Formulasi Residu Garam Sargassum sp. dan Jeroan Ikan Tuna sebagai Kandidat Pupuk Slow Release
Abstract
Residu garam rumput laut Sargassum sp. dan jeroan ikan tuna merupakan limbah dari industri perairan yang dapat diolah kembali menjadi pupuk slow release karena mengandung N, P, dan K yang bermanfaat bagi tanaman. Penelitian ini bertujuan untuk menentukan rasio pupuk slow release terbaik berdasarkan unsur hara dengan tiga rasio residu garam rumput laut terhadap pupuk organik cair jeroan ikan tuna yaitu 1:5 (A1), 1:8 (A2), dan 1:10 (A3). Pengulangan dilakukan sebanyak tiga kali. Rasio tersebut memengaruhi unsur hara pupuk slow release. Rasio terbaik adalah formula A2 dengan kandungan C-organik 40,51%, N-total 3,45%, P2O5 0,78%, K2O 3,22%, pH 6,03; dan kadar air 8,63%. Analisis lanjutan menunjukkan bahwa nitrogen hanya terlepas sebanyak 24% dari pupuk pada hari ke delapan dan analisis SEM-EDS menunjukkan permukaan pupuk slow release masih memiliki permukaan agak kasar dengan beberapa pori dan mengandung lebih banyak unsur karbon. Seaweed salt residue of Sargassum sp. and tuna innards are waste from the marine industry that can be reprocessed into slow release fertilizer because they contain N, P, and K which are beneficial for plants. This research aimed to determine the best slow release fertilizer ratio based on nutrient content with three ratios of seaweed salt residue towards liquid organic fertilizer of tuna innards, the ratio was 1:5 (A1), 1:8 (A2), and 1:10 (A3). Repetition was carried out three times. The ratio affects the nutrients of slow-release fertilizer. The best ratio was formula A2 with the content of C-organic 40.51%, N-total 3.45%, P2O5 0.78%, K2O 3.22%, pH 6.03, and water content 8.63%. Further analysis showed that only 24% of nitrogen was released from the fertilizer on the eighth day and SEM-EDS analysis showed that the surface of the slow release fertilizer still had a slightly rough surface with several pores and contained more carbon elements.