The ecology of mangrove vegetation in Bintuni Bay, Irian Jaya, Indonesia

The ecology of mangrove forests on Potential Acid Sulphate soils at Bintuni Bay (132° 55' - 134° 02' E, and 2° 02' - 2° 97' S), Irian Jaya, Indonesia was studied. The annual rainfall is 3000mm and there is mixed semi-diurnal tide of 1-5.6m amplitude. The water has a varying salinity of 0-27%. Forest structure was studied in plots of 10m x 10m along three transects across Sikoroti Island and in three 50m x 50m plots in mixed Rhizophora - Bruguiera forest. All trees > 10cm trunk diameter were enumerated, measured and identified. Of the nine tree species, Rhizophora apiculata was the most dominant, followed by Bruguiera gymnorrhiza and Ceriops decandra. There was good regeneration seven years after clear-felling in plots on Amutu Besar and Amutu Kecil Islands. Small litterfall production, measured using ten 1m x 1m litter traps in each of the three 50m x 50m plots, was 11.09 t ha-1 y-1, and greatest during the wet season (December, 1.29 t ha-1 ) and least during the dry season (July, 0.61 t ha-1). The annual litterfall mineral element accession was (kg ha-1 y-1): N 240.4, P 6.1, K 43.2, Na 136.2, Ca 204.4 and Mg 48.7. Leaf decomposition of five species was studied in litterbags on the forest floor under trees of the same species. Sonneratia alba decomposed quickly with a half-life of 24 days, and Bruguiera parviflora was the slowest with a halflife of 124 days. Decomposition rates of all species followed a single exponential decay model. Leaf herbivory of young stands of Rhizophora apiculata and Bruguiera gymnorrhiza was significantly different among sites, species, plant height and leaf-age. Seed predation on six species was studied in three different sites. Twenty propagules of each species were secured by string in each of six 10m x 10m sub-plots within each of five 10m x 60m plots. On average 62.1% of the seeds were dead after 36 d. Predation was higher in the lower intertidal zone, and Avicennia alba and Bruguiera parviflora were the most predated. The results suggested that the Bintuni Bay mangroves can be sustainably managed but the best silvicultural system needs to be determined

STRUKTUR DAN KOMPOSISI VEGETASI MANGROVE DI DESA PANTAI MEKAR DAN PANTAI HARAPAN JAYA, KECAMATAN MUARA GEMBONG, KABUPATEN BEKASI, PROVINSI JAWA BARAT

Hutan mangrove merupakan komunitas tumbuhan khas yang berada di daerah peralihan antara ekosistem darat dan laut. Keberadaan ekosistem mangrove sangat menunjang keberlangsungan ekosistem di wilayah pesisir. Setidaknya terdapat tiga fungsi utama mangrove yaitu fungsi secara fisik, biologi, dan ekonomi. Tujuan penelitian ini untuk mengetahui struktur dan komposisi vegetasi mangrove di Desa Pantai Mekar dan Pantai Harapan Jaya, Kabupaten Bekasi. Penelitian dilakukan pada Bulan Agustus 2016, pada 7 Lokasi yaitu 2 Lokasi di Desa Pantai Mekar dan 5 Lokasi di Pantai Harapan Jaya. Pengambilan data vegetasi dilakukan dengan metode stratified random sampling. Setiap pohon (plot 10 m x 10 m) dan sapling (subplot 5 m x 5 m) diidentifikasi dan diukur diameternya setinggi dada (±1,3 m). Seedling dihitung keragaman dan penutupann subplot 1 m x 1 m. Hasil penelitian menunjukan paling sedikit 17 famili ditemukan dilokasi dan 23 spesies mangrove. Secara umum kerapatan pohon berkisar 1200 – 3300 ind/ha yang didominasi oleh Avicennia alba dan Avicennia marina. Distribusi diameter batang yang paling dominan pada kelas 4,0 – 17,9 cm, dan distribusi tinggi pohon pada kelas 5,5 - 7,9 m

MODEL PENGELOLAAN WILAYAH PESISIR BERBASIS EKOREGION DI KABUPATEN PEMALANG PROVINSI JAWA TENGAH

Pantai utara Jawa khususnya di Kabupaten Pemalang mengalami berbagai permasalahan lingkungan pesisir seperti kerusakan ekosistem, pencemaran, bencana banjir dan rob, penurunan tanah (land subsidence). Konsep ekoregion yang teritegrasi dalam perencanaan wilayah menjadi salah satu alternatif solusi terhadap permasalahan tersebut. Tujuan dari penelitian ini adalah: (1) memetakan ekoregion di wilayah pesisir Kabupaten Pemalang, (2) mengkaji keselarasan ekoregion pesisir dan penataan ruang di Kabupaten Pemalang, (3) mengkaji arahan pengelolaan pesisir berbasis ekoregion. Pemrosesan dan pengolahan data citra satelit menggunakan software ER Mapper 7.0, digitasi ekoregion dilakukan secara visual dan analisa keselarasan ekoregion dan penataan ruang dilakukan menggunakan softwareArc GIS 10.1. Verifikasi lapangan dilakukan pada beberapa lokasi terpilih pada tampilan citra satelit. Hasil penelitian menunjukkan bahwa ekoregion wilayah pesisir Kabupaten Pemalang tersusun atas dataran alluvial seluas 7.458,6 ha(62%), bentuk lahan antropogenik 1.470,2 ha (12%), dataran alluvial pantai1.275,7 ha (11%), dataran banjir 1.233,2 ha (10%) dan sisanya adalah estuaria, gisik pantai, gosong pantai, lagoon dan rawa payau masing-masing sebesar ± 117,4 ha (1%). Hasil analisis overlay keselarasan antara ekoregion dengan alokasi ruang yang ada saat ini menunjukkan bahwa sebesar 9.203,9 ha (72%) wilayah di pesisir kabupaten Pemalang selaras, sedangkan 3.125,7 ha (25%) perlu mendapat perhatian dan sebesar 396,3 ha (3%) tidak selaras dengan kondisi ekoregion pesisir saat ini. Pengelolaan ruang pesisir diarahkan untuk diselaraskan dengan kondisi ekoregion, untuk daerah yang kurang selaras maupun tidak selaras dapat dilakukan review terhadap kebijakan pemanfaatan ruang

Vulnerability Assessment of Mangroves using the Coastal Vulnerability Index in Timbulsloko Village, Sayung, Demak

The ongoing global warming is causing climate change in several regions of Indonesia, resulting in various impacts. One of these impacts affects coastal areas, namely, the rise in sea levels. The mangrove ecosystem is one of the coastal ecosystems with a crucial role in both ecological and economic aspects of life. This ecosystem is more susceptible to damage due to climate change and human activities. The purpose of this research is to determine the vulnerability level of the mangrove ecosystem, thereby serving as a reference for the rehabilitation of the mangrove ecosystem in Timbulsloko Village. The method used is descriptive exploratory, involving direct field measurements of oceanographic variables, such as salinity, substrate, and tidal data. The analysis employed was the Coastal Vulnerability Index (CVI) with scores divided into three categories: low, moderate, and high, with respective scores ranging between 0.45-2.31, 2.32-4.62, and 4.63-6.93. An analysis of the mangrove substrate was also conducted to determine the existing substrate types in Timbulsloko Village. The obtained results indicate that the salinity around the mangrove ranges from 29-30 ppt, the substrate type is characterized as mud, and the average tidal height is 1.5 m with a mixed leaning towards diurnal single tide. As a result, the vulnerability index value of the mangrove ecosystem in Timbulsloko Village is considered moderate, with a score of 3. The level of mangrove vulnerability is moderate, but sustainable management of the mangrove ecosystem is still required for the future.

KANDUNGAN LOGAM BERAT Hg DAN Pb SEDIMEN MANGROVE DI DESA PANTAI MEKAR DAN HARAPAN JAYA, KECAMATAN MUARA GEMBONG, KABUPATEN BEKASI

Logam berat Merkuri (Hg) dan Timbal (Pb) merupakan dua senyawa yang sudah terkandung secara alami di alam. Mangrove merupakan tumbuhan yang mampu hidup di wilayah pasang surut air laut. Mangrove juga merupakan penyerap polutan terbaik diwilayah estuari. Hg dan Pb apabila nilainya sangat tinggi di alam maka ada kejanggalan yang dimungkinkan karena adanya masukan dari luar. Sebagian besar pencemaran seringnya dilakukan oleh manusia sehingga meningkatkan kandungan logam berat di alam. Keberadaan logam berat tersebut dapat membahayakan bagi biota dan manusia. Penentuan stasiun menggunakan metode purposive sampling yang diharapkan hasil dari penelitian mampu mewakili seluruh wilayah penelitian. Sampel sedimen yang diambil merupakan sedimen permukaan ± 20 cm dengan berat ± 200 g yang dilakukan dengan 3 (tiga) kali ulangan pengambilan. Uji kandungan Hg menggunakan metode gravimetri, sedangkan untuk uji kandungan Pb menggunakan metode Spektrofotometri Serapan Atom (SSA) – nyala. Dari hasil yang didapatkan, kandungan Hg sedimen mangrove di Desa Harapan Jaya maupun Desa Pantai Mekar berkisar antara < 0,0007 mg/kg – 0,00535 mg/kg yang berarti masih dibawah baku mutu yang ditetapkan NIST RSM 1646a yaitu sebesar 0,04 mg/kg. Kandungan Pb sedimen mangrove di Desa Harapan Jaya dan Pantai Mekar berkisar antara 15,76 mg/kg – 24,27 mg/kg, hal ini menunjukkan bahwa seluruh stasiun yang ada di kedua desa sudah tercemar senyawa Pb karena ambang batas yang ditetapkan oleh NIST RSM 1646a sebesar 11,7 mg/kg

Struktur Komunitas Makrobentos Polychaeta Di Ekosistem Mangrove Desa Bedono Kecamatan Sayung Kabupaten Demak

Mangrove forest is a tropical coastal communities is dominated by several species of trees or characteristic shrubs that has the ability to grow in salty waters. The study aim was to describe structure community of Polychaeta Macrobenthos in the village of Bedono, district of Sayung, Demak Regency (06055\u2744”S - 110029\u2742”E) and has been conducted between April 2010 to September 2010. The area, due to its position in the northern coast of Java, has influence by Java Sea especially its long-shore current which in past decades has been changing due to the Semarang Port development. Effort has been made by OISCA, a Japan environmentally concerned NGO, to rehabilitate the area by planting mangrove even though the result is just still uncertain yet. This research was aimed to know the stucture of polychaeta macrobenthos communities Bedono Village, District Sayung, Demak Regency. This research used descriptive eksplorative method and while for the intake of sampel polychaeta conducted quantitative just taken that is only pursuant to volume unit. In this research, the location was divided into 4 stations, each with three replication of sampling transects. Intake sample conducted at fairish plot 1m x 1m with the deepness 10 cm. The result found 6 famili polychaeta : Nereidae, Amphiromidae, Eunicidae, Capitellidae, Arenicolidae, dan Acoetydae. There tedency that vegetation of mangrove progressively make abundance polychaeta very much

Studi Perubahan Luasan Vegetasi Mangrove Mengunakan Citra Landsat Tm Dan Landsat 7 Etm+ Tahun 1998 – 2010 Di Pesisir Kabupaten Mimika Papua

Mangrove ecosystem is one of kind forest that naturally influenced by tides. Mangrove root\u27s system have capability to hold and capture sediment transported by waves or currents which bring to sedimentation or soil formation arise and become the new land for mangrove vegetation. Tailings from the mining PT. Freeport Indonesia in Tembagapura cusher form of a smooth stone is passed through Aghawagon River, followed Otomona River and deposited in the Regional Deposition Ajkwa (DPA), the possibility of 5-10% of particles remaining Sand Mining (tailings) carried out the most subtle to the Estuary Ajkwa and the Arafura Sea (PT Freeport Indonesia, 1999). Sedimentation due to the flow of the remaining mine sand from the river and taken apart Ajkwa currents, thought to affect an area of mangrove forests that exist around the estuaries in the coastal Mimika. Aim of this study is determining the extent of vegetation change in Mimika coastal mangrove District, Papua during 1998 to 2010 using multitemporal satellite imagery. The study was conducted in November 2010 to May 2011 using 1998\u27s Landsat TM imagery, Landsat 7 ETM + in 2002, Landsat 7 ETM + in 2006, and Landsat 7 ETM+ 2010, by using descriptive method. The results of this study indicate changes in the extent of mangrove vegetation of the estuary area to Mawati Kamora is varied, ie, in the year 1998 to 2002 has improvement 250.64 ha and 234.91 ha of reduction, in the year 2002 to 2006 has improvement 131.82 ha and 193.37 ha of reduction, in the year 20006 to 2010 experienced a reduction of 175.94 ha and 89.28 ha. Supply of sediment input in the form of tailings or suspected influence on the addition of mangrove vegetation in the Mimika District coastal area of Papua, particularly in the area and Kamora Ajkwa River Estuary, while the reduction of mangrove vegetation in the Coastal area of Timika, Papua, probably caused from to hydrological factors of the currents and waves

Kajian Struktur Dan Komposisi Vegetasi Mangrove Di Kawasan Pesisir Desa Pasar Banggi, Kabupaten Rembang

The condition of an ecosystem mangrove in the Pasar Banggi appertain one of the best in northern coast in Central Java. Management mangrove ecosystem there begin since the 1960s with conduct rehabilitation especially independently by the community. This condition, is perceived as a good condition and could be a good example to be applied in other areas. The purpose of this study is to know about the structure and composition of mangrove vegetation in Coastal Pasar Banggi Village, Rembang District. Vegetation data taking based on purposive sampling method and every transect made sampling plot. Each tree (plot 10 m x 10 m) and sapling (subplot 5 m x 5 m) identified and measured on diameter at breast height (± 1.3 m). Seedling calculated the amount of each species and the percentage of cover on subplot 1 m x 1 m. The result of research in Pasar Banggi Village was found 11 mangrove species. Generally, tree mangrove in Pasar Banggi Village have the range of density 100 ind/ha – 2533 ind/ha which dominated by Rhizophora mucronata. The Index of diversity (H\u27) and Eveness (J\u27) of mangrove vegetation in Coastal Pasar Banggi Village, Rembang District, were in low category

Kajian Valuasi Ekonomi Hutan Mangrove Di Desa Pasar Banggi, Kecamatan Rembang, Kabupaten Rembang

Economi valuation is an instrument used to know a function of mangrove forest. The object of this research are to find out totalized economic valuation by means of direct valuation at mangrove area Pasar Banggi village, Rembang. Economic valuation can be able by totalized a direct use value, indirect use value, Option value and Existence value. Identification result at Pasar Banggi village are consist by four components there are, direct use values : Bandeng fishponds, saltponds, mangrove seeds, catching fishes, oyster and crab, indirect use values : breakwater as a resists of abration, option value : biodiversity, Existence value : habitats. The biggest value in this research is the resist of abration assumption as breakwater that is as bis as Rp.18.717.774.250-/year and total economic value from economis Pasar Banggi village, Rembang that is as big as Rp.19.610.846.229.-/year

VALUASI EKONOMI EKOSISTEM MANGROVE DI DUSUN BAROS, DESA TIRTOHARGO, KECAMATAN KRETEK, KABUPATEN BANTUL

Mangrove merupakan sumberdaya alam hayati yang penting di wilayah pesisir dan memiliki peran strategis bagi kehidupan baik secara fisik, biologis, dan ekonomis. Besarnya potensi ekosistem mangrove mendorong adanya ekploitasi sumberdaya yang berlebihan sehingga dapat mengancam kelestariannya. Bantul merupakan kabupaten di wilayah pesisir Daerah Istimewa Yogyakarta yang memiliki ekosistem mangrove buatan dan keberadaannya sudah semakin berkembang. Perkembangan mangrove di Dusun Baros membuat banyak pihak memberikan dukungan untuk ikut serta mengembangkan kawasan tersebut. Program-program pengelolaan dan pengembangan kawasan konservasi mangrove yang tidak memperhatikan fungsi ekologis justru akan merusak keberadaan mangrove dan dapat menimbulkan permasalahan tersendiri di masa mendatang. Penelitian ini dilakukan pada ekosistem mangrove di Dusun Baros, Desa Tirtohargo yang mempunyai tujuan yaitu, mengetahui kondisi dan status vegetasi mangrove, mengetahui nilai ekonomi total serta merumuskan strategi pengelolaan ekosistem mangrovenya. Metode yang digunakan untuk mendapatkan tujuan penelitian meliputi metode jalur dan petak, hemisperical photograpy, kuesioner, replacement cost, benefit transfer dan wawancara terstruktur yang kemudian dianalisis dengan SWOT. Hasil penelitian menunjukkan bahwa nilai analisis vegetasi di mangrove Baros didominasi oleh spesies Avicennia marina dan Rhizophora mucronata dengan kondisi baik dan tingkat penutupan kanopi yang padat sebesar 77,23 %. Nilai ekonomi total ekosistem mangrove Baros sebesar Rp. 177.750.777,-/ha/tahun yang terdiri atas nilai manfaat langsung, nilai manfaat tidak langsung, nilai manfaat pilihan dan nilai manfaat keberadaan. Alternatif strategi SWOT pengelolaan ekosistem mangrove di Dusun Baros yang menjadi prioritas adalah strategi SO (Strength-Opportunity). Kata kunci: Ekosistem mangrove di Dusun Baros, kondisi dan status, valuasi ekonomi, strategi pengelolaan Mangroves are biological natural resources that are important in coastal areas and has important function either physically, biologically and economically. The large potential of the mangrove ecosystem encourages excessive exploitation of resources which can threaten its sustainability. Bantul is a district in the Daerah Istimewa Yogyakarta provincy coastal area that has an artificial mangrove ecosystem and its existence has been growing. The development of Baros mangrove makes many parties provide support to participate in developing the mangrove conservation area. Management and development programs for mangrove conservation areas without regard to ecological functions will actually damage the existence of mangroves and this will create its own problems in the future. This research was conducted on the mangrove ecosystem in Baros Tirtohargo village which has the goal of knowing the condition and status of mangroves vegetation, knowing the total economic value and formulating the mangrove ecosystem management strategies in Baros. The methods used to obtain research objectives include path and plot methods, hemisperical photograpy, questionnaires, replacement costs, benefit transfers and structured interviews which are then analyzed by SWOT. The results showed that the value of mangrove vegetation analysis in Baros, Tirtohargo village was dominated by Avicennia marina and Rhizophora mucronata with good conditions and a solid canopy closure rate of 77.23%. The total economic value of Baros mangrove ecosystem is Rp. 177,750,777, - / ha / year consisting of the value of direct benefits, the value of indirect benefits, the value of the benefits of choice and the value of the benefits of existence. The alternative SWOT strategy for mangrove ecosystem management in Baros which is a priority is the SO strategy (Strength-Opportunity). Keywords: Mangrove ecosystem in Baros Tirtohargo village, conditions and status, economic valuation, management strategie