ANALISIS TANAH TAMBAK SEBAGAI INDIKATOR TINGKAT KESUBURAN TAMBAK - M. Hidayanto; Agus Heru W Heru W; Yossita F. (Jurnal Pengkajian dan Pengembangan Teknologi Pertanian, 2004)
The study aimed at assessing fertility condition of soil fishpond in all of study areas. The research wasconducted in Muara Badak, Samboja, Muara Pantuan and Muara Jawa Subdistricts, Kutai District. Soil samples fromtop soil (0-5 cm) and sub soil (5-50 cm) to be analyzed were taken from sites lose and far from the coast (5 km fromcoastal line). Texture, potential redox (Eh), organic-C, N, P, K, Ca and Mg were analyzed. Results of this studyindicated that: (1) Fishpond soil in Muara Badak, Muara Jawa, Muara Pantuan and Samboja (Kutai District) had highcontents of organic-C, K and Na, base saturation, and available of K2O, (2) C/N ratio and available of P2O5 , (3) TotalN was moderate, (4) Effective and potential CEC, Ca, and Mg were very low. Soil fishpond texture had 30 percent ofclay fraction, sand 42 percent, and silt 28 percent. Fishpond soil at Muara Jawa and Muara Pantuan were more fertilethan that in Muara Badak and Samboja. At all of the study sites were suitable for fishpond. However, it is necessaryto improve soil fertility in Muara Badak and Samboja for optimal fishpond productivity. CEC in all of the study siteswere low and fertilizers to improve soil of the fishponds should be properly applied because excessive application rateof fertilitizer will be leached easily.Key words: soil analysis, fertility, fishpond. Untuk mengetahui kesuburan tanah tambak telah dilakukan penelitian di Kecamatan Muara Badak, Samboja,Muara Pantauan dan Muara Jawa Kabupaten Kutai. Sampel tanah top soil(0-5cm) dan sub soil (5-50cm) diambil daridaerah dekat pantai dan jauh dari pantai (5 km ke arah darat), dan dilakukan analisis terhadap tekstur, redoks potensial(Eh), C-organik, N, P, K, Ca dan Mg. Hasil penelitian menunjukkan bahwa: (1) Tanah tambak di Muara Badak,Muara jawa, Muara Pantauan dan Samboja (Kabupaten Kutai), kandungan C-organik, K dan Na, Kejenuhan Basa(KB) dan K2O sangat tinggi, (2) C/N dan P2O5 tersedia tinggi, (3) N total, sedang dan (4) mempunyai KapasitasTukar Kation (KTK) efektif dan potensial, Ca dan Mg rendah. Tekstur tanah mempunyai kandungan fraksi lempung30 persen, pasir 42 persen dan debu 28 persen. Tanah tambak di Muara Jawa dan Muara Pantauan lebih suburdibandingkan dengan tanah tambak di Muara Badak dan Samboja. Pada semua lokasi penelitian, berdasarkan hasilanalisis tanah cocok untuk usaha pertambakan, namun untuk lokasi Muara Badak dan Samboja agar produktivitastambak optimal, kesuburan tambak perlu ditingkatkan. Selain itu, KTK tanah di semua lokasi tambak rendah, makapenambahan hara/pupuk untuk meningkatkan kesuburan tanah tambak sebaiknya tidak diberikan secara berlebihankarena rentan terhadap pencucian.Kata kunci: analisis tanah, kesuburan, tambak