BUDIDAYA RUMPUT LAUT Sargassum sp. DENGAN METODE KANTONG PADA BEBERAPA TINGKAT KEDALAMAN DI DUA WILAYAH PERAIRAN BERBEDA

Abstract

Optimalisasi produksi rumput laut memerlukan teknologi budidaya yang tepat. Rumput laut Sargassum sp. mudah mengalami kerontokan talus. Hal inilah yang melatarbelakangi perlunya kajian penerapan metode kantong untuk budidaya rumput laut Sargassum sp. Tujuan penelitian ini adalah untuk mengetahui respons pertumbuhan rumput laut Sargassum sp. yang dibudidayakan dengan metode kantong pada beberapa tingkat kedalaman. Penelitian dilakukan di dua lokasi berbeda yakni perairan Kabupaten Pohuwato Provinsi Gorontalo dan perairan Kabupaten Bolaang Mongondow Utara Provinsi Sulawesi Utara pada bulan Maret-Mei 2016. Desain penelitian menggunakan RAL faktorial yang terdiri atas faktor wadah kantong (tanpa kantong, wadah kantong dengan ukuran mata jaring 1,5; 0,75; dan 0,25 inci) dan kedalaman (permukaan 0; 50; 100; 150; dan 200 cm) masing-masing diulang lima kali. Hasil penelitian menunjukkan bahwa faktor wadah kantong dan kedalaman, serta interaksi keduanya berpengaruh terhadap pertumbuhan rumput laut Sargassum sp. pada taraf uji 5% (P<0,05) di kedua lokasi penelitian. Pertumbuhan terbaik diperoleh dari perlakuan K0D0 (tanpa kantong dan di permukaan air) sedangkan pertumbuhan terendah terjadi pada perlakuan K3D4 (kantong meshsize 0,25 inci pada kedalaman 200 cm). Bobot tertinggi di lokasi-I mencapai 235,8 g dan terendah 19,2 g; sedangkan di lokasi-II tertinggi 208,4 g dan terendah 42,2 g. Penggunaan kantong rumput laut kurang efektif dalam memacu pertumbuhan rumput laut Sargassum sp. Pertumbuhan sangat dipengaruhi oleh intensitas cahaya, karenanya budidaya Sargassum sp. perlu memperhatikan faktor kedalaman perairan yang berkorelasi dengan intensitas cahaya matahari.

Optimization of seaweed production requires an appropriate cultivation technology. The thallus of Sargassum sp. is easy to break. This was the underlying reason to study the application of bag method in cultivating Sargassum sp. The research aimed to find out the growth response of Sargassum sp. cultivated using bag method at various depth levels. The research was conducted in two different locations, namely Pohuwato Regency Gorontalo and North Bolaang Mongondow Regency North Sulawesi from March to May 2016. The experiment was carried out using the factorial design, consisting of bag factor (without bag; mesh size bag of 1.5; 0.75; and 0.25 inches) and depth factor (surface 0; 50; 100; 150; and 200 cm) with five replications. Results of the research showed that both parameters (bag and the depth factor) and their interaction have affected the growth of Sargassum sp. at 5% confidence level (P<0.05) in both locations. The highest growth response was found in K0D0 treatment (without bag on the water surface) whereas the lowest growth was showed by K3D4 treatment (mesh size bag of 0.25 inches at 200 cm depth). The highest weight at location-I was 235.8 g and the lowest weight was 19.2 g. In location-II, the highest weight was 208.4 g and the lowest was 42.2 g. The use of bags was ineffective in boosting the growth of cultured Sargassum sp. The growth of seaweed is strongly influenced by the intensity of light. Therefore, it is recommended that the cultivation of Sargassum sp. should consider the relationship between the water depth factor and the intensity of sunlight