Estimasi Biomassa dan Simpanan Karbon pada Vegetasi Lamun di Perairan Pantai Jepara

Peningkatan emisi karbon yang berasal dari berbagai aktivitas manusisa dapat mengakibatkan terjadinya pemanasan global. Salah satu upaya untuk mengurangi emisi gas karbon adalah dengan memanfaatkan vegetasi pesisir seperti lamun yang dikenal dengan istilah blue carbon. Ekosistem lamun merupakan salah satu ekosistem pesisir yang dapat menyerap dan menyimpan karbon dalam jumlah yang besar dan dalam waktu yang lama. Penelitian ini bertujuan untuk mengetahui kerapatan, tutupan lamun, nilai biomassa dan simpanan karbon pada lamun di Pantai Blebak dan Pantai Prawean, Kabupaten Jepara. Metode survei dan penentuan lokasi dipilih dengan menggunakan metode purposive sampling, sedangkan metode pengambilan data lamun melalui metode line transect quadrant dengan ukuran 50x50 cm yang mengacu pada metode LIPI 2017. Perhitungan kandungan karbon menggunakan metode Loss On Ignition (LOI). Hasil kerapatan lamun total pada Pantai Prawean yaitu sebesar 221,45 ind/m2 dan nilai tutupan total lamun sebesar 45,98%. Kerapatan lamun total pada Pantai Blebak yaitu sebesar 160 ind/m2 dan nilai tutupan total lamun sebesar 41,67%. Nilai biomassa bawah substrat dan atas substrat pada Pantai Prawean (726,25 gbk/m2 dan 500,50 gbk/m2) menunjukkan nilai yang lebih besar dibandingkan nilai biomassa bawah substrat dan atas substrat pada Pantai Blebak (606,50 gbk/m2 dan 370,75 gbk/m2). Total kandungan karbon pada Pantai Prawean adalah 464,10 gC/m2 sedangkan pada Pantai Blebak adalah 357,79 gC/m2. Hasil perhitungan total stok karbon yang didapatkan menunjukkan bahwa Pantai Prawean memiliki nilai biomassa dan total stok karbon yang lebih tinggi daripada Pantai Blebak. Human activities lead to the increasing of carbon emission, which caused global warming. Seagrass and other coastal vegetation are being used to reduce carbon emission. This is known as blue carbon. The seagrass ecosystem is one of coastal ecosystem that can absorb and stock high amount of carbon in a short period of time. This study was done to determine the density, seagrass coverage, biomass, and carbon stock within the seagrass in Prawean and Blebak Beach, Jepara. Survey method and location determination method were done with purposive sampling method. Whereas, the seagrass data was collected by Line Transect Quadrant method 50x50 cm based on LIPI’s 2017 method. Loss on Ignition method was used to measure the carbon’s content. The density of total seagrass in Prawean beach is 221,45 ind/m2 and the total percentage of seagrass coverage is 45,98%. Total density of seagrass in Blebak Beach is 160 ind/m2 with a coverage percentage of 41,67%. The biomass below the substrate level and above the substrate level in Prawean Beach (726,25 gbk/m2 and 500,50 gbk/m2) showed a bigger amount than the amount of biomass in Blebak Beach (606,50 gbk/m2 and 370,75 gbk/m2). Total amount of carbon in Prawean is 464,10 gC/m2 meanwhile in Blebak, the amount of carbon is 357,79 gC/m2. The results of the total carbon stock obtained indicate that Prawean Beach has higher biomass and total carbon stock values than Blebak Beach.

Seagrass coverage and associated fauna at Gaya Island, Sabah, Malaysia: A pilot seagrass transplantation

Seagrasses provide a range of marine ecosystem services. These include coastal protection, biodiversity, provision of food for various organisms, breeding and nursery habitats for many marine species, and carbon storage. Increasing anthropogenic pressures have contributed to the decline of seagrass habitats. Transplantation is one of the solutions to increase seagrass coverage and resilience. What is often overlooked, however, is the ability of this tropical ecosystem to attract and support faunal assemblages that may impinge on the success of the transplantation. A pilot study on seagrass transplantation at Gaya Island (Kota Kinabalu, Sabah) was intended for observing its stability and species of fauna that develop association with this vegetation. The study covered the southwest and northeast monsoons. Mixed seagrass species were planted on approximately 50% of 30 m 2 transplantation areas. Monitoring of the planted seagrass was carried out in five phases (T1-T5) from September 2016 to April 2018. Weekly observations were made by SCUBA diving. Identification of associated fauna was done on the spot and was based on morphological characteristics. During the T1 (September to December 2016) the seagrass coverage was reduced to 41% due to strong waves generated by the northeast monsoon. However, the seagrass coverage increased ( 66 %) during the southwest monsoon (T2 - T4) in 2017. In early 2018 (T5), the seagrass coverage again reduced (about 18%) due to strong waves but recovered again at the end of the monitoring period (April 2018). A total of 30 species of fauna that were identified consisted of 9 resident and 21 non-resident species. Physical structure of transplanted seagrass created a microhabitat, and increased the food availability and abundance, which attracted many species of different trophic levels.

Current Status and Species Diversity of Seagrass in Panjang Island, Banten

Damage to seagrass beds in Panjang Island, Banten, has increased every year. The most significant decline occurred at an interval of 2000-2005 with a decrease of about 22.9 ha. Seagrass damage continued to increase at the year between 1989-2002 as a result of natural stone mining and coastal reclamation activities to become industrial areas and ports. The objective of this study was to determine the characteristics of the species and current status of seagrass communities in Panjang Island waters, Banten. Analysis of seagrass data included identification of species, frequency, density, percent coverage, and important value index. Based on these results, it was found three species of seagrass on Panjang Island, Banten, including species of Enhalus acoroides, Cymodocea serrulata, and Syrongodium isoetifolium. The percentage of seagrass coverage at five different research stations, the highest percentage of seagrass coverage was at station IV with a percentage of coverage of 48.94% and the lowest coverage was obtained at station V of 10.28%. The calculation of the importance value index (INP) of seagrass in Panjang Island waters, Banten, showed that the highest INP value was found in the Cymodocea serrulata seagrass species which was 41.47 and the lowest was found in the Syrongodium isoetifolium seagrass species which was 16.81. PCA analysis was also conducted to determine the relationship of seagrass density with chemical physics parameters. The results obtained showed the condition of seagrass ecosystems in Panjang Island waters, Banten, which was at a level of moderate to severe damage. The results of PCA analysis showed that water temperature, nitrate concentration, DO, and TSS greatly influenced the density of seagrass in these waters.

Simpanan Karbon Enhalus acoroides LF. Royle 1839 (Angiosperms: Hydrocharitaceae) di Pantai Gelaman dan Pantai Alang-Alang, Karimunjawa Jepara

ABSTRAK: Perubahan iklim disebabkan oleh berbagai aktifitas kegiatan manusia yang menghasilkan gas karbon diokasida ke atmosfer bumi yang akan berdampak pada pemanasan global. Ekosistem padang lamun memiliki kemampuan untuk menyerap dan menyimpan karbon dalam jumlah besar dari atmosfer yang dapat mengurangi emisi karbon. Tujuan penelitian ini untuk mengetahui kerapatan, tutupan lamun, biomassa dan simpanan karbon pada lamun Enhalus acoroides di Pantai Gelaman dan Pantai Alang-Alang. Penelitian menggunakan metode survei dan penentuan lokasi dipilih dengan menggunakan metode line transect quadrant yang mengacu pada metode LIPI. Sampling dilakukan pada titik 50 m setiap substasiun dengan metode pencuplikan. Pengukuran karbon pada sampel lamun menggunakan metode LOI.Kerapatan lamun di Stasiun 1 sebesar 1235 ind/m2 dan nilai tutupan lamun sebesar 68,76%. Kerapatan Stasiun 2 sebesar 1135 ind/m2 dan tutupan lamun sebesar 51,78%. Nilai rata-rata estimasi simpanan karbon lamun Enhalus acoroides di Stasiun 1sebesar 119.27 gC/m2 dan di Stasiun 2 sebesar 91.57 gC/m2. ABSTRACT: Climate change is caused by various human activities that produce carbon dioxide gas into the earth atmosphere which will have an impact on global warming. Seagrass ecosystem is able to absorb and store large number of carbon from the atmosphere that can reduce carbon emissions. This research were to determine the density, seagrass cover, biomass and carbon storage in seagrasses at Gelaman Beach (Station 1) and Alang-Alang Beach (Station 2). Survey and sampling. Were conducted using quadrant transect referring to LIPI method. Observation of the density value, the percentage of seagrass coverage was conducted in all points, while the sampling was conducted at the point 50 m on each substation by sampling method. Carbon measurement in seagrass sample used LOI method. Total seagrass density in Station 1 was 1235 ind/m2 and the total value of seagrass percentage cover was 68,76%. Total seagrass density in Station 2 was 1135 ind/m2 and total value of seagrass percentage cover was 51,78%. Average value for carbon savings estimated seagrass Enhalus acoroides in Station 1 was 119.27 gC/m2 and Station 2 was 91.57 gC/m2.

Seagrass surveys in Shwe Thaung Yan coastal areas, the southern part of Rakhine Coastal Region, Myanmar: biodiversity, coverage and biomass

Studies on percent cover and biomass of seagrasses from Shwe Thaung Yan coastal areas (Inn Din Gyi, Kyauk Nagar and Phoe Htaung Gyaing), the Southern parts of Rakhine Coastal Region, were carried out between March and August, 2018. A total of 8 species of seagrasses, namely Syringodiumisoetifolium (Ascherson) Danty, Halodulepinifolia (Miki) den Hartog, Haloduleuninervis (Forsskal) Ascherson, Cymodocearotundata Ehrenberg et Hemprich ex Ascherson, C. serrulata (R. Brown) Ascherson et Magnus, Thalassiahemprichii(Ehrenberg) Ascherson, Halophila major (Zoll.) Miquel and Enhalusacoroides (Linnaeus f.) Royle, were recorded in three study sites. Seagrass meadow in this study showed seasonal variations in both percent cover and biomass. Total seagrass coverage and biomass were higher in the dry season than in the monsoon season. Total seagrass coverage ranged between 8% and 75% in Phoe Htaung Gyaing, between 10% and 42% in Kyauk Nagar, and between 15% and 43% in Inn Din Gyi. Total seagrass mean biomass was 50.2413-259.846gdry.wtm-2 in Phoe Htaung Gyaing, 63.0194 -321.535gdry.wtm-2 in Kyauk Nagar, and 98.6819-416.237gdry.wtm-2 in Inn Din Gyi.

DISTRIBUSI DAN KONDISI KOMUNITAS LAMUN DI BANGKA SELATAN, KEPULAUAN BANGKA BELITUNG

ABSTRAKBangka Selatan memiliki potensi keanekaragaman lamun yang tinggi, tetapi informasi yang berkaitan dengan sebaran spesies dan kondisi komunitas lamun masih belum banyak diketahui. Tujuan penelitian yaitu menentukan jumlah spesies, sebaran dan kondisi komunitas lamun di Bangka Selatan. Penelitian dilaksanakan pada bulan Juni 2016 sampai Mei 2017. Lokasi penelitian dilakukan di beberapa wilayah Bangka Selatan, Kepulauan Bangka Belitung. Sebaran dan jumlah spesies lamun ditentukan berdasarkan gabungan data primer dan data sekunder. Pengambilan data kondisi padang lamun meliputi data tutupan dan kerapatan lamun dilakukan menggunakan transek kuadrat berukuran 50 cm x 50 cm. Hasil penelitian di Bangka Selatan ditemukan sebanyak 10 spesies lamun. Sebaran lamun meliputi Pantai Tanjung Kerasak (9 spesies), Pulau Lepar (8 spesies), Pesisir Desa Tukak (8 spesies), Pulau Anak Air (5 spesies), Pantai Puding dan Pulau Kelapan ditemukan hanya 4 spesies. Kondisi padang lamun di Bangka Selatan dengan kerapatan yaitu 633,37 tegakan/m2sampai 1066,76 tegakan/m2. Rata-rata persentase tutupan lamun yaitu 29,61% dikategorikan miskin.ABSTRACTSouth Bangka has a high potential for seagrass diversity, but information relating to the distribution of species and the condition of seagrass communities is still not widely understood. The research objective was to determine the number of species, distribution and conditions of seagrass communities in South Bangka. The research was conducted in June 2016 until May 2017. The location of the research was carried out in several areas of South Bangka, Bangka Belitung Islands. The distribution and number of seagrass species was determined based on a combination of primary data and secondary data. Data collection of seagrass condition includes seagrass coverage and density carried out using quadratic transect measuring 50 cm x 50 cm. The results of research in South Bangka found 10 species of seagrass. Seagrass distribution includes Tanjung Kerasak Beach (9 species), Lepar Island (8 species), Coastal Tukak Village (8 species), Anak Air Island (5 species), Puding Beach and Kelapan Island found only 4 species. Seagrass conditions in South Bangka with a density of 633.37 stands/m2 to 1066.76 stands/m2. The average percentage of seagrass cover is 29.61% which is categorized as poor.

The thin(ning) green line? Investigating changes in Kenya's seagrass coverage

Knowledge of seagrass distribution is limited to a few well-studied sites and poor where resources are scant (e.g. Africa), hence global estimates of seagrass carbon storage are inaccurate. Here, we analysed freely available Sentinel-2 and Landsat imagery to quantify contemporary coverage and change in seagrass between 1986 and 2016 on Kenya's coast. Using field surveys and independent estimates of historical seagrass, we estimate total cover of Kenya's seagrass to be 317.1 ± 27.2 km 2 , following losses of 0.85% yr −1 since 1986. Losses increased from 0.29% yr −1 in 2000 to 1.59% yr −1 in 2016, releasing up to 2.17 Tg carbon since 1986. Anecdotal evidence suggests fishing pressure is an important cause of loss and is likely to intensify in the near future. If these results are representative for Africa, global estimates of seagrass extent and loss need reconsidering.

Kondisi dan Keanekaragaman Jenis Lamun di Perairan Pulau Serangan, Provinsi Bali

Serangan Island is one of the tourism destinations in Bali which is administratively belong to the municipality of Denpasar. Tourism development near with the segrass habitat cause the segrass ecosystem being degraded in the waters of Serangan Island. This study was aimed to determine the diversity and conditions of seagrass species which were observed from the density and percentage of seagrass coverage and to examine the effect of water quality on the percentage of seagrass coverage. This research was conducted from February to March 2017 on Serangan Island using quantitative descriptive method. Sampling was conducted at three stations by taking data and samples of seagrass, measuring water quality (temperature, salinity, pH, turbidity, substrate observation) and analyze of nitrates and phosphates content. Seven types of seagrass species were found i.e. Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, Halophila ovalis, Halodule pinifolia, Syringodium isoetifolium, and Thalassodendron ciliatum. The study showed that the diversity index value was in the medium category. The density of seagrass was classified as very tight (condition scale of 5). The highest density was found on Cymodocea rotundata spesies at station I about 777 ind/m2. The highest percentage of seagrass coverage (79,55%) was found in station I which classified as good condition, while station II and station III were classified as damaged condition with value 13.65% and 20,79% respectively. Finally, the water quality parameters have relatively low effect to seagrass coverage percentage.