Ekologi dan Struktur Komunitas Lamun di Teluk Ratatotok, Minahasa Tenggara, Sulawesi Utara

Penelitian mengenai ekologi dan struktur komunitas lamun ini dilakukan tanggal 10 – 15 Juni 2013 di perairan pesisir Teluk Ratatotok, Minahasa Tenggara. Metode penelitian dilakukan secara purposive sampling terkait dengan keberadaan lamun. Penelitian yang dilakukan meliputi pengukuran prosentase tutupan lamun, kerapatan, struktur komunitas, dan kondisi lingkungan di lokasi penelitian. Terdapat tujuh jenis lamun yang terdiri dari dua famili. Famili Hydrocharitaceae ditemukan tiga jenis lamun yaitu Enhalus acoroides (Ea), Thalassia hemprichii (Th) dan Halophila ovalis (Ho). Empat jenis lamun dari famili Cymodoceaceae yaitu Cymodocea serrulata (Cs), Cymodocea rotundata (Cr), Halodule pinifolia (Hp), dan Syringodium isoetifolium (Si). Kisaran prosentase penutupan rata-rata antara 22,5% - 89,5%. Kerapatan lamun perstasiun berkisar antara 17 – 473 ind/m2, dengan kerapatan tertinggi lamun jenis Ho sebesar 473 ind/m2 di stasiun 6. Nilai INP tertinggi pada lamun jenis Ea sebesar 128% diikuti berturut-turut oleh Si (41%), Th (36%), Ho (27%), Cs (26%), Cr (24%) dan Hp (17%). Berdasarkan kriteria status kondisi padang lamun (Kepmen LH no 200 tahun 2004), kondisi padang lamun di Teluk Ratatotok antara rusak/miskin sampai dengan baik/sehat. Stasiun 5 kondisi rusak/miskin, stasiun 3 dan 4 kondisi rusak/kurang sehat dan tiga stasiun kondisi baik/sehat yaitu stasiun 1, 2 dan 6. Secara keseluruhan kondisi lingkungaan Teluk Ratatotok masih mendukung pertumbuhan lamun

Variability in the organic carbon stocks, sources, and accumulation rates of Indonesian mangrove ecosystems

Mangrove ecosystems are an important natural carbon sink that accumulate and store large amounts of organic carbon (Corg), in particular in the sediment. However, the magnitude of carbon stocks and the rate of carbon accumulation (CAR) vary geographically due to a large variation of local factors. In order to better understand the blue carbon sink of mangrove ecosystems, we measured organic carbon stocks, sources and accumulation rates in three Indonesian mangrove ecosystems with different environmental settings and conditions; (i) a degraded estuarine mangrove forest in the Segara Anakan Lagoon (SAL), Central Java, (ii) an undegraded estuarine mangrove forest in Berau region, East Kalimantan, and (iii) a pristine marine mangrove forest on Kongsi Island, Thousand Islands, Jakarta. In general, Corg stocks were higher in estuarine than in marine mangroves, although a large variation was observed among the estuarine mangroves. The mean total Corg stock in Berau (615 ± 181 Mg C ha−1) is twice as high as that in SAL (298 ± 181 Mg C ha−1). However, the Segara Anakan Lagoon displayed large within-system variation with a much higher Corg stock in the eastern (483 ± 124 Mg C ha−1) than in the central lagoon (167 ± 36 Mg C ha−1). The predominant accumulation of autochthonous mangrove organic matter likely contributed to the higher Corg stocks in Berau and the eastern SAL. Interestingly, the CAR distribution pattern in SAL is opposite to that of its Corg stocks. The central SAL that receives high sediment inputs from the hinterland has a much higher CAR than the eastern SAL (658 ± 311 g C m−2 yr−1 and 194 ± 46 g C m−2 yr−1, respectively), while Berau has one of the highest CAR (1722 ± 183 g C m−2 yr−1) ever measured. It appears that these large differences are driven by the environmental setting and conditions, mainly sediment dynamics and hydrodynamics, landform, and vegetation conditions. It is inferred that quantifying carbon accumulation in sediments is a useful tool in estimating the present-day carbon storage of mangrove ecosystems. This is a precondition for taking measures under REDD+ (Reducing Emissions from Deforestation and Forest Degradation and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries) schemes

Ekosistem Lamun Sebagai Bioindikator Lingkungan Di P. Lembeh, Bitung, Sulawesi Utara

Seagrass ecosystem has a function of spawning, nursery, and feeding ground. Besides, it could be used as a bio-indicator of environmental health. This study of seagrass ecosystem was done in 17- 22 May 2014 in Lembeh Island and Tanjung Merah, Bitung. The purpose of the study is to obtain existing condition of seagrass ecosystem and its role as environment bio-indicator. Purposive sampling method was used representing all study sites. Structure analysis of seagrass communities describes the existing condition, while scoring / weighting method estimate current condition of the seagrass. Results that show there are seven species of seagrass. In the stations opposite to Bitung mainland, 75% of the seagrass are Enhalus acoroides (10-50% covers). Importance value index of the seagrass species were Enhalus acoroides (231–300 %), Thalassia hemprichii ( 102–198 %) and Halophila ovalis (110 %) respectively. Based on the weighting method and environmental standard quality, seagrass ecosystem in Lembeh island opposite to Bitung mainland was in damage and unhealthy condition, while seagrass ecosystem opposite to the open sea was in a good and healthy condition. This was due to the domestic waste that is trapped in seagrass ecosystem in the study site. It is necessary to improve awareness to maintain quality of environmental

STUDI AWAL ANALISIS INTERAKSI LAUT-ATMOSFER PADA TEKANAN PARSIAL CO2 DI TELUK BANTEN

Teluk Banten yang terletak di Laut Jawa merupakan suatu daerah yang berpotensi untuk terjadi tekanan parsial karbon dioksida (pCO2) yang siginifikan akibat aktivitas sosial-ekonomi di daerah ini. Kajian awal ini merupakan analisis menggunakan data survei dari parameter-parameter oseanografik dan atmosferik. Hasil studi awal interaksi laut-atmosfer terhadap tekanan parsial CO2 di Teluk Banten memperlihatkan bahwa pCO2 yang tinggi berada di area open sea dan relatif berkurang mendekati arah muara. Kondisi ini disebabkan oleh kecepatan angin yang dapat mempengaruhi kondisi suhu dan elevasi permukaan laut, sedangkan profil salinitas di Teluk Banten memperlihatkan bahwa nilai salinitas tinggi ke arah open sea dan rendah ke arah teluk, sedangkan profil stratifikasi sampai kedalaman sekitar 12 meter tidak banyak berubah. Data pengukuran elevasi laut dengan mengindikasikan adanya pola asymmetric pasut diurnal (24 jam-an) dan pola pasut 8 jam-an. Pola Curah Hujan terhadap konsentrasi CO2 atmosfer pada data per bulan-an (monthly) menunjukkan bahwa pada musim penghujan 2007 (bulan Januari-Februari) Curah Hujan (CH) tinggi dan nilai CO2 juga tinggi khususnya di bulan Februari 2007, sedangkan di musim peralihan 2007 (Februari-Maret) CO2 menurun.   Banten Bay located in the Java Sea is a potential place for occurrence of significant partial pressure of Carbon Dioxide (pCO2) values due to the social-economic activities on this area. This preliminary study used analysis of survey data of oceanographic and atmospheric parameters. It provided pCO2 values were high at the open sea and relatively decreased close to the bay. This condition was caused by wind speed affecting to the temperature and surface elevation. Meanwhile the salinity profile gave high values at the open sea and lower values at the area close to the bay, while the stratification profile up to 12 meter depth did not change much. The sea elevation data indicated asymmetric diurnal and 8 hours tide patterns. During the rainy season 2007 (January-February) the monthly precipitation values and consentration of CO2 atmosphere values were strong while at the intra-seasonal time 2007 (February-March) these values were significantly small

Deteksi Perubahan Padang Lamun Menggunakan Teknologi Penginderaan Jauh Dan Kaitannya Dengan Kemampuan Menyimpan Karbon Di Perairan Teluk Banten

Ekosistem laut di Indonesia mempunyai potensi besar untuk menyerap CO2 sebagai gas utama penyebab pemanasan global yang berimplikasi pada terjadinya perubahan iklim salah satunya padang lamun. Tujuan penelitian ini adalah mengidentifikasi perubahan luasan dan klasifikasi lamun menggunakan teknologi penginderaan jauh serta mengkaitkannya dengan kemampuan menyimpan karbonnya di Perairan Teluk Banten. Pada penelitian ini dilakukan analisis perubahan lamun menggunakan data citra ALOS AVNIR-2 selama dua tahun (2008 dan 2010) dengan perbandingan ­post-classification. Algoritma yang digunakan pada pengolahan data adalah algoritma lyzenga sebagai koreksi kolom air. Berdasarkan hasil penelitian, luas ekosistem lamun pada peta hasil pengolahan data citra dengan nilai overall accuracy 57,69% untuk tahun 2008 mencapai 59,5 ha dan 46,8 ha untuk tahun 2010. Kondisi tutupan padang lamun di Perairan Teluk Banten untuk lokasi Pulau Panjang dan Tanjung Kepu masuk ke dalam kelompok status lamun “kurang rapat” sedangkan lokasi Pulau Kubur, Pamujan Besar, Pamujan Kecil dan Dermaga Bojonegara masuk ke dalam kelompok status lamun “jarang”. Untuk perubahannya mengalami penurunan luas area sekitar 2,9% atau 1,4 ha dimana tahun 2008 memiliki  area seluas 45,2 ha menjadi 43,8 ha pada tahun 2010. Keterkaitan simpanan karbon dengan luas area perubahan menunjukan bahwa adanya penurunan  potensi penyerapan dimana potensi penyerapan sebesar 0,0004 tonCha-1tahun-1 dari 0,0114 tonCha-1tahun-1 pada tahun 2008 menjadi 0,0110 pada tahun 2010.   Kata kunci : Lamun, Penginderaan Jauh, Karbon, Teluk Bante

Carbon, nitrogen and stable carbon isotopes in the sediment core E47 from Eastern Segara Anakan, Indonesia

What was sampled: Mangrove sediment Parameter measured and method: 1. Organic carbon (Corg), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 2. Total nitrogen (N), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 3. Stable carbon isotope composition (δ13Corg), analyzed using Thermo Finnigan Delta plus mass spectrometer coupled to a Flash EA1112 Elemental Analyzer Where was sampled: Eastern Segara Anakan Lagoon, Central Java, Indonesia When was sampled: Sediment samples were taken in December 2016. How it was sampled: Mangrove sediments were collected using a 1 m long semi-cylindrical auger. Sediments were taken down to 1 m depth, and were sampled in 5 cm interval

Carbon, nitrogen and stable carbon isotopes in the sediment core C43 from Central Segara Anakan, Indonesia

What was sampled: Mangrove sediment Parameter measured and method: 1. Organic carbon (Corg), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 2. Total nitrogen (N), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 3. Stable carbon isotope composition (δ13Corg), analyzed using Thermo Finnigan Delta plus mass spectrometer coupled to a Flash EA1112 Elemental Analyzer Where was sampled: Central Segara Anakan Lagoon, Central Java, Indonesia When was sampled: Sediment samples were taken in December 2016. How it was sampled: Mangrove sediments were collected using a 1 m long semi-cylindrical auger. Sediments were taken down to 1 m depth, and were sampled in 5 cm interval

Carbon, nitrogen and stable carbon isotopes in the sediment core K1 from Kongsi Island, Indonesia

What was sampled: Mangrove sediment Parameter measured and method: 1. Organic carbon (Corg), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 2. Total nitrogen (N), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 3. Stable carbon isotope composition (δ13Corg), analyzed using Thermo Finnigan Delta plus mass spectrometer coupled to a Flash EA1112 Elemental Analyzer Where was sampled: Kongsi Island, Thousand Islands Marine National Park, Jakarta, Indonesia When was sampled: Sediment samples were taken in December 2016. How it was sampled: Mangrove sediments were collected using a 1 m long semi-cylindrical auger. Sediments were taken down to 1 m depth, and were sampled in 5 cm interva

Carbon, nitrogen and stable carbon isotopes in the sediment core E46 from Eastern Segara Anakan, Indonesia

What was sampled: Mangrove sediment Parameter measured and method: 1. Organic carbon (Corg), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 2. Total nitrogen (N), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 3. Stable carbon isotope composition (δ13Corg), analyzed using Thermo Finnigan Delta plus mass spectrometer coupled to a Flash EA1112 Elemental Analyzer Where was sampled: Eastern Segara Anakan Lagoon, Central Java, Indonesia When was sampled: Sediment samples were taken in December 2016. How it was sampled: Mangrove sediments were collected using a 1 m long semi-cylindrical auger. Sediments were taken down to 1 m depth, and were sampled in 5 cm interval

Carbon, nitrogen and stable carbon isotopes in the sediment core B3 from Berau, Indonesia

What was sampled: Mangrove sediment Parameter measured and method: 1. Organic carbon (Corg), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 2. Total nitrogen (N), analyzed using elemental analyzer (Eurovector E3000 Elemental Analyzer) 3. Stable carbon isotope composition (δ13Corg), analyzed using Thermo Finnigan Delta plus mass spectrometer coupled to a Flash EA1112 Elemental Analyzer Where was sampled: Berau, East Kalimantan, Indonesia When was sampled: Sediment samples were taken in May 2013 How it was sampled: Mangrove sediments were collected using a 1 m long semi-cylindrical auger. Sediments were taken down to 1 m depth, and were sampled in 5 cm interval