Kandungan Amonium, Nitrat, Fosfat, dan Plankton Pada Tambak Intensif Udang Vaname (Litopenaeus vannamei) Periode 38-66 Hari

Ghina Soraya, Dr. Ir. Bambang Triyatmo, M.P.

2019 | Skripsi | S1 AKUAKULTUR

Penelitian ini bertujuan untuk mengetahui konsentrasi amonium, nitrat, fosfat, dan plankton pada periode 38-66 hari pemeliharaan udang vaname (Litopenaeus vannamei) pada tambak intensif di Pesisir Depok, Kabupaten Bantul. Penelitian dilaksanakan pada bulan Oktober sampai November 2018. Penelitian dilakukan dengan metode pengamatan secara langsung terhadap 3 petak tambak. Petak tambak yang digunakan penelitian menggunakan plastik High Density Poly Ethylene (HDPE) dengan volume 50 x 50 x 3 m3 dan kedalaman air 1,5 m. Benih udang yang ditebar post larva (PL) 10-12, dengan kepadatan 120 ekor/petak. Lama pemeliharaan udang 78-82 hari, dengan nisbah konversi pakan 1,1. Pengamatan air tambak dilakukan setiap 7 hari selama 30 hari, pada periode pemeliharaan udang 38-66 hari. Sampel air diambil pada 3 titik yaitu dekat saluran pemasukan (inlet) air, area tengah dekat jembatan anco, dan dekat saluran keluar (outlet) air; masing-masing pada 2 kedalaman yaitu permukaan dan dasar tambak. Data hasil pengamatan dianalisis secara deskriptif dan regresi linear berganda. Hasil penelitian menunjukkan nilai kisaran (rata-rata) amonium 0,482 - 1,610 (0,821) mg/L; nitrat 0,08 - 1,298 (0,651) mg/L; dan fosfat 0,321 - 2,342 (1,085) mg/L. Plankton air tambak selama pengamatan bersifat fluktuatif dengan nilai kisaran (rata-rata) densitas fitoplankton 20.000 - 320.000 (121.667) sel/ml dan densitas zooplankton 0 - 22.500 (9.167) sel/ml; sedangkan diversitas fitoplankton 1,04 - 3,87 (2,78) dan diversitas zooplankton 0 - 2,95 (0,95). Hubungan konsentrasi amonium (X1), nitrat (X2), dan fosfat (X3) dengan densitas (Y1) dan diversitas (Y2) fitoplankton menunjukkan persamaan berikut Y1 = 235060,9 - 24806,3 X1 - 64698,2 X2 - 49314,1 X3 (R2 = 0,073) dan Y2 = 3,9 - 0,426 X1 - 0,410 X2 - 0,552 X3 (R2 = 0,332).

This research aims to determine the concentration of ammonium, nitrate, phosphate, and plankton in the period of 38-66 days of Pacific White Shrimp (Litopenaeus vannamei) culture in intensive ponds at Depok Coastal, Bantul Regency. The research was conducted from October to November 2018. The research was conducted with a method of direct observation of 3 ponds. The ponds used High Density Poly Ethylene (HDPE) plastic with a volume of 50 x 50 x 3 m3 and a water depth of 1,5 m. Shrimp seeds were stocked post larvae (PL) 10-12, with a density of 120 seeds/pond. The day of shrimp culture 78-82 days, with a feed conversion ratio of 1,1. Observation of ponds water were carried out every 7 days for 30 days, in the 38-66 days of shrimp culture. Water samples are taken at 3 points namely near the water inlet, the middle area near the Anco bridge, and near the water outlet; each at 2 depths, namely the surface and bottom of the pond. Data from the observations were analyzed descriptively and multiple linear regression. The results showed a range (average) value of ammonium 0,482 - 1,610 (0,821) mg/L; nitrate 0,08 - 1,298 (0,651) mg/L; and phosphate 0,321 - 2,342 (1,085) mg/L. The plankton of pond water during observation was fluctuating with a range (average) of phytoplankton density of 20.000 - 320.000 (121.667) cells/ml and zooplankton density of 0 - 22.500 (9.167) cells/ml; while phytoplankton diversity from 1,04 to 3,87 (2,78) and zooplankton diversity from 0 to 2,95 (0,95). The relationship of the concentration of ammonium (X1), nitrate (X2), and phosphate (X3) with density (Y1) and diversity (Y2) of phytoplankton shows the following equation Y1 = 235060,9 - 24806,3 X1 - 64698,2 X2 - 49314,1 X3 (R2 = 0,073) and Y2 = 3,9 - 0,426 X1 - 0,410 X2 - 0,552 X3 (R2 = 0,332).

Kata Kunci : amonium, fosfat, nitrat, plankton, udang vaname