Karakteristik Morfometrik Lamun Enhalus acoroides dan Thalassia hemprichii di Pesisir Pulau Bintan

ABSTRAK: Lamun merupakan satu-satunya tumbuhan berbiji (angiospermae) yang mampu hidup terendam di dalam air laut dan beradaptasi pada lingkungan dengan salinitas tinggi serta memiliki rhizome, daun dan akar sejati. Kajian terkait karakteristik morfometrik menekankan pada keadaan karakter morfologi suatau spesies yang mendiami suatu wilayah tertentu. Penelitian ini dilakukan dengan tujuan untuk membandingkan karakteristik morfometrik lamun Enhalus acoroides dan Thalassia hemprichii pada ekosistem lamun di beberapa wilayah pesisir di Pulau Bintan. Penentuan lokasi penelitian ditentukan dengan metode purposive sampling sedangkan pengambilan data lamun menggunakan transek kuadran ukuran 50x50cm. Karakteristik bagian lamun yang diukur yaitu panjang daun, lebar daun, diameter rhizome, panjang akar dan jumlah daun. Karakteristik morfometrik lamun di ketiga lokasi memiliki perbedaan. Lamun E. acoroides di lokasi Pantai Impian memiliki panjang daun yang terpanjang dan diameter rhizome yang paling besar dari lokasi lainnya. Sedangkan lokasi pengudang memiliki lebar daun tertinggi. Morfometrik Lamun jenis T. hemprichii yang mempunyai nilai panjang daun, lebar daun dan diameter rhizome tertinggi terdapat di lokasi Pantai Impian. Sedangkan panjang daun terendah terdapat di Pengudang. ABSTRACT: Seagrass is the only seed plant (angiosperms) that can live submerged in seawater and adapt to environments with high salinity and has rhizomes, leaves, and tree roots. Studies related to morphometric characteristics emphasize the morphological character of a species that inhabits a particular area. This research was conducted in October 2019 to March 2020 in Dompak, Pengudang Village, and Pantai Impian to compare the morphometric characteristics of the seagrass Enhalus acoroides and Thalassia hemprichii in seagrass ecosystems in some coastal areas of Bintan Island. The determination of the location of the study was determined by a purposive sampling method while seagrass data collection using a 50x50cm quadrant transect size. Morphometric characteristics of seagrasses in the three locations have differences. Seagrass E. acoroides at the Impian Beach location has the longest leaf length and the largest rhizome diameter than other locations. Whereas the storage location has the highest leaf width. Morphometrics of seagrass T. hemprichii which has the highest value of leaf length, leaf width, and rhizome diameter is at the Dream Beach location. While the lowest leaf length is found in Pengudang.

Morphometric characteristics of two seagrass species (Enhalus acoroides and Cymodocea rotundata) in four small islands in North Maluku, Indonesia

Authors. 2018. Morphometric characteristics of two seagrass species (Enhalus acoroides and Cymodocea rotundata) in four small islands in North Maluku, Indonesia. Biodiversitas 19: 2035-2043. Seagrass has an important ecological role as a protector of coastlines and small islands. It is known to be capable of forming phenotypic plasticity through morphometric variation as a response to its environmental conditions. This study aimed to determine the distribution and morphological differences between populations of two important seagrass species (Enhalus acoroides and Cymodocea rotundata) in the waters around four small islands in North Maluku. The study was conducted at two stations in each of Ternate Island and Maitara Islands, three stations at Tidore Island and one station at Hiri Island. A line transect method was used to collect seagrass samples. Morphometric characteristics included leaf sheath length, leaf length, leaf width, rhizome diameter, root length, root diameter, and internode length were measured. Discriminant analysis was performed to describe morphometric characteristics distinctive of the four islands. Leaf sheath length, leaf length, rhizome diameter, and root length of E. Acoroides differed significantly among the populations from the various islands except for leaf width. Meanwhile, leaf sheath length, leaf width, rhizome diameter, root length, and internode length differed significantly in C. rotundata among the populations from different islands except for leaf length.