KOMUNITAS IKAN DI TERUMBU KARANG PERAIRAN BATUATAS, BUTON, SULTRA
NURHAM, S.Pd., Dr. Suwarno Hadisusanto
2012 | Tesis | S2 BiologiPulau Batuatas dikelilingi oleh terumbu karang yang sangat perludilestarikan untuk habitat ikan. Tingginya kemelimpahan ikan didukung oleh penutupan karang yang baik. Kondisi fisikokimia perairan dapat memacu meningkatnya distribusi plankton kemudian diikuti meningkatnya populasi ikan dan karang. Penelitian ini bertujuan untuk mengetahui komunitas ikan karang, persentase penutupan karang, dan kondisi fisikokimia di perairan Batuatas. Penelitian dilaksanakan di zona tertutup dan zona terbuka masing-masing sebanyak 4 stasiun. Metode penelitian karang menggunakan transek garis (line intercept transect) sepanjang 30 meter 3 kali ulangan dan diikuti sensus visual ikan dengan jarak pandang 2,5 meter kekiri dan kekanan. Transek diletakkan sejajar garis pantai pada jeluk 3 meter di zona tertutup dan 5 meter di zona terbuka. Kondisi fisikokimia perairan meliputi: suhu, kecepatan arus, kecerahan air, salinitas, CaCO3, nitrat, dan fosfat setiap stasiun. Hasil penelitian menunjukkan keanekaraganan ikan di zona tertutup lebih rendah dari pada di zona terbuka. Pada zona tertutup ditemukan 88 spesies dan terdiri dari 13 spesies ikan indikator, 41 spesies ikan mayor, dan 34 spesies ikan target. Pada zona terbuka ditemukan 94 spesies dan terdiri dari 14 spesies ikan indikator, 41 spesies ikan mayor, dan 40 spesies ikan target. Apabila terjadi penurunans uhu, fosfat, dan CaCO3 akan menurunkan keragaman ikan, sedangkan peningkatan kecepatan arus dan CaCO3 akan meningkatkan laju pertumbuhan karang di zona tertutup. Peningkatan kecepatan arus dan salinitas akan meningkatkan keragamanikan, sedangkan penurunan fosfat akan menurunkan keragaman ikan pada zona terbuka. Peningkatan CaCO3 akan meningkatkan laju pertumbuhan karang, sedangkan penurunan suhu akan mematikan karang di zona terbuka. Keanekaragaman karang di zona tertutup lebih rendah daripada di zona terbuka. Pada zona tertutup ditemukan 5 spesies Acropora dan 24 spesies NonAcropora, sedangkan pada zona terbuka dijumpai 2 spesies Acropora dan 21 spesies Non Acropora. Persentase penutupan karang di zona tertutup (30,2%) lebih tinggi daripada di zona terbuka (25,20%). Dari penelitian ini dapat disimpulkan bahwa kondisi fisikokimia air laut mendukung kehidupan ikan dan pertumbuhan karang, baik yang terdapat di zona tertutup maupun di zona terbuka.
Batuatas island surrounded by coral reefs need to be preserved for fish habitat. The high abundance of fish supported by good coral cover. Physicochemical conditions of water can increased stimulate the distribution of plankton and then followed increasing the population of fish and corals. This study aims to determine reef fish communities, the percentage of coral cover, and the physicochemical conditions in the Batuatas waters. The experiment was conducted in a closed zone and open zone of each of 4 stations. Reef research method using a linetransect (line intercept transect) along 30 meters of 3 replications and followed visual census the fish with 2.5 meter visibility and left to right. Transects placed parallel to the coastline at 3 meter container in a closed zone and 5 yards in the open zone. Aquatic physicochemical conditions include: temperature, flow velocity, the brightness of the water, salinity, CaCO3, nitrate, and phosphate each station. The results showed diversity fish in the closed zone is lower than in the open zone. In the closed zone found 88 species and 13 species of fish consists of an indicator, 41 major species of fish and 34 species of fish targeted. In the open zone found 94 species and 14 species of fish consists of indicators, 41 major species of fish and 40 species of fish targeted. When the temperature decreases, phosphate, and CaCO3 will reduce the diversity of fish, while the increase in flow velocity and CaCO3 would increase the rate of coral growth in a closed zone. Increased flow rate and salinity will increase the diversity of fish, while the decrease in phosphate will decrease the diversity of fish in the open zone. CaCO3 would increase the rate of increase in coral growth, while decreasing the temperature will kill the coral in the open zone. Coral diversity in the closed zone is lower than in the open zone. In the closed zone is found 5 species of Acropora and 24 species of non-Acropora, whereas in the open zone encountered two Acropora species and 21 species of non-Acropora. The percentage of coral cover in the closed zone (30.2%) higher than in the open zone (25.20%). From this study it can be concluded that the physicochemical conditions of sea water to support fish life and coral growth, both contained in a closed zone and in the open zone.
Kata Kunci : Komunitas ikan, karang, Batuatas, dan fisikokimia perairan.
