EVALUASI KUALITAS AIR SEBELUM DAN SESUDAH MEMASUKI WADUK JATIGEDE, SUMEDANG

Abstract

Sungai Cimanuk sebagai sungai utama bagi Waduk Jatigede perlu di monitor dan dievaluasi. Monitoring dan evaluasi tersebut merupakan faktor penting dalam pengelolaan kualitas air. Penelitian bertujuan untuk mengetahui jenis fitoplankton, kandungan nitrat, fosfat, klorofil-a sebelum dan sesudah memasuki Waduk Jatigede. Lokasi pengamatan pertama terdiri dari 3 stasiun di Sungai Cimanuk sebelum memasuki waduk, lokasi pengamatan kedua terdiri dari 3 stasiun di dalam area rencana penggenangan. Metode yang digunakan dalam penelitian yaitu metode survey sedangkan metode dalam pengambilan sample yaitu metode purposive sampling. Fitoplankton yang ditemukan  sebanyak 23 genus. Genus yang mendominasi adalah Oscillatoria, Tabellaria, Thallasionema dan Nitzschia. Kandungan nitrat sebelum memasuki waduk yaitu 2,23 - 4,19 mg/L tergolong kategori sedang (mesotrofik) dan sesudah memasuki area rencana genangan waduk berkisar 1,46 - 2,78 mg/L tergolong kategori sedang (mesotrofik). Kandungan fosfat sebelum memasuki waduk yaitu 1,305 - 4,94 mg/L tergolong kategori tinggi (eutrofik), sesudah memasuki area rencana penggenangan waduk berkisar 0,665 - 1,535 mg/L tergolong kategori tinggi (eutrofik). Kandungan klorofil-a sebelum memasuki Waduk Jatigede adalah 0,845 - 3,127 µg/L tergolong kategori sedang (meso-oligotrofik), sesudah memasuki area rencana penggenangan waduk berkisar 0,462 - 1,151 µg/L tergolong kategori rendah (oligotrofik).

Cimanuk River is a major river that flows into the area of Jatigede reservoir, that need to be monitored and evaluated. Monitoring and evaluation is an important factor in the management of water quality. The purpose of research is determine the composition of phytoplankton, the concentration of nitrate, phosphate, chlorophyll-a before and after entering the Jatigede Reservoir. The first location is in river stream before it enters the reservoir area which consists of 3 observation stations .The second is in after entering the reservoir inundation area plan  which consists of 3 location observation. The method used in the research is a survey method and the method of sampling is purposive sampling. Phytoplanktons are found as many as 23 genera. Genera which dominate are Oscillatoria, Tabellaria, Thallasionema and Nitzschia. Concentration of nitrate before entering the reservoir is 2,23 – 4,19 µg/L were classified as mesotrofik  and after entering the reservoir inundation area plan ranged from 0,46 - 2,78 µg/L were classified as mesotrofik. Concentration of phosphate before entering the reservoir ranged from 1.305 – 4,94 µg/L were classified as eutrofik, after entering the reservoir inundation plans area of Jatigede reservoir ranged from 0,665 – 1,535 µg/ L were classified as eutrofik. Concentration of chlorophyll-a before entering Jatigede Reservoir ranged from 0,845 – 3,125 µg/L were classified as meso-oligotrofik , after entering the reservoir inundation plans area of Jatigede reservoir ranged from 0,462 -1,528 µg/L were classified as oligotrofik.