PRODUKTIVITAS PRIMER PERAIRAN BERDASARKAN KANDUNGAN KLOROFIL-a DAN KELIMPAHAN FITOPLANKTON DI MUARA SUNGAI BEDONO DEMAK
Authors: Febbrianna Vida , Muskananfola Max Rudolf , Suryanti Suryanti 
Published: September 2020

ABSTRAK Muara Sungai Bedono merupakan salah satu kawasan bermangrove yang terdapat di wilayah Pantai Utara Jawa Tengah. Wilayah ini telah mengalami proses degradasi berat oleh activitas gelombang dan kegiatan antropogenik yang berpengaruh terhadap erosi, akresi dan kesuburan perairan. Hal ini akan menggangu fungsi muara sungai sebagai habitat ikan mencari makan (feeding grounds), daerah pemijahan (spawing grounds) dan daerah pengasuhan (nursery grounds). Tujuan dari penelitian ini adalah untuk mengetahui kesuburan perairan berdasarkan nilai produktivitas primer, kandungan klorofil-a dan kelimpahan fitoplankton. Penelitian dilaksanakan pada bulan Maret 2017 di Muara Sungai Bedono Kabupaten Demak. Metode yang digunakan adalah deskriptif. Lokasi sampling ditentukan tiga stasiun yaitu laut, muara bagian bawah dan tengah dengan 3 (tiga) kali pengulangan tiap stasiun pada kondisi pasang dan surut. Hasil penelitian menunjukan bahwa nilai produktivitas primer di Muara Sungai Bedono berkisar antara 425-1.650 mgC/m3/hari. Kandungan klorofil-a berkisar antara 0,07-0,45 mg/L dan kelimpahan fitoplankton berkisar antara 2.144-5.478 ind/l. Kesuburan perairan di Muara Sungai Bedono dikategorikan perairan Eutrofik ditinjau dari nilai produktivitas primer, Oligotrofik ditinjau dari kandungan klorofil-a dan Mesotrofik ditinjau dari nilai kelimpahan fitoplankton. Berdasarkan uraian tersebut kunci utama kesuburan perairan adalah produktivitas primer sehingga Muara Sungai Bedono dikategorikan perairan Eutrofik. Kata kunci: Produktivitas Primer; Kandungan Klorofil-a; Kelimpahan Fitoplankton; Muara Sungai Bedono, Demak ABSTRACT Bedono Estuary, which is located in Northern coast of central Java, is one of the coastal region inhabited with mangroves. This area has experienced heavy degradation process due to waves actions and antrophogenic activities that can affect erosion, accretion and costal water production. This will disturb the functions of estuary as fish habitat as well as feeding grounds, spawing grounds and nursery grounds. The purpose of this research to determine the fertility of waters based on the value of primary productivity, the content of chlorophyll-a and the abundance of phytoplankton. This research was conducted in March 2017 in the Bedono Demak Estuary. A descriptive method is applied in the analysis. Three stations are chosen as sampling locations: that are at the sea, lower and middle area of the estuary with three repetitions during high and low tides. The analysis results show that the value of primary productivity at the Bedono Demak Estuary ranges from 425 to 1.650 mgC/m3/day, chlorophyll-a content ranges from 0,07 to 0,45 mg/L, phytoplankton abundance ranges from 2.144 to 5.478 ind/L. Fertility waters at the Bedono Demak Estuary can be categorized as eutrophic based on the value of primary productivity, as oligotrophic based on chlorophyll-a content and Mesotrophic based on phytoplankton abundance. The results show that primary productivity is the key of fertility waters so that Bedono Demak Estuary can be categorized as eutrophic. Keywords: Primary Productivity; Chlorophyll-a; Phytoplankton Abundance; Bedono Demak Estuary.