Studi Komunitas Padang Lamun di Kecamatan Tanggetada, Kabupaten Kolaka, Sulawesi Tenggara

Kecamatan Tanggetada memiliki areal padang lamun yang luas dan sering dimannfaatkan oleh masyarakat. Padang lamun di daerah ini belum terkonfimasi secara ilmiah baik itu dari jenis, kerapatan dan komunitas lamunnya. Penelitian ini bertujuan untuk mengetahui jenis dan kerapatan lamun di Kecamatan Tanggetada. Metode yang digunakan pada penelitian ini adalah metode transek kuadrat pada areal 100 m2 ditiap stasiun. Lokasi penelitian berada di 3 stasiun yaitu Stasiun 1 di Kelurahan Tanggetada, Stasiun 2 di Desa Palewai dan Stasiun 3 Kecamatan Anaiwoi. Hasil penelitian, ditemukan 6 jenis lamun tersebar di Kecamatan Tanggetada yaitu Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, Halodule uninervis, Halophila ovalis, dan Syringodium isoetifolium. Kerapatan lamun termasuk dalam kategori rapat dan jarang. Stsiun 1 memiliki kerapatan lamun yang tinggi dengan ketegori rapat yaitu 160.46 ind/m2, kemudian Stasiun 2 dengan kerapatan lamun agak rapat yaitu 117.49 ind/m2 dan Stasiun 3 dengan kerapatan lamun yang rendah dengan kategori jarang yaitu 60.59 ind/m2. Thalassia Hempricii merupakan lamun yang memiliki nilai kerapatan paling tinggi dibandingkan jenis lamun lainnya.

Local Victory: Assessing Interspecific Competition in Seagrass From a Trait-Based Perspective

Tropical seagrass meadows are formed by an array of seagrass species that share the same space. Species sharing the same plot are competing for resources, namely light and inorganic nutrients, which results in the capacity of some species to preempt space from others. However, the drivers behind seagrass species competition are not completely understood. In this work, we studied the competitive interactions among tropical seagrass species of Unguja Island (Zanzibar, Tanzania) using a trait-based approach. We quantified the abundance of eight seagrass species under different trophic states, and selected nine traits related to light and inorganic nutrient preemption to characterize the functional strategy of the species (leaf maximum length and width, leaves per shoot, leaf mass area, vertical rhizome length, shoots per meter of ramet, rhizome diameter, roots per meter of ramet, and root maximum length). From the seagrass abundance we calculated the probability of space preemption between pairs of seagrass species and for each individual seagrass species under the different trophic states. Species had different probabilities of space preemption, with the climax species Thalassodendron ciliatum, Enhalus acoroides, Thalassia hemprichii, and the opportunistic Cymodocea serrulata having the highest probability of preemption, while the pioneer and opportunistic species Halophila ovalis, Syringodium isoetifolium, Halodule uninervis, and Cymodocea rotundata had the lowest. Traits determining the functional strategy showed that there was a size gradient across species. For two co-occurring seagrass species, probability of preemption was the highest for the larger species, it increased as the size difference between species increased and was unaffected by the trophic state. Competitive interactions among seagrass species were asymmetrical, i.e., negative effects were not reciprocal, and the driver behind space preemption was determined by plant size. Seagrass space preemption is a consequence of resource competition, and the probability of a species to exert preemption can be calculated using a trait-based approach.

Phytochemical profiles and ethnomedicine preliminary studies on seagrass species in the Southern Coast of Lombok Island Indonesia

Seagrass is a coastal plant that is not only important in maintaining the stability of coastal ecosystems, but also provides many benefits in daily life. Seagrass has long been used as traditional medicine by coastal residents in South Lombok. The purpose of this study was to screen the main types of secondary metabolites contained in seagrass in the southern coast of Lombok Island and to obtain information about the species of seagrass used as traditional medicine for certain types of diseases in local residents. Seagrass samples were taken from the south coast and the extraction process was carried out by maceration method using 96% ethanol as solvent. The crude extract obtained was then subjected to qualitative and quantitative phytochemical tests. The phytochemical qualitative test showed that Syringodium isoetifolium, Enhalus acoroides, Halophila decipiens, Cymodocea rotundata, Thalassia hemprichii, and Cymodocea cerulata contain compounds such as flavonoids, tannins, and phenols. Quantitative phytochemical analysis showed that E. acoroides had the highest total flavonoid content (3.7 mg QE/g) compared to that of other species, while the highest total phenolic content was indicated by T. hemprichii (33 mg GAE/100 g). The results of interviews related to the ethnomedicinal aspects of seagrass indicate that four species commonly used by local residents in healing diseases are E. acoroides, S. isoetifolium, T. hemprichii, and C. cerulata. They are widely used both as an external medicine (itching-skin diseases and external wounds) and internal medicine, such as heart, cancer, and kidney disease. Based on the phytochemical profile and ethnomedicine studies, the four seagrass species can be an alternative source in obtaining bioactive compounds for the development of specific drugs in the future.

KOMUNITAS LAMUN DI PERAIRAN PANTAI DESA ORI, MALUKU TENGAH

Seagrass communities play an important role in marine environments and estuary area, supporting communities of fish, snails and shellfish and other invertebrates. The diversity of seagrass species in the world is very low (<60 species). The coastal waters of Ori Village have a seagrass community that has never been studied. The purpose of this study was to estimate the structure of the seagrass community in the coastal waters of Ori Village, Central Maluku which includes the composition of type, density, frequency of occurence and percent of coverage. Seagrass sampling uses the line transect method. Five species of seagrass were found during the study grouped into two families: Cymodoceaceae and Hydrocharitaceae. The seagrass species found were Cymodocea rotundata, Halodule pinifolia, Enhalus acoroides Halophila ovalis and Thalassia hemprichii. T. hemprichii and E. acoroides have the highest densities (157 shoots/m2 and 137 shoots/m2, respectively). E. acoroides and T. hemprichii also have the highest frequency of occurence and relative coverage percent compared to other seagrass species found in the waters of Ori Village. Seagrass community in the waters of Ori Village is classified in a tight condition until dense. ABSTRAK Komunitas lamun memegang peranan penting di lingkungan laut dan daerah estuari, menyokong komunitas ikan, siput dan kerang-kerangan serta invertebrata lainnya. Keragaman spesies lamun di dunia sangat rendah (<60 spesies). Perairan pantai Desa Ori memiliki komunitas lamun yang belum pernah diteliti. Tujuan dari penelitian ini adalah untuk mengestimasi struktur komunitas lamun di perairan pantai Desa Ori, Maluku Tengah yang meliputi komposisi jenis, kerapatan, frekuensi kehadiran dan persen penutupan. Pengambilan sampel lamun menggunakan metode transek garis. Lima spesies lamun ditemukan selama penelitian yang dikelompokan dalam dua famili yaitu famili Cymodoceaceae dan Hydrocharitaceae. Spesies-spesies lamun yang ditemukan adalah Cymodocea rotundata, Halodule pinifolia, Enhalus acoroides Halophila ovalis danThalassia hemprichii. T. hemprichii dan E. acoroides memiliki kerapatan tertinggi (masing-masing 157 tegakan/m2 dan 137 tegakan/m2). E. acoroides dan T. hemprichii juga memiliki frekuensi kehadiran serta persen penutupan relatif tertinggi dibanding spesies-spesies lamun lainnya yang ditemukan di perairan Desa Ori. Komunitas lamun di perairan Desa Ori tergolong dalam kondisi rapat sampai padat. Kata Kunci: Lamun, komunitas, kerapatan, penutupan, Maluku Tengah

MORFOMETRIK LAMUN Thalassia hemprichii BERDASARKAN TIPE SUBSTRAT DI PERAIRAN PANTAI TANJUNG TIRAM, POKA, TELUK AMBON DALAM

Seagrass as a flowering plant can live from muddy substrates to coral fractures. Differences in the characteristics of substrate type, nutrient content and aquatic environmental conditions can affect morphometric seagrass. The purpose of the study was to analyze environmental conditions and nutrient content as well as the morphometric characteristics of T. hemprichii seagrass based on differences in substrate type. This study was conducted in the waters of Tanjung Tiram Coastal, Poka from February-April 2021. Seagrass sampling was using the purposive sampling method. Data analysis was conducted using ANOVA with SPSS. The results of environmental parameters analysis showed that the water conditions of Tanjung Tiram, Poka are still at the tolerance limit intended for seagrass life. The substrate consists of sand substrate, gravel mixed sand substrate and mud substrate. The results of ANOVA showed that there was a significant difference in the content of sedimentary nutrients, especially phosphates in each substrate type and there was a significant difference in morphometric seagrass based on differences in substrate type and nutrient content. ABSTRAK Lamun sebagai tumbuhan berbunga dapat hidup mulai dari substrat berlumpur sampai dengan patahan karang. Perbedaan karakteristik jenis substrat, kandungan nutrien dan kondisi lingkungan perairan dapat mempengaruhi morfometrik lamun. Tujuan dari penelitian ini adalah menganalisis kondisi lingkungan dan kandungan nutrien serta karakteristik morfometrik lamun T. hemprichii berdasarkan perbedaan tipe substrat. Penelitian ini dilaksanakan di Perairan Pantai Tanjung Tiram, Poka pada Bulan Februari-April 2021. Pengambilan sampel lamun menggunakan metode purposive sampling. Analisis data menggunakan ANOVA dengan SPSS. Hasil analisis parameter lingkungan, menunjukan bahwa kondisi perairan Tanjung Tiram, Poka masih berada pada batas toleransi yang diperuntukan untuk kehidupan lamun. Substrat terdiri dari substrat pasir, pasir campur kerikil dan lumpur. Hasil anova menunjukan bahwa terdapat perbedaan kandungan nutrien sedimen khususnya fosfat secara signifikan pada masing masing tipe substrat dan terdapat perbedaan morfometrik lamun secara signifikan berdasarkan perbedaan tipe substrat dan kandungan nutrien. Kata Kunci: morfometrik, nutrien, substrat, Tanjung Tiram, Thalassia hemprichii

Structure of Seagrass Community in the Karapyak Beach, Pangandaran Regency, West Java

Karapyak Beach is one of the beaches that has a variety of abundant marine ecosystems. One of the marine ecosystems is seagrass. This study aims to identify the structure of seagrass communities in Karapyak waters based on seagrass species, species density, species frequency, diversity, and uniformity. This research was conducted in February – April 2021. The method used is a survey method with direct observation at each predetermined station using a square transect measuring 1 x 1 m2. While the determination of stations and observation points is done by purposive sampling method. The research location is divided into three stations, each station is divided into five substations (plots), and a 50 m transect line is made perpendicular to the shoreline. Furthermore, the results showed four types of seagrass found in the waters of Karapyak Beach, namely Cymodocea rotundata, Thalassia hemprichii, Halodule pinifolia, Halodule uninervis. The density of seagrass at station I was in the medium category, namely 125 individuals/m2, with a cover percentage of 86%. Then the lowest seagrass density was found at the second station, which was 104 individuals/m2 including the unhealthy category with a cover percentage of 58%. While the highest density score was shown at the third station, namely 144 individuals/m2 with a closing percentage of 94%.

POTENSI SIMPANAN KARBON PADANG LAMUN DI PANTAI POKEMON, KARIMUNJAWA

Peningkatan emisi Gas Rumah Kaca (GRK) terutama karbondioksida (CO2) menyebabkan pemanasan global. Oleh karena itu diperlukan mitigasi emisi CO2 dengan memanfaatkan potensi lamun sebagai penyimpan karbon dalam bentuk biomassa. Tujuan penelitian ini untuk mengetahui kemampuan lamun jaringan atas dan jaringan bawah dalam menyimpan karbon di perairan Pantai Pokemon pada Agustus 2020. Metode penelitian yang digunakan yaitu metode survei dan deskriptif eksploratif. Sampel diambil dari 3 stasiun pengamatan dengan line dan kuadrant transect menggunakan metode purposive sampling. Pengukuran parameter kualitas perairan dilakukan secara insitu. Analisis simpanan karbon lamun diukur menggunakan metode pengabuan atau loss on ignition (LOI). Hasil penelitian menunjukkan terdapat 4 jenis lamun yaitu Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, dan Halophila ovalis dengan jenis T. hemprichii yang mendominasi. Total kerapatan sebesar 295,62 ind/m2 dan total penutupan yaitu 21,29%. Biomassa secara keseluruhan sebesar 74,42 gbk/m2 dengan biomassa jaringan atas sebesar 35,80 gbk/m2 dan jaringan bawah sebesar 38,62 gbk/m2. Simpanan karbon sebesar 0,23 ton C/ha dengan jaringan atas sebesar 0,10 ton C/ha dan jaringan bawah 0,13 ton C/ha. Total stok karbon mencapai 1,13 ton C dalam luasan padang lamun sebesar 4,903 ha dengan stok karbon jaringan atas bernilai 0,51 ton C dan jaringan bawah sebesar 0,62 ton C. Secara umum lamun jaringan bawah di Pantai Pokemon lebih besar menyimpan karbon.