Keterkaitan Keberadaan Fosfor dalam Sedimen dan Air di Waduk Jatigede, Sumedang, Jawa Barat

Abstract

Keberadaan fosfor berupa materi yang mengendap pada sedimen dan materi terlarut pada kolom air. Namun faktor yang mempengaruhi keberadaan fosfor sedimen dan air pada dasar perairan belum dapat dipahami dengan baik penyebabnya. Penelitian ini bertujuan menganalisis faktor yang mempengaruhi sebaran fosfor dalam sedimen dan air di Waduk Jatigede. Pengambilan contoh dilakukan pada bulan Febuari, Maret, dan April 2021 di enam stasiun pengamatan. Analisis data terdiri dari uji signifikansi kesamaan antarwaktu, penentuan musim, pengelompokan stasiun, sebaran fosfor sedimen dan air, keterkaitan fosfor sedimen dan air dengan parameter fisika-kimia sedimen dan kualitas air, serta pendugaan pertukaran fosfor antar sedimen dan air. Berdasarkan curah hujan BMKG kondisi musim Waduk Jatigede yaitu musim hujan. Waduk Jatigede terdiri dari Zona Riverin, Zona Transisi, dan Zona Lakustrin. Konsentrasi fosfor sedimen dan air lapisan hipolimnion tertinggi pada Zona Lakustrin. Sebaran fosfor sedimen dan air menunjukan adanya keterkaitan. Faktor yang mempengaruhi keterkaitan tersebut adalah parameter fisika-kimia sedimen (debu, liat, P-tersedia, pH sedimen, dan DO) dan kualitas air (suhu, kekeruhan, TSS, ortofosfat, DO, pH, dan alkalinitas).

The presence of phosphorus in the form of material that settles in the sediment and dissolved material in the water column. However, the factors that affect the presence of phosphorus in sediments and water at the bottom of the water are not well understood. This study aims to analyze the factors that influence the distribution of phosphorus in sediment and water in the Jatigede Reservoir. Sampling was carried out in February, March, and April 2021 on six observation stations. Data analysis consists of testing the the similarity between times, determining the season, grouping stations, distribution of phosphorus in sediment and water, the relationships between phosphorus in sediment and water with the physico-chemical parameters of sediment and water quality, as well as estimation of the exchange of phosphorus between sediment and water. Based on rainfall intensity, the study period in the Jatigede Reservoir occured in the rainy season. Jatigede Reservoir consists of Riverine Zone, Transition Zone, and Lacustrine Zone. Results showed the highest concentration of phosphorus in sediment and water in the hypolimnion layer was in the Lacustrine Zone. There were strong relationships between phosphorus in sediment and water. The most influencing factors of these relationships were physico-chemical parameters of sediment (i.e. dust, clay, available P, sediment pH, and DO) and water quality (i.e. temperature, turbidity, TSS, orthophosphate, DO, pH, and alkalinity).