Sustainable Management Of Mangrove Ecosystems Research Articles

Sustainable management model and ecosystem services of mangroves based on socio-ecological system on the coast of Batu Bara Regency, Indonesia

The coastal areas of Batu Bara Regency, Indonesia, face significant challenges due to the conversion of mangrove ecosystems into ponds and tourist destinations. This transformation not only results in the loss of natural coastal protection but also disrupts hydro-oceanography patterns, necessitating comprehensive management solutions that address ecological, economic, and social aspects. To this end, a research was carried out during June to August 2023 developing an integrated management model for sustainable preservation of mangrove ecosystems in Batu Bara Regency. The research aims to evaluate the economic benefits of mangrove ecosystems, particularly emphasizing on regulating, provisioning, and cultural services. The Analytic Network Process (ANP) method is employed to determine priority management strategies by considering the interrelationships between ecological, economic, social, and institutional factors. The model construction incorporates insights from literature reviews and expert interviews, facilitating the formulation of solutions for various aspects of mangrove ecosystem management. The economic value of mangrove ecosystems is estimated in three districts of Batu Bara Regency, with significant contributions to both provisioning and regulating services. In conclusion, the research underscores the importance of strategies such as mangrove area rehabilitation, ecotourism development, outreach and assistance, and community involvement in ensuring the sustainable management of mangrove ecosystems. These strategies hold the potential to preserve these valuable ecosystems, benefiting the environment and local communities alike.

Monitoring the light pollution changes of China’s mangrove forests from 1992-2020 using nighttime light data

Mangrove forests are one of the most biologically diverse and productive ecosystems on Earth. They are important breeding and nursing grounds for amphibians, invertebrates, birds, fish, etc. Light pollution may cause serious degradation of biodiversity in the ecosystem. A report of the long-term holistic views of light pollution changes is essential for sustainable management of mangrove ecosystems. However, to date, such studies have rarely been carried out. This study aimed to monitor the long-term light pollution changes of China’s mangrove forests. To achieve this goal, we used time-series nighttime light (NTL) data to build continuous light pollution data. NTL maps made with DMSP-OLS (DNL) or NPP-VIIRS (VNL) are widely utilized in research on human activity. However, DMSP and VIIRS images are different in spatial resolution, radiation resolution, and data saturation. Thus, this study innovatively set an optimal threshold for generating consistent light pollution data in mangrove areas from 1992-2020. The results showed that: (1) the proportion of light-polluted mangrove forests in China increased from 12% in 1992 to 52% in 2020; (2) the largest net increase occurred in Guangxi with an area of 4,086 ha, followed by Guangdong (3,365 ha) and Hainan (2,944 ha); (3) Zhejiang had the largest proportion of net growth (from 0% in 1992 to 99% in 2020), followed by Hainan (66%) and Fujian (59%). Mangrove forests have been protected and restored for decades in China; this study indicates that the establishment of nature reserves is effective in preventing the light pollution of mangroves and provides the first long-term multi-temporal dataset of light pollution in China’s mangrove forests. This comprehensive information could support related studies and facilitate the development of applicable coastal management strategies in China.

Economic Valuation of Mangroves and a Linear Mixed Model-Assisted Framework for Identifying Its Main Drivers: A Case Study in Benin

Mangroves are brackish wetland ecosystems found in tropical areas. They are highly productive ecosystems that contribute to the economic empowerment of local communities. Proper estimation of their monetary value and the extent of their contribution to rural households’ income, although challenging, is paramount for sustainable management decisions. This study aimed to estimate the total economic wealth earned from mangrove ecosystems in Benin. Specifically, the study assessed the diversity of ecosystem services (ESs) provided by mangroves and the contribution of ESs to the total annual economic value of mangroves, and it identified socio-demographic drivers of the total economic value at the individual informant level. In total, 298 informants from 15 villages were interviewed to determine the diversity of mangrove ESs. The ESs were then gathered per category. Household-level economic values of mangroves, economic values of mangroves per ES category, and total economic value were estimated by combining diverse approaches. The contribution of each category of ES to the total economic value (TEV) was determined. A Principal Component Analysis (PCA) was applied to describe the relationships between the economic value of categories of ESs. A Linear Mixed Effect Model (LMEM) was used to determine valid socio-demographic drivers of the TEV. Twenty-nine ESs were identified, with regulation and recreation services being the best contributors to annual TEV, which was estimated at USD 1.29 billion (USD 195,223.69/hectare). Stakeholdership followed by household size are the main socio-demographic drivers of TEV. The identified ESs and their estimated economic value can be incorporated into policy briefs and technical sheets to (i) promote ESs for the optimisation of TEV and (ii) raise awareness and funding for the conservation and sustainable management of mangrove ecosystems.

The fate of mangrove ecosystem sustainability on the shrimp cultivation area in Tulang Bawang District, Lampung, Indonesia

The exploitation of mangrove forests for economic purposes is rampant in tropical countries nowadays, particularly for shrimp farming, such as in the Lampung green belt in the front of the Java Sea. So, ensuring the sustainability of existing mangroves is the need of the hour. In view of above, this study aims to analyze the sustainability index of mangrove ecosystem management and the sustainability status of the mangrove ecosystem from the ecological, economic, social, and institutional dimensions using the Multidimensional Scaling (MDS) method through the Rapid Appraisal for Fisheries (RAPFISH) approach in East Rawajitu Sub-district, Tulang Bawang District, Lampung Province, Indonesia. The analysis revealed that mangrove ecosystem management’s sustainability index was categorized as ‘less sustainable’ (index 43.01 out of 100). Meanwhile, the social dimension (51.65) was categorized as ‘quite sustainable’, and other dimensions (ecological, economic, and institutional) were ‘less sustainable.’ Therefore, it is proposed that further development of the social dimension is a strategic way to develop the other three sustainability dimensions to achieve ecosystem sustainability as a whole in the study area. Alternative strategies that can be applied for sustainable management of mangrove ecosystems in East Rawajitu Sub-district, Tulang Bawang District are increasing coordination between stakeholders, creating formal regulations, increasing the productivity and creativity of Ikatan Istri-istri Petambak Dipasena (ISTANA), formulating an integrated mangrove ecosystem management plan program, undertaking rehabilitation efforts, increasing the role of mangrove groups, and increase the attention of researchers.

SOSIALISASI MANFAAT EKOSISTEM MANGROVE SEBAGAI UPAYA PENCEGAHAN ILLEGAL LOGGING DI DESA LATAWE KABUPATEN MUNA BARAT

Utilization of the mangrove ecosystem in West Muna Regency is widely used as firewood, building materials, and other infrastructure development. This utilization has an impact on reducing the area and density of the mangrove ecosystem, thereby reducing the functions and benefits of the mangrove ecosystem. Community participation is very necessary in the sustainable management of mangrove ecosystems. This can happen if the government and the community understand well about the functions and benefits of the mangrove ecosystem for people's lives. This community service activity is a form of independent service as an effort to apply knowledge to advance people's lives through sustainable mangrove ecosystem management. The socialization was carried out using a discussion method with the village government and key figures who played a role in policy making in Latawe Village, West Muna Regency. This service activity provides a deep understanding to the community regarding the introduction of mangrove species, the benefits and importance of conserving the mangrove ecosystem. This is indicated by the follow-up from the village government and community leaders to rehabilitate mangroves on critical lands by involving the full participation of the community. The acquisition of seeds for rehabilitation is carried out independently by the community with funding assistance from the Ministry of Marine Affairs and Fisheries through the Directorate General of Marine Spatial Management and Small Islands. Service activities will continue by continuing to provide direct and indirect assistance in rehabilitation activities starting from determining the location, selecting seeds, sowing seeds, and rehabilitation techniques

Analysis of SWOT Strategy in Sustainable Management of Mangrove Ecosystems in Kaliwlingi Village, Brebes Sub-district, Brebes District

This study aims to obtain a strategy for managing sustainable mangrove ecosystems in Kaliwlingi Village, Brebes Sub-district, Brebes District. This study uses qualitative research with phenomenological methods. The data needed in this research is primary data obtained directly from respondents and secondary data obtained from data sources that do not directly provide data. The analytical method used in this research is the analysis of Strengths, Weaknesses, Opportunities and Threats (SWOT), and Quantitative Strategic Planning Matrix (QSPM) to determine the right strategy in managing sustainable mangrove ecosystems. The results of the Internal Factor Evaluation (IFE) calculation have a score of 2.21, which is below the average score of 2.50, indicating a less strong internal position. The results of the External Factor Evaluation (EFE) calculation show that the total score of 2.03 is below the average score of 2.50, indicating a less strong external position. The integration stage of IFE and EFE uses a SWOT matrix. The results of the combined score between IFE and EFE are 2.21; 2.03 in the first quadrant position, which is a favorable situation. The results of the QSPM show the Total Attractiveness Score (TAS) of strategy I as much as 6,009 has the highest TAS value and is the chosen alternative priority strategy. The results of the study show that the expansion strategy that must be taken by the Brebes Regency Government is to provide opportunities for the community to manage the mangrove ecosystem independently with assistance from the Government of Brebes District.

Spartina alterniflora invasion and mangrove restoration alter diversity and composition of sediment diazotrophic community

Ecological restoration using native mangrove species (i.e., Kandelia obovata) is a practical approach for controlling Spartina alterniflora invasion in the coastal wetlands. Diazotrophs play a critical role in enhancing productivity of both S. alterniflora and mangrove plant, via providing new nitrogen to the coastal wetlands ecosystems. However, response of the diazotrophic community to S. alterniflora invasion and subsequent mangrove restoration remains unclear. The present study monitored sediment physicochemical properties and diazotrophic communities across a chronosequence of restored mangrove wetland (bare mudflat, invasive S. alterniflora stands, 3-year and 10-year K. obovata restoration areas, and mature K. obovata forests over 30 years). The results showed an orderly succession in the sediment properties and diazotrophic community composition after S. alterniflora invasion and along mangrove restoration chronosequences. Almost all sediment nutrient contents (e.g., TC, TN, and C/N) were significantly (P < 0.05) increased by S. alterniflora invasion, then they decreased sharply in the newly restored mangrove and increased gradually with restoration ages, with the highest values in the mature mangrove. The diazotrophs demonstrated distinct community structure in different seasons. Diazotrophic alpha diversity increased with S. alterniflora invasion and mangrove restoration age in winter. Sulfate-reducing bacteria (SRB) was the dominant diazotrophic group, especially Desulfuromonadales. Moreover, network analyses revealed that SRB groups were the major keystone taxa. The relative abundance of Desulfuromonadales decreased, while the abundance of Chromatiales increased gradually with the S. alterniflora invasion and mangrove restoration age. Redundancy analysis revealed that TC, TN, and TS were the significant (P < 0.05) environmental factors in altering sediment diazotrophic communities in both seasons. These findings expand the current understanding of succession patterns of diazotrophic communities in mangrove restoration and provide new perspectives on the sustainable management of mangrove ecosystems.

Mapping disturbance in mangrove ecosystems: Incorporating landscape metrics and PCA-based spatial analysis

Mangrove ecosystems are of high ecological value and occur in tropical and subtropical coastal areas. They consist of salt-tolerant woody plants and are highly complex and productive.Here, a novel approach was developed to map disturbances and evaluate the ecological status of Iranian mangroves based on multispectral WorldView-2 and Sentinel-2 and remote sensing techniques. A land cover map was generated that serves as basis to assess changes in the composition and structure of mangrove ecosystems. The spatial disturbance index (SDI) was calculated based on landscape metrics and principal component analysis (PCA) in order to detect mangroves degraded on Qeshm Island, Iran. The approach comprised: (I) selection of landscape metrics, (II) definition of the hexagon cell scale, (III) completion of a PCA of the standardized values ​​of eight selected metrics, and (IV) modeling of the SDI based on eigenvalues and a loading factor. For validation, the variance inflation factor (VIF) was used. The results indicate that the best set of key metrics to quantify SDI comprises the eight metrics patch density (PD), total edge (TE), mean patch size (MPS), mean shape index (MSI), Euclidean nearest neighbor distance (ENND), contagion (CONT), splitting index (SPLIT), and Shannon’s diversity index (SHDI). The first three components of the PCA explained in total 87% (47%, 27%, and 13%, respectively) of the variance of information distribution, demonstrating the effectiveness of the PCA. Then, based on the disturbance index, five spatial levels, ranging from very low to very high disturbances, were identified. This approach enabled to detect the zonation of disturbance that has occurred in the region and supports the sustainable management of mangrove ecosystems and future planning efforts, thus making their conservation more realistic.

ESTIMATION AND MAPPING OF ABOVE GROUND BIOMASS OF MANGROVE FOREST USING ALOS-2 PALSAR-2 IN BENOA BAY, BALI, INDONESIA

Mangrove forests are distributed in limited areas around along costlines, but they play important role in carbon fixation and carbon storafe in the tropic areas. Mangrove forests are a transitional ecosystem between land-based oceans, most of which are well-known along the tropic and subtropical coastlines. Mangrove ecosystems have an ecological function as an absorber and storage of carbon in the form of biomass. Remote sensing technology can include data spatially and temporally. This makes it easy to predict the overall extent and carbon stock. So that in the context of sustainable management of mangrove ecosystems it can be utilized to monitor mangrove carbon balance and become the basis for policy development. The objective of this study was to determine the potential above ground biomass model from ALOS-2 PALSAR-2 data in mangrove forests of Benoa Bay, Bali. In this research, the filter used is frost filtering. AGB model was constructesd by using dual-polarization L-band SAR of ALOS-2 PALSAR-2 data and field inventory plots. 40 plots were collected in the field and the allometric equation. The prediction model for aboveground biomass potential based on the ALOS-2 PALSAR-2 image on HV polarization in the mangrove Benoa Bay area, the correlation value (r) of 0.82, the coefficient of determination (R2) of 0.68. Validation model aboveground biomass-based, correlation value (r) of 0.90, the coefficient of determination (R2) of 0.82, and RMSE of ± 39.85. The potential of aboveground biomass and carbon stock in the mangrove Benoa Bay area is 364,241.87 Mg and 171,193.67 Mg C with the ability to absorb carbon dioxide (CO2) of 628,280.81 Mg CO2 Sequestration same with 3 bottles in 2020.Keywords: Mangrove; Aboveground biomass (AGB); HV Polarization; ALOS-2 PALSAR-2.

MIKOKO: A Data Sharing Platform On Kenyan Mangrove Species

The Mangrove ecosystem offers a range of benefits and opportunities for local and national economic development such as fisheries, shoreline stability, and resource sustainability hence they should be protected and conserved. In Kenya Mangroves were declared government reserve forests by the Proclamation No. 44 of 30th April 1932, and later by Legal Notice No. 174 of 20th May 1964. Under this “Gazette Notification for Mangrove Forests in Kenya” all land between high water and low water marks (ordinary spring tides) are described as mangrove areas. These forests cover about 61,279ha representing approximately 3% of the natural forest cover or less than 1% of the national land area. Mangrove forests are found in tidal estuaries, creeks, and protected bays along the 536 km long Kenyan coastline that extends from the Kenya-Tanzania border in the south to the Kenya-Somalia border in the north; between latitudes 1°40΄S and 4°25΄S and longitudes 41°34΄E and 39°17΄E. Mikoko (Mangrove in Swahili) is the first project specifically developed for mangrove areas in Kenya. Driven by the Kenya Forest Service, the project takes into account the recommendations of the National Mangrove Ecosystem Management Plan 2017-2027. For effective management of mangroves in the country, the Plan is organised around six programmes including; forest conservation and utilization; fisheries development and management; community; tourism development; research and education; and human resource and operations. These programmes prescribe measures for rehabilitation, conservation, and sustainable management of mangrove ecosystems in Kenya. Implementations of this Plan will be led by Kenya Forest Service (KFS); but will also include other key actors such as Kenya Wildlife Service, State Department of Fisheries, Research Institutions, Academia and Community Forest Associations through a specially constituted National Mangrove Advisory Committee. The project is for a 2-year period during which it shall develop an effective system for management of mangrove resources in Kenya. This will be done through the development of management prescriptions, skills improvement and provision of adequate infrastructure as recommended by the mangrove plan. Biodiversity information on mangroves, covering species descriptions and distribution, is essential for understanding the ecology and distribution of this endangered ecosystem and its management. Nowadays, very few is done in that domain. If the mangroves location are well know, it's not the case regarding the species distribution. Citizen science is a way to address this important issue. MIKOKO, a French FSPI funded project, is focused on Kenya to develop species information systems on mangrove species. Mikoko aims to assimilate knowledge through its participatory portal to strengthen a science and technology network of stakeholders such as scientists and parataxonomists in the African region. The portal platform will contain a Citizen Science module, a graphic driven species identification module, a species pages module conforming to Species Profile Model and a spatial module. Subscribing to open data paradigm, all the data on the portal will be covered by Creative Commons license framework. Mobile applications for identifying 60 plant species and contributing to citizen science module will be deployed. The oral presentation will expose the portal features and related apps seeking participation from the environmentalists from the African region.

Perception and Participation of Fishermen in The Sustainable Management of Mud Crabs on The Outermost Small Island (Case Study : Enggano Island, Bengkulu Province, Indonesia)

Enggano Island is one of 111 small outermost islands in Indonesia and administratively belongs to the North Bengkulu Regency Bengkulu Province. Of 881 households, as many as 20.89% worked in the capture fisheries sub-sector. One species of capture fisheries which is the economic basis is mud crabs with an average production of 37.85 tons per year. In its life cycle, mud crabs are associated with mangrove ecosystems. This study aims to 1) examine the perception and participation of fishermen in the management of mud crabs and mangrove ecosystems on the small outer islands and 2) analyze factors that influence the participation of fishermen in the sustainable management of mud crabs and mangrove ecosystems in a sustainable manner. The analytical tool used is the Likert scale and multiple linear regression. The results showed that the perception of fishermen towards mud crabs was in a good category with a score of 3.46 and the perception of fishermen on mangrove ecosystems was in the very good category with a score of 4.23. The participation of fishermen in the sustainable management of mud crabs is categorized in the high category with the score of 3.81, and the participation of fishermen in the sustainable management of mangrove ecosystems is categorized in the very high participation category with the score of 4.35. Fishermen’s participation in mud crab management is influenced by perception of mangrove ecosystems and income as fishermen. The participation of fishermen in the sustainable management of mangrove ecosystems is influenced by perceptions of the mangrove ecosystem and the income of fishermen from other sources.

Economic analysis of management option for sustainable mangrove ecosystem in Tangerang District, Banten Province, Indonesia

Ecosystem services are very important for human life, but until now part of these ecosystems as a resource asset that contributes to the country’s economy has not been evaluated further. Mangrove ecosystems are one of the ecosystems that grow in alluvial sludge in coastal areas and river estuaries. They have a very important role to support fishery productivity as habitat of nursery and spawning grounds for aquatic biota. Based on those conditions, this study is directed to explore ecosystem services of ecology economic value to enhance mangrove sustainability. The analysis from data of 2017 on mangrove ecosystem of Tangerang District, Banten showed that the total economic value of mangrove ecosystems per hectare is IDR. 49.260.590,16. The analysis of optimal resource allocation can be concluded that optimal of mangrove area is 415,89 Ha with total economic value IDR.20.486.986.843,00. Conversion of mangrove ecosystems into several land changes will have an impact on the habitat that lives in it also has a negative effect on the income of coastal communities who use it, that have to be managed carefully. Economic valuations based on ecosystem services can enhance sustainable management of mangrove ecosystems and provide welfare to coastal communities who use them.

MAPPING AND CHANGE ANALYSIS IN MANGROVE FOREST BY USING LANDSAT IMAGERY

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

MAPPING AND CHANGE ANALYSIS IN MANGROVE FOREST BY USING LANDSAT IMAGERY

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

SUSTAINABILITY STATUS OF MANGROVE ECOSYSTEM MANAGEMENT IN SEMBILANG NATIONAL PARK, BANYUASIN REGENCY, SOUTH SUMATERA PROVINCE

he utilization of mangrove in Sembilang National Park area has increased lately so that it is necessary to assess the sustainability of the mangrove ecosystem management in the region. The study was conducted in March-April 2015. The research location was in the National Park Sembilang, Banyuasin Regency, South Sumatra. The study used primary data and secondary data collections. The primary data were collected from direct observation of mangrove vegetation and via directs interviews of 86 respondents using purposive sampling method. The sustainability status and recommendations for management strategies were determined using Multi Dimensional Scaling (MDS) method approaching by RAPFISH (Rapid Assessment Technique for Fisheries).Current sustainabilitystatus of mangrove management in Sembilang National Park, Banyuasin Regency, South Sumatra was "less sustainable" with multidimensional sustainability index of 49.81. Priority attributes that need to be fixed in order to improve the status of sustainable management of mangrove ecosystems in the region were area changes, local knowledge, conflict of interest, and local wisdom. Alternative strategy priority for mangrove ecosystem management in the region was the empowerment of local community for sustainable mangrove utilization. Keywords: sembilang national park, RAPMANGROVE, mangrove ecosystem management

Multi-Decadal Mangrove Forest Change Detection and Prediction in Honduras, Central America, with Landsat Imagery and a Markov Chain Model

Mangrove forests play an important role in providing ecological and socioeconomic services for human society. Coastal development, which converts mangrove forests to other land uses, has often ignored the services that mangrove may provide, leading to irreversible environmental degradation. Monitoring the spatiotemporal distribution of mangrove forests is thus critical for natural resources management of mangrove ecosystems. This study investigates spatiotemporal changes in Honduran mangrove forests using Landsat imagery during the periods 1985–1996, 1996–2002, and 2002–2013. The future trend of mangrove forest changes was projected by a Markov chain model to support decision-making for coastal management. The remote sensing data were processed through three main steps: (1) data pre-processing to correct geometric errors between the Landsat imageries and to perform reflectance normalization; (2) image classification with the unsupervised Otsu’s method and change detection; and (3) mangrove change projection using a Markov chain model. Validation of the unsupervised Otsu’s method was made by comparing the classification results with the ground reference data in 2002, which yielded satisfactory agreement with an overall accuracy of 91.1% and Kappa coefficient of 0.82. When examining mangrove changes from 1985 to 2013, approximately 11.9% of the mangrove forests were transformed to other land uses, especially shrimp farming, while little effort (3.9%) was applied for mangrove rehabilitation during this 28-year period. Changes in the extent of mangrove forests were further projected until 2020, indicating that the area of mangrove forests could be continuously reduced by 1,200 ha from 2013 (approximately 36,700 ha) to 2020 (approximately 35,500 ha). Institutional interventions should be taken for sustainable management of mangrove ecosystems in this coastal region.

Potential and management of mangrove ecosystem in South Jailolo Sub-district, West Halmahera, North Moluccas

Abstract. Taher MM, Kamal MM, Zairion. 2012. Potential and management of mangrove ecosystem in South Jailolo Sub-district of West Halmahera, North Moluccas. Bonorowo Wetlands 2: 19-30. Mangrove ecosystem in South Jailolo District has many functions for the coastal area. This is a concern because the extent of mangrove ecosystems decreases from year to year due to the exploitation and conversion for various purposes without considering the ecological and physical functions of mangrove ecosystems. This research aims to describe the potential and existing conditions of the mangrove ecosystem and give a directive policy strategy for managing the mangrove ecosystem in this area. This study aims to determine the condition of mangrove ecosystems in the District of South Jailolo, assessing the potential ecological and economic impacts of mangrove ecosystems and how significant a reduction in mangrove area over the past 17 years, and then set the strategy of sustainable management of mangrove ecosystems This research using primary and secondary data. Primer data gathering is done by sampling, field observation, questioner, the open interview ended, and in-depth interview in the research area—secondary data gathering by unraveling various literature and related institutions. Although the reduction in mangrove forest area is still in small quantities, to maintain sustainability and ecological function, it needs management strategies. Results of analysis for management strategies found that is conservation to preserve the mangrove ecosystem area (34%), managing the mangrove ecosystem as ecotourism (32%), conservation of mangrove land as aquaculture area (21%), and make local regulations for the management of mangrove ecosystems (13%).

Restoration and management of mangrove systems — a lesson for and from the East African region

The restoration of mangroves has received a lot of attention world wide for several reasons. Firstly, the long ignored ecological and environmental values of mangrove forests have been documented for many mangrove areas in the world. Secondly, there is a high subsistence dependence on natural resources from mangrove forests. In addition, large losses of mangroves have occurred throughout the world leading to coastal erosion, decline of fishery resources and other environmental consequences, some of which in need of urgent attention. Finally, governments throughout the world are showing commitments towards sustainable use of mangrove areas. This paper outlines the activities of mangrove restoration and management around the world with particular emphasis on Eastern Africa. As noted here, extensive research has been carried out on the ecology, structure and functioning of the mangrove ecosystem. However, the findings have not been interpreted in a management framework, thus mangrove forests around the world continue to be over-exploited, converted to aquaculture ponds, and polluted. We strongly argue that links between research and sustainable management of mangrove ecosystems should be established.

Distribution Pattern of Shrimps and Fish AmongAvicenniaandRhizophoraMicrohabitats in the Pagbilao Mangroves, Philippines

For sustainable management of mangrove ecosystems, there is a pressing need to increase our knowledge of fish and invertebrates associated with this system. This study sampled microhabitats (89–258m2) inside the mangrove forest at Pagbilao, the Philippines, on two consecutive spring tides using stake nets. Distribution patterns of shrimps and fish were compared among four microhabitats that differed in dominant mangrove species (Avicennia marina,A. officinalisorRhizophora apiculata), structural complexity of the root system, and proximity to open water habitat. A 5 to 6-year-old replantedRhizophoramicrohabitat was also sampled to study faunal recolonization following replantation. The mean (±SE) density of the shrimp community was 1·5±0·2 shrimpsm−2, dominated by Palaemonidae, followed byAcetessp.,Penaeus merguiensisandMetapenaeus ensis. The highest shrimp density was observed in the replantedRhizophorahabitat, which also had the highest structural complexity. The mean (±SE) density and biomass of the fish community was 5·1±2·0 fishm−2and 10·4±3·3gm−2, respectively, dominated byAmbassis kopsi,A. urotaeniaandAtherinomorus balabacensis. The fish community preferred the pneumatophore (Avicennia) microhabitats to the prop root (Rhizophora) habitats. Highest fish abundance and biomass were observed in the most inland habitat, which also lacked larger (total length >100mm) carnivorous fish. The results demonstrate the extensive use of intertidal mangrove forests by vagile fauna, as well as the successful recolonization by shrimps and fish of replantedRhizophorahabitat. The role of mangroves as predation refuges, based on the distribution pattern of shrimps and fish, is discussed. Sampling strategies in mangrove intertidal habitat are also outlined.