Keanekaragaman dan Kelimpahan Ikan Serta Keterkaitannya dengan Kualitas Perairan di Danau Toba Balige Sumatera Utara

Abstract

The diversity and overflowing of fish in the Balige Toba Lake Waterway and the relation with the quality of water in Lake Toba, has been analyzed in December 2008 ñ February 2009. In order to determine sample location is using ìPurpose Random Samplingî and sample taken by using net. Sample identification held in the center of Environment Effect Research (PUSLITDAL) and in The Laboratory of PSDAL FMIPA USU. The result of this research showed physical, chemical and biology nature in Balige Toba Lake Waterway (temperature, BOD, COD, DO, phosphate, Coliform) still in appropriate limitation for fishes, meanwhile based on PP No. 82 year 2001 and Storet Method. Balige Toba Lake Waterway including low and middle pollutant. Based on biological parameter colifecal Balige Toba Lake Waterway tend to low pollutant. In Balige Toba Lake Waterway have been found I class of fish such as Osteicthyes with 3 ordo such as Cypriniformes, Perciformes, Ostariophysii and 5 family such as Cyprinidae, Chichilidae, Eleotridae,Claridae, Cebitidae also 7 genus and 7 species including Cyprinus Carpio, Mystacoleucus padangensis, Tilapia mossambica, Oreochromis sp, Opheocephalus striatus, Oxyeleotris marmorata and Clarias batracus. The highest fishes density come from Pora-pora fish (Mystacoleucus padangensis) with grade 0,116 perm2, whereas the lowest is Gabus fish (Opheocephalus striatus) with grade 0,005 perm2. Fish type with the highest presentation is Pora-pora fish (Mystacoleucus padangensis) for about 100% meanwhile the lowest is for about 33,33%. The diversity index of fish in the four research stations are between 1,12 ñ 1,37 with diversity index 0,63 ñ 0,70. Similarity index among four stations are about 83,33%-100%. The result of Pearson correlation test showed that temperature, BOD5 nitrate, PO4, and Coliform correlated or same course with unreal effect toward. Diversity and the over flowing of fish in Balige Toba Lake Waterway, DO, pH, saturation and COD, not correlated or contrary with unreal effect toward diversity and the amount

of fish in Balige Toba Lake Waterway.

Keanekaragaman dan kelimpahan ikan di Perairan Danau Toba Balige serta keterkaitannya dengan kualitas Perairan di Danau Toba Balige, telah diteliti pada bulan Desember 2008 ñ Februari 2009. Metode yang digunakan dalam menentukan lokasi pengambilan sampel adalah ìPurpose Random Samplingî dan sampel diambil dengan menggunakan jaring. Identifikasi sampel dilakukan di Puslitdal dan di Laboratorium PSDAL FMIPA USU. Hasil penelitian menunjukkan sifat fisika kimia dan biologi Perairan Danau Toba Balige (Temperatur, pH, BOD, COD, DO dan Coliform, masih berada dalam batas yang layak bagi kehidupan ikan kecuali NO3 dan pHs, sedangkan berdasarkan PP No. 82 Tahun 2001 dan Metode Storet. Perairan Danau Toba Balige tergolong tercemar ringan dan sedang. Berdasarkan parameter biologis Colifecal Perairan Danau Toba Balige tergolong tercemar ringan. Di Perairan Danau Toba Balige ditemukan 1 kelas ikan yaitu kelas Osteicthyes dengan 3 ordo antara lain Cypriniformes, Perciformes, Ostariophysii dan 5 family yaitu Cyprinidae, Chichilidae, Eleotridae, Claridae, Cebitidae serta 7 genus dan 7 spesies yang meliputi Cyprinus Carpio, Mystacoleucus padangensis, Tilapia mossambica, Oreochromis sp, Opheocephalus striatus, Oxyeleotris marmorata dan Clarias batracus. Kepadatan ikan tertinggi dari jenis ikan Pora-pora (Mystacoleucus padangensis) 0,116 per m2 sedangkan yang terendah adalah ikan Gabus (Opheocephalus striatus) dengan nilai 0,003 per m2. Jenis ikan dengan frekuensi kehadiran tertinggi ikan Pora-pora (Mystacoleucus padangensis) sebesar 100% sedangkan terendah adalah Oreochromis sp, sebesar 33,33%. Indeks keanekaragaman ikan pada keempat stasiun penelitian berkisar antara 1,12 ñ 1,37 dengan keseragaman 0,63 ñ 0,70. Indeks similaritas antara keempat stasiun berkisar antara 83,33% ñ 100%. Hasil uji korelasi Pearson menunjukkan bahwa temperatur, BOD5,, Nitrat, Fosfat dan Coliform berkorelasi searah terhadap keanekaragaman dan kelimpahan ikan Perairan Danau Toba Balige, DO, pH, COD dan kejenuhan, berkorelasi berlawanan arah terhadap keanekaragaman dan kelimpahan ikan di Perairan Danau Toba Balige.