Mangrove Density Research Articles

Diversity of bivalves on the north coast of Lamongan, East Java, Indonesia

Abstract. Atlanta V, Ambarwati R, Rahayu DA, Mujiomo N. 2022. Diversity of bivalves on the north coast of Lamongan, East Java, Indonesia. Biodiversitas 23: 4263-4271. Biodiversity in Indonesian waters is very abundant, one of which is bivalves. This study aimed to analyze the diversity, abundance, uniformity and dominance of bivalves, as well as to analyze the habitat profile of bivalves in the North Coast of Lamongan. Bivalves sampling was carried out at Kutang Beach and Joko Moersodo Beach. There were three research stations consisting of three sub-stations on each beach. At each sub-station, it was taken the plot of 5×5 m. Each plot contained five subplots of 1×1 m. The habitat profiles studied were temperature, pH, salinity, and turbidity and the type of substrate. Samples were identified based on morphological characters. The research data obtained were analyzed descriptive qualitatively. The results revealed that the bivalves found in the North Coast of Lamongan included Anadara antiquata, Vasticardium elongatum, Donax faba, Asaphis sp., Gari elongata, Serratina perplexa, Gafrarium pectinatum, Heterocardia gibbosula, Marcia hiantina, Marcia japonica, Marcia opima, Meretrix sp., and Venerupis aspera. The index value of bivalves’ diversity at the North Coast of Lamongan was 1.13-2.201. The habitat profile of the bivalves in the North Coast of Lamongan was as follows: temperature 29.3-31.7ºC, salinity 25-32 ppt, pH 7.59-8.18, turbidity 10.6-17.3 NTU and the dominant type of substrate was sandy mud. Bivalves were more commonly found on beaches with dense mangroves.

Mangroves Cover Change Trajectories 1984-2020: The Gradual Decrease of Mangroves in Colombia

Awareness of the significant benefits of mangroves to human lives and their role in regulating environmental processes has increased during the recent decades. Yet there remains significant uncertainty about the mangrove change trajectories and the drivers of change at national scales. In Colombia, the absence of historical satellite imagery and persistent cloud cover have impeded the accurate mapping of mangrove extent and change over time. We create a temporally consistent Landsat-derived dataset using the LandTrendr algorithm to track the historical land cover and mangrove conversion from 1984-2020 across Colombia. Over this period, mangrove extent decreased by ~48.000ha (14% of total mangrove area). We find a gradual reduction of mangrove extent along the Pacific coast since 2004, whereas, in the Caribbean, mangrove cover declined around during 1984-1988 and also after 2012. Our time-series analysis matches with drivers of mangrove change at three local sites. For instance, hydroclimatic events, dredging activities, and high sediment loads transported by the rivers have collectively improved mangrove recovery in some sites. In contrast, human activities pressure linked to agricultural expansion and road construction have degraded mangroves. The transition from dense mangrove to other vegetation types is the most significant conversion affecting mangrove cover in Colombia, impacting an area of 38,469 ± 2,829 ha. We anticipate increased mangrove loss, especially along the Pacific coast, resulting from intensified human activity. Prioritization of conservation areas is needed to support local institutions, maintain currently protected areas, and develop strategies (e.g. payment for ecosystem services) to preserve one of the most pristine mangrove regions in the Western Hemisphere.

Spatial Analysis of Mangrove Distribution Using Landsat 8 Oli in Badung Regency and Denpasar City, Bali Province, Indonesia

Bali is an island situated among the Indonesian archipelago with huge potential to host mangrove forests. Using remote sensing technology advances, satellite images, such as Landsat images, might be employed to analyse mangrove forest distribution and density. This paper presents an analysis of mangrove distribution in Badung Regency and Denpasar City, Bali, as a basis for the management and conservation of mangrove ecosystems. This study used Landsat 8 OLI images and a vegetation index to analyse the mangrove forest distribution and density in this area. It started by identifying mangrove forests using the RGB 564 band and continued to distinguish between mangrove and non-mangrove objects using unsupervised classification, before analysing mangrove density using the NDVI formula. The results show that the mangrove forest area in 2020 was 1,269.20 ha, with an accuracy rate of 83%. Mangroves were found on the deepest or most curved coastline of the Benoa Bay area, on enclosed waters. This distribution follows the river network in the lower reach, which has thick deposits and is uninfluenced by large currents and waves. Based on the vegetation index analysis results, the mangrove forest area observed mainly had a moderate density, with a total area of 510.85 ha (40%), followed by high density (413.15 ha/ 33%) and low density (340.51 ha/ 27%).

The System Dynamic of Mangrove Ecotourism of “Kampung Blekok” Situbondo East Java Indonesia: Economic and Ecological Dimension

Mangroves that grow in coastal areas have ecological and economic values. Research on the behavior of a mangrove ecotourism system is needed as a basis for management to provide sustainable benefits. This study aimed to describe the conceptualization of a mangrove ecotourism system, formulate a mangrove ecotourism model and formulate a scenario for Kampung Blekok mangrove ecotourism in Situbondo Regency. This study used a quantitative analysis with a dynamic system approach to see the behavior of the ecotourism system on the economic and ecological dimensions. The research results on the conceptualization of the ecotourism system with causal loop diagrams showed that the economic subsystem was composed of response variables in the form of ecotourism management income and community business income in ecotourism areas and gross regional domestic product. Meanwhile, the ecological subsystem consisted of response variables in mangroves’ death, planting, and rehabilitation. Model formulation with stock-flow diagrams demonstrated the relationship between response variables to explain the system. In the economic subsystem, the variable of community business acceptance had the highest sensitivity that could affect ecotourism income. While in the ecological subsystem, the highest sensitivity was on the variable of mangrove planting, which could affect the density of mangroves. The combination of economic subsystem scenarios optimized tourist visits and streamlined spending. The combination of ecological subsystem scenarios that became the priority was the addition of mangrove seedlings and controlling pests that caused the death of mangrove seedlings. Stakeholders are expected to synergize with each other in managing activities in ecotourism. Apart from exploiting their economic potential, the community and the private sector are also expected to participate in maintaining compliance with regulations to preserve mangroves. The government should monitor and enforce regulations related to ecotourism and support the development of mangrove ecotourism so that its benefits are sustainable.

Mangrove Habitat Assessment in Lavezares Northern Samar

Mangrove resources of the Municipality of Lavezares, Northern Samar were estimated with a total aggregate area of 1,038.4274 hectares, the 53.12% of which are distributed along the coastal margins in mainland and 46.88% along islands of the municipality. The mangal forests comprised of 13 true mangrove species belonging to seven families, which was predominantly of Rhizophoraceae combined with significant populations of Sonneratia and Avicennia species. The mangrove density varies at different sampled sites ranging from the least density of 2,100 to the densest of 24,900 stems per hectare. Six of the 12 mangrove sites have predominantly matured trees, an indicator of primary growth and six were of secondary growth with an average regenerative capacity of 72.60% of its populations.
 Bakauan bankau (Rhizophora stylosa) has the highest density of 840 trees per hectare with a relative density of 35 percent followed by Api-api (Avicennia officinales) with density of 507 trees per hectare with relative density of 21 percent. Other densities include Pagatpat (Sonneratia alba) with 453 trees per hectare and 19 percent relative density. Bakauan lalake (Rhizophora apiculata has the least density of 267 with relative density of 12 percent. 
 For purposes of determining the number of saplings/wildlings in the study area, the mangrove assessment team established 3 regenerative plots (1m x 1m) per quadrat.
 The use of acquiring data on the number of saplings in mangrove assessment is to provide information whether the area could regenerate naturally or it needs to have interventions like assisted natural regeneration or reforestation.
 Based on the findings, there were only 41 saplings/seedlings encountered in all quadrats during the assessment. It implies that the area is not capable of regenerating itself naturally. Intervention like assisted natural regeneration through enrichment planting is necessary.
 Assisted natural regeneration is the human protection and preservation of natural tree seedlings in forested areas like mangroves and improvement of the percentage of desirable species or genotypes and increasing biodiversity in a forest by interplanting.

ESTIMASI SERAPAN KARBON PADA SUBSTRAT DASAR BERDASARKAN TINGKAT KERAPATAN MANGROVE DI KAWASAN EKOWISATA LANTEBUNG KOTA MAKASSAR

The purpose of this study was to determine the density level of the mangrove ecosystem and to determine the absorption capacity of CO2 gas per hectare on the basic mangrove substrate found in the Lantebung Ecotourism Area, Makassar City. This research was conducted in July-December 2021 in the Lantebung Ecotourism Area, Makassar City. This study uses the Field Observation method to observe, measure and collect data, including primary and secondary data. Analysis of mangrove ecosystem density data and analysis of carbon uptake of mangrove substrates using the help of statistical data processing programs. Based on the results of the study, it shows that density can affect the amount of biomass, carbon stock content and CO2 absorption which has a strong relationship. The density of mangroves in plots I, II, and III (land-sea) has a higher density; The higher the density, the greater the total carbon stock and the ability to absorb CO2 gas per hectare in a mangrove ecosystem; Carbon content, carbon stock, and CO2 absorption capacity in mangrove ecosystems are higher at the surface than at depth but fluctuate up and down at each depth level.

Diversity and abundance of water birds in the mangrove area of south coast of Bangkalan, Madura Island, Indonesia

Abstract. Ramadhani A, Ambarwati R, Gumilang RS. 2022. Diversity and abundance of water birds in the mangrove area of south coast of Bangkalan, Madura Island, Indonesia. Biodiversitas 23: 3277-3284. The southern coastal mangrove area of ??Bangkalan, Madura Island, Indonesia, is an important bird habitat, especially for water birds. This study aimed to analyze the diversity and abundance of water birds in the southern coastal mangrove area of ??Bangkalan, Indonesia, as well as the environmental carrying capacity of this area as their habitat. Sampling was carried out using a birdwatching approach at four research stations. The diversity of water birds was analyzed using the Shannon-Wiener diversity index, while the abundance of water birds was calculated based on the abundance index. Environmental carrying capacity was analyzed descriptive-quantitatively based on the habitat profile. The results indicated that there were 15 species of water birds in the mangrove area belonging to five families in four orders, namely Charadriiformes, Ciconiiformes, Pelecaniformes, and Suliformes, with a diversity index of 1.547. There were three abundant species of water birds, namely the little egret (Egretta garzetta), Javan Pond-heron (Ardeola speciosa), and Great Egret (Ardea alba). In addition to water birds, there were nine species of arboreal birds in this area. The areas with dense mangroves provide better habitat carrying capacity for water birds compared to other coastal areas.

Mangrove Habitat Structure of Mud Crabs (Scylla serrata and S. olivacea) in the Bee Jay Bakau Resort Probolinggo, Indonesia

Mud crabs (Scylla serrata and S. olivacea) are important fisheries resources, but their population in nature is decreasing due to anthropogenic activities, like the deforestation of mangrove forests. Hence, it is crucial to conserve this marine biota for future sustainable use and to conserve our marine biodiversity. Conducting studies on the biological interactions of mud crabs in mangrove habitats can be one of the future conservation approaches. Accordingly, an analysis of the functional relationships between Scylla spp. abundance and the respective mangrove habitat have to be carried out. The research was conducted in the mangrove ecosystem of Bee Jay Bakau Resort Probolinggo (BJBR). Data were collected using line transects and quadrant transects. The Associations between mangroves and mud crab habitat structures were analyzed using the Correspondence Analysis (CA) method. The results show that the relationship matrix between Scylla spp. and the structure of the mangrove habitat is centered on the F1 and F2 factorial axes (89.22%). S. serrata of all size classes were associated with dense mangroves (≥15 trees per 100m2) and high salinities (3-4 ppt), while S. olivacea has shown to be associated with rare to very dense mangrove systems. It indicates that S. olivacea tends to have a higher adaptation rate than S. serrata in this mangrove system. This study will provide information and recommendation for the conservation management of mud crabs and mangrove ecosystems to conserve marine biodiversity.

Spatio-temporal of mangrove vegetation based on the analysis of multi-temporal sentinel-2 satellite imageries at Jepara Regency, Indonesia

Mangrove areas in the northern coast of Jepara Regency have been threatened by coastal erosion and changes in land use since 1980. These areas represent coastal ecosystems with significant ecological, biological, and economic importance. The status of these ecosystems needs to be monitored; the latest condition is important to local authorities. Rate of change in mangrove conditions can be used to forecast the future condition of these coastal areas. This study aims to determine the temporal changes in the area and density of mangrove vegetation in Jepara Regency in 2017 and 2020. This study applied analysis of Sentinel 2-A multitemporal satellite imagery and classification using random forest on the Google Earth Engine platform. It was found that the mangrove area shrank from 103 ha in 2017 to 95 ha in 2020. The vegetations showed that changes in mangrove area in Jepara Regency have decreased in the rare and dense mangrove density types. The density of rare and dense mangroves experienced a decrease in area of 6 and 5 hectares, respectively. No mangroves with dense cover were found in 2020. Meanwhile, mangroves with moderate cover experienced an increase in area of 3 hectares in 2020 compared to last year 2017.

Wave attenuation potential, sediment properties and mangrove growth dynamics data over Guyana's intertidal mudflats: assessing the potential of mangrove restoration works

Abstract. Coastal mangroves, thriving at the interface between land and sea, provide robust flood risk reduction. Projected increases in the frequency and magnitude of climate impact drivers such as sea level rise and wind and wave climatology reinforce the need to optimize the design and functionality of coastal protection works to increase resilience. Doing so effectively requires a sound understanding of the local coastal system. However, data availability particularly at muddy coasts remains a pronounced problem. As such, this paper captures a unique dataset for the Guyana coastline and focuses on relations between vegetation (mangrove) density, wave attenuation rates and sediment characteristics. These processes were studied along a cross-shore transect with mangroves fringing the coastline of Guyana. The data are publicly available at the 4TU Centre for Research Data (4TU.ResearchData) via https://doi.org/10.4121/c.5715269 (Best et al., 2022) where the collection Advancing Resilience Measures for Vegetated Coastline (ARM4VEG), Guyana, comprises of six key datasets. Suspended sediment concentrations typically exceeded 1 g L−1 with a maximum of 60 g L−1, implying that we measured merely fluid-mud conditions across a 1 m depth. Time series of wind waves and fluid-mud density variations, recorded simultaneously with tide elevation and suspended sediment data, indicate that wave–fluid-mud interactions in the nearshore may be largely responsible for the accumulation of fine, muddy sediment along the coast. Sediment properties reveal a consolidated underlying bed layer. Vegetation coverage densities in the Avicennia-dominated forest were determined across the vertical with maximum values over the first 20 cm from the bed due to the roots and pneumatophores. Generalized total wave attenuation rates in the forest and along the mudflat were between 0.002–0.0032 m−1 and 0.0003–0.0004 m−1 respectively. Both the mangroves and the mudflats have a high wave-damping capacity. The wave attenuation in the mangroves is presumably dominated by energy losses due to vegetation drag, since wave attenuation due to bottom friction and viscous dissipation on the bare mudflats is significantly lower than wave dissipation inside the mangrove vegetation. Data collected corroborate the coastal defence function of mangroves by quantifying their contribution to wave attenuation and sediment trapping. The explicit linking of these properties to vegetation structure facilitates modelling studies investigating the mechanisms determining the coastal defence capacities of mangroves.

Spatial multi-criteria analysis to capture socio-economic factors in mangrove conservation

Mangrove forests are among the most productive ecosystems, located in tropical and subtropical coastal waters and river estuaries. Mangroves benefit both people and the environment by providing shelter for brackish-water organisms, such as fish and shrimp. They form a green-belt area that protects land from abrasion and tsunamis, along with goods and services for people, e.g., fruit, fish and charcoal. However, unmanaged use of mangrove ecosystems has resulted in a widespread decline in their function and conflicts between users. A paucity of research on mangrove management and spatial zoning is also contributing to the decline of these ecosystems. This study develops a prioritisation process with Spatial Multi-criteria Analysis (SMCA) for social-ecological mangrove management, based on a case study in Baros, Yogyakarta, Indonesia. We include social (participation and perception), demographic, economic (economic value of mangroves) and ecological criteria (water quality, mangrove density and diversity, phytoplankton diversity and density) criteria and spatial considerations informed by remote sensing imagery. We consider the three different conservation scenarios of habitat protection areas, sanctuary areas, and restricted areas to help configure management plan options. We demonstrate how SMCA can support managers and policymakers in mapping conservation areas based on complex and diverse social-ecological data. However, further discussion with stakeholders in Baros is required to validate the produced map for future use. The involvement of stakeholders and governing bodies from the beginning or within the SMCA analysis will always be crucial in community-based prioritisations.

MACROZOOBENTHOS ASSOCIATED WITH MANGROVE ECOSYSTEMS IN DUMAI WATERS

Mangrove ecosystems are unique ecosystems found along the coast or river mouths that are still influenced by tides. Association is a process of interaction between organisms and their environment which is not simple but a complex process. One of the biota associated with mangroves is macrozoobenthos. This research was conducted in August 2021. The purpose of the study was to determine environmental conditions, mangrove species and density, macrozoobenthic species and density, and the relationship between macrozoobenthic density and mangrove forest density in Dumai waters. Based on the results of the study, the types of macrozoobenthos were found from the gastropod and bivalves classes. The type that is found in all stations is Nerita lineata. The highest density is at station III, which is 19.11 ind/m2. Mangroves in Dumai waters are classified as dense with the dominant species being Rhizophora apiculata and Xylocarpus granatum. The relationship between the density of macrozoobenthos and the density of mangroves belongs to the medium category

Community structure and potential carbon stock of mangrove forest in Malek Village, Paloh District, Sambas Regency, Indonesia

Mangrove forest in Sambas Regency is experiencing several pressures, both naturally and due to land use conversion into settlements, ponds and others. This study aims to analyze the structure of the mangrove community and the existing condition of mangrove forest in Malek Village, Sambas Regency. The research was conducted through vegetation analysis and a remote sensing approach. Estimation of carbon stock was done by using available allometric equations. Remote sensing data used in this study was from Sentinel-2 MSI image. The data was used to obtain information of the area and distribution of mangrove species. Results showed that there were two dominant true mangrove species at the site, namely Avicennia marina (IVI = 212.80) and Bruguiera gymnorrhiza (IVI = 187.20). Based on the results of the analysis, the area of mangrove in the location is 368.41 ha, with a dense category of 63.25%, medium 27.55%, and sparse 9.19%. The estimated value of above ground carbon stock of mangrove vegetation ranges from 23.09 ± 2.30 to 49.23 ± 2.59 Mg C ha-1. The mangrove forest area in Malek Village has good potential, it can be assessed from the density of mangroves, area, the thickness of mangroves, minimum damage, and potential carbon stocks stored.Indonesian title: Struktur komunitas dan potensi cadangan karbon di kawasan hutan mangrove Desa Malek, Kecamatan Paloh, Kabupaten Sambas, Indonesia

Characteristics and Carbon Storage of a Typical Mangrove Island Ecosystem in Beibu Gulf, South China Sea

By studying the structural characteristics and carbon storage of the mangrove island ecosystem in the Beibu Gulf, this study provides a scientific basis for mangrove ecological compensation in the coastal areas of Guangxi, South China Sea. On the basis of the unmanned aerial vehicle remote sensing images and a sample plot survey, the object-oriented multi-scale segmentation algorithm is used to extract the mangrove community type information, and one-way analysis of variance is conducted to analyse the structural characteristics of the mangrove community. The carbon storage and carbon density of different mangrove ecosystems were obtained based on the allometric growth equation of mangrove plants. The analysis yielded four main results. (1) The island group covers about 27.10 ha, 41.32% (11.20 ha) of which represents mangrove areas. The mangrove forest is widely distributed in the tidal flats around the islands. (2) The main mangrove types were Aegiceras corniculatum, Kandelia obovata + Aegiceras corniculatum, Avicennia marina + Aegiceras corniculatum and Avicennia marina communities. (3) Amongst the mangrove plants, Avicennia marina had the highest biomass (18.52 kg plant–1), followed by Kandelia obovata (7.84 kg plant–1) and Aegiceras corniculatum (3.85 kg plant–1). (4) The mangrove carbon density difference was significant. Kandelia obovata had the highest carbon density (148.03 t ha–1), followed by Avicennia marina (104.79 t ha–1) and Aegiceras corniculatum (99.24 t ha–1). The carbon storage of the mangrove island ecosystem was 1194.70 t, which was higher than in other areas with the same latitude. The carbon sequestration capacity of the mangrove was relatively strong.

Applying landscape approach in assessing effectiveness of mangrove conservation in Ca Mau Cape National Park, Vietnam

ABSTRACT The study aims to assess the effectiveness of mangrove conservation in Ca Mau Cape National Park (CMCNP) during 1973–2018 using remote sensing and landscape metrics. The maximum likelihood method was used to classify time-series Landsat images with overall accuracy ranging from 87.8% to 90.3% and Kappa from 0.83 to 0.88. Additionally, landscape structure which expresses the spatial pattern and the connections between landscape elements such as number, size, and shape were assessed using landscape metrics including Number of patches, Landscape Shape, Largest Patch, Cohesion, Core, Contiguity, and Contagion index. The results showed that mangroves increased by 1,078 ha (7%), and the landscape structure was simple in the first period (1973–1979). In the second period (1979–2003), mangroves decreased by 1,411 ha (9.2%) during 1989–1995, and then they increased by 4,564 ha (29.9%) from 1995 to 2003. The landscape structure was fragmented, disconnected, and had irregular shapes during the beginning but improved at the late phase. In the third period (2003–2018), mangroves increased by 1,596 ha (10.5%). In which, dense mangroves increased by 2,500 ha (16.4%). And sparse mangroves decreased by 904 ha (5.9%). The landscape structure was more homogenous and connected than the second period. Since CMCNP was established in 2003, mangroves have enlarged year by year. The landscape structure became more aggregated. These proved the effectiveness of mangrove conservation in both quality and quantity.

Analysis of organic content on sediment and mangrove density in mangrove conservation area, Mamburungan urban village, Tarakan city, Indonesia

The mangrove ecosystem in Mamburungan Village is known to have two dominant types of mangroves, namely Avicennia sp. and Sonneratia sp. The main factors that cause mangrove growth zoning are the type of substrate and the content of organic matter. This research was conducted through several stages, namely, determining the location, preparing tools and materials, taking sediment, and analyzing mangrove data. The highest organic matter content was found at station I of 2.53 % - 17.81 %, and the highest mangrove density ranged from 0.05 ind m-2 - 0.12 ind m-2 which was dominated by Avicennia sp. More organic matter content was found at a depth of 0 cm.

Carbon Sink Estimation of Mangrove Vegetation Using Remote Sensing in Segara Anakan, Cilacap

Highlight ResearchThe value of Leaf Area Index (LAI) and Normalized Different Vegetation Index (NDVI) have a strong relationship.Estimated mangrove leaf biomass and carbon stock in mangrove can be known through the Leaf Area Index (LAI) value.Each mangrove pixel can absorb the different carbon.Increasing the diameter of the tree trunk shows the more CO2 absorbed by the tree.AbstractWorldwide global warming occurs because of increasing carbon dioxide (CO2) in the atmosphere. Segara Anakan, the largest mangrove forest in Java Island, has the highest potential as a carbon sink in the tropics. This study aimed to quantify the area and density of mangrove forests in Segara Anakan and to estimate their potentials as carbon sink based on Sentinel-2A imagery. In this study, data from Sentinel 2A satellite imagery was processed and validated with field survey results. The results showed that Segara Anakan had mangrove forests covering an area of 5,481.64 ha in 2019 with the sparse density covered 706.92 ha, medium density covered of 2,526.80 ha, and high density covered 2,848.60 ha. The results of mangrove density were validated using Table Confusion Matrix and using correlation coefficient value (r) by comparing field measurement and Normalized Difference Vegetation Index (NDVI) algorithm. The accuracy for mangrove density was 86.92% with r-value 0.85. Mangrove in Segara Anakan has the ability to absorb 8.56 Mega gram of carbon per hectare. Segara Anakan mangroves have the potential to absorb high level of carbon, so we should maintain their sustainability.

Characteristics of Mangrove Forest in Anak Setatah Village Riau Province for Community-Based Tourism Village Development

The community in Anak Setatah Village has made efforts to conserve and rehabilitate mangrove forest ecosystems that have been damaged by abrasion, land conversion and mangrove forest encroachment. The TEGAS Community Group (Pokmas) established a mangrove nursery and planting business independently. The existence of mangrove forests that grow well can provide opportunities for the development of tourist villages. The aim of the research is to identify the characteristics of mangrove forests in Anak Setatah Village, Riau Province for the development of community-based tourism villages. The research uses survey methods, there are 3 (three) research locations, namely Station I of the mangrove tourism area (Dusun Karet settlement), Station II of the mangrove tourism area (mangrove forest conservation) and Station III of the mangrove tourism area (Dusun Karet beach). Research activities have been carried out in October 2021-January 2022. The results showed that the density of mangroves growing in the mangrove forest ecosystem of Anak Setatah Village, namely Station I, was 1122 ind/ha; Station II is 1799 ind/ha and Station III is 1289 ind/ha. Mangrove density at Station I and Station III is classified as medium category, at Station II is classified as very dense category. the results of the identification of mangrove vegetation in Station I obtained 2 species of mangrove (Avicennia alba and Avicennia marina); Station II obtained 4 mangrove species (Rhizophora apiculata, Rhizophora mucronata, Avicennia alba and Avicennia marina); and Station III obtained 2 species of mangrove (Avicennia alba and Avicennia marina). The results showed that the mangrove forest ecosystem in Anak Setatah Village had an average IKW value, namely the appropriate category (S2) with an average IKW value at Station I (61.84%); Very suitable category (S1) with an average IKW score at Station II (84.21%) and suitable category (S2) with an average IKW score at Station III (65.79%). Overall the three research stations have the characteristics of mangrove forests that grow well and the community plays an active role in preserving the mangrove forest so that it provides opportunities to be developed as a tourist village.

Sustainability of mangrove forest management in the former bauxite mining area on Bintan Island

Background : The bauxite mining area on Bintan Island continues to expand into the mangrove forest area. Mangrove forests have ecological, economic, and social importance, which must be managed accordingly to maintain their sustainability. This research was conducted to examine the sustainability of mangrove forest management in the former bauxite mining area on Bintan Island. Methods: The approach used is Multi Dimensional Scaling- Rapid Appraisal for Sustainability through the modified Rapfish ordinance software technique for the Mangrove Ecosystem. The type of data used is quantitative, covering five dimensions of sustainability, namely ecological, economic, social, legal and institutional as well as technology. Results: The results showed that the sustainability index status of the ecological, social, legal and institutional dimensions was quite sustainable, while the sustainability index of the economic dimension was unsustainable, and the technological dimension was less sustainable. Attributes of levers that are sensitive to the sustainability of mangrove forest management are: 1) Mangrove density, 2) Substrate fraction, 3) sedimentation, 4) Mangrove importance index, 5) Bio-concentration factor, 6) Benefit value direct, 7) Indirect benefit value, 8) Dependence on mangrove forest as a source of livelihood, 9) Corporate Social Responsibility funding support, 10) Community income, 11) Community health level, 12) Community perception, 13) Legality of mangrove area and mining, 14) Pollution monitoring technology in ex-mining areas and 15) Mangrove rehabilitation technology. Conclusions:The status of the mangrove forest sustainability index on Bintan Island is quite good. the economic and technological dimensions can be upgraded to sustainable status by carrying out management that is more focused on the lever attributes of the ecological, social, legal and institutional dimensions.

Mangrove seedling abundance in mangrove ecosystem outgrowth in Ajkwa Island, Mimika Regency, Papua

Mangrove is one of the essential ecosystems for coastal areas. Mangrove is an individual or community which survives in tidal areas. Ajkwa Island is an island created by sedimentation activities from Ajkwa river. Ajkwa Island has a tidal supply well and it makes this island be an essential area for mangrove growth. This research was conducted in Ajkwa Island, Mimika Regency, Papua Province. The research is in permanent monitoring plots in 2011, 2014, and 2018. Based on the research, 2 categories were found in the monitoring plot, there are seedling and herbs. Species for seedling category are Avicennia marina, Bruguiera gymnorrhiza, Bruguiera cylindrica, Diospyros sp., Nypa fruticans, Sonneratia alba, and Xylocarpus sp. Species for herbs category are Allamanda cathartica and Hoya sp. Mangrove ecosystem type in Ajkwa Island is over-wash mangrove. The result, Sonneratia alba and Bruguiera gymnorrhiza had density and important value index higher than the other species in every monitoring year. Mangrove spreading in Ajkwa Island increases in each monitoring year. Mangrove seedling spread significantly from 2014 to 2018. On the monitoring plots, mangrove density in 2014 is 41.700 ind/ha and for 2018 is 74.000 ind/ha. Beside vegetation analysis, this research does spatial analysis to support the result from field monitoring data. Spatial analysis also proved the spreading of the seedling increased significantly from 2014 to 2018.