui Estuary in Taiwan  

Microsoft Academic Search

The Tamshui estuary area is one of the few locations in Taiwan where mangroves are still growing. Heavy metals are generally carried by the water of the Tamshui river and accumulate in the estuary soil. Their accumulation is closely related to the frequency and duration of tidal flood. The concentration of heavy metals in Kandelia candel showed a sequential decline

Chih-Yu Chiu; Chang-Hung Chou

1991-01-01

208

Monitoring Change in Temperate Coniferous Forest Ecosystems  

NASA Technical Reports Server (NTRS)

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 monitor forest change with remote sensing. There were no new inventions that resulted from this grant.

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

2004-01-01

209

Hydraulic Conductivity of Riparian Mangrove Forest Peat Adjacent to the Harney River, Everglades National Park: A Comparative Field Study of Field Saturated and Saturated Hydraulic Conductivity Methods.  

NASA Astrophysics Data System (ADS)

The Shark-Harney river estuary is located in the southwest region of Everglades National Park and is the principle outflow for the freshwater everglades slough. Periodic tidal inundation, rainfall and overland freshwater flow are the forcing functions on surface soil infiltration and drainage in the adjacent estuary mangrove forest peat. Empirical soil hydraulic conductivity (K) for the mangrove peat soil is needed for hydrologic modeling efforts such as "The Tides and Inflows in the Mangroves of the Everglades" (TIME). South Florida has a bi-seasonal weather pattern of a dry and mild winters and a wet tropical summers. During the drier winter months (November-May), the mangrove peat has a 30-60 cm, unsaturated vadose zone and in the wet summer months (June-October), the peat is totally saturated. This study's purpose is to determine reliable values of soil hydraulic conductivity for mangrove peat under both the unsaturated Kfs and saturated Ksat soil conditions. Rycroft (1975) reported that field measurements are the preferred method of testing hydraulic conductivity of peat. The principle field method used to determining soil hydraulic conductivity Kfs under unsaturated conditions utilized a cylindrical permeameter (Guelph Permeameter) and the auger-hole method was used to determine soil hydraulic conductivity Ksat under saturated soil conditions. The hydraulic conductivity K samples were taken along a 300-meter transect, perpendicular to the south Harney riverbank through a mixed mangrove riparian forest and ending in a freshwater sawgrass prairie. Initial measurements were recorded in May-June 2001. A second year measurement set will be collected in March-April 2002. Hydraulic conductivity K measurements were observed in shallow peat holes (15 cm) at five equally spaced sample sites (60 m) from the river edge. Soil cores were taken at each sampling site to determine soil profile and bulk density.

Anderson, G. H.; Smith, T. J.

2002-05-01

210

FOREST HEALTH MONITORING 1992 ACTIVITIES PLAN  

EPA Science Inventory

Forests, which cover approximately one-third of the United States, are an important part of the U.S. economy, culture, and ecology. n response to legislative mandate and for our environment, several government agencies have been working together to develop a program to monitor th...

211

Toward global baselines and monitoring of forest cover for REDD: the Global Forest Cover Change project  

Microsoft Academic Search

Monitoring, Reporting, and Verification (MRV) procedures in support of Reducing Emissions from Deforestation and forest Degradation (REDD) require the establishment of historical baselines of forest cover and changes, as well as consistent monitoring of subsequent forest gains and losses over time. Under the NASA MEaSUREs program, the Global Forest Cover Change project is using the USGS Global Land Survey (GLS)

J. O. Sexton; C. Huang; J. G. Masek; M. Feng; R. Narasimhan; E. F. Vermote; M. C. Hansen; R. E. Wolfe; S. Channan; J. R. Townshend

2010-01-01

212

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

NASA Astrophysics Data System (ADS)

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.

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

2010-06-01

213

Characteristics of Scylla spp. (Decapoda: Portunidae) and Their Mangrove Forest Habitat in Ngaremeduu Bay, Republic of Palau 1  

Microsoft Academic Search

Three species of mangrove crabs (Scylla spp.) were captured in live traps in Ngaremeduu Bay on the island of Babeldaob, Republic of Palau. Most were S. serrata, but one individual each of S. olivacea and S. paramamosain was also trapped, establishing existence of a biogeographic gradient in mangrove crab species diversity across the Micronesian archipelago. Species composition of mangrove trees

Katherine C. Ewel; Stacy Rowe; Blake McNaughton; Kimberly M. Bonine

2009-01-01

214

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

NASA Astrophysics Data System (ADS)

The diversity, abundance, biomass and community structure of crustacean and molluscan macrofauna were studied in the Ranong mangrove forest ecosystem on the Andaman Sea coast of southern Thailand. After a history of commercial exploitation the mangroves along the Klong Ngao tidal creek have been assigned conservation status within a new Ranong Biosphere Reserve established in 1997. Over the past 12 years, several areas of mangrove destroyed or degraded by wood harvesting, tin mining and aquaculture, have been rehabilitated on a pilot basis by planting monocultures of mangrove seedlings using four common local species ( Rhizophora apiculata, R. mucronata, Bruguiera cyclindrica and Ceriops tagal). These plantation forests with different past management histories were compared with a natural, mixed, mature mangrove forest which has been conserved for about 40 years. Macrofauna were sampled within a 100 m 2 vegetation quadrat in each study site. Crustaceans were sampled quantitatively by 3×15 min timed hand catches per site. Molluscs were sampled in 3× m 2 quadrats positioned around three randomly selected trees in each vegetation quadrat. The lowest crustacean and molluscan diversity was recorded from the former tin mining site. The highest diversity was recorded from a Rhizophora plantation in the natural mixed forest area for both crustaceans and molluscs. The vegetation community structure was not correlated with the environmental variables measured, or with macrofauna community structure. Of the environmental parameters chosen, the crustacean community structure was best expressed by shore level, while for molluscan diversity and abundance it was soil moisture content. The macrofauna community structure at the tin mining site was significantly different to the other sites, and was dominated by a single species of crab, Metaplax elegans. Grapsid crabs, especially sesarmid species, dominated over ocypodid crabs in the mature forest site, whereas Uca species and other 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.

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

2002-09-01

215

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

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.

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

2013-01-01

216

Activity patterns, feeding and burrowing behaviour of the crab Ucides cordatus (Ucididae) in a high intertidal mangrove forest in North Brazil  

Microsoft Academic Search

Activity patterns, feeding and burrowing behaviour of the economically important semi-terrestrial mangrove crab Ucides cordatus (Ucididae, L. 1763) was studied in a high intertidal Rhizophora mangle forest stand in Bragança, North Brazil. Video observations in the rainy and dry season were conducted over 24 h cycles at different lunar phases to investigate the behaviour of these litter-feeding crabs outside their burrows.

Inga Nordhaus; Karen Diele; Matthias Wolff

2009-01-01

217

Rapid sediment accumulation and microbial mineralization in forests of the mangrove Kandelia candel in the Jiulongjiang Estuary, China  

NASA Astrophysics Data System (ADS)

Rates of sediment accumulation and microbial mineralization were examined at three Kandelia candel forests spanning the intertidal zone along the south coastline of the heavily urbanized Jiulongljiang Estuary, Fujian Province, China. Mass sediment accumulation rates were rapid (range: 10-62 kg m -2?y -1) but decreased from the low- to the high-intertidal zone. High levels of radionuclides suggest that these sediments originate from erosion of agricultural soils within the catchment. Mineralization of sediment carbon and nitrogen was correspondingly rapid, with total rate of mineralization ranging from 135 to 191 mol C m -2?y -1 and 9 to 11 mol N m -2?y -1; rates were faster in summer than in autumn/winter. Rates of mineralization efficiency (70-93% for C; 69-92% for N) increased, as burial efficiency (7-30% for C; 8-31% for N) decreased, from the low-to the high-intertidal mangroves. Sulphate reduction was the dominant metabolic pathway to a depth of 1 m, with rates (19-281 mmol S m -2?d -1) exceeding those measured in other intertidal deposits. There is some evidence that Fe and Mn reduction-oxidation cycles are coupled to the activities of live roots within the 0-40 cm depth horizon. Oxic respiration accounted for 5-12% of total carbon mineralization. Methane flux was slow and highly variable when detectable (range: 5-66 ?mol CH 4 m -2?d -1). Nitrous oxide flux was also highly variable, but within the range (1.6-106.5 ?mol N 2O m -2?d -1) measured in other intertidal sediments. Rates of denitrification were rapid, ranging from 1106 to 3780 ?mol N 2 m -2?d -1, and equating to 11-20% of total sediment nitrogen inputs. Denitrification was supported by rapid NH 4 release within surface deposits (range: 3.6-6.1 mmol m -2?d -1). Our results support the notion that mangrove forests are net accumulation sites for sediment and associated elements within estuaries, especially Kandelia candel forests receiving significant inputs as a direct result of intense human activity along the south China coast.

Alongi, D. M.; Pfitzner, J.; Trott, L. A.; Tirendi, F.; Dixon, P.; Klumpp, D. W.

2005-06-01

218

Soil redox conditions and plant-soil relationships in a micronesian mangrove forest  

NASA Astrophysics Data System (ADS)

We examined characteristics of the soil environment related to redox in the rhizospheres of three mangrove species that commonly grow in similar hydrogeomorphic settings: Rhizophora apiculata BL, Bruguiera gymnorrhiza (L.) Lamk., and Sonneratia alba J. Redox potential (Eh) values and extractable P concentrations were significantly higher, whereas soluble reactive P (SRP) concentrations were significantly lower in Bruguiera plots than in either Rhizophora or Sonneratia plots. Correlations among Eh, SRP, pyrite and extractable P were significant only at plots with negative Eh values. Sonneratia and Bruguiera plots had significantly different soil redox conditions. Bruguiera plots were characterized by more oxidized soil conditions (ca. 80 mV), lower dissolved P concentrations in porewater (ca. 50%), and higher extractable P concentrations in soil (ca. 25%). Differences in Eh and P reflect real differences among species and appeared not to be associated with hydrology. Species-specific differences may be engendered by the trees themselves, or they may reflect microsite differences that have favored the germination, growth, and survival of particular mangrove species.

Gleason, S. M.; Ewel, K. C.; Hue, N.

2003-04-01

219

Hidden in the mangrove forest: the cryptic intertidal mite Carinozetes mangrovi sp. nov. (Acari, Oribatida, Selenoribatidae).  

PubMed

The small archipelago of Bermuda is a geologically young landmass in the Western Atlantic Ocean and recently turned out to be inhabited by a number of intertidal oribatid mites. One newly described species, Carinozetes bermudensis, showed an unusual vast range of habitats like sandy beaches, rocky substrate and mangroves. In the present study, 13 Bermudian populations of C. bermudensis were analysed to verify species integrity of specimens from different microhabitats. A morphometric analysis of 17 continuous variables as well as a molecular genetic investigation of the mitochondrial cytochrome oxidase subunit I revealed the existence of a new species Carinozetes mangrovi sp. nov., inhabiting exclusively intertidal algae growing on mangrove roots. Although both species are morphologically nearly identical, the configuration of the genus-specific ventral carinae represents a clear diagnostic character. The high genetic divergence of approximately 12 % of the cytochrome oxidase subunit I gene sequence between C. bermudensis and C. mangrovi sp. nov. suggests that these two species diverged before the emergence of the Bermuda islands. Accordingly, both of them are older than the geologically young archipelago of Bermuda. PMID:24687175

Pfingstl, Tobias; Lienhard, Andrea; Jagersbacher-Baumann, Julia

2014-08-01

220

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)

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 ocypodid crabs, feeding on detritus and microphytobenthos, correlated with sediment characteristics like median grain size and organic content. The crab community was strongly dominated by one species at six stations, however, this was not correlated to the degree of logging. Leaf-feeding crab and mangrove tree diversity was correlated at areas of one hectare (stations), but not at a lower spatial scale (areas of 100 m 2, "zone"). Species richness of leaf-feeding crabs was not linked to forest diversity. Hence a functional relation between leaf-feeding crab and tree species diversity could not be proven.

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

2012-01-01

221

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

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.

Ward, Greg A.; Smith, Thomas J., III

2007-01-01

222

Aerial monitoring and measurement of forest fires  

NASA Astrophysics Data System (ADS)

This paper presents a system for forest fire monitoring using aerial images. The system uses the images taken from a helicopter, the GPS position of the helicopter, and information from a Geographic Information System (GIS) to locate the fire and to estimate in real-time their properties. Currently, the images are taken by a non-stabilized camera. Then, image processing for image stabilization and movement estimation is applied to cancel the vibration and to estimate the change in the camera orientation. Another image processing stage is the computation of the fire front and flame height features in the images. This process is based on color processing and thresholding, followed by contour computation. Finally, the fire front is automatically geo-located by projecting the features over the terrain model obtained from the GIS. Furthermore, an estimation of the flame height is obtained. The aerial image processing, automatic georeferencing and measurement has been integrated in a forest fire fire monitoring system in which several moving or fixed visual and infrared cameras can be used. The system provides in real-time the evolution of the fire-front and the flame height, and obtains a 3D perception model of the fire. The paper shows some results obtained with the application with images taken in real forest-fire experiments, in the framework of the INFLAME project funded by the European Commission.

Merino, Luis; Gomez-Rodriguez, Francisco; Arrue, Begona C.; Ollero, Anibal

2002-07-01

223

Microbulbifer chitinilyticus sp. nov. and Microbulbifer okinawensis sp. nov., chitin-degrading bacteria isolated from mangrove forests.  

PubMed

Three chitin-degrading strains representing two novel species were isolated from mangrove forests in Okinawa, Japan. The isolates, ABABA23(T), ABABA211 and ABABA212(T), were Gram-negative, non-spore-forming, strictly aerobic chemo-organotrophs. The novel strains produced Q-8 as the major isoprenoid quinone component. The predominant fatty acids were iso-C??:? and C??:?. On the basis of 16S rRNA gene sequence analysis, the isolates were closely affiliated with members of the genus Microbulbifer. The DNA G+C contents of strains ABABA23(T) and ABABA212(T) were 57.8 and 60.2 mol%, respectively. DNA-DNA relatedness values between these two strains and Microbulbifer reference strains were significantly lower than 70?%, the generally accepted threshold level below which strains are considered to belong to separate species. Based on differences in taxonomic characteristics, the three isolates represent two novel species of the genus Microbulbifer, for which the names Microbulbifer chitinilyticus sp. nov. (type strain, ABABA212(T)?=?JCM 16148(T)?=?NCIMB 14577(T)) and Microbulbifer okinawensis sp. nov. (type strain, ABABA23(T)?=?JCM 16147(T)?=?NCIMB 14576(T); reference strain, ABABA211) are proposed. PMID:20935083

Baba, Atsushi; Miyazaki, Masayuki; Nagahama, Takahiko; Nogi, Yuichi

2011-09-01

224

Linking Forest Carbon Monitoring with Management Decisions  

NASA Astrophysics Data System (ADS)

Managing forests to increase carbon stocks or reduce emissions requires knowledge of how management practices effect carbon pools over time, and inexpensive techniques to monitor activities. Here we discuss our approach to integrate the multi-tier monitoring data from the North American Carbon Program (NACP) with management decisions by linking bottom-up and top-down ecosystem models with decision-support tools. Monitoring carbon stocks and fluxes in the NACP involves a multi-tier hierarchy of observation methods: remote sensing, inventories, landscape biometrics, and flux towers. We use the GIS version of PnET-CN to scale up and map observations from flux towers, landscape biometrics, and inventories to areas of approximately 50 km2 around flux tower sites. The NASA-CASA model is used to scale down remote sensing observations from the MODIS sensor and biophysical maps to the same areas. Mapped estimates of productivity and biomass that embed consequences of land disturbances and forest age structure are used to compare and reconcile the top-down and bottom-up approaches, and to provide input to decision-support tools. Key information for the decision-support tools includes (1) estimates of carbon stocks and quantified impacts of management activity; (2) estimates of net ecosystem production (NEP) and changes in carbon pools; and (3) estimates of forest/atmosphere carbon fluxes and relevant effects from various environmental controls. To demonstrate the relevance of this work to land managers, we illustrate how this information can be used for estimating and reporting carbon stocks and changes in carbon stocks to the national greenhouse gas registry.

Birdsey, R.; Pan, Y.; Potter, C.; Hom, J.; Clark, K.; van Tuyl, S.

2006-12-01

225

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

PubMed

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

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

2007-11-01

226

Impacts of shrimp farm effluent on water quality, benthic metabolism and N-dynamics in a mangrove forest (New Caledonia)  

NASA Astrophysics Data System (ADS)

Water quality parameters, sediment oxygen demand (SOD), dissolved organic and inorganic nutrient fluxes, and N-cycle processes (nitrification; denitrification; dissimilatory nitrate reduction to ammonium (DNRA)) were determined in a New Caledonian mangrove receiving shrimp farm effluent and a natural mangrove. Effluent was enriched in nutrients and organic matter, and significantly stimulated SOD and nutrient regeneration rates in the receiving sediments. All N-cycling processes were stimulated between ˜2 and 12-fold in the sediments receiving effluents compared to the natural mangrove. However, due to the preferential enhancement of DNRA compared to denitrification, there was no significant increase in net nitrogen elimination compared to the significant increase in sediment nutrient regeneration rates. These results indicate that the mangroves are only a partial filter for the shrimp farm effluent, as confirmed by the elevated nutrient concentrations measured in an external, marine creek of the effluent receiving mangrove.

Molnar, Nathalie; Welsh, David T.; Marchand, Cyril; Deborde, Jonathan; Meziane, Tarik

2013-01-01

227

Monitoring of Pine Forests in the Komi Republic  

Microsoft Academic Search

Because of increasing atmospheric pollution by industrial emissions, forest biogeocenoses growing in large industrial regions fail to neutralize various toxic substances and gradually decline (Kondratyuk et al. , 1980; Getko, 1989). In 1985, the UN Economic Commission for Europe developed the Program of Forest Monitoring based on the examination of forests by bioindication criteria and the chemical testing of foliage,

N. V. Torlopova; S. V. Il'chukov

2004-01-01

228

Mangrove Resources  

NSDL National Science Digital Library

Florida Plants Online provides this resource on mangroves, featuring brief annotations and links to dozens of mangrove-related pages. Although the pages described at Florida Plants Online vary in depth and quality, many are worthwhile.

2000-01-01

229

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)

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 ecosystem engineering activities are still performed. However, bioturbation may be reduced as crab biomass and body size were smaller in the gaps. Follow-up assessments and field experiments are needed to understand the crabs' role in processing the woody debris, their long-term community dynamics and possible feed-backs between species shifts and gap regeneration.

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

230

Burrow morphology of Uca uruguayensis and Uca leptodactylus (Decapoda: Ocypodidae) from a subtropical mangrove forest in the western Atlantic.  

PubMed

The continuous excavation of burrows by fiddler crabs generates bioturbation in the sediment, which can be estimated from burrow morphology. The aim of the present study was to describe the burrow morphology of Uca uruguayensis and U. leptodactylus and its relationship with demography of resident individuals and to estimate the level of bioturbation in the sediment generated by each species. For all individuals from each of the 2 species, sex was determined and the carapace width (CW; mm) measured. Burrows were characterized according to burrow diameter (BD; mm), maximum burrow depth (MBD; mm) and burrow volume (BV; cm(3) ). The density of each species in the study area was also evaluated. In both species, the males were larger and occupied burrows with higher BV compared to females. Differences between sexes in relation to the burrow characteristics might reflect sexual dimorphism within the group and are probably related to the fact that males use the burrows for mating. BD and BV showed significant positive relationships with the size of resident crabs. The amount of sediment removed per burrow was estimated from mean BV: 10.78 cm(3) of sediment/burrow for U. uruguayensis and 12.38 cm(3) of sediment/burrow for U. leptodactylus. Despite the density and depth differences between the 2 species, the similarity in burrow volume suggests that U. uruguayensis and U. leptodactylus present the same importance in terms of the bioturbation process. Burrow morphology is highly associated with characteristics of the occupant, although extrinsic factors should also be considered, and its description can provide estimates on the bioturbation generated by Uca species in mangrove forests. PMID:24020469

Machado, Glauco B O; Gusmão-Junior, João B L; Costa, Tânia M

2013-09-01

231

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

USGS Publications Warehouse

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.

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

2009-01-01

232

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

PubMed

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

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

2013-04-01

233

Redox conditions and heavy metals distribution in mangrove forests receiving effluents from shrimp farms (Teremba Bay, New Caledonia)  

Microsoft Academic Search

Purpose  The mangroves of New Caledonia, in the south Pacific, act as a buffer between a lagoon of more than 20,000 km2 and the island, which is characterized by ultramafic rocks and lateritic soils that are exploited for their richness in heavy\\u000a metals. We will provide a better understanding of the redox conditions, and of heavy metal distributions in mangroves receiving\\u000a shrimp

Cyril Marchand; Elisabeth Lallier-Vergès; Michel Allenbach

2011-01-01

234

A review on the present status and management of mangrove wetland habitat resources in Bangladesh with emphasis on mangrove fisheries and aquaculture  

Microsoft Academic Search

The mangrove forest of Bangladesh, the largest continuous mangrove bulk, is one of the most important features of the coastal area of the country. The existence of the mangrove has increased the values of other coastal and marine resources such as the coastal and marine fisheries by increasing productivity and supporting a wide biological diversity. The deltaic mangrove of Bangladesh

235

Mangroves as filters of shrimp pond effluent: predictions and biogeochemical research needs  

Microsoft Academic Search

Preliminary estimates of the ratio of mangrove forest: shrimp pond area necessary to remove nutrients from shrimp pond effluent are made using budgets of nitrogen and phosphorus output for semi-intensive and intensive shrimp ponds combined with estimates of total net primary production in Rhizophora-dominated mangrove forests in tropical coastal areas. If effluent is delivered directly to mangrove forest plots, it

A. I. Robertson; M. J. Phillips

1995-01-01

236

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

NASA Astrophysics Data System (ADS)

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=d?544/d?1736, for N estimation PVI = ?514 - 0.9*?676 - 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.

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

2011-12-01

237

Energy dynamics and its implication to biosphere-atmosphere exchange of CO 2, H 2O and CH 4 in a tropical mangrove forest canopy  

NASA Astrophysics Data System (ADS)

Amount of radiant energy (short wave) available to drive biosphere-atmosphere exchange of CO 2, H 2O, CH 4 and for transfer into other energy forms were determined for a tropical mangrove forest at the land ocean boundary of north-east (NE) coast of Bay of Bengal from January to December 2006. The mean annual incoming short wave radiation (435±32.8 W m -2) was partitioned into 29% sensible heat, 35% latent heat, 4% ground heat, 7% physical storage energy and 10% photosynthetic storage energy. The mean budget closing energy flux (68.96±24.6 W m -2) or, budget error was 15.8% of incoming short wave radiation. In Varimax factor analysis, budget closing energy flux showed high loading in association with leaf chlorophyll of different mangrove species, indicating its major role for reflectivity of the surface for short wave. There was significant seasonality in CO 2 exchange with net primary productivity of 14.1 ?mol m -2 s -1. The mean methane emission was found higher (7.29 ?g m -2 s -1) during the daytime than that of night time (1.37 ?g m -2 s -1) with maximum methane emission rates of 36.1 and 21.1 ?g m -2 s -1 in December and January, respectively. Stepwise multiple regression analysis between storage energy [? Hs( P)] and fluxes of CO 2, CH 4, H (sensible heat), HL (latent heat of evaporation), ? R (budget closer energy) showed that the combined explained variability for CO 2 flux, evapotranspiration and budget closer energy (39%) was less than that of CH 4 and sensible heat flux (46%). The extent of warming effect by CH 4 and sensible heat flux was predominant over the resultant cooling effect due to the processes such as photosynthesis, evapotranspiration and albedo. The mangrove forest with two trademarks of low albedo and high surface roughness was poorly coupled to the environment.

Ganguly, D.; Dey, M.; Mandal, S. K.; De, T. K.; Jana, T. K.

238

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

USGS Publications Warehouse

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.

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

2011-01-01

239

Satellite Data Aid Monitoring of Nation's Forests  

NASA Technical Reports Server (NTRS)

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.

2014-01-01

240

The role of mangroves in attenuating storm surges  

USGS Publications Warehouse

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.

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

2012-01-01

241

ANNUAL REPORT: FOREST HEALTH MONITORING, NEW ENGLAND 1990  

EPA Science Inventory

This publication reports the findings of the 1990 (first) Northeastern Forest Health Monitoring field season. he objectives were to establish baseline conditions for assessing attributes of forest health. ield visits were made to 263 sample plots across the 6 New England states, ...

242

Frugivory by insects on mangrove propagules: effects on the early life history of Avicennia marina  

Microsoft Academic Search

This study investigates how herbivory by larval insects on fruit of the mangrove Avicennia marina affects the subsequent establishment, growth, and survivorship of its seedlings. Research was done in a temperate mangrove forest in Australia where the larvae of two species of insects were the dominant frugivores: the mangrove fruit fly Euphranta marina and the mangrove plume moth Cenoloba obliteralis.

Todd E. Minchinton; Mia Dalby-Ball

2001-01-01

243

Sap flow characteristics of neotropical mangroves in flooded and drained soils  

USGS Publications Warehouse

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. racemosa having the greatest midday Js of about 26 g H2O m-2 s-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. ?? 2007 Heron Publishing.

Krauss, K. W.; Young, P. J.; Chambers, J. L.; Doyle, T. W.; Twilley, R. R.

2007-01-01

244

Below-ground root yield and distribution in natural and replanted mangrove forests at Gazi bay, Kenya  

Microsoft Academic Search

Estimation of total biomass in woody ecosystems is important because of its relevance to nutrient turnover and the potential to store carbon. Most work on mangrove biomass, particularly in the Western Indian Ocean Region, has concentrated on the above-ground component; comparatively little is known on below-ground biomass. The current study was conducted at Gazi bay on the southern coast of

F. Tamooh; M. Huxham; M. Karachi; M. Mencuccini; J. G. Kairo; B. Kirui

2008-01-01

245

An ordination study to view vegetation structure dynamics in disturbed and undisturbed mangrove forests in Kenya and Sri Lanka  

Microsoft Academic Search

The mangrove vegetation of a disturbed and undisturbed site in both Kenya and Sri Lanka was investigated in the field for three vegetation layers: adult trees, young trees, and juvenile trees. A minimum of 25 sample points, in which the vegetation was described and environmental factors (salinity, light intensity, land\\/water ratio, abun- dance of herbivorous crabs and snail abundance) were

F. Dahdouh-Guebas; J. G. Kairo; L. P. Jayatissa; S. Cannicci; N. Koedam

2002-01-01

246

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

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

247

Forest structure and species distribution along soil salinity and pH gradient in mangrove swamps of the Sundarbans  

Microsoft Academic Search

An analysis has been made in the Sundarbans mangroves to relate the community structure and distribution of species with soil salinity and pH gradients. Soil salinity (13.0 to 31.2 ppt) decreased with increasing distance from the tidal coast but no such trend was noticed in soil pH (7.0 to 7.9). Freque ncy of tidal inundation seemed to affect soil salinity.

HEMA JOSHI; M. GHOSE

248

An ordination study to view vegetation structure dynamics in disturbed and undisturbed mangrove forests in Kenya and Sri Lanka  

Microsoft Academic Search

The mangrove vegetation of a disturbed and undisturbed site in bothKenya and Sri Lanka was investigated in the field for three vegetation layers:adult trees, young trees, and juvenile trees. A minimum of 25 sample points, inwhich the vegetation was described and environmental factors (salinity, lightintensity, land\\/water ratio, abundance of herbivorous crabs and snailabundance)were measured or estimated, were taken on each

F. Dahdouh-Guebas; J. G. Kairo; L. P. Jayatissa; S. Cannicci; N. Koedam

2002-01-01

249

Taiga forest stands and SAR: Monitoring for subarctic global change  

SciTech Connect

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.

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

1992-03-01

250

Monitoring Strategies for REDD+: Integrating Field, Airborne, and Satellite Observations of Amazon Forests.  

National Technical Information Service (NTIS)

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 scal...

C. Souza C. Souza D. Morton M. Keller

2012-01-01

251

Gap creation and regenerative processes driving diversity and structure of mangrove ecosystems  

Microsoft Academic Search

Turnover within both mangrove and terrestrial forests is driven by stand development in conjunction with factors influencing tree death and replacement at various temporal and spatial scales. Development in terrestrial forests appears comparable with that in mangroves but turnover seems to differ considerably between these broad forest types. The most important difference is in the character of small forest gaps.

Norman C. Duke

2001-01-01

252

Monitoring Forest Succession Using Multitemporal Landsat Images: Factors of Uncertainties  

NASA Astrophysics Data System (ADS)

This study evaluates uncertainty factors in using multitemporal Landsat images for subtle change detection, including atmosphere, topography, phenology, sun and view angles. The study is based on monitoring forest succession with a set of multiple Landsat TM/ETM+ images spanning 15 years over the H. J. Andrews Experimental Forest in the Western Cascades of Oregon. The algorithms for removing atmospheric effects from remotely sensed images evaluated include a new version of dark object subtraction (DOS3) method, the dense dark vegetation (DDV) method, the path radiance (PARA) approach, and the 6S radiative transfer codes. We found that the DOS3 approach under-corrects the image, and the recently developed DDV and PARA approaches can produce surface reflectance values closely matching those produced by 6S using in situ measurements of atmospheric aerosol optical depth. Atmospheric effects reduce NDVI and Greenness, and increase Brightness and Wetness. Topography modifies Brightness and Greenness, but has minimal effects on NDVI and Wetness, and it interacts with sun angle. Forest stands at late successional stages are more sensitive to topography than younger stands. Though the study areas are covered predominantly by evergreen needle leaf forests, phenological effect is significant. Sun angle effects are confounded with phenology, and reflectance values for stands at different successional stages are related to sun angles nonlinearly. Though Landsat has a small field of view angle, the view angle effects from overlapping Landsat scenes for a mountainous forested landscape may not be ignored when monitoring forest succession with multitemporal images.

Song, C.

2004-05-01

253

The North American Carbon Program: Forest Monitoring and Modeling  

NASA Astrophysics Data System (ADS)

The North American Carbon Program (NACP) addresses fundamental questions about the buildup of greenhouse gases in the atmosphere. What is the role of land use and management? How much of fossil fuel emissions is taken up by ecosystems? How can we enhance carbon sinks? These questions were identified by the National Academy of Sciences as critical uncertainties in understanding the global carbon budget and in particular the role of North American lands. U.S. Agencies are coordinating an effort to develop and implement a carbon monitoring system, building on existing monitoring efforts. The NACP includes enhanced remote sensing of biomass, new sampling schemes for atmospheric and ocean CO2 concentrations, enhancements to land inventories, and expansion of intensive monitoring sites. Increased efforts will be made to integrate these various monitoring programs through modeling and analysis, and to develop comprehensive reports and databases. The forest land component involves development of a hierarchical, 4-tier monitoring approach that integrates the ongoing Forest Inventory and Analysis (FIA) Program of the USDA Forest Service with intensive-site monitoring. The growing array of AmeriFlux sites, where net ecosystem-atmosphere CO2 and energy exchange is measured, is a key element of the monitoring approach. A new monitoring tier (tier 3) is proposed that will link extensive FIA monitoring with the intensive flux sites. Tier 3 will include clusters of monitoring sites that represent conditions over large landscapes surrounding a flux site. For example, tier 3 sites may be selected to represent a chronosequence of forest land affected by management or natural disturbance. Measurements at tier 3 sites will include key components of the carbon balance that will allow statistically representative scaling of the intensive flux measurements to the larger landscape through linkage with extensive FIA sample plots. In addition to forest monitoring, forest land data bases and modeling are key activites of the NACP. Current and historical data, with explicit geographical representation of trends in management and disturbance, are required to attribute causes to observed changes in CO2 flux. Spatial and temporal representation of currently available data will need enhancement to produce consistent and comprehensive coverage. Data content will need enhancement for some regions that have not historically been sampled in timber-oriented inventoried. Use of remote sensing, statistical imputation, and ecosystem modeling will be required to enhance data sets. Ecosystem models also have a significant role in integrating observations from the various land and atmospheric sensors, and compiling estimates for a comprehensive report on the status of the North American carbon budget.

Birdsey, R.; Hollinger, D.; Sundquist, E.

2002-12-01

254

Toward global baselines and monitoring of forest cover for REDD: the Global Forest Cover Change project  

NASA Astrophysics Data System (ADS)

Monitoring, Reporting, and Verification (MRV) procedures in support of Reducing Emissions from Deforestation and forest Degradation (REDD) require the establishment of historical baselines of forest cover and changes, as well as consistent monitoring of subsequent forest gains and losses over time. Under the NASA MEaSUREs program, the Global Forest Cover Change project is using the USGS Global Land Survey (GLS) dataset of Landsat images to generate Earth Science Data Records (ESDRs) for monitoring forest cover over multiple decades at sub-hectare spatial resolution. These data products include layers representing forest cover, change, and fragmentation in 1975, 1990, 2000, and 2005, as well as atmospherically corrected surface reflectance images for these same GLS “epochs”. Monitoring at this scale requires high levels of automation and radiometric precision. Atmospheric correction is accomplished with the 6S radiative transfer code, and classification is performed with Support Vector Machines fit with training data gathered by automated procedures. Surface reflectance images for the 2000 and 2005 epochs were recently released for public use. For the 2000 epoch, 94% of images had Root-Mean Squared Difference (RMSD) less than 5% reflectance compared to coincident MODIS daily surface reflectance (MOD09) across all bands. For 2005, 92% of images based on Landsat-7 and Landsat-5 met this specification relative to MODIS daily surface reflectance and 16-day NBAR composites (MCD43A4), respectively. Forest cover and change maps are being validated against visually interpreted reference data; pilot studies conducted in several countries showed accuracies above 90%. Classification errors are predominantly due to poor discrimination of deciduous forests from crops and other herbaceous cover types, and so procedures have been devised for flagging and/or replacement of phenologically unsuitable GLS images. Web-based tools have been developed for rapid collection of multi-temporal reference data, and we are exploring ways to incorporate community efforts for validation through this interface. Accuracy assessments will be updated as algorithms are refined. This talk will describe project goals, algorithms, and product status, with additional emphasis on accuracy assessment of surface reflectance and forest cover products. These and forthcoming data records will provide crucial information to resource managers and scientists monitoring changes in forest cover over recent decades.

Sexton, J. O.; Huang, C.; Masek, J. G.; Feng, M.; Narasimhan, R.; Vermote, E. F.; Hansen, M. C.; Wolfe, R. E.; Channan, S.; Townshend, J. R.

2010-12-01

255

Methyl halide emissions from greenhouse-grown mangroves  

NASA Astrophysics Data System (ADS)

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.

Manley, Steven L.; Wang, Nun-Yii; Walser, Maggie L.; Cicerone, Ralph J.

2007-01-01

256

Kelp Forest Monitoring 1994 Annual Report. Channel Islands National Park.  

National Technical Information Service (NTIS)

The 1994 results of the Channel Islands Natonal Park Kelp Forest Monitoring Project are described in this report. Population dynamics of 68 taxa or categories of algae, fish, and invertebrates were measured at 16 permanent sites around the five islands wi...

D. Kushner D. Lerma D. Richards

1994-01-01

257

Kelp Forest Monitoring 1992 Annual Report. Channel Islands National Park.  

National Technical Information Service (NTIS)

The 1992 results of the Channel Islands Natioanl Park Kelp Forest Monitoring Project are described in this report. Population dynamics of 68 taxa or categories of algae, fish, and invertebrates were measured at 16 permanent sites around the five islands w...

D. Kushner D. Richards

1992-01-01

258

Community forest monitoring in REDD+: the ‘M’ in MRV?  

Microsoft Academic Search

Transparent, accountable, and sustainable monitoring, reporting and verification (MRV) systems are essential for any REDD+ framework. With the prospect of a global agreement on forest preservation on the horizon, establishing functional MRV systems is one of the major goals of so called ‘REDD Readiness’. However, due to the ambitious, worldwide scale of the prospective REDD+ framework, financial sustainability is a

Ben Palmer Fry

2011-01-01

259

Application of Remote Sensing Technologies for Forest Cover Monitoring  

NASA Astrophysics Data System (ADS)

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.

Agoltsov, Alexander; Sizov, Oleg; Rubtsova, Natalia

2014-05-01

260

Forest biomass monitoring with GNSS-R: Theoretical simulations  

NASA Astrophysics Data System (ADS)

GNSS-Reflectometry (GNSS-R) is a remote sensing technique which performs bistatic measurements of the earth surface scattering. This paper presents some theoretical simulations of the specular scattering coefficient of a forested area, with the aim of demonstrating the potentiality of GNSS-R in monitoring forest biomass. The study is performed by means of an electromagnetic model developed in the past years and tested over several vegetation covered sites in its active and passive version. Here, after showing a comparison between model results and measurements over a forest site in the monostatic configuration, and after summarizing other previous validations, the extension to the specular configuration, typical of GNSS-R systems, will be presented. Namely, simulations are carried out at circular polarization and a sensitivity analysis of the received power in the specular configuration to some soil and forest parameters is shown.In the GNSS-R configuration, the theoretical response of vegetation shows a decreasing trend with increasing biomass, due to the increasing attenuation by the plant canopy which reduces the coherent scattering from the soil. The latter, however, remains higher than incoherent scattering even when forest biomass is large, especially at RL polarization and low incidence angle. Consequently the magnitude of the received power is sensitive to the forest biomass without exhibiting the typical saturation of radar backscattering measurements, and it may thus allow biomass retrieval.

Ferrazzoli, P.; Guerriero, L.; Pierdicca, N.; Rahmoune, R.

2011-05-01

261

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

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

262

A review on the present status and management of mangrove wetland habitat resources in Bangladesh with emphasis on mangrove fisheries and aquaculture  

Microsoft Academic Search

The mangrove forest of Bangladesh, the largest continuous mangrove bulk, is one of the most important features of the coastal\\u000a area of the country. The existence of the mangrove has increased the values of other coastal and marine resources such as\\u000a the coastal and marine fisheries by increasing productivity and supporting a wide biological diversity. The deltaic mangrove\\u000a of Bangladesh

2005-01-01

263

Molecular cloning of functional genes for high growth-temperature and salt tolerance of the basidiomycete Fomitopsis pinicola isolated in a mangrove forest in Micronesia.  

PubMed

Several functional genes encoding putative proteins, heat shock protein 70, sphingosine phosphate lyase, and Na+/H+ antiporter, were cloned from the basidiomycete Fomitopsis pinicola, a wood-rotting fungus isolated in the tropical mangrove forest of Pohnpei Island of the Federated States of Micronesia. The deduced amino acid sequences of the obtained genes involved in heat shock resistance, lipid synthesis, and salt tolerance showed diverse similarities to other homologous proteins. Molecular phylogenetic trees of these proteins suggested that encoded proteins of the cloned genes of F. pinicola differed remarkably from other homologs in various organisms, even fungal proteins. Putative candidates for other genes related to several cellular metabolisms were also amplified, implying the possible existence of those genes in F. pinicola. This is the first report of possibly functional genes derived from a basidiomycetous mushroom growing in tropical islands such as Micronesia. The genes found in this study might play important roles in the cellular survival of the basidiomycete F. pinicola under severe environmental conditions. PMID:17213639

Miyazaki, Yasumasa; Hiraide, Masakazu; Shibuya, Hajime

2007-01-01

264

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)

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 probably diversifying at mid latitudes. Later on, they slowly became restricted to lower latitudes as seen today. This fluctuation appears to be linked to climate change and are still reflected by the regional diversity of these groups, which reflect rather well rain forest evolution. When tracing the fossil record of rain forest plants we clearly see a pattern that suggests the onset of this type of environment during the late Late Cretaceous and spread during the early Tertiary with phases of retreat during the Oligocene and from the mid-Miocene onwards.

Mohr, Barbara; Coiffard, Clément

2014-05-01

265

Siberian taiga forest regeneration monitoring with winter LANDSAT ETM+ images  

NASA Astrophysics Data System (ADS)

Monitoring the post-fire regeneration is important for Siberian taiga forest where fires occur frequently. Satellite images taken in summer have been often used in analyses of vegetation. However, in the sparse stands of Siberian taiga forest with varied types of forest floors, it is difficult to extract high trees' conditions and distributions from those images. Instead, we used for the analysis the LANDSAT ETM+ images taken in winter, when almost all high tree species there had fallen their leaves down and the forest floor was covered homogeneously by snow, which had very high reflectance in visible and low reflectance in longer wavelength. Bands 2 (visible), 4 (near-infrared), and 5 (mid-infrared) of the winter ETM+ images are compared with stands' basal area (BA) and height density (HD) that represents a relative congestion of the forest crown above observed from the floor. The results show that the total BA has a correlation with the visible band where the contrast of reflectance between trees and snow is maximum, while total HD has a relationship with the middle infrared band where the contrast is minimum. In addition, the near infrared has a relation ship with the BA of pines that are the only evergreen species of the region. Since HD has a positive correlation with the stand density, HD can be then interpreted to stand density and DBH.

Takao, G.; Kushida, K.; Maximov, T. C.; Kononov, A. V.; Desyatkin, R. M.; Fedorov, A. N.; Torgovkin, Y. Y.

2001-12-01

266

An ecological analysis of soil sarcodina at Dongzhaigang mangrove in Hainan Island, China  

Microsoft Academic Search

The community structure of soil sarcodina in three different habitats within a typical mangrove forest in Dongzhaigang, Hainan, China was investigated with qualitative and quantitative analyses. The three habitats were Site A (bare land without vegetation), Site B (artificially planted mangroves) and Site C (natural mangroves). The abundance, species diversity, dominance and community similarity index of soil sarcodina in fresh

Q. Y. Liao; J. Li; J. H. Zhang; M. Li; Yan Lu; R. L. Xu

2009-01-01

267

Mangroves enhance the biomass of coral reef fish communities in the Caribbean  

Microsoft Academic Search

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

Peter J. Mumby; Alasdair J. Edwards; J. Ernesto Arias-González; Kenyon C. Lindeman; Paul G. Blackwell; Angela Gall; Malgosia I. Gorczynska; Alastair R. Harborne; Claire L. Pescod; Henk Renken; Colette C. C. Wabnitz; Ghislane Llewellyn

2004-01-01

268

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

Microsoft Academic Search

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

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

2011-01-01

269

Applications of Turbidity Monitoring to Forest Management in California  

Microsoft Academic Search

Many California streams have been adversely affected by sedimentation caused by historic and current land uses, including\\u000a timber harvesting. The impacts of timber harvesting and logging transportation systems on erosion and sediment delivery can\\u000a be directly measured, modeled, or inferred from water quality measurements. California regulatory agencies, researchers, and\\u000a land owners have adopted turbidity monitoring to determine effects of forest

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

2007-01-01

270

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

USGS Publications Warehouse

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 was relatively more affected by the disturbance than wet season values. Complex leaf regeneration dynamics on damaged trees during ecosystem recovery are hypothesized to lead to the variable dry versus wet season impacts on daytime NEE. In contrast, nighttime CO 2 release (i.e., nighttime respiration) was consistently and significantly greater, possibly as a result of the enhanced decomposition of litter and coarse woody debris generated by the storm, and this effect was most apparent in the wet seasons compared to the dry seasons. The largest pre- and post-storm differences in NEE coincided roughly with the delayed peak in cumulative mortality of stems in 2007-2008. Across the hurricane-impacted region, cumulative tree mortality rates were also closely correlated with declines in peat surface elevation. Mangrove forest-atmosphere interactions are interpreted with respect to the damage and recovery of stand dynamics and soil accretion processes following the hurricane. ?? 2011.

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

2012-01-01

271

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)

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.

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

2013-01-01

272

Mangroves and Crabs as Ecosystem Engineers in Zanzibar  

Microsoft Academic Search

Primary productivity within mangroves results from detrital and coprophagous interactions on the forest floor. The feeding behaviors of Sesarmid crabs (Decapoda:Brachyura) alter the structural and chemical composition of benthic sediment through the consumption and incorporation of mangrove leaf-litter. In doing so they create habitats for organisms that in turn provide an additional food source for herbivorous crabs. Species specific herbivory

Charlie Nicholson

2009-01-01

273

Mangroves and sediment dynamics along the coasts of southern Thailand  

Microsoft Academic Search

Mangroves are a specific type of evergreen forest that is found along the coastlines of tropical and subtropical regions, particularly along deltas and bays where rivers discharge freshwater and sediment to the sea. These mangroves provide important ecological and socio-economic functions to coastal dwellers and societies. For example, they are natural spawning and living ground for many species of fish

U. Thampanya

2006-01-01

274

Severe hail damage to mangroves at Port Curtis, Australia  

Microsoft Academic Search

A hailstorm in October 1994 was found to have moderately or severely impacted on 5.3% of the mangrove forests in Port Curtis. All mangrove species showed evidence of hail damage, including the three most common species (Rhizophora stylosa, Ceriops tagal and Avicennia marina). Physical effects of hail damage included stripping of leaves from plants, holes punched through leaves, bruising to

W. A. Houston

1999-01-01

275

Monitoring Forest Regrowth Using a Multi-Platform Time Series  

NASA Technical Reports Server (NTRS)

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 techniques typically are not consistent for the same scene imaged under different illumination conditions, especially in the mountainous regions. In addition, it is difficult to correct for atmospheric and instrumental differences between multiple scenes in a time series. In this paper, we present an approach for monitoring forest cutting/regrowth in a semi-mountainous portion of the southern Gifford Pinchot National Forest using a multisensor-time series composed of MSS, TM, and AVIRIS images.

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

1996-01-01

276

Importance of estuarine mangroves to juvenile banana prawns  

NASA Astrophysics Data System (ADS)

Offshore catches of banana prawns, Penaeus merguiensis, are correlated with the extent of mangrove forests. However, recent evaluation has questioned whether the apparent relationship between juvenile penaeids and mangroves reflects specific utilisation of mangroves or just the use of shallow, organically rich, muddy habitats. We investigated this by focussing on juvenile P. merguiensis within 30 mangrove estuaries spanning 650 km of the coast of north-eastern Australia. We investigated a range of hierarchically clustered spatial scales and within-estuary spatial resolutions, as well as variables representing a variety of estuary structural factors, anthropogenic impacts, and particular hypotheses about the ways in which mangroves could influence P. merguiensis catch per unit effort (CPUE). Estuary to estuary differences, rather than climatic zone or the proximity of other estuaries, was the major large scale spatial influence on CPUE. At the among-estuaries scale mangrove extent appeared to influence CPUE but was extensively confounded with the effects of two non-mangrove variables; intertidal extent and substrate type. The fact that 3 alternative measures of connectivity with mangrove forests were not influential, points to the importance of the non-mangrove variables rather than mangrove extent. At the within-estuary scale, P. merguiensis CPUE was correlated with the extent of shallow water but not with mangrove variables. The spatial and temporal extent of sampling support a strong conclusion that factors associated with mangroves alone do not drive abundances of juvenile prawns. Nevertheless, despite being the dominant habitat, mangroves are only one of a mosaic of interacting habitats occurring in the tropical estuaries inhabited by juvenile penaeids (Sheaves, 2009), so causal relationships are complex and difficult to define unambiguously.

Sheaves, Marcus; Johnston, Ross; Connolly, Rod M.; Baker, Ronald

2012-12-01

277

Nutrient Controls on Biocomplexity of Mangrove Ecosystems  

USGS Publications Warehouse

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.

McKee, Karen L.

2004-01-01

278

Mangrove Colonization: Mangrove Progression Over the Growing Pak Phanang (SE Thailand) Mud Flat  

Microsoft Academic Search

A combination of remote sensing techniques andin 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

N. Panapitukkul; C. M. Duarte; U. Thampanya; P. Kheowvongsri; N. Srichai; O. Geertz-Hansen; J. Terrados; S. Boromthanarath

1998-01-01

279

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

PubMed

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 studies of this population. PMID:24386460

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

2013-01-01

280

Mangrove macrobenthos: Assemblages, services, and linkages  

NASA Astrophysics Data System (ADS)

Macrobenthic assemblages are relatively poorly known compared to other components of the mangrove ecosystem. Tropical mangroves support macrobenthic biodiversity resources yet to be properly documented and interpreted. Some methodological challenges, such as the generally high spatial heterogeneity and complexity of the habitat, evidently reduce sampling efficiency and accuracy, while also leaving some microhabitats under-sampled. Macrobenthic assemblage structure seems to be influenced by local environmental conditions, such as hydroperiod, organic matter availability and sediment characteristics. Brachyurans, gastropods and oligochaetes dominate in the sediment, with the former two groups also common on hard surfaces provided by tree trunks, while insects and arachnids inhabit the canopy. Traditionally, studies of mangrove macrobenthos have focused on assemblage structure or the biology of individual species, but more complex inter-specific interactions and the inter-relationship between habitat and the biota are recently being addressed. Brachyuran crabs are the best-studied macrobenthos group, but many issues about their role in mangrove ecosystem dynamics are still controversial. Despite many species of mangrove macrobenthos being referred to as 'trophic dead ends', most serve as important links between recalcitrant mangrove organic matter and estuarine secondary production, through feeding excursion by mobile nekton during the high tide, and macrobenthos-mediated processing and exportation of organic matter. A significant difference in the standing crop biomass of forests between the Indo-west-Pacific (IWP)' and Atlantic-east-Pacific (AEP) mangroves may be related to the difference in species richness of mangrove as well as macrobenthos diversity in the two bioregions. Such differences in assemblage structure may also result in different ecosystem functioning, but the nature of the links is, however, yet to be explored. There is also a strong need for evaluating mangrove macrobenthos assemblages as a component of the connected biotic resources in the land-sea continuum, rather than as an isolated faunal group.

Lee, S. Y.

2008-02-01

281

Improving monitoring of tropical forests using year 2009 SEVIRI data  

NASA Astrophysics Data System (ADS)

Mapping and monitoring tropical evergreen forests is a challenging task. Unlike the maximum once per day acquisition of a polar-orbiting satellite, the Geostationary Operational Environmental Satellite Series (GOES) will provide multiple daily views and thus significantly increase the chance to produce a high quality and high frequency data product with reduced cloud contamination. Observations from the Spinning Enhanced Visible and Infra-red Imager (SEVIRI), onboard the European Meteosat Second Generation (MSG) satellite, are used in this study to monitor tropical region vegetation dynamics. The SEVIRI data we used contain observations of land surface at 30-minute time intervals. We used top of atmosphere (TOA) reflectance values from the spectral bands of red (0.635um), NIR (0.81um) and SWIR (1,64 um) and other satellite geometry information to calculate NDVI, angular corrected NDVI and land surface water index, i.e., LSWI = (RNIR-RSWIR)/(RNIR+RSWIR), at 30-minute time intervals for the year 2009. We generated daily, weekly and monthly NDVI and LSWI based on maximum NDVIs. We examined the pattern of cloud occurrence and precipitation and the phenology of green vegetation in Amazon and center Africa regions by dividing each region into the south and north part of the equator. It is found that tropical regions may have 4 times or less clear-sky observations per day while other regions can have more than 10 times of good observations per day. Amazon regions have less chance to get clear-sky observations than center African regions. During the Amazon rain/wet season, some areas cannot get even one good observation per day. It is also found that NDVI seasonality (vegetation growth) is controlled by local precipitation. However, forest NDVI in Amazon has an opposite seasonal cycle against rainfall, which is consistent with MODIS NDVI data. High NDVI corresponds to high LSWI. Tropical forests generally have LSWI value larger than 0. However, the seasonal curve of LSWI is very flat (flatter than the NDVI curve) in Amazon forests, indicating that LSWI is insensitive to drought in this region. In contrast, LSWI is sensitive to wet/dry conditions in Africa, especially in savannas systems, suggesting that LSWI can be served as a drought index in most regions except in tropical forests.

Tian, Y.; Zhou, L.; Romanov, P.; Yu, Y.; Ek, M. B.

2012-12-01

282

Use of Multi-Year MODIS Phenological Data Products to Detect and Monitor Forest Disturbances at Regional and National Scales  

NASA Technical Reports Server (NTRS)

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.

Spruce, Joseph; Hargrove, William W.; Gasser, Jerry; Smoot, James; Ross, Kenton

2010-01-01

283

Impact of fiddler crabs ( Uca spp.) on rates and pathways of benthic mineralization in deposited mangrove shrimp pond waste  

Microsoft Academic Search

The impact of fiddler crabs (Uca spp.) on benthic mineralization rates and pathways in deposits of shrimp pond waste (SPW) with planted mangrove trees (Rhizophora apiculata) were determined in the Ranong mangrove forest, Thailand. Sediment metabolism, measured as CO2 flux, increased by 2- to 3-fold when either fiddler crabs or mangrove trees were present compared to control plots. Sulfate reduction

Ole Ilsøe Nielsen; Erik Kristensen; Donald J. Macintosh

2003-01-01

284

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...

285

NASA LCLUC Program: An Integrated Forest Monitoring System for Central Africa  

NASA Technical Reports Server (NTRS)

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).

Laporte, Nadine; LeMoigne, Jacqueline; Elkan, Paul; Desmet, Olivier; Paget, Dominique; Pumptre, Andrew; Gouala, Patrice; Honzack, Miro; Maisels, Fiona

2004-01-01

286

Project Of Investigation About Growth Of Afforestation Mangrove In Thailand  

NASA Astrophysics Data System (ADS)

At the mangrove which was played back artificially by intended afforestation it designates that related characteristic of growth circumstance and growth environment of the mangrove plant which is grown is evaluated as purpose of this study. Revival of the mangrove in Thailand with afforestation makes the ecosystem revive which consists simultaneously with the mangrove, makes the fishing industry profit at neighborhood possible, makes the life of the people of the locale rich. In addition, the mangrove carries out the role of the anti wave forest, the case of the Sumatra open sea earthquake makes the damage decrease by the tidal wave. The people of the locale re-have recognized concerning the inevitability of the mangrove. Difference has occurred in the amount of mangrove growth depending upon the growth place, the fact that these causes are investigated is something which urges the growth of the efficient mangrove at the time of future afforestation being active. In addition, also comparison of growth circumstance of the mangrove due to natural growth and the mangrove due to afforestation becomes the important research resource. Concretely, it measures growth circumstance (height of tree and diameter etc.) and also, growth environment (the amount of solar radiation, salinity density in substrate and tidal change etc.) and evaluate both correlations. As for evaluation of growth environment of the afforestation mangrove we should evaluate with central value. Because of that, there is a necessity which executes amount of growth measurement with statistical technique. Therefore, with the amount of growth measurement with lumbering, it is unsuitable to the measurement on this study. Regarding this subject of study, growth investigation of the group of trees is executed making use of non destructive physical amount (height of tree and diameter etc.) measurement. It measures at several dozen threes in plural afforestation area, evaluates the growth environment of each afforestation mangrove and the related characteristic of growth circumstance.

Ibuki, R.

2007-12-01

287

Analytical and numerical simulation of tsunami mitigation by mangroves in Penang, Malaysia  

NASA Astrophysics Data System (ADS)

The Andaman tsunami that occurred on 26 December 2004 killed about a quarter million people worldwide, of which 52 deaths happened in Penang, Malaysia. Mangrove forests fringing the shallow coastal seas of Penang Island and northwest of Peninsular Malaysia have been credited to have played a role in mitigating the tsunami waves. It is therefore relevant to assess the role of mangroves in tsunami mitigation by analytical model and numerical simulations. The role of mangrove forest in reducing tsunami wave energy, heights and velocities are simulated by the incorporation of the Morison Equation to represent friction provided by the mangrove forest for the coasts of Penang. Wave heights and velocities can be reduced in the presence of mangrove. However the degree of reduction varies significantly depending on several factors such as wave period and wavelength as well as mangrove characteristics including forest widths and density. For a wave of 10 km wavelength, with wave height and velocity of 1.0 m and 1.0 m/s, respectively at the shore without a mangrove forest, then a mangrove forest of 500 m width may provide a reduction ratio for wave height and wave velocity of about 0.55 and 0.50, respectively.

Teh, Su Yean; Koh, Hock Lye; Liu, Philip Li-Fan; Ismail, Ahmad Izani Md.; Lee, Hooi Ling

288

Biology of mangroves and mangrove Ecosystems  

Microsoft Academic Search

Mangroves are woody plants that grow at the interface between land and sea in tropical and sub-tropical latitudes where they exist in conditions of high salinity, extreme tides, strong winds, high temperatures and muddy, anaerobic soils. There may be no other group of plants with such highly developed morphological and physiological adaptations to extreme conditions.Because of their environment, mangroves are

K. Kathiresan; B. L. Bingham

2001-01-01

289

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

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

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

290

Disentangling the effects of climate, species, and management on growth and mortality of southeast Asian mangroves  

NASA Astrophysics Data System (ADS)

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.

Baker, Patrick; Bunyavejchewin, Sarayudh; Robinson, Andrew

2013-04-01

291

Monitoring Strategies for REDD+: Integrating Field, Airborne, and Satellite Observations of Amazon Forests  

NASA Technical Reports Server (NTRS)

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.

Morton, Douglas; Souza, Carlos, Jr.; Souza, Carlos, Jr.; Keller, Michael

2012-01-01

292

Monitoring environmental state of Alaskan forests with AIRSAR  

NASA Technical Reports Server (NTRS)

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. The implications of using SAR to monitor canopy phenological state are addressed.

Mcdonald, Kyle C.; Way, Jobea; Rignot, Eric; Williams, Cindy; Viereck, Les; Adams, Phylis

1992-01-01

293

Interagency Collaborators Develop and Implement ForWarn, a National, Near Real Time Forest Monitoring Tool  

NASA Technical Reports Server (NTRS)

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.

Underwood, Lauren

2013-01-01

294

Cumulative impacts of hurricanes on Florida mangrove ecosystems: Sediment deposition, storm surges and vegetation  

USGS Publications Warehouse

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.

Smith, III, T. J.; Anderson, G. H.; Balentine, K.; Tiling, G.; Ward, G. A.; Whelan, K. R. T.

2009-01-01

295

Mosquitoes of the mangrove forests of India: Part 3--Andaman and Nicobar Islands, including an update on the mosquito fauna of the islands.  

PubMed

ABSTRACT. Fifty-three mosquito species belonging to 20 subgenera and 18 genera--Aedes, Anopheles, Armigeres, Culex, Downsiomyia, Finlaya, Heizmannia, Kenknightia, Lorrainea, Lutzia, Ochlerotatus, Orthopodomyia, Rhinoskusea, Stegomyia, Toxorhynchites, Tripteroides, Uranotaenia, and Verrallina--were recorded in the mangroves of Andaman and Nicobar Islands, India, in collections made during May and June 2001. Larvae of 43 species were collected from different mangrove habitats. Together with collections made in nonmangrove areas, 83 species in 22 subgenera and 20 genera in total were recorded of which 33 species are new records for the Andaman and Nicobar Islands. Rhinoskusea wardi, Fl. flavipennis, and Ve. consonensis are 3 new country records for India. Collections included topotype specimens of St. seampi. Together with species known from earlier records, the mosquito fauna of Andaman and Nicobar Islands is updated to 107 species in 23 subgenera and 24 genera. PMID:17067033

Rajavel, A R; Natarajan, R

2006-09-01

296

Adaptive Weighted Fusion Algorithm for Monitoring System of Forest Fire Based on Wireless Sensor Networks  

Microsoft Academic Search

Forest fires have drawn increasing attention in recent years due to their tremendous effects on environment, humans and wild life, ecosystem function, weather, and climate. Accurate monitoring of forest fires field is important since it contributes in fire effects assessing and controlling. This study attempts to apply adaptive weighted fusion algorithm in a wireless sensor networks (WSNs) system for the

Guang Lu; Wei Xue

2010-01-01

297

Inorganic and organic carbon biogeochemistry in the Gautami Godavari estuary (Andhra Pradesh, India) during pre-monsoon: The local impact of extensive mangrove forests  

Microsoft Academic Search

The distribution and sources of organic and inorganic carbon were studied in the Gautami Godavari estuary (Andhra Pradesh, India) and in a mangrove ecosystem in its delta during pre-monsoon. In the oligohaline and mesohaline section (salinity 0-15) of the estuary, internal production of total alkalinity (TAlk) and dissolved inorganic carbon (DIC) was recorded, and the delta13CDIC profile suggests that carbonate

Steven Bouillon; Michel Frankignoulle; Frank Dehairs; Branko Velimirov; Alexander Eiler; Gwenaël Abril; Henri Etcheber; Alberto Vieira Borges

2003-01-01

298

Beyond forest carbon  

NASA Astrophysics Data System (ADS)

The preservation of forests, both on land and in mangrove swamps, has received much attention in the move to protect biological carbon stores. Less conspicuous communities of organisms deserve some scrutiny, too.

2012-07-01

299

Food web structure in exotic and native mangroves: A Hawaii-Puerto Rico comparison  

USGS Publications Warehouse

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.

Demopoulos, A. W. J.; Fry, B.; Smith, C. R.

2007-01-01

300

Réseaux trophiques et fonctionnement trophodynamique de l'ichtyofaune des mangroves de Nouvelle-Calédonie  

Microsoft Academic Search

Fish communities from geomorphologically different mangrove forests showed distinct trophic structures. A mangrove area located near fringing reefs (Bouraké) was dominated by large invertebrate (> 2 mm) feeders (40.7 % of total wet weight of the fish fauna) and herbivores (26.7 %) whilst an estuarine mangrove (Ouenghi) was characterized by detritus feeders (28.2 %), piscivorous (18.2 %) and large invertebrate feeders (17.9 %). In spite of

Pierre Thollot; Michel Kulbicki; Mireille Harmelin-Vivien

1999-01-01

301

Mangrove loss leads to fish hyperutilization of seagrass beds in a UNESCO biosphere reserve.  

PubMed

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

Bologna, P A X

2014-05-01

302

Cumulative impacts of hurricanes on Florida mangrove ecosystems: Sediment deposition, storm surges and vegetation  

Microsoft Academic Search

Hurricanes have shaped the structure of mangrove forests in the Everglades via wind damage, storm surges and sediment deposition.\\u000a Immediate effects include changes to stem size-frequency distributions and to species relative abundance and density. Long-term\\u000a impacts to mangroves are poorly understood at present. We examine impacts of Hurricane Wilma on mangroves and compare the\\u000a results to findings from three previous

Thomas J. Smith III; Gordon H. Anderson; Karen Balentine; Ginger Tiling; Greg A. Ward; Kevin R. T. Whelan

2009-01-01

303

Biodegradation of Enteromorpha prolifera by mangrove degrading microcommunity with physical–chemical pretreatment  

Microsoft Academic Search

The bacteria involved in the biodegradation of Enteromorpha prolifera (EP) are largely unknown, especially in offshore mangrove environments. In order to obtain the bacterial EP-degrading communities,\\u000a sediments from a typical mangrove forest were sampled on the roots of mangrove in Dongzhai Port (Haikou, China). The sediments were enriched with crude EP powders as the sole carbon source. The bacterial composition

Chao Zhao; Lingwei Ruan

304

Monitoring dry deposition of gases and particles over a forest  

NASA Astrophysics Data System (ADS)

Dry deposition fluxes of acidifying and eutrophying compounds are continuously determined at Speulder forest, a Douglas fir site in the centre of the Netherlands. The monitoring equipment, installed on a 36-m high tower, consists of a sonic anemometer, a cup anemometer, a wind vane, a Bowen ratio system, three temperature/r.h. sensors, and gas analyzers to measure gradients of SO 2, NO x and NH 3 and concentrations of HCl, HNO 2 and HNO 3. Particles are sampled in two size ranges (<2.5 mm and 2.5-10 mm) on filters, which are analysed for acidifying components and basic cations. Fluxes of SO 2, NO x and NH 3 are determined with the gradient method, while fluxes of the other components are estimated with the inferential method. Parameterizations of the surface resistance ( Rc) for gases are derived from measurements obtained during periods that meet criteria with respect to homogeneous fetch, stationary flow, etc. Parameterized Rc values are used to estimate fluxes during periods that don't fulfil these demands. In this way, yearly average fluxes can be determined. In 1995, the total deposition fluxes of SO x(=SO 2+SO 42-), NO y(=NO x+NO 3-+HNO 2+HNO 3) and NH x, (=NH 3+NH 4+) were 450, 630 and 1620 eq. ha -1 a -1, respectively.

Mennen, M. G.; van Putten, E. M.; Uiterwijk, J. W.; Hogenkamp, J. E. M.; Wiese, C. J.; Draaijers, G.; Erisman, J. W.; Otjes, R. P.; Wyers, G. P.

1996-12-01

305

Microbial diversity in Brazilian mangrove sediments - a mini review.  

PubMed

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

Ghizelini, Angela Michelato; Mendonça-Hagler, Leda Cristina Santana; Macrae, Andrew

2012-10-01

306

Canopy gaps formed by mangrove trimming: an experimental test of impact on litter fall and standing litter stock in Southwest Florida (USA)  

Microsoft Academic Search

Mangroves in Florida (USA) are subject to horticultural pruning that may increase the size of canopy gaps and alter rates of litter production and accumulation. Mangrove canopy gap formation is a common phenomenon, known to alter abiotic conditions near the forest floor. Using a series of field experiments in Rookery Bay, Florida, the effects of mangrove trimming on canopy density,

William L. Ellis; Susan S. Bell

2004-01-01

307

Potential for Monitoring Snow Cover in Boreal Forests by Combining MODIS Snow Cover and AMSR-E SWE Maps.  

National Technical Information Service (NTIS)

Monitoring of snow cover extent and snow water equivalent (SWE) in boreal forests is important for determining the amount of potential runoff and beginning date of snowmelt. The great expanse of the boreal forest necessitates the use of satellite measurem...

D. K. Hall G. A. Riggs J. L. Foster

2009-01-01

308

Monitoring forest land from high altitude and from space  

NASA Technical Reports Server (NTRS)

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.

1972-01-01

309

Monitoring forest land from high altitude and from space  

NASA Technical Reports Server (NTRS)

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.

1971-01-01

310

Between Land and Sea: Livelihoods and Environmental Changes in Mangrove Ecosystems of Senegal  

Microsoft Academic Search

Unlike the global trend, the area of mangrove forest increased in the estuaries of Low Casamance and Sine-Saloum, Senegal, between 1986 and 2006. We collected multisource data (social and spatial) and applied a mix of qualitative and quantitative analytical methods to investigate the human–mangrove interactions during this period and to understand the causes of the observed increase. Our research demonstrates

Giulia Conchedda; Eric F. Lambin; Philippe Mayaux

2011-01-01

311

Simulating cryptic movements of a mangrove crab: Recovery phenomena after small scale fishery  

Microsoft Academic Search

The semi-terrestrial burrowing crab Ucides cordatus is an important ecological component and economic resource of Brazilian mangrove forests. The crab population of the Caeté peninsula (the location of our study site) has been exploited for the last 40 years. Recovery of fished areas by crabs from non-fished areas under the roots of the mangrove tree Rhizophora mangle was hypothesized to

Cyril Piou; Uta Berger; Hanno Hildenbrandt; Volker Grimm; Karen Diele; Coralie D’Lima

2007-01-01

312

Comparison of NASA OMI and MLS Ozone Products with US Forest Service Ground-based Ozone Monitoring Data for US Forest Service Air Quality / Forest Management Decision Support  

NASA Astrophysics Data System (ADS)

Tropospheric ozone, formed when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react with sunlight, is a significant threat to the health of US National Forests. Approximately one third of ozone is absorbed by plants during the uptake of carbon dioxide. This increases the vegetation's susceptibility to drought, beetle infestation, and wildfire. Currently the US Forest Service has ground monitoring stations sparsely located across the country. This project looks specifically at the area surrounding several Class I Wilderness Areas in the Appalachian region. These areas are the highest priority for protection from air pollutants. The Forest Service must interpolate ozone concentrations for areas between these monitoring stations. Class I Wilderness Areas are designated by the Forest Service and are defined as a total 5000 acres or greater when the Clean Air Act was passed in 1977. This Act mandated that the EPA create national ambient air quality standards (NAAQS) for six major air pollutants including ground-level ozone. This project assessed the feasibility of incorporating NASA ozone data into Forest Service ozone monitoring in an effort to enhance the accuracy and precision of ozone exposure measurements in Class I Wilderness Areas and other federally managed lands in order to aid in complying with the Clean Air Act of 1977. This was accomplished by establishing a method of comparison between a preliminary data product produced at the Goddard Space Flight Center that uses OMI/MLS data to derive global tropospheric ozone measurements and Forest Service ozone monitoring station measurements. Once a methodology for comparison was established, statistical comparisons of these data were performed to assess the quantitative differences.

Barrett, S.; Brooks, A.; Moussa, Y.; Spencer, T.; Thompson, J.

2013-12-01

313

Study of remote sensing monitoring of dynamic change of the Loess Plateau forest resources  

NASA Astrophysics Data System (ADS)

Taking for example Daning County, a key pilot area of ``the Three North Protection Forest Project'' in China's Loess Plateau, this article is to explore the method of using remote sensing technology to monitoring the dynamic change information of forest vegetation. It uses LANDSAT TM, CBERS-1 data and aerial remote sensing and ground investigation to monitoring the dynamic change of forest vegetation information of Daning County in three different periods - 1978, 1987 and 2000. The results of the research prove that, this method is worth widely popularized, by which the dynamic change information of the forest vegetation can be monitored simply and quickly so as to explore a scientific, rational and effective road for us to rectify the territory of China's Loess Plateau, change the poor physiognomy of this area, improve the ecological environment and promote the development of national economy.

Yuliang, Qiao; Ying, Wang; Junyou, Tang

314

GHG monitoring over Paris megacity and Orléans forest  

NASA Astrophysics Data System (ADS)

In a growing world with more than 7 billion inhabitants and big emerging countries such as China, Brazil and India, emissions of anthropogenic pollutants and greenhouse gases (GHGs) are increasing continuously. Their monitoring and control in megacities have become a major challenge for scientists and public health authorities in environmental research area. The ground-based Fourier transform spectrometer (QualAir FTS[a], model IFS 125HR) of the QualAir platform located in downtown Paris at University Pierre et Marie Curie (UPMC), is a scientific research instrument dedicated to the survey of greenhouse gases (GHGs) and urban air quality. Equipped with a sun-tracker, the remote sensing QualAir FTS relies on solar infrared absorption for monitoring trace gas concentrations and their variability in the Ile-de-France region[b]. Concentrations of atmospheric GHGs, especially CO2, CH4 and N2O, are retrieved by the radiative transfer model PROFFIT[c]. Because Paris is the third largest European megacity, the QualAir FTS can provide new and complementary measurements as compared to existing ground-based FTS network stations (NDACC and TCCON) located in unpolluted environments, such as the TCCON-Orléans station[d] situated in the forest of Orléans (100 km south of Paris). In the effort to integrate QualAir FTS into the TCCON network, simultaneous FTS measurements of GHGs at Paris and Orléans have been performed. We will emphasize on comparisons of CO2 from these two sites. Our comparison will be completed by high-resolved direct CO2 modeling outputs from the Meso-NH model, and ground in situ measurements at different sites (Orléans/Trainou, Paris/Jussieu, Paris/Eiffel Tower). Parts of the data were acquired in the framework of the French CO2-MEGAPARIS project[e, f], whose main goal is to quantify CO2 emissions from the Paris area. The present data intercomparison will help to reduce uncertainties in carbon cycle models and to better characterize regional GHG fluxes, especially with respect to anthropogenic emission sources (urban versus rural) and trends. References: [a] Té et al., J. Atmos. Oceanic Technol., 29, 911-921, 2012 [b] Té et al., Rev. Sci. Instrum., 81, 103102, 2010 [c] Hase et al., JQSRT, 87, 25-52, 2004 [d] https://tccon-wiki.caltech.edu/Sites/Orleans [e] http://co2-megaparis.lsce.ipsl.fr/ [f] Xueref-Remy et al., Abstract n°A13F-0277, AGU Fall Meeting 2010, San Francisco, USA

Te, Y. V.; Jeseck, P.; Zanon, T.; Boursier, C.; Janssen, C.; Deutscher, N. M.; Warneke, T.; Notholt, J.; Lac, C.; Dieudonné, E.; Lopez, M.; Schmidt, M.; Xueref-remy, I. C.

2012-12-01

315

Global climate change mitigation and sustainable forest management--The challenge of monitoring and verification  

SciTech Connect

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.

Makundi, Willy R.

1997-12-31

316

Spatial heterogeneity and kinetic regulation of arsenic dynamics in mangrove sediments: the Sundarbans, Bangladesh.  

PubMed

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. PMID:22834808

Sumon, Mahmud H; Hossain, Mahmud; Williams, Paul N; Mestrot, Adrien; Norton, Gareth J; Deacon, Claire M; Meharg, Andrew A

2012-08-21

317

Taiga Forest Stands and SAR: Monitoring for Subarctic Global Change.  

National Technical Information Service (NTIS)

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 Fairba...

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

1992-01-01

318

MONITORING IN SUPPORT OF THE PACIFIC NORTHWEST FOREST PLAN: A REPORT ON REQUIREMENTS AND KEY QUESTIONS  

EPA Science Inventory

This document summarizes the monitoring requirements identified in the Record of Decision (ROD) for the Pacific Northwest Forest Plan and presents the key questions the future monitoring program should strive to answer. he key questions, developed from the standards and guideline...

319

Co2 emission from mangroves' surrounding waters  

Microsoft Academic Search

The partial pressure of CO2 (pCO2) was obtained at daily and weekly time scales in the waters surrounding mangrove forests in Papua New Guinea (Nagada Creek), the Bahamas (Norman's Pond) and India (Gaderu Creek, delta of the Gautami Godavari estuary). The pCO2 values range from near atmospheric equilibrium to 4800 :atm. From these and also published data, we can conclude

A. V. Borges; B. Delille; M. Frankignoulle

2003-01-01

320

An application of remote sensing data in mapping landscape-level forest biomass for monitoring the effectiveness of forest policies in northeastern China.  

PubMed

Monitoring the dynamics of forest biomass at various spatial scales is important for better understanding the terrestrial carbon cycle as well as improving the effectiveness of forest policies and forest management activities. In this article, field data and Landsat image data acquired in 1999 and 2007 were utilized to quantify spatiotemporal changes of forest biomass for Dongsheng Forestry Farm in Changbai Mountain region of northeastern China. We found that Landsat TM band 4 and Difference Vegetation Index with a 3 × 3 window size were the best predictors associated with forest biomass estimations in the study area. The inverse regression model with Landsat TM band 4 predictor was found to be the best model. The total forest biomass in the study area decreased slightly from 2.77 × 10(6) Mg in 1999 to 2.73 × 10(6) Mg in 2007, which agreed closely with field-based model estimates. The area of forested land increased from 17.9 × 10(3) ha in 1999 to 18.1 × 10(3) ha in 2007. The stabilization of forest biomass and the slight increase of forested land occurred in the period following implementations of national forest policies in China in 1999. The pattern of changes in both forest biomass and biomass density was altered due to different management regimes adopted in light of those policies. This study reveals the usefulness of the remote sensing-based approach for detecting and monitoring quantitative changes in forest biomass at a landscape scale. PMID:23793545

Wang, Xinchuang; Shao, Guofan; Chen, Hua; Lewis, Bernard J; Qi, Guang; Yu, Dapao; Zhou, Li; Dai, Limin

2013-09-01

321

An Application of Remote Sensing Data in Mapping Landscape-Level Forest Biomass for Monitoring the Effectiveness of Forest Policies in Northeastern China  

NASA Astrophysics Data System (ADS)

Monitoring the dynamics of forest biomass at various spatial scales is important for better understanding the terrestrial carbon cycle as well as improving the effectiveness of forest policies and forest management activities. In this article, field data and Landsat image data acquired in 1999 and 2007 were utilized to quantify spatiotemporal changes of forest biomass for Dongsheng Forestry Farm in Changbai Mountain region of northeastern China. We found that Landsat TM band 4 and Difference Vegetation Index with a 3 × 3 window size were the best predictors associated with forest biomass estimations in the study area. The inverse regression model with Landsat TM band 4 predictor was found to be the best model. The total forest biomass in the study area decreased slightly from 2.77 × 106 Mg in 1999 to 2.73 × 106 Mg in 2007, which agreed closely with field-based model estimates. The area of forested land increased from 17.9 × 103 ha in 1999 to 18.1 × 103 ha in 2007. The stabilization of forest biomass and the slight increase of forested land occurred in the period following implementations of national forest policies in China in 1999. The pattern of changes in both forest biomass and biomass density was altered due to different management regimes adopted in light of those policies. This study reveals the usefulness of the remote sensing-based approach for detecting and monitoring quantitative changes in forest biomass at a landscape scale.

Wang, Xinchuang; Shao, Guofan; Chen, Hua; Lewis, Bernard J.; Qi, Guang; Yu, Dapao; Zhou, Li; Dai, Limin

2013-09-01

322

Mangrove Key Islets  

USGS Multimedia Gallery

Beyond the mangrove key islets that make up the Ten Thousand Islands, lies the Gulf of Mexico. The Ten Thousand Islands are comprised of hundreds of mangrove islands that extend northward from the northwest corner of Everglades National Park. These uninhabited islands stretch for 60-miles al...

2009-06-17

323

Sulphur-oxidizing and sulphate-reducing communities in Brazilian mangrove sediments.  

PubMed

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. PMID:24033859

Varon-Lopez, Maryeimy; Dias, Armando Cavalcante Franco; Fasanella, Cristiane Cipolla; Durrer, Ademir; Melo, Itamar Soares; Kuramae, Eiko Eurya; Andreote, Fernando Dini

2014-03-01

324

Continental scale patterns in mangrove litter fall  

Microsoft Academic Search

Litter fall was monitored in stands of the mangrove species Rhizophora stylosa Griff., Ceriops tagal (Perr.) C. B. Robinson and Avicennia marina (Forsk.), Vierh. at approximately monthly intervals over a single annual cycle at selected locations around the coastline of Australia and throughout the distribution of each species. Concurrent data were obtained from a single location near Port Moresby in

John S. Bunt

1995-01-01

325

FRAMEWORK FOR ASSESSING EFFECTS OF GLOBAL CLIMATE CHANGE ON MANGROVE ECOSYSTEMS  

EPA Science Inventory

Mangrove ecosystems perhaps represent the most diverse combination of floral, faunal and physical elements among coastal habitats. angrove forests are globally widespread in the tropics and subtropics and provide a dynamic interface between the sea and the land. angrove ecosystem...

326

Kelp forest monitoring. Channel Islands National Park (1990 annual report). Final technical report  

SciTech Connect

The 1990 results of the Channel Islands National Park Kelp Forest Monitoring Project are described in this report. Sixty-eight species of algae, fish , and invertebrates were monitored annually at 16 permanent sites around the five islands within the park. Survey techniques utilized SCUBA and surface-supplied-air, and included quadrats, band transects, random point contacts, size frequencies, fish and video transects, photogrammetric plots, size frequency measurements, and species list surveys. In 1990, eight sites had healthy kelp forests, while three others had remnants or signs of a developing forest, though dominated by purple sea urchins. Four sites were dominated by purple sea urchins and one was dominated by red sea urchins. Four sites had high to moderate densities of white sea urchins, but two of those had dense kelp forests over most of the transect.

Richards, D.; Avery, W.; Kushner, D.

1993-06-01

327

Monitoring the Extent of Forests on National to Global Scales  

NASA Astrophysics Data System (ADS)

Information on forest extent and change is important for many purposes, including understanding the global carbon cycle and managing natural resources. International statistics on forest extent are generated using many different sources often producing inconsistent results spatially and through time. Results will be presented comparing forest extent derived from the recent global Food and Agricultural Organization's (FAO) FRA 2000 report with products derived using wall-to-wall Landsat, AVHRR and MODIS data sets. The remotely sensed data sets provide consistent results in terms of total area despite considerable differences in spatial resolution. Although the location of change can be satisfactorily detected with all three remotely sensed data sets, reliable measurement of change can only be achieved through use of Landsat-resolution data. Contrary to the FRA 2000 results we find evidence of an increase in deforestation rates in the late 1990s in several countries. Also we have found evidence of considerable changes in some countries for which little or no change is reported by FAO. The results indicate the benefits of globally consistent analyses of forest cover based on multiscale remotely sensed data sets rather than a reliance on statistics generated by individual countries with very different definitions of forest and methods used to derive them.

Townshend, J.; Townshend, J.; Hansen, M.; DeFries, R.; DeFries, R.; Sohlberg, R.; Desch, A.; White, B.

2001-05-01

328

CLIMATE DATA AND ANALYSIS FOR THE NEW ENGLAND FOREST HEALTH MONITORING PROJECT (NEFHM/EMAP FORESTS)  

EPA Science Inventory

This paper describes the development of climatological information products to support ecological data collection and analysis. Characteristics of climatological persistence and recurrence that are critical to New England forest health and productivity are identified. he appropri...

329

Chemical ecology of red mangroves, Rhizophora mangle, in the Hawaiian Islands  

USGS Publications Warehouse

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.

Fry, Brian; Cormier, Nicole

2011-01-01

330

Importance of different carbon sources for macroinvertebrates and fishes of an interlinked mangrove-mudflat ecosystem (Tanzania)  

NASA Astrophysics Data System (ADS)

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 ? 13C was present between primary producers from mangrove and mudflat habitats. Macroinvertebrates revealed a gradient in their ? 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.

Kruitwagen, G.; Nagelkerken, I.; Lugendo, B. R.; Mgaya, Y. D.; Bonga, S. E. Wendelaar

2010-08-01

331

Pacific northwest region vegetation and inventory monitoring system. Forest Service research paper  

SciTech Connect

A grid sampling strategy was adopted for broad-scale inventory and monitoring of forest and range vegetation on National Forest System lands in the Pacific Northwest Region, USDA Forest Service. This paper documents the technical details of the adopted design and discusses alternative sampling designs that were considered. The design is flexible and can be used with many types of maps. The theory of point and change estimation is described, as well as estimates of variation that assess the statistical precision of estimates.

Max, T.A.; Schreuder, H.T.; Hazard, J.W.; Oswald, D.D.; Teply, J.

1996-12-01

332

Recent accretion in mangrove ecosystems based on 137 Cs and 210 Pb  

Microsoft Academic Search

Accretion rates were measured in fringe and basin mangrove forests in river and tidally dominated sites in Terminos Lagoon,\\u000a Mexico, and a basin mangrove forest in Rookery Bay, Florida, USA. Accretion rates were determined using the radionuclides210Pb and137Cs. Consolidation-corrected accretion rates for the Rookery Bay cores, ranged from 1.4 to 1.7 mm yr?1, with an average rate of 1.6 mm

James C. Lynch; John R. Meriwether; Brent A. McKee; Francisco Vera-Herrera; Robert R. Twilley

1989-01-01

333

Sediment and Nutrient Deposition Associated with Hurricane Wilma in Mangroves of the Florida Coastal Everglades  

Microsoft Academic Search

The distribution of mangrove biomass and forest structure along Shark River estuary in the Florida Coastal Everglades (FCE)\\u000a has been correlated with elevated total phosphorus concentration in soils thought to be associated with storm events. The\\u000a passage of Hurricane Wilma across Shark River estuary in 2005 allowed us to quantify sediment deposition and nutrient inputs\\u000a in FCE mangrove forests associated

Edward Castañeda-Moya; Robert R. Twilley; Victor H. Rivera-Monroy; Keqi Zhang; Stephen E. Davis; Michael Ross

2010-01-01

334

Elevated rates of organic carbon, nitrogen, and phosphorus accumulation in a highly impacted mangrove wetland  

NASA Astrophysics Data System (ADS)

effect of nutrient enrichment on mangrove sediment accretion and carbon accumulation rates is poorly understood. Here we quantify sediment accretion through radionuclide tracers to determine organic carbon (OC), total nitrogen (TN), and total phosphorus (TP) accumulation rates during the previous 60 years in both a nutrient-enriched and a pristine mangrove forest within the same geomorphological region of southeastern Brazil. The forest receiving high nutrient loads has accumulated OC, TN, and TP at rates that are fourfold, twofold, and eightfold respectively, higher than those from the undisturbed mangrove. Organic carbon and TN stable isotopes (?13C and ?15N) reflect an increased presence of organic matter (OM) originating with either phytoplankton, benthic algae, or another allochthonous source within the more rapidly accumulated sediments of the impacted mangrove. This suggests that the accumulation rate of OM in eutrophic mangrove systems may be enhanced through the addition of autochthonous and allochthonous nonmangrove material.

Sanders, Christian J.; Eyre, Bradley D.; Santos, Isaac R.; Machado, Wilson; Luiz-Silva, Wanilson; Smoak, Joseph M.; Breithaupt, Joshua L.; Ketterer, Michael E.; Sanders, Luciana; Marotta, Humberto; Silva-Filho, Emmanoel

2014-04-01

335

Ecosystem development after mangrove wetland creation: plant-soil change across a 20-year chronosequence  

USGS Publications Warehouse

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 layer (0-10 cm), SOM, TC, and TN increased with created wetland site age simultaneously with mangrove forest growth. The rate of created wetland soil C accumulation was comparable to literature values for natural mangrove wetlands. Notably, the time to equivalence for the upper soil layer of created mangrove wetlands appears to be faster than for many other wetland ecosystem types. Collectively, our findings characterize the rate and trajectory of above- and below-ground changes associated with ecosystem development in created mangrove wetlands; this is valuable information for environmental managers planning to sustain existing mangrove wetlands or mitigate for mangrove wetland losses.

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

336

Status of and Attitudes Toward Aquatic Macroinvertebrate Monitoring on National Forests and Districts of the Bureau of Land Management.  

National Technical Information Service (NTIS)

A survey was mailed to all forests in the USDA Forest Service's National Forest System (NFS) and all Districts of the Bureau of Land Management (BLM) to determine the status of and attitudes toward aquatic macroinvertebrate monitoring (AMM). Sixty-five pe...

T. R. Angradi M. R. Vinson

1995-01-01

337

Mapping and Monitoring Forest Degradation in Indonesia Using Landsat time-series data sets from 1990 to 2010  

NASA Astrophysics Data System (ADS)

Tropical deforestation and forest degradation accounts for over 18% of CO2 emissions globally. Timely and accurate information on forest extent and change is required for monitoring such changes to tropical forest. Remote sensing is perhaps the only effective means for tropical forest exploitation monitoring. Indonesian forests account for 2.3% of global forest cover, but monitoring in Indonesia faces challenges due to (i) unavailability of cloud free days due to climatic conditions, (ii) rapid reestablishment of tree cover by timber plantations, palm estates and subsequent secondary re-growth, and (iii) uncertainties in fractional land cover types in uneven terrain. A hybrid approach is presented here where an Intact Forest Landscape methodology, based on GIS-based buffering of observable disturbances is coupled with a per pixel mapping of old growth forest stands. Forest cover loss from 1990 to 2010 is mapped independently and trends in intact and degraded forest are quantified. Results advance the monitoring of forest cover and the carbon cycle required for UNFCCC REDD objectives to mitigate climate change by reducing carbon emissions from tropical forest exploitation.

Margono, B. A.; Potapov, P. V.; Hansen, M. C.

2011-12-01

338

Sample project: establishing a global forest monitoring capability using multi-resolution and multi-temporal remotely sensed data sets  

USGS Publications Warehouse

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.

Hansen, Matt; Stehman, Steve; Loveland, Tom; Vogelmann, Jim; Cochrane, Mark

2009-01-01

339

Evaluation of satellite change detection methods for monitoring forest harvest and silvicultural activity in Maine industrial forests  

NASA Astrophysics Data System (ADS)

Change detection is a major application of satellite remote sensing. The idea is to analyze change in spectral patterns over a particular geographic area at different points of time. The information might be gathered by different satellite platforms (multi-sensor), in various wavebands (multi- spectral) and on several acquisition dates (multi-temporal). For forestry field applications, change detection might provide useful information for forest resources management, inventory, evaluation, planning, and monitoring. This study incorporated a multi-temporal approach for detecting forest change due to clearcut, partial cut, and release operation treatments in a Maine study area. Most forest change detection studies include only two dates of imagery. However, in this investigation, three date satellite images from 1983, 1988 and 1991 were examined simultaneously in a single step analysis approach. Two change detection methods, the Normalized Difference Vegetation Index (NDVI) and the Principal Components Analysis (PCA) were evaluated and a new method, Principal Factor Analysis (PFA) was introduced. A maximum likelihood classification algorithm was used to categorize change/no change events and the results were compared to a forest stand exam and history database. The Khat statistic was chosen as the criteria to evaluate the accuracy of each classification method while pairwise significance tests were constructed to compare results between methods. The Standardized variant of Principal Factor Analysis (SPFA) produced the best results followed by Principal Components Analysis and Normalized Difference Vegetation index.

Pangaribuan, Humala P.; Sader, Steven A.

1997-09-01

340

Mangrove habitat partitioning by Ucides cordatus (Ucididae): effects of the degree of tidal flooding and tree-species composition during its life cycle  

NASA Astrophysics Data System (ADS)

Environmental factors strongly affect mangrove crabs, and some factors modulate population structure and habitat partitioning during the crabs' life cycle. However, the effect of these environmental factors on habitat selection by mangrove crabs is still unknown. We evaluated habitat selection by the mangrove crab Ucides cordatus in mangrove forests with different degrees of predominance of Rhizophora mangle, Laguncularia racemosa or Avicennia schaueriana, two tidal flooding levels (less- and more-flooded), and two biological periods (breeding and non-breeding seasons). Sampling was conducted in four mangrove forests with different influences of these biotic and abiotic parameters. We used the data for sex ratio to explain environmental partitioning by this species. Females predominated in R. mangle mangroves, independently of the biological period (breeding or non-breeding seasons), and males predominated only in the less-flooded L. racemosa mangroves. The flooding level affected the sex ratio of U. cordatus, with a predominance of males in less-flooded mangroves, independently of the biological period; and a gender balance in the more-flooded mangroves only during the breeding season. Outside the breeding season, the largest specimens were recorded in the R. mangle mangroves, but in the breeding season, the largest crabs were recorded in the L. racemosa mangroves with a higher level of flooding. These results suggest that tree-species composition and tidal flooding level can have a significant effect on the habitat partitioning of sexes and sizes of the mangrove crab U. cordatus both during and outside the breeding season.

Wunderlich, A. C.; Pinheiro, M. A. A.

2013-06-01

341

Development of a protocol for monitoring status and trends in forest soil carbon at a national level  

Microsoft Academic Search

The national Forest Health Monitoring (FHM) program requires protocols for monitoring soil carbon contents. In a pilot study, 30 FHM plots loblolly\\/shortleaf (Pinus taeda L.\\/Pinus echinata Mill.) pine forests across Georgia were sampled by horizon and by depth increments. For total soil carbon, approximately 40% of the variance was between plots, 40% between subplots and 20% within subplots. Results by

C. J. Palmer; W. D. Smith; B. L. Conkling

2002-01-01

342

Assessing relatedness and redundancy of forest monitoring and change indicators.  

PubMed

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

Nagendra, Harini

2012-03-01

343

The effect of mangrove reforestation on the accumulation of PCBs in sediment from different habitats in Guangdong, China.  

PubMed

To investigate the influence of mangrove reforestation on the accumulation of PCBs, the concentrations and homologue patterns of polychlorinated biphenyls in surface sediments from different mangrove forests and their adjacent mud flats in Guangdong Province were determined. The total PCB concentrations in the sediments ranged from 3.03 to 46.62 ng g?¹ (dry weight). Differences in the accumulation and distribution of PCBs were found between the mangrove sites and the mud flats. Furthermore, the natural forests and restored mangrove forests of native species showed slight PCB contamination, whereas the exotic species Sonneratia apetala exacerbated the PCB pollution at certain sites. It was suggested that the native mangrove species Kandelia candel and Aegiceras corniculatum could represent good choices for the phytoremediation of PCB contamination. PMID:22704149

Zhao, Bo; Zhou, Yan-Wu; Chen, Gui-Zhu

2012-08-01

344

Measuring Mangrove Type, Structure And Carbon Storage With UAVSAR And ALOS/PALSAR Data  

NASA Astrophysics Data System (ADS)

Mangrove forests provide a great number of ecosystem services ranging from shoreline protection (e.g. against erosion, tsunamis and storms), nutrient cycling, fisheries production, building materials and habitat. Mangrove forests have been shown to store very large amounts of Carbon, both above and belowground, with storage capacities even greater than tropical rainforests. But as a result of their location and economic value, they are among the most rapidly changing landscapes in the World. Mangrove extent is limited 1) in total extent to tidally influenced coastal areas and 2) to tropical and subtropical regions. This can lead to difficulties mapping mangrove type (such as degraded vs non degraded, scrub vs tall, dense vs sparse) because of cloud cover and limited access to high-resolution optical data. To accurately quantify the effect of land use and climate change on tropical wetland ecosystems, we must develop effective mapping methodologies that take into account not only extent, but also the structure and health of the ecosystem. This must be done by including Synthetic Aperture Radar (SAR) data. In this research, we used L-band Synthetic Aperture Radar data from the ALOS/PALSAR and UAVSAR instruments over selected sites in the Americas (Sierpe, Costa Rica and Everglades, Florida)and Asia (Sundarbans). In particular, we used the SAR data in combination with other remotely sensed data and field data to 1) map mangrove extent 2) determine mangrove type, health and adjascent land use, and 3) estimate aboveground biomass and carbon storage for entire mangrove systems. We used different classification methodologies such as polarimetric decomposition, unsupervised classification and image segmentation to map mangrove type. Because of the high resolution of the radar data, and its ability to interact with forest volume, we are able to identify mangrove zones and differentiate between mangroves and other forests/land uses. We also integrated InSAR data (SRTM), spaceborne Lidar (GLAS) and field data, in combination with the SAR data to derive aboveground biomass and carbon storage in mangroves. We successfully produced maps of mangrove extent, type, health and carbon storage by using L-band SAR data. Our results show that both UAVSAR and ALOS/PALSAR data alone are effective datasets for mapping mangrove extent, type and other land use. By combining multiple datasets, we were able to determine mangrove biomass without an upper estimation limit and with low error.

Fatoyinbo, T. E.; Cornforth, W.; Pinto, N.; Simard, M.; Pettorelli, N.

2011-12-01

345

The mangroves of Belize  

Microsoft Academic Search

Between the late 1980s and early 1990s, significant sections of the Belizean coast came under escalating pressure from development. The resulting habitat loss highlighted the need for a comprehensive assessment of the extent, characteristics and use of the country’s remaining mangrove.This paper reports on the resulting study, and confirms the presence of three true mangroves—Rhizophora mangle, Avicennia germinans and Laguncularia

M. R Murray; S. A Zisman; P. A Furley; D. M Munro; J Gibson; J Ratter; S Bridgewater; C. D Minty

2003-01-01

346

Radiocarbon dating and wood density chronologies of mangrove trees in arid Western Australia.  

PubMed

Mangrove trees tend to be larger and mangrove communities more diverse in tropical latitudes, particularly where there is high rainfall. Variation in the structure, growth and productivity of mangrove forests over climatic gradients suggests they are sensitive to variations in climate, but evidence of changes in the structure and growth of mangrove trees in response to climatic variation is scarce. Bomb-pulse radiocarbon dating provides accurate dates of recent wood formation and tree age of tropical and subtropical tree species. Here, we used radiocarbon techniques combined with X-ray densitometry to develop a wood density chronology for the mangrove Avicennia marina in the Exmouth Gulf, Western Australia (WA). We tested whether wood density chronologies of A. marina were sensitive to variation in the Pacific Decadal Oscillation Index, which reflects temperature fluctuations in the Pacific Ocean and is linked to the instrumental rainfall record in north WA. We also determined growth rates in mangrove trees from the Exmouth Gulf, WA. We found that seaward fringing A. marina trees (~10 cm diameter) were 48 ± 1 to 89 ± 23 years old (mean ± 1 ?) and that their growth rates ranged from 4.08 ± 2.36 to 5.30 ± 3.33 mm/yr (mean ± 1 ?). The wood density of our studied mangrove trees decreased with increases in the Pacific Decadal Oscillation Index. Future predicted drying of the region will likely lead to further reductions in wood density and their associated growth rates in mangrove forests in the region. PMID:24265797

Santini, Nadia S; Hua, Quan; Schmitz, Nele; Lovelock, Catherine E

2013-01-01

347

Kelp forest monitoring 1992 annual report. Channel Islands National Park. Final report  

Microsoft Academic Search

The 1992 results of the Channel Islands Natioanl Park Kelp Forest Monitoring Project are described in this report. Population dynamics of 68 taxa or categories of algae, fish, and invertebrates were measured at 16 permanent sites around the five islands within the park. Survey techniques utilized SCUBA and surface-supplied-air, and included quadrats, band transects, random point contacts, fish and video

D. Richards; D. Kushner

1992-01-01

348

Kelp forest monitoring 1994 annual report. Channel Islands National Park. Final report  

Microsoft Academic Search

The 1994 results of the Channel Islands Natonal Park Kelp Forest Monitoring Project are described in this report. Population dynamics of 68 taxa or categories of algae, fish, and invertebrates were measured at 16 permanent sites around the five islands within the park. Survey techniques utilized SCUBA and surface-supplied-air, and included quadrants, band transects, random point contacts, fish transects, video

D. Kushner; D. Lerma; D. Richards

1994-01-01

349

Kelp forest monitoring 1993 annual report. Channel Islands National Park. Final report  

Microsoft Academic Search

The 1993 results of the Channel Islands National Park Kelp Forest Monitoring Project are described in this report. Population dynamics of 68 taxa or categories of algea, fish, and invertebrates were measured at 16 permanent sites around the five islands within the park. Survey techniques utilized SCUBA and surface-supplied-air, and included quadrats, band transects, random contacts, fish transects, video transects,

D. Kushner; R. Walder; L. Gorodezky; D. Lerma; D. Richards

1993-01-01

350

Monitoring Small Mammal Populations in Coniferous Forest Ecosystems of Olympic National Park: Preliminary Assessment.  

National Technical Information Service (NTIS)

We conducted a 3-year pilot study to evaluate the feasibility of estimating and monitoring populations of small mammals in low-elevation old-growth coniferous forests of Olympic National Park. Primary objectives of the study were to: (1) determine species...

D. E. Seaman K. J. Jenkins S. L. Roberts

2005-01-01

351

Satellite monitoring for carbon monoxide and particulate matter during forest fire episodes in Northern Thailand.  

PubMed

This study explored the use of satellite data to monitor carbon monoxide (CO) and particulate matter (PM) in Northern Thailand during the dry season when forest fires are known to be an important cause of air pollution. Satellite data, including Measurement of Pollution in the Troposphere (MOPITT) CO, Moderate Resolution Imaging Spectroradiometer aerosol optical depth (MODIS AOD), and MODIS fire hotspots, were analyzed with air pollution data measured at nine automatic air quality monitoring stations in the study area for February-April months of 2008-2010. The correlation analysis showed that daily CO and PM with size below 10 ?m (PM10) were associated with the forest fire hotspot counts, especially in the rural areas with the maximum correlation coefficient (R) of 0.59 for CO and 0.65 for PM10. The correlations between MODIS AOD and PM10, between MOPITT CO and CO, and between MODIS AOD and MOPITT CO were also analyzed, confirming the association between these variables. Two forest fire episodes were selected, and the dispersion of pollution plumes was studied using the MOPITT CO total column and MODIS AOD data, together with the surface wind vectors. The results showed consistency between the plume dispersion, locations of dense hotspots, ground monitoring data, and prevalent winds. The satellite data were shown to be useful in monitoring the regional transport of forest fire plumes. PMID:24326733

Sukitpaneenit, Manlika; Kim Oanh, Nguyen Thi

2014-04-01

352

The roles of nearest neighbor methods in imputing missing data in forest inventory and monitoring databases  

Microsoft Academic Search

Almost universally, forest inventory and monitoring databases are incomplete, ranging from missing data for only a few records and a few variables, common for small land areas, to missing data for many observations and many variables, common for large land areas. For a wide variety of applications, nearest neighbor (NN) imputation methods have been developed to fill in observations of

BIANCA N. I. ESKELSON; Hailemariam Temesgen; Valerie Lemay; TARA M. BARRETT; NICHOLAS L. CROOKSTON; ANDREW T. HUDAK

2009-01-01

353

Food preferences of mangrove crabs related to leaf nitrogen compounds in the Segara Anakan Lagoon, Java, Indonesia  

Microsoft Academic Search

The large amounts of leaf litter produced by tropical mangrove forests serve as a major food source for the benthic fauna. The reasons for the preferential consumption of mangrove leaves by crabs are unclear as yet. We investigated the diet, food preferences and consumption rates of 8 dominant grapsoid crab species (Perisesarma spp., Episesarma spp., Metopograpsus latifrons, and Metaplax elegans)

Inga Nordhaus; Tabea Salewski; Tim C. Jennerjahn

2011-01-01

354

Effects of urban wastewater on crab and mollusc assemblages in equatorial and subtropical mangroves of East Africa  

Microsoft Academic Search

Mangrove forests are known to accomplish crucial ecosystem functions and services. They are nursery areas for fish, prawns and crabs, which provide coastal communities with a variety of food, timber and chemicals, and protect coasts from catastrophic events, such as tsunamis. Recently, a novel ecological service has been proposed for mangrove systems, namely natural wastewater treatment wetlands. This hypothesis was

Stefano Cannicci; Fabrizio Bartolini; Farid Dahdouh-Guebas; Sara Fratini; Carlos Litulo; Adriano Macia; Elisha J. Mrabu; Gil Penha-Lopes; José Paula

2009-01-01

355

Managing mangroves with benthic biodiversity in mind: Moving beyond roving banditry  

NASA Astrophysics Data System (ADS)

This review addresses mangrove management activities in the broader context of the diversity of the mangrove benthos. Goals for mangrove ecosystem management include silviculture, aquaculture, or 'ecosystem services' such as coastal protection. Silvicultural management of mangroves generally neglects the benthos, although benthic invertebrates may affect tree establishment and growth, and community composition of benthic invertebrates may be a reliable indicator of the state of managed mangrove forests. Similarly, mangrove aquaculture focuses on particular species with little attention paid either to impacts on other trophic levels or to feedbacks with the trees. Exploitation of mangrove-associated prawns, crabs, and molluscs has a total economic value > US $4 billion per year. These aquaculture operations still rely on wild-collected stock; world-wide patterns of exploitation fit the well-known process of 'roving banditry', where mobile agents move from location to location, rapidly exploiting and depleting local resources before moving on to other, as-yet unprotected grounds. Collection of brood stock and fishing for other external inputs required by aquaculture (e.g., 'trash fish') removes intermediate trophic levels from marine food webs, may destabilize them, and lead to secondary extinctions of higher-order predators. Increased attention being paid to the role of mangroves in coastal protection following the 2004 Indian Ocean tsunami provides an opportunity to reassess the relative merits of management focused on short-term economic gains. Managing for ecosystem services may ultimately preserve benthic biodiversity in mangrove ecosystems.

Ellison, Aaron M.

2008-02-01

356

Cross-shore gradients of physical disturbance in mangroves: implications for seedling establishment  

NASA Astrophysics Data System (ADS)

Mangroves may grow in an active sedimentary environment and are therefore closely linked to physical coastal processes. Seedlings colonize dynamic tidal flats, after which mangroves have the potential to change their physical environment by attenuating hydrodynamic energy and trapping sediments. Disturbance from hydrodynamic energy of waves or currents and the resulting sediment dynamics appear to be a critical bottleneck for seedling establishment on tidal flats and at the forest fringe. However, knowledge about the mechanisms at the single plant level and the spatial pattern of disturbance is limited. By means of a flume study, we demonstrate that a surface erosion threshold of as little as 1-3 cm depth can lead to failure of young seedlings. By monitoring accretion/erosion for 8 months along cross-shore transects in southwest Thailand, we show that, especially on the bare mudflat, the physical sediment disturbance regularly exceeds the critical erosion thresholds derived from the flume study. Physical sediment parameters along the same transects were analysed to deduct patterns of hydrodynamic energy attenuation. Grain size analysis and erosion/accretion data showed only limited energy dissipation within the fringing Avicennia/Sonneratia zone; sediment dynamics only dropped below lethal values for seedlings within the denser Rhizophora zone. Overall, present results emphasize that (i) seedling survival is extremely sensitive to physically driven sediment dynamics and (ii) that such physical disturbances are not only present on the tidal flats but can penetrate a significant distance into the forest. Spatio-temporal patterns in sediment dynamics should hence be considered when conducting restoration of mangrove ecosystems.

Balke, T.; Bouma, T. J.; Herman, P. M. J.; Horstman, E. M.; Sudtongkong, C.; Webb, E. L.

2013-08-01

357

Cross-shore gradients of physical disturbance in mangroves: implications for seedling establishment  

NASA Astrophysics Data System (ADS)

Mangroves grow in an active sedimentary environment and are therefore closely linked to physical coastal processes. Seedlings colonize dynamic tidal flats, after which mangroves have the potential to change their physical environment by attenuating hydrodynamic energy and trapping sediments. Disturbance from hydrodynamic energy of waves or currents and the resulting sediment dynamics appear to be a critical bottleneck for seedling establishment on tidal flats and at the forest fringe. However, knowledge about the mechanisms at the single plant level and the spatial pattern of disturbance is limited. By means of a flume study, we demonstrate that a surface erosion threshold of as little as 1-3 cm depth can lead to failure of young seedlings. By monitoring accretion/erosion for 8 months along cross-shore transects in southwest Thailand, we show that especially on the bare mudflat, the physical sediment disturbance regularly exceed the critical erosion thresholds derived from the flume study. Physical sediment parameters along the same transects were analysed to deduct patterns of hydrodynamic energy attenuation. Grain size analysis and erosion/accretion data showed only limited energy dissipation within the fringing Avicennia/Sonneratia zone, sediment dynamics only dropped below for seedlings lethal values within the denser Rhizophora zone. Overall, present results emphasize that (i) seedling survival is extremely sensitive to physical-driven sediment dynamics and (ii) that such physical disturbances are not only present on the idal flats but can penetrate a significant distance into the forest. Spatio-temporal patterns in sediment dynamics should hence be considered when conducting restoration of mangrove ecosystems.

Balke, T.; Bouma, T. J.; Herman, P. M. J.; Horstman, E. M.; Sudtongkong, C.; Webb, E. L.

2013-03-01

358

Painting the world REDD: addressing scientific barriers to monitoring emissions from tropical forests  

NASA Astrophysics Data System (ADS)

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 project scale to program readiness is a big step for all involved, and many are finding that it is not easy. Current barriers to national monitoring of forest carbon stocks and emissions range from technical to scientific, and from institutional to operational. In fact, a recent analysis suggested that about 3% of tropical countries currently have the capacity to monitor and report on changes in forest cover and carbon stocks (Herold 2009). But until now, the scientific and policy-development communities have had little quantitative information on exactly which aspects of national-scale monitoring are most uncertain, and how that uncertainty will affect REDD+ performance reporting. A new and remarkable study by Pelletier, Ramankutty and Potvin (2011) uses an integrated, spatially-explicit modeling technique to explore and quantify sources of uncertainty in carbon emissions mapping throughout the Republic of Panama. Their findings are sobering: deforestation rates would need to be reduced by a full 50% in Panama in order to be detectable above the statistical uncertainty caused by several current major monitoring problems. The number one uncertainty, accounting for a sum total of about 77% of the error, rests in the spatial variation of aboveground carbon stocks in primary forests, secondary forests and on fallow land. The poor quality of and insufficient time interval between land-cover maps account for the remainder of the overall uncertainty. These findings are a show-stopper for REDD+ under prevailing science and technology conditions. The Pelletier et al study highlights the pressing need to improve the accuracy of forest carbon and land cover mapping assessments in order for REDD+ to become viable, but how can the uncertainties be overcome? First, with REDD+ nations required to report their emissions, and with verification organizations wanting to check on the reported numbers, there is a clear need for shared measurement and monitoring approaches. One of the major stumbling blocks actually starts with the scientific community, which needs not only to develop h

Asner, Gregory P.

2011-06-01

359

Potential for Expanding the Near Real Time ForWarn Regional Forest Monitoring System to Include Alaska  

NASA Technical Reports Server (NTRS)

The on-line near real time (NRT) ForWarn system is currently deployed to monitor regional forest disturbances within the conterminous United States (CONUS), using daily MODIS Aqua and Terra NDVI data to derive monitoring products. The Healthy Forest Restoration Act of 2003 mandated such a system. Work on ForWarn began in 2006 with development and validation of retrospective MODIS NDVI-based forest monitoring products. Subsequently, NRT forest disturbance monitoring products were demonstrated, leading to the actual system deployment in 2010. ForWarn provides new CONUS forest disturbance monitoring products every 8 days, using USGS eMODIS data for current NDVI. ForWarn currently does not cover Alaska, which includes extensive forest lands at risk to multiple biotic and abiotic threats. This poster discusses a case study using Alaska eMODIS Terra data to derive ForWarn like forest change products during the 2010 growing season. The eMODIS system provides current MODIS Terra NDVI products for Alaska. Resulting forest change products were assessed with ground, aerial, and Landsat reference data. When cloud and snow free, these preliminary products appeared to capture regional forest disturbances from insect defoliation and fires; however, more work is needed to mitigate cloud and snow contamination, including integration of eMODIS Aqua data.

Spruce, Joseph P.; Gasser, Gerald; Hargrove, William; Smoot, James; Kuper, Philip D.

2014-01-01

360

Spectral multichannel monitoring of radiation within a mature mixed forest.  

PubMed

A multi-sensor system is described based on fiber optic technology and a diode array spectrometer for near-simultaneous measurement of spectral photon fluence rates (PFR) in the range of 360 nm to 1020 nm with a resolution of 0.8 nm, within a mature Norway spruce ( Picea abies [L.] Karst.) - European beech ( Fagus sylvatica L.) stand. 126 space-integrating spherical sensors, deployed in a regular grid above and within the canopy and on the forest floor, are sequentially connected to the spectrometer by means of fiber optics. About 1 s per sensor is needed to collect spectral data, store them on hard disk and move the channel multiplexer to the next fiber optic position. Data thus obtained serve to determine vertical profiles of wavelength-dependent photon extinction, especially for spectral ratios and wavebands, characterization of phenological stages, analyses of time series, and meteorological influences such as solar altitude and cloud cover. First measurements during leaf fall 2004 show a non-linear relation of the red/far-red ratio (R/FR) with relative photosynthetic PFR (PPFR (rel)). An analysis of relative PFR (PFR (rel)) quantifies the frequency of penumbral sunfleck occurrence and the fraction of incoming radiation on the forest floor. In-canopy measurements of daily means of PPFR (rel) and R/FR indicate that leaf unfolding and leaf fall can be described by a single sensor, independent of its vertical location within the canopy. PMID:16388465

Leuchner, M; Fabian, P; Werner, H

2005-11-01

361

The loss of species: mangrove extinction risk and geographic areas of global concern.  

PubMed

Mangrove species are uniquely adapted to tropical and subtropical coasts, and although relatively low in number of species, mangrove forests provide at least US $1.6 billion each year in ecosystem services and support coastal livelihoods worldwide. Globally, mangrove areas are declining rapidly as they are cleared for coastal development and aquaculture and logged for timber and fuel production. Little is known about the effects of mangrove area loss on individual mangrove species and local or regional populations. To address this gap, species-specific information on global distribution, population status, life history traits, and major threats were compiled for each of the 70 known species of mangroves. Each species' probability of extinction was assessed under the Categories and Criteria of the IUCN Red List of Threatened Species. Eleven of the 70 mangrove species (16%) are at elevated threat of extinction. Particular areas of geographical concern include the Atlantic and Pacific coasts of Central America, where as many as 40% of mangroves species present are threatened with extinction. Across the globe, mangrove species found primarily in the high intertidal and upstream estuarine zones, which often have specific freshwater requirements and patchy distributions, are the most threatened because they are often the first cleared for development of aquaculture and agriculture. The loss of mangrove species will have devastating economic and environmental consequences for coastal communities, especially in those areas with low mangrove diversity and high mangrove area or species loss. Several species at high risk of extinction may disappear well before the next decade if existing protective measures are not enforced. PMID:20386710

Polidoro, Beth A; Carpenter, Kent E; Collins, Lorna; Duke, Norman C; Ellison, Aaron M; Ellison, Joanna C; Farnsworth, Elizabeth J; Fernando, Edwino S; Kathiresan, Kandasamy; Koedam, Nico E; Livingstone, Suzanne R; Miyagi, Toyohiko; Moore, Gregg E; Ngoc Nam, Vien; Ong, Jin Eong; Primavera, Jurgenne H; Salmo, Severino G; Sanciangco, Jonnell C; Sukardjo, Sukristijono; Wang, Yamin; Yong, Jean Wan Hong

2010-01-01

362

Caribbean mangroves adjust to rising sea level through biotic controls on change in soil elevation  

USGS Publications Warehouse

Aim The long-term stability of coastal ecosystems such as mangroves and salt marshes depends upon the maintenance of soil elevations within the intertidal habitat as sea level changes. We examined the rates and processes of peat formation by mangroves of the Caribbean Region to better understand biological controls on habitat stability. Location Mangrove-dominated islands on the Caribbean coasts of Belize, Honduras and Panama were selected as study sites. Methods Biological processes controlling mangrove peat formation were manipulated (in Belize) by the addition of nutrients (nitrogen or phosphorus) to Rhizophora mangle (red mangrove), and the effects on the dynamics of soil elevation were determined over a 3-year period using rod surface elevation tables (RSET) and marker horizons. Peat composition and geological accretion rates were determined at all sites using radiocarbon-dated cores. Results The addition of nutrients to mangroves caused significant changes in rates of mangrove root accumulation, which influenced both the rate and direction of change in elevation. Areas with low root input lost elevation and those with high rates gained elevation. These findings were consistent with peat analyses at multiple Caribbean sites showing that deposits (up to 10 m in depth) were composed primarily of mangrove root matter. Comparison of radiocarbon-dated cores at the study sites with a sea-level curve for the western Atlantic indicated a tight coupling between peat building in Caribbean mangroves and sea-level rise over the Holocene. Main conclusions Mangroves common to the Caribbean region have adjusted to changing sea level mainly through subsurface accumulation of refractory mangrove roots. Without root and other organic inputs, submergence of these tidal forests is inevitable due to peat decomposition, physical compaction and eustatic sea-level rise. These findings have relevance for predicting the effects of sea-level rise and biophysical processes on tropical mangrove ecosystems.

McKee, K.L.; Cahoon, D.R.; Feller, I.C.

2007-01-01

363

The Loss of Species: Mangrove Extinction Risk and Geographic Areas of Global Concern  

PubMed Central

Mangrove species are uniquely adapted to tropical and subtropical coasts, and although relatively low in number of species, mangrove forests provide at least US $1.6 billion each year in ecosystem services and support coastal livelihoods worldwide. Globally, mangrove areas are declining rapidly as they are cleared for coastal development and aquaculture and logged for timber and fuel production. Little is known about the effects of mangrove area loss on individual mangrove species and local or regional populations. To address this gap, species-specific information on global distribution, population status, life history traits, and major threats were compiled for each of the 70 known species of mangroves. Each species' probability of extinction was assessed under the Categories and Criteria of the IUCN Red List of Threatened Species. Eleven of the 70 mangrove species (16%) are at elevated threat of extinction. Particular areas of geographical concern include the Atlantic and Pacific coasts of Central America, where as many as 40% of mangroves species present are threatened with extinction. Across the globe, mangrove species found primarily in the high intertidal and upstream estuarine zones, which often have specific freshwater requirements and patchy distributions, are the most threatened because they are often the first cleared for development of aquaculture and agriculture. The loss of mangrove species will have devastating economic and environmental consequences for coastal communities, especially in those areas with low mangrove diversity and high mangrove area or species loss. Several species at high risk of extinction may disappear well before the next decade if existing protective measures are not enforced.

Polidoro, Beth A.; Carpenter, Kent E.; Collins, Lorna; Duke, Norman C.; Ellison, Aaron M.; Ellison, Joanna C.; Farnsworth, Elizabeth J.; Fernando, Edwino S.; Kathiresan, Kandasamy; Koedam, Nico E.; Livingstone, Suzanne R.; Miyagi, Toyohiko; Moore, Gregg E.; Ngoc Nam, Vien; Ong, Jin Eong; Primavera, Jurgenne H.; Salmo, Severino G.; Sanciangco, Jonnell C.; Sukardjo, Sukristijono; Wang, Yamin; Yong, Jean Wan Hong

2010-01-01

364

Mangroves - what are they worth  

SciTech Connect

This paper is based on a study for FAO and on the management and utilization of mangroves in Asia and the Pacific. Land use options are examined in relation to the different roles which mangroves play (provision of firewood, charcoal, timber and pulp; wildlife; fisheries and aquaculture; and agriculture). Special attention is paid to mangrove management in Malaysia. (Refs 26)

Christensen, B.

1983-01-01

365

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

Microsoft Academic Search

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

Simon Joscha Geist; Inga Nordhaus; Saskia Hinrichs

366

Monitoring forest changes in the southwestern United States using multitemporal Landsat data  

USGS Publications Warehouse

Landsat time series data sets were acquired for the Santa Fe National Forest in New Mexico. This area includes the San Pedro Parks Wilderness area, which was designated as an official wilderness in 1964. Eight autumnal Landsat Thematic Mapper (TM) scenes acquired from 1988 to 2006 were analyzed to determine whether significant changes have occurred throughout the region during the past 18??years and, if so, to assess whether the changes are long-term and gradual or short-term and abrupt. It was found that, starting in about 1995, many of the conifer stands within the Wilderness area showed consistently gradual and marked increases in the Shortwave Infrared/Near Infrared Index. These trends generally imply decreases in canopy greenness or increases in mortality. Other high-elevation conifer forests located outside of the Wilderness area showed similar spectral trends, indicating that changes are potentially widespread. The spatial patterns of forest damage as inferred from the image analyses were very similar to the general patterns of insect defoliation damage mapped via aerial sketch mapping by the United States Department of Agriculture Forest Service Forest Health Monitoring Program. A field visit indicated that zones of spectral change are associated with high levels of forest damage and mortality, likely caused by a combination of insects and drought. The study demonstrates the effectiveness of using historical Landsat data for providing objective and consistent long-term assessments of the gradual ecosystem changes that are occurring within the western United States.

Vogelmann, J. E.; Tolk, B.; Zhu, Z.

2009-01-01

367

An Early Warning System for Identification and Monitoring of Disturbances to Forest Ecosystems  

NASA Astrophysics Data System (ADS)

Forest ecosystems are susceptible to damage due to threat events like wildfires, insect and disease attacks, extreme weather events, land use change, and long-term climate change. Early identification of such events is desired to devise and implement a protective response. The mission of the USDA Forest Service is to sustain the health, diversity, and productivity of the nation's forests. However, limited resources for aerial surveys and ground-based inspections are insufficient for monitoring the large areas covered by the U.S. forests. The USDA Forest Service, Oak Ridge National Laboratory, and NASA Stennis Space Center are developing an early warning system for the continuous tracking and long-term monitoring of disturbances and responses in forest ecosystems using high resolution satellite remote sensing data. Geospatiotemporal data mining techniques were developed and applied to normalized difference vegetation index (NDVI) products derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) MOD 13 data at 250 m resolution on eight day intervals. Representative phenologically similar regions, or phenoregions, were developed for the conterminous United States (CONUS) by applying a k-means clustering algorithm to the NDVI data spanning the full eight years of the MODIS record. Annual changes in the phenoregions were quantitatively analyzed to identify the significant changes in phenological behavior. This methodology was successfully applied for identification of various forest disturbance events, including wildfire, tree mortality due to Mountain Pine Beetle, and other insect infestation and diseases, as well as extreme events like storms and hurricanes in the United States. Where possible, the results were validated and quantitatively compared with aerial and ground-based survey data available from different agencies. This system was able to identify most of the disturbances reported by aerial and ground-based surveys, and it also identified affected areas that were not covered by any of the surveys. Analysis results and validation data will be presented.

Marshall, A. A.; Hoffman, F. M.; Kumar, J.; Hargrove, W. W.; Spruce, J.; Mills, R. T.

2011-12-01

368

Monitoring changes in riverine forests of Sindh-Pakistan using remote sensing and GIS techniques  

NASA Astrophysics Data System (ADS)

Depletion in the forest area threatens the sustainability of agricultural production systems and en-dangers the economy of the country. Every year extensive areas of arable agricultural and forestlands are degraded and turned into wastelands over time, due to natural causes or human interventions. Depletion in forest cover, therefore, has an important impact on socio-economic development and ecological balance. High population growth rate in Pakistan is one of the main causes for rapid deterioration of the physical environment and natural resource base. In view of this, it was felt necessary to carryout landuse studies focusing on mapping the past and present conditions and the extent of forests and rangelands using satellite remote sensing (SRS) and Geographic Information System (GIS) technologies. The SRS and GIS technologies provide a possible means of monitoring and mapping the changes occurring in natural resources and the environment on a continuous basis. The riverine forests of Sindh mostly growing along the river Indus in the flood plains are spread over an area of 241,000 ha but are disappearing very rapidly. Construction of dams/barrages on the upper reaches of the river Indus for hydroelectric power and irrigation works have significantly reduced the discharge of fresh water into the lower Indus basin and as a result 100,000 acres of forests have disappeared. Furthermore, heavy floods that occurred in 1978, 1988, 1992 and 1997, altered the course of the River Indus in many places, especially in the lower reaches, this has also damaged the riverine forests of Sindh. An integrated approach involving analysis of SRS data from 1977 to 1998 and GIS technique have been used to evaluate the geographic extent and distribution of the riverine forests of Sindh and to monitor temporal changes in the forest cover between 1977 and 1990; 1990 and 1998; and 1977 and 1998. The integrated landuse forest cover maps have shown not only the temporal changes that occur in the riverine forest but also in the river Indus course between 22 years period.

Siddiqui, M. N.; Jamil, Z.; Afsar, J.

369

Monitoring of environmental conditions in taiga forests using ERS-1 SAR  

SciTech Connect

Synthetic-aperture radar images of forest site near Manley Hot Springs (64[degree]N, 151[degree]W), Alaska, were collected between August 1991 and December 1991, day and night, every 3 days, at C-band frequency ([lambda] = 5.7 cm), vertical receive and transmit polarization, by the European Space Agency First Remote Sensing Satellite, ERS-1. During the same period, air and soil temperatures and dielectric and gravimetric moisture properties of the forest canopy and forest floor were monitored in three forest stands dominated, respectively, by black spruce (Picea mariana), white spruce (Picea glauca), and balsam poplar (Populus balsamifera). The calibrated ERS-1 radar backscatter values, [sigma][degree], of the forest stands are shown to exhibit a pronounced temporal pattern, with little separability between tree species. The largest change in [sigma][degree], a 3-dB decrease almost independent of tree species, is observed in early winter when the soil and vegetation freeze. In the summer, temporal fluctuations in [sigma][degree] are about 1--2 dB in magnitude, depending on tree species. Diurnal variations in [sigma][degree] are as large as 2 dB during fall freeze-up, and less than 1 dB in summer and winter. These temporal variations in radar backscatter from the forest are interpreted using the MIMICS radar backscatter model and the in situ surface observations as due to changes in the dielectric properties of the forest floor and forest canopy induced by precipitation (summer), drought (fall), and freezing (fall-winter) events. In winter, [sigma][degree] increases across the entire landscape, probably because of volume scattering from large depth hoar ice crystals forming in the snow pack.

Rignot, E.; Way, J.B.; McDonald, K. (Jet Propulsion Lab., Pasadena, CA (United States)); Viereck, L.; Williams, C.; Adams, P.; Payne, C.; Wood, W. (Inst. of Northern Forestry, Fairbanks, AK (United States)); Shi, J. (Univ. of California, Santa Barbara, CA (United States))

1994-08-01

370

Fate and effects of anthropogenic chemicals in mangrove ecosystems: a review.  

PubMed

The scientific literature for fate and effects of non-nutrient contaminant concentrations is skewed for reports describing sediment contamination and bioaccumulation for trace metals. Concentrations for at least 22 trace metals have been reported in mangrove sediments. Some concentrations exceed sediment quality guidelines suggesting adverse effects. Bioaccumulation results are available for at least 11 trace metals, 12 mangrove tissues, 33 mangrove species and 53 species of mangrove-habitat biota. Results are specific to species, tissues, life stage, and season and accumulated concentrations and bioconcentration factors are usually low. Toxicity tests have been conducted with 12 mangrove species and 8 species of mangrove-related fauna. As many as 39 effect parameters, most sublethal, have been monitored during the usual 3 to 6 month test durations. Generalizations and extrapolations for toxicity between species and chemicals are restricted by data scarcity and lack of experimental consistency. This hinders chemical risk assessments and validation of effects-based criteria. PMID:21601968

Lewis, Michael; Pryor, Rachel; Wilking, Lynn

2011-10-01

371

Use of multiple chemical tracers to define habitat use of Indo-Pacific mangrove crab, Scylla serrata (Decapoda: Portunidae)  

USGS Publications Warehouse

The mangrove or mud crab, Scylla serrata, is an important component of mangrove fisheries throughout the Indo-Pacific. Understanding crab diets and habitat use should assist in managing these fisheries and could provide additional justification for conservation of the mangrove ecosystem itself. We used multiple chemical tracers to test whether crab movements were restricted to local mangrove forests, or extended to include adjacent seagrass beds and reef flats. We sampled three mangrove forests on the island of Kosrae in the Federated States of Micronesia at Lelu Harbor, Okat River, and Utwe tidal channel. Samples of S. serrata and likely food sources were analyzed for stable carbon (??13C), nitrogen (??15N), and sulfur (??34S) isotopes. Scylla serrata tissues also were analyzed for phosphorus (P), cations (K, Ca, Mg, Na), and trace elements (Mn, Fe, Cu, Zn, and B). Discriminant analysis indicated that at least 87% of the crabs remain in each site as distinct populations. Crab stable isotope values indicated potential differences in habitat use within estuaries. Values for ??13C and ??34S in crabs from Okat and Utwe were low and similar to values expected from animals feeding within mangrove forests, e.g., feeding on infauna that had average ??13C values near -26.5???. In contrast, crabs from Lelu had higher ?? 13C and ??34S values, with average values of -21.8 and 7.8???, respectively. These higher isotope values are consistent with increased crab foraging on reef flats and seagrasses. Given that S. serrata have been observed feeding on adjacent reef and seagrass environments on Kosrae, it is likely that they move in and out of the mangroves for feeding. Isotope mixing model results support these conclusions, with the greatest mangrove ecosystem contribution to S. serrata diet occurring in the largest mangrove forests. Conserving larger island mangrove forests (> 1 km deep) appears to support crab foraging activities. ?? 2007 Coastal and Estuarine Research Federation.

Demopoulos, A. W. J.; Cormier, N.; Ewel, K. C.; Fry, B.

2008-01-01

372

Biomass and Carbon Sequestration in Community Mangrove Plantations and a Natural Regeneration Stand in the Ayeyarwady Delta, Myanmar  

NASA Astrophysics Data System (ADS)

Mangroves in the Ayeyarwady Delta is one of the most threatened ecosystems, and is rapidly disappearing as in many tropical countries. The deforestation and degradation of mangrove forest in the Ayeryarwady Delta results in the shortage of wood resources and declining of environmental services that have been provided by the mangrove ecosystem. Cyclone Nargis struck the Ayeyarwady Delta on 2 May 2008 with an intensity unprecedented in the history of Myanmar. The overexploitation of mangroves because of local demands for fuel wood and charcoal and the conversion of mangrove forest land into agricultural land or shrimp farms over the past decades have increased the loss of human life and the damage to settlements caused by the Cyclone.The biomass study was conducted in September of 2006 in Bogale Township in the Ayeyarwady Delta and continued monitoring in September of each year from 2007 to 2010. Above and below ground biomass was studied in six years old mangrove plantations of Avicenia marina (Am), Avicenia officinalis (Ao) and Sonneratia apetala (Sa) and a naturally regenerated stand under regeneration improving felling operation (NR: consists of Ceriops decandra, Bruguiera sexangula, and Aegicerus corniculatum) protected for seven years since 2000. These stands were established by small-scale Community Forestry scheme on abandoned paddy fields where natural mangroves once existed. Common allometric equations were developed for biomass estimation by performing regressions between dry weights of trees as dependent variables and biometric parameters such as stem diameter, height and wood density as independent variables. The above and below ground biomass in NR stand (70 Mg ha-1 and 104 Mg ha-1) was the greatest (P < 0.001), and followed by Sa plantation (69 Mg ha-1 and 32 Mg ha-1), Am plantation (25 Mg ha-1 and 27 Mg ha-1) and Ao plantation (21 Mg ha-1 and 26 Mg ha-1). The total carbon stock in biomass was 73 Mg C ha-1 in NR stand, 43 Mg C ha-1 in Sa plantation, 21 Mg C ha-1 in Am plantation and 18 Mg C ha-1 in Ao plantation respectively. The averaged total soil carbon stock up to 1 m soil depth in plantation site was estimated to be 167 ± 58 Mg C ha-1 which was nearly two times higher than that of current paddy fields 85 ± 17 Mg C ha-1. These facts suggest the feasibility of the mangrove plantation and induced natural regeneration as a carbon sequestration tool. The establishment of mangrove plantations appeared to be one measure for reducing the risk of cyclone damage after the Cyclone Nargis. This may reduce future human loss by cyclones and also improve the life of local people by increasing timber resources and environmental services.

Thant, Y. M.; Kanzaki, M.; nil

2011-12-01

373

Monitoring and Research Strategy for Forests-Environmental Monitoring and Assessment Program.  

National Technical Information Service (NTIS)

To protect, manage, and use forest resources effectively, the condition of these resources must be known. Concern about documented and potential effects of air pollutants in combination with other multiple, interacting stresses has been a major impetus be...

C. J. Palmer K. H. Ritters T. Strickland D. L. Cassell G. E. Byers

1992-01-01

374

RIMBAMON©: A forest monitoring system using wireless sensor networks  

Microsoft Academic Search

Wireless sensor networks (WSNs) have emerged as one of the most promising research areas in recent years and are widely recognized as powerful means for in situ observations of events and environments over long period of time. The wide spectrum of applications WSNs can offer such as environment and habitat monitoring, healthcare applications, home or industrial automation and control, product

Azlan Awang; Muhamad Haidar Suhaimi

2007-01-01

375

Modeling Biological Invasion: The Case Of Dengue And Mangrove  

NASA Astrophysics Data System (ADS)

It is well known that organism invades territory in the form of wave fronts whose characteristics are determined primarily by environmental conditions such as hydrology, salinity, climate, carrying capacity and resource. In this invited paper, we will consider two ecosystems, one comprising mosquitoes of the species Aedes aegypti that are the vector of dengue fever while the second consists of coastal ecosystem composed of mixtures of mangrove and hardwood hammocks in south Florida. Their dispersal dynamics modeled by simulations DEER and MANHAM will be discussed. Implications regarding approaches for the eradication of A. aegypti and the replanting or recovery of coastal mangrove forests will be presented.

Lye, Koh Hock; Yean, Teh Su; Ismail, Ahmad Izani Md.; Deangelis, Donald L.

2008-01-01

376

Traditional and medicinal uses of mangroves  

Microsoft Academic Search

This review examines the recent investigations on the biological activities of extracts and chemicals identified from mangroves (mangroves, mangrove minors and mangal associates). It describes how people have and are using mangroves on a traditional basis. It also describes the world's mangrove resources and products, in terms of their economical importance, medicinal values and other uses and functions. The economical

W. M. Bandaranayake; Townsville MC

1998-01-01

377

The effect of a protected area on the tradeoffs between short-run and long-run benefits from mangrove ecosystems  

PubMed Central

Protected areas are used to sustain biodiversity and ecosystem services. However, protected areas can create tradeoffs spatially and temporally among ecosystem services, which can affect the welfare of dependent local communities. This study examines the effect of a protected area on the tradeoff between two extractive ecosystem services from mangrove forests: cutting mangroves (fuelwood) and harvesting the shrimp and fish that thrive if mangroves are not cut. We demonstrate the effect in the context of Saadani National Park (SANAPA) in Tanzania, where enforcement of prohibition of mangrove harvesting was strengthened to preserve biodiversity. Remote sensing data of mangrove cover over time are integrated with georeferenced household survey data in an econometric framework to identify the causal effect of mangrove protection on income components directly linked to mangrove ecosystem services. Our findings suggest that many households experienced an immediate loss in the consumption of mangrove firewood, with the loss most prevalent in richer households. However, all wealth classes appear to benefit from long-term sustainability gains in shrimping and fishing that result from mangrove protection. On average, we find that a 10% increase in the mangrove cover within SANAPA boundaries in a 5-km2 radius of the subvillage increases shrimping income by approximately twofold. The creation of SANAPA shifted the future trajectory of the area from one in which mangroves were experiencing uncontrolled cutting to one in which mangrove conservation is providing gains in income for the local villages as a result of the preservation of nursery habitat and biodiversity.

McNally, Catherine G.; Uchida, Emi; Gold, Arthur J.

2011-01-01

378

Application of spectral invariants for monitoring forests across multiple scales  

NASA Astrophysics Data System (ADS)

The concept of canopy spectral invariants expresses the observation that simple algebraic combinations of leaf scattering and canopy reflectance spectra become wavelength independent and determine two variables -- the recollision probability and directional escape factor. They quantify two events: a photon scattered from a phytoelement will recollide or escape the canopy in a given direction, respectively. The spectral invariants specify an accurate relationship between spectral responses of vegetation to incident solar radiation from leaf to canopy scales and thus provide a framework through which structural information can be maintained in a self-consistent manner across multiple scales. The objectives of this research are to (1) explain the physics behind the correlation between multi-angle spectral data and canopy height; (2) develop a physically based approach for forest classification from hyperspectral data; (3) investigate the sensitivity of canopy reflectance to leaf nitrogen concentration. Analyses of Airborne Multi-angle Imaging SpectroRadiometer (AirMISR) and airborne Laser Vegetation Imaging Sensor (LVIS) data suggest a dominant role of the escape factor in the sensitivity of multi-angle spectral data to canopy height. Analyses of ground and Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data suggest that the total escape probability (one minus recollision probability) varies as a power function with the exponent related to the number of nested hierarchical levels present in satellite pixels. Its base is a geometrical mean of local total escape probabilities and accounts for the cumulative effect of canopy structure over a wide range of scales. The escape factor to the total escape probability ratio becomes independent of the number of hierarchical levels and is a function of tree crown and stand geometry. These properties allow for the natural separation of forest types based on the location of points on the total escape probability versus the ratio log- log plane. Analyses of ground data on leaf nitrogen, leaf and canopy structure as well as AVIRIS and LVIS data suggest that both Near InfraRed (NIR) canopy reflectance and canopy nitrogen are positively correlated with canopy structure. This finding suggests that structure is the dominant factor causing the observed positive correlation between canopy NIR reflectance and nitrogen concentration for data examined.

Schull, Mitchell A.

379

Carbon Sequestration Potential in Mangrove Wetlands of Southern of India  

NASA Astrophysics Data System (ADS)

Mangrove forest and the soil on which it grows are major sinks of atmospheric carbon. We present the results of a study on the carbon sequestration in the ground biomass of Avicennia marina including the organic carbon deposition, degradation and preservation in wetland sediments of Muthupet mangrove forest (southeast coast of India) in order to evaluate the influence of forests in the global carbon cycle. The inventory for estimating the ground biomass of Avicennia marina was carried out using random sampling technique (10 m × 10 m plot) with allometric regression equation. The carbon content in different vegetal parts (leaves, stem and root) of mangrove species and associated marshy vegetations was estimated using the combustion method. We observe that the organic carbon was higher (ca. 54.8%) recorded in the stems of Aegiceras corniculatum and Salicornia brachiata and lower (ca. 30.3%) in the Sesuvium portulacastrum leaves. The ground biomass and carbon sequestration of Avicennia marina are 58.56±12.65 t/ ha and 27.52±5.95 mg C/ha, respectively. The depth integrated organic carbon model profiles indicate an average accumulation rate of 149.75gC/m2.yr and an average remineralization rate of 32.89gC/m2.yr. We estimate an oxidation of ca. 21.85% of organic carbon and preservation of ca. 78.15% of organic carbon in the wetland sediments. Keywords: Above ground biomass, organic carbon, sequestration, mangrove, wetland sediments, Muthupet.

Chokkalingam, L.; Ponnambalam, K.; Ponnaiah, J. M.; Roy, P.; Sankar, S.

2012-12-01

380

Young Mangrove Stands Produce a Large and High Quality Litter Input to Aquatic Systems  

Microsoft Academic Search

Mangrove swamps are key ecosystems along the Vietnam coast. Although mangrove litter is thought to represent an important input of organic matter and nutrients to the coastal aquatic systems, the factors determining the quality and size of this litter flux have not been studied so far. We monitored leaf, stipule, twig, and reproductive litter monthly in monocultures of Rhizophora apiculata

B. T. Nga; H. Q. Tinh; D. T. Tam; M. Scheffer; R. M. M. Roijackers

2005-01-01

381

Operational multi-sensor design for forest carbon monitoring to support REDD+ in Kalimantan, Indonesia  

NASA Astrophysics Data System (ADS)

Parties to the United Nations Framework Convention on Climate Change (UNFCCC) have been requested to establish robust and transparent nati