Studi Persebaran Kandungan Fosfat dan Material Padatan Tersuspensi di Perairan Muara Sungai Slamaran, Kota Pekalongan

Abstract

Kota Pekalongan dilalui oleh sungai Slamaran yang menjadi tempat masuknya fosfat dari darat ke laut. Fosfat adalah nutrient yang terkandung dalam bahan organik dari limbah domestik maupun pertambakan yang mempengaruhi kesuburan perairan muara Sungai Slamaran. Konsentrasi fosfat di perairan dapat dipengaruhi oleh material padatan tersuspensi (MPT). Penelitian ini bertujuan mengkaji persebaran konsentrasi fosfat dan MPT serta mengkaji hubungan antara sebaran fosfat dan MPT di muara sungai Slamaran, kota Pekalongan. Data lapangan diambil secara in situ. Sampel air dianalisis di laboratorium. Analisis fosfat menggunakan metode yang digunakan oleh Strickland dan Parson (1968). Analisis MPT menggunakan metode gravimetri. Peta sebaran konsentrasi fosfat dan MPT dibuat dengan software ArcGis. Arus permukaan laut dimodelkan dengan software Mike 21 selanjutnya divalidasi dengan nilai RMSE dan MAE. Analisis korelasi Pearson digunakan untuk menentukan korelasi antara konsentrasi fosfat dan MPT. Hasil penelitian menunjukkan bahwa nilai konsentrasi fosfat memiliki rentang 0.44–1,84 µM, dan konsentrasi MPT memiliki rentang 56-152 mg/L. Berdasarkan peta persebaran fosfat dan MPT di perairan muara Sungai Slamaran, diduga bahwa persebaran fosfat dan MPT mendapat pengaruh dari masukan sungai dan tambak udang yang berada di muara sungai Slamaran. Hasil analisis korelasi menunjukkan korelasi yang tidak cukup kuat antara sebaran konsentrasi fosfat dengan sebaran MPT. Pekalongan city is crossed Slamaran River which is entry point phosphate from the land to the sea. Phosphate is a nutrient contained in organic material from domestic waste and aquaculture which affects the productivity of the waters of Slamaran river estuary. Phosphate concentrations in waters can be influenced by suspended solids (TSS). The aims of this study were to determine concentration of phosphate and TSS distribution and to examine correlation between phosphate and TSS concentrations in Slamaran River estuary. In situ data were taken at Slamaran River estuary. Water samples were analyzed at laboratory. Phosphate concentration analysis used method by Strickland and Parson (1968). TSS concentration analysis used gravimetric method. Distribution of Phosphate and TSS concentration were mapped using ArcGIS software. Ocean surface currents was numerically modeled used Mike 21 software then validated with RMSE and MAE methods. Pearson correlation method was used to analyzed correlation between phosphate and TSS concentration. The results showed that phosphate concentration were ranged from 0.44–1,84 µM mg/L and TSS concentration were ranged from 56-152 mg/L. Based on distribution map of phosphate and TSS in the Slamaran River estuary, it was predicted that phosphate and TSS distribution influenced by inputs from the river and shrimp ponds along the estuary Slamaran river. Results of the correlation analysis showed that correlation between phosphate and TSS concentrations distribution was not strong enough.