Estimation of carbon stock in seagrass communities in Central Tapanuli

This study aims to determine the carbon stock in seagrass communities in Central Tapanuli, North Sumatera, Indonesia. The research was conducted from July to August 2020 in the coastal areas of Hajoran and Jago Jago. The parameters measured in this study were density, coverage, biomass, carbon content, and carbon stock in seagrass. Biomass analysis and carbon measurement are divided into the top (above-ground biomass) and the bottom substrate (below-ground biomass). Carbon measurements are conducted using the loss on ignition (LOI) approach. The results showed that the seagrass ecosystem on the coast of Central Tapanuli Regency, which was covered by monospecies Enhalus acoroides, was in a less healthy condition with a cover percentage of 30.3-33.3% and a density of 59-67 shoots/m2. Above-ground and below-ground seagrass biomass reached 140.19-188.72 g/m2 and 368.13-423.69 g/m2 respectively, while carbon stock reached 70.57-94.86 g Corg/m2 and 18731-19603 g Corg/m2 and total standing stock range 257.87-290.90 g Corg/m2. The data obtained from this research can be used as a database to see the potential of seagrass beds as storage of CO2 and as an effort to mitigate and adapt to climate change.

Potensi Kandungan Karbon Keragaman Spesies Lamun di Perairan Pesisir Selatan Lombok Timur

through the development of carbon zinc as an organic material produced from photosynthesis and stored and transported in the form of seagrass vegetation biomass. Seagrass is one of the aquatic vegetation that is able to absorb and store carbon. Seagrasses have the ability to absorb carbon through the process of photosynthesis. The purpose of this study was to describe the potential carbon content of seagrass species in the South Coastal Waters of East Lombok. This type of research is an expolarative descriptive research. The research method is a quadratic transect method. The population of this study were all seagrass species contained in 3 research stations. The collected data was then analyzed using analysis of seagrass species composition, seagrass cover, seagrass density, diversity, uniformity, dominance and analysis of carbon content through seagrass stand biomass (leaves, rhizomes/stems and roots). The result of this research is the discovery of 9 species of seagrass on Lungkak Beach and 5 species of seagrass on Gili Kere and Poton Bakau. The species density in the three study sites ranged from 0.09 to 56.91 stands/m2. Seagrass biomass values ranged from 1.47-261.9 gbk/m2 and total carbon content ranged from 295.91±202.88 gC. The value of this biomass and carbon content was dominated by seagrass species with large morphology such as Enhalus acroides, Thalasia hemprici, Cymodocea rotundata, and Cymodocea cerillata and high density and cover values of seagrass. The relationship between seagrass cover and seagrass carbon has a significant relationship where the higher the seagrass cover, the higher the carbon content of the seagrass.

Biomasa dan Simpanan Karbon pada Ekosistem Lamun di Perairan Batulawang dan Pulau Sintok Taman Nasional Karimunjawa, Jepara

Ekosistem lamun memiliki fungsi ekologi dan ekonomi yang tinggi. Peran ekosistem lamun dalam penyimpanan karbon akan tetapi masih belum menjadi sorotan. Tujuan dari penelitian ini yaitu untuk mengetahui nilai biomassa dan estimasi simpanan karbon pada ekosistem lamun di Perairan Batulawang, Pulau Kemujan serta Pulau Sintok, Taman Nasional Karimunjawa. Penelitian ini dilaksanakan pada 7 – 14 Noevmber 2019 di Perairan Batulawang dan Pulau Sintok, Taman Nasional Karimunjawa. Metode penelitian di lapangan menggunakan metode SeagrassWatch, sementara nilai biomassa dan nilai estimasi simpanan karbon dihitung menggunakan metode Metode Loss of Ignition (LOI) di laboratorium. Data yang diperoleh berupa pengukuran berat kering untuk menghitung biomassa dan analisa kandungan karbon pada lamun dan sedimen. Hasil penelitian didapatkan empat jenis lamun di Perairan Batulawang yaitu Enhalus acoroides, Thalassia hemprichii, Cymodocea serrulata, dan Thalassodendron ciliatum sedangkan di Pulau Sintok terdapat tiga jenis lamun yang ditemukan yaitu Thalassia hemprichii, Cymodocea rotundata, dan Halophila ovalis. Nilai total biomassa lamun terbesar pada Perairan Batulawang yaitu Enhalus acoroides dengan nilai 849,75 gbk/m2 dan nilai total biomassa lamun terkecil Thalassodendron ciliatum dengan nilai 29 gbk/m2. Nilai total biomassa lamun terbesar pada Pulau Sintok yaitu Cymodocea rotundata dengan nilai 177,75 gbk/m2dan nilai total biomassa lamun terkecil Halophila ovalis dengan nilai 4,75 gbk/m2. Hasil pengukuran karbon lamun pada Perairan Batulawang yaitu 12,97 – 359,87 gC/m2­ dan 258,20 – 541,51 gC/m2 pada sedimennya. Hasil pengukuran karbon pada lamun di Pulau Sintok yaitu 2,35 – 85,80 gC/m2 dan 204,92 – 765,92 gC/m2 pada sedimen. Kandungan karbon paling besar terdapat pada bagian bawah substrat (below ground). Kandungan karbon pada bagian bawah substrat tidak terganggu oleh faktor lingkungan (gelombang, arus, dan ulah manusia) sehingga terakumulasi baik. Seagrass ecosystems have high ecological and economic functions. The role of seagrass ecosystems in carbon storage, however, has not yet been highlighted. The purpose of this study was to determine the value of biomass and estimated carbon storage in seagrass ecosystems in Batulawang waters, Kemujan Island and Sintok Island, Karimunjawa National Park. This research was conducted on 7 − 14 November 2019 in Batulawang waters and Sintok Island, Karimunjawa National Park. The research method in the field uses the SeagrassWatch method, while the biomass value and the estimated value of carbon storage are calculated using the Loss of Ignition (LOI) method in the laboratory. The data obtained were measurements of dry weight to calculate biomass and analysis of carbon content in seagrass and sediments. The result shows that there are four species of seagrass in Batulawang Waters, they are Enhalus acoroides, Thalassia hemprichii, Cymodocea serrulata, and Thalassodendron cliatum meanwhile in Sintok Island there are three species, they are, Thalassia hemprichii, Cymodocea rotundata, and Halophila ovalis. The measurement of carbon is done by using Loss on Ignition Method. The highest total seagrass biomass in Batulawang waters is Enhalus acoroides with a value of 849.75 gbk/m2 and the lowest total seagrass biomass is Thalassodendron ciliatum with a value of 29 gbk/m2. The highest total seagrass biomass on Sintok Island is Cymodocea rotundata with a value of 177.75 gbk/m2 and the lowest total seagrass biomass is Halophila ovalis with a value of 4.75 gbk/m2. The results of measurements of seagrass carbon in Batulawang waters are 12,97 – 359,87 gC/m2­ and 258,20 – 541,51 gC/m2 on the sediments. The result of seagrass carbon measurement in Sintok Island is 2,35 – 85,80 gC/m2 and 204,92 – 765,92 gC/m2 on the sediments. The largest carbon content is at the bottom of the substrate (below ground). The carbon content at the bottom of the substrate is not disturbed by environmental factors (waves, currents, and human activities) so that it accumulates well.

Seagrass Cholorophyll-a, Biomass and Carbon Algorithms Based on the Field and Sentinel-2A Satellite Data at Karimunjawa Island, Indonesia

Chlorophyll-a in seagrass biomass is functioned for the photosynthetic process and store the organic carbon in their biomass of the leaf, rhizome, and root. Ecologically has functioned as blue carbon in reducing global warming adaptation and mitigation strategy. The study aimed to explore seagrass species, chlorophyll-a content, biomass and carbon stock at Karimunjawa Island. Develop algorithms of the Sentinel-2A satellite data based on field seagrass chlorophyll-a, biomass and carbon and at Pokemon and Bobby beach Karimunjawa Island. Four species of seagrass found at Bobby and Pokemon beach are Holodule pinifolia with a density of 160.44 ind.m−2 , Enhalus acoroides with 26.22 ind.m−2, Halophila ovalis with 6.67 ind.m−2 and Thalassia hemprichii with 4.44 ind.m−2.The lowest seagrass chlorophyll-a is 5.854 mg.ml−1 found in H. pinifolia and the highest is 20.819 mg.ml−1found in E. acoroides at Pokemon beach. The range of seagrass chlorophyll-a at Bobby beach was 3.485 - 14.133 mg.ml−1 in T. hemprichii. The smallest individual biomass dry weight was found in T.hempirichii with 1.32 g.dry.weight per individu, and the biggest in E.acoroides with 6.98 g.dry.weight per individu. The highest seagrass biomass at Pokemon beach was in E. acoroides with 236.93 g.m−2 which has a wide leaf morphology and the lowest in H. pinifolia with 75.91 g.m−2 with the smallest leaf morphology. The range of seagrass biomass at Bobby beach is 97.62 - 264.48 g.m−2 which is dominated by T.hempirichii. The range of seagrass carbon was 109.63 - 136.82 gC.m−2at Pokemon beach, and in the range of 95.00 - 114.01 gC.m−2 at Bobby beach. Algorithm of seagrass chlorophyll-a = -36.308 (B3/B4)2 – 140.41(B3/B4) + 83.912 ; biomass = -7028.3 (B3/B4)2 + 14948 (B3/B4) – 7764.4; carbon = -17.529(B2/B3)2 + 143.82(B2/B3) – 5.3362 for Pokemon beach. Algorithm of chlorophyll-a = 455.02 (B2/B4)2 + 823.72 (B2/B4) + 375.48; biomass = -14699 (B3/B2)2 + 28395(B3/B2) – 13537; and carbon = - 0.001(B3/B4)2+ 0.209(B3/B4) - 10.203 for Bobby beach. The use of Band-2 (0.490 ????m), Band-3 (0.560 ????m) and Band-4 (0.665 ????m) Sentinel-2A satellite data in the development of seagras chlorophyll-a, biomass and carbon algorithm was found to be significant.

Dugong foraging behavior on tropical intertidal seagrass meadows: the influence of climatic drivers and anthropogenic disturbance

Foraging strategies of dugongs in tropical areas are not yet well understood, and that is particularly true for grazing of fast-growing pioneer seagrass meadows in the intertidal zones. In this study, we investigated the driving factors affecting the number of grazing tracks in intertidal seagrass meadows caused by small herds of dugongs in Balikpapan Bay, Indonesia. We investigated seven intertidal seagrass meadows for which the dynamics of seagrass biomass, the ratio aboveground to belowground biomass, and the number of grazing tracks were recorded and measured based on monthly intervals over a year. Seagrass features showed a significant relationship with wind speed, precipitation, desiccation time, the distance of the grazing sward to a residential area, and fishing activity based on multiple (generalized) linear models. While the intertidal seagrass meadows consisted of 5 species in total, only Halodule pinifolia patches were grazed. Dugong feeding tracks were found in four of the seven sites. The strong variation in the number of tracks throughout the year was significantly affected by seagrass biomass of seagrass, location and wind speed. Our results show how the interplay of site conditions related to both shelter (wind speed) and food availability (seagrass biomass) determines its suitability for dugongs.

Cadangan Karbon pada Ekosistem Padang Lamun di Siantan Tengah Taman Wisata Perairan Kepulauan Anambas

Secara global, ekosistem lamun dianggap sebagai penyerap karbon sehingga dapat berkontribusi terhadap mitigasi perubahan iklim. Penelitian bertujuan untuk mengetahui komposisi jenis, biomassa dan cadangan karbon pada komunitas padang lamun di perairan Siantan Tengah Taman Wisata Perairan (TWP) Kepulauan Anambas. Penelitian dilaksanakan pada bulan Agustus 2019 s.d Januari 2020. Uji kandungan karbon dilakukan dengan metode Welkley and Black sedangkan untuk mendapatkan biomassa menggunakan metode gravimetrik. Hasil penelitian menunjukkan bahwa terdapat tiga jenis lamun, yaitu Enhalus acoroides, Thalassia hemprichii, dan Cymodocea rotundata. Nilai biomassa lamun berkisar antara 171,89 – 275,68 gbk/m2 dan nilai cadangan karbon berada pada kisaran 51,89 – 80,66 gC/m2. Padang lamun di Siantan Tengah memiliki luas 130,45 ha, sehingga total Cadangan karbon pada ekosistem padang lamun di perairan Siantan Tengah diperkirakan 95,88 ton C. Penelitian ini membuktikan adanya kandungan karbon pada biomassa lamun sehingga dapat disimpulkan bahwa padang lamun berperan sebagai penyerap karbon (carbon sink). Globally, seagrass ecosystems are considered as carbon sink so that it can contribute to climate change mitigation. This research aims to determine the species composition, biomass, and carbon stock in seagrass communities in Siantan Tengah Marine Tourism Park of Anambas Islands. The research was conducted in Agustus 2019 – January 2020. The carbon content test was carried out by the Walkley and Black method while to obtain biomass using the gravimetric method. The result od study showed that there are three species of seagrasses, namely Enhalus acoroides, Thalassia hemprichii, and Cymodocea rotundata. Seagrass biomass value range 171,89 – 275,68 gbk/m2 and seagrass carbon stock value range 51,89 – 80,66 gC/m2. The area of seagrass beds in Central Siantan is 130,45 ha so that the total carbon stock estimated reach 95,88 tons C. This research proves the presence of carbon in the biomass of seagrass beds, so it can be concluded that seagrass beds act as carbon sinks.

Density and Biomass of Seagrass Beds and Its Threats on Lamongan Regency

This study aimed to determine the density of seagrass species, seagrass biomass, and threats faced by seagrass communities in the Coastal District of Lamongan. The study was conducted from August to November 2019 in three coastal villages of Lamongan Regency, namely Tunggul Village (Station 1), Kranji Village (Station 2), and Banjarwati Village (Station 3). Furthermore, the stages of the study consisted of preparation, data collection on density, threat data, seagrass stand samples, sample processing, and data analysis. The results showed that the total density of seagrass species at Stations 1, 2, and 3 was 160 stands/m2, 172 stands/m2, and 185 stands/m2, respectively. Moreover, the total biomass of seagrass at Stations 1, 2, and 3 was 4633 g/m2, 2136 g/m2, and 9234 g/m2, respectively. In addition to seagrass species, seagrass density values also affected seagrass biomass. As development progresses in Lamongan Regency, it is known that the biggest threat of seagrass communities in the study site is human activity (anthropogenic), especially the anchor ships when anchored and the use of coastal areas as tourist areas. This occasion often cleans up seagrass communities because they are deemed unfit to be enjoyed tourism sector.

Estimasi Stok Karbon Padaekosistem Lamun Di Perairan Utara Papua (Studi Kasus : Pulau Liki, Pulau Befondi Dan Pulau Meossu)

One of the ecological functions of the seagrass ecosystem is the ability to absorb carbon coming from the atmosphere. The ability of seagrass to absorb carbon is carried out through photosynthesis. The absorbed carbon will then be stored in the form of seagrass biomass in the seagrass body. This study aims to estimate the carbon stock content stored in seagrass ecosystems in the Northern waters of Papua including on Liki Island, Befondi Island, and Meossu Island. The calculation of carbon stock is done by converting seagrass biomass using constants derived from representative values of seagrass carbon content in Indonesian waters. In general, based on the results obtained indicate that the biomass at the bellow ground of the seagrass is greater than the biomass at above ground the seagrass. The value of organic carbon content in seagrasses is influenced by seagrass biomass. The carbon stock content in the seagrass ecosystem in the study area is in the range of 18,04 – 419,46 g C / m2. Stations on Liki Island have generally higher carbon stocks compared to stations on other islands.Salah satu fungsi ekologi dari ekosistem lamun yaitu memiliki kemampuan dalam menyerap karbon yang berasal dari atmosfer. Kemampuan lamun dalam menyerap karbon dilakukan melalui proses fotosintesis. Karbon yang terserap selanjutnya akan disimpan dalam bentuk biomassa lamun pada tubuh lamun. Penelitian ini bertujuan untuk mengestimasi kandungan stok karbon yang tersimpan pada ekosistem lamun di Perairan Utara Papua tepatnya di Pulau Liki, Pulau Befondi dan Pulau Meossu. Perhitungan stok karbon dilakukan dengan melakukan konversi biomassa lamun menggunakan konstanta yang berasal dari nilai representatif konsentrasi kandungan karbon pada lamun yang berada di Perairan Indonesia. Secara umum berdasarkan hasil yang diperoleh menunjukkan bahwa biomassa pada bagian bawah lamun lebih besar dibandingkan dengan biomassa pada bagian atas lamun. Nilai kandungan karbon organik pada lamun dipengaruhi oleh biomassa lamun. Kandungan stok karbon pada ekosistem lamun di wilayah penelitian berada pada kisaran 18,04 – 419,46 gC/m2. Stasiun yang berada di Pulau Liki memiliki stok karbon yang umumnya lebih tinggi dibandingkan dengan stasiun yang berada di pulau lainnya.