Keanekaragaman Plankton yang Toleran di Perairan Kawasan Pulau Lusi Kabupaten Sidoarjo
The Diversity of Tolerant Plankton in the Coastal Waters of Lusi Island Sidoarjo Regency
Pulau Lusi ialah pulau buatan terbentuk dari hasil pengerukan endapan sedimen lumpur lapindo, akibat dari pembuangan lumpur yang kurang baik dapat menghilangkan potensi yang ada di Sungai Porong. Salah satu indikator yang dapat digunakan untuk mengetahui kualitas perairan yaitu menggunakan indeks keanekaragaman plankton. Penelitian ini bertujuan untuk mendeskripsikan keanekaragaman plankton yang toleran di perairan kawasan Pulau Lusi Kabupaten Sidoarjo dan mengetahui kualitas air di perairan kawasan Pulau Lusi Kabupaten Sidoarjo berdasarkan indeks keanekaragaman plankton. Penelitian ini dilakukan dengan metode observasi, yaitu dengan pengambilan sampel pada 5 stasiun di perairan kawasan Pulau Lusi. Pengambilan sampel plankton menggunakan plankton net, selanjutnya diamati, diidentifikasi, dihitung, dan dianalisis indeks keanekaragaman plankton. Parameter fisika kimia yang diukur meliputi suhu, kecerahan, kedalaman, kecepatan aliran arus, salinitas, kekeruhan, DO, BOD, CO2, pH. Indeks keanekaragaman plankton dianalisis menurut indeks Shannon-Weaner selanjutnya dibandingkan dengan penggolongan tingkat pencemaran perairan berdasarkan indeks keanekaragaman plankton. Berdasarkan penelitian yang dilakukan di Perairan Kawasan Pulau Lusi ditemukan fitoplankton sebanyak 10 divisi, 12 kelas, 37 famili, 42 genus, 53 spesies serta zooplankton sebanyak 5 divisi, 7 kelas, 9 famili, 9 genus, 14 spesies. Spesies fitoplankton yang dominan ialah Striatella unipunctata yang termasuk dalam kelas Bacillariophyceaea, serta spesies zooplankton yang dominan ialah Tintinnopsis hemiperalis, Nebela collaris, Notholca sp, dan Rotaria neptunia. Indeks keanekaragaman plankton di Pulau Lusi adalah 4,08 termasuk dalam kriteria sedang dan kualitas di perairan kawasan Pulau Lusi termasuk kriteria baik.
Kata kunci: keanekaragaman plankton; toleran; Pulau Lusi
Lusi Island was an artificial island formed by a result of the dredging of Lapindo mud sediment deposition, due to improper disposal of Lapindo mud can eliminate the potential of the Porong River. One indicator that can be used to determine water quality was using the diversity index of plankton. The purpose of this research was to describe the diversity of plankton that was tolerant in the waters of the Lusi Island, Sidoarjo Regency and determine the water quality in the waters of the Lusi Island, Sidoarjo Regency based on the plankton diversity index. This research was conducted by observation method, specifically by taking samples at 5 stations in the waters of the Lusi Island region. Plankton sampling was using plankton net, then was observed, identified, calculated, and analyzed the diversity index of plankton. Chemical physics parameters was measured include temperature, brightness, depth, current flow velocity, salinity, turbidity, DO, BOD, CO2, pH. The plankton diversity index was analyzed according to the Shannon-Weaner index then compared with the classification of the level of water pollution based on the plankton diversity index. Based on research conducted in the coastal waters of Lusi Island found phytoplankton consisted of 10 divisions, 12 classes, 37 families, 42 genera, 53 species, and zooplankton consisted of 5 divisions, 7 classes, 9 families, 9 genera, 14 species. The dominant phytoplankton species was Striatella unipunctata which belongs to the Bacillariophyceae class, and the dominant of zooplankton species were Tintinnopsis hemiperalis, Nebela collaris, Notholca sp, and Rotaria neptunia. The plankton diversity index on Lusi Island is 4.08 which is included in the medium criteria and quality in the coastal waters of the Lusi Island region were included in the good criteria.
Key words: plankton diversity; tolerant; Lusi Island