Judul: Stipulation of Soluble and Exchangeable Bases in Very High Base Saturated Soil
Abstrak: Adanya hasil pengukuran basa-basa dapat ditukar ekstraksi NH4OAc 1N menghasilkan kejenuhan basa (KB) sangat tinggi bahkan melebihi >100%. Hal ini mengindikasikan terekstraknya basa-basa terlarut dan basa-basa dapat ditukar. Nilai KB seharusnya ditetapkan dari bentuk basa-basa dapat ditukar. Pemisahan ekstraksi basa-basa terlarut dengan basa-basa dapat ditukar dilakukan untuk mendapatkan nilai KB yang lebih akurat. Penelitian ini bertujuan untuk menetapkan basa-basa terlarut dan dapat ditukar, serta beberapa parameter sifat kimia tanah yang berhubungan erat dengan KB yaitu Al-dd, H-dd, KTK efektif, pH tanah, dan P-tersedia pada tanah dengan KB sangat tinggi. Metode penelitian berupa analisis kimia tanah. Pemisahan ekstraksi dilakukan dengan pengekstrakan basa-basa terlarut terlebih dahulu menggunakan larutan BaCl2 0,01M kemudian dilanjutkan dengan pengekstrakan basa-basa dapat ditukar menggunakan larutan NH4OAc 1N. Hasil penelitian menunjukkan terdapat basa-basa terlarut dengan konsentrasi yang lebih besar dari basa-basa dapat ditukar, konsentrasi kation masam relatif rendah, KTK efektif tergolong sangat tinggi, pH tanah agak masam menuju netral, dan P-tersedia tergolong sangat rendah. Urutan konsentrasi kation basa terlarut dan dapat ditukar pada tanah sawah yaitu Mg>Ca>>Na>K sedangkan pada tanah hutan Mg>>Ca>>Na>K. Pemisahan ekstraksi bentuk basa terlarut dan dapat ditukar menghasilkan nilai KB yang lebih akurat karena bentuk basa terlarut tidak dihitung sebagai bentuk basa dapat ditukar. Kata kunci : larutan BaCl2 0,01M, larutan NH4OAc 1N, pemisahan ekstraksi, sifat kimia tanah., The measurement of exchangeable bases of some soils with 1N NH4OAc solution may resulted in very high base saturation (BS) even exceeding 100%. This might be that the extracted bases both in the forms of soluble and exchangeable bases. The BS value should be calculated only from exchangeable bases. So it is necessary to separate the extraction of soluble bases with exchangeable bases. This study was aimed to determine dissolved and exchangeable bases, as well as several parameters of chemical properties that are closely related to BS, namely exchangeable-Al, exchangeable-H, cation exchange capacity (CEC), pH, and available-P in soils with very high BS. Separation of the extraction was carried out by consecutive extraction of soluble bases using a 0.01M BaCl2 solution, and then proceeded with extraction of exchangeable bases using a 1N NH4OAc solution. The results showed that the presence of soluble bases with concentrations higher than the exchangeable bases. The concentration of acid cation was relatively low, CEC was very high, the soil pH was slightly acidic to neutral, and the available P was very low. The order of concentration of soluble and exchangeable base cations in ricefield was Mg>Ca>>Na>K in comparison to forest soil that was Mg>>Ca>>Na>K. Extraction to separate soluble and exchangeable bases forms results in a more accurate BS value since the soluble bases are included in the calculation of BS. Keyword : BaCl2 0,01M solution, extraction splitting, NH4OAc 1N solution, soil chemical properties.
Keyword: BaCl2, 01M solution, extraction splitting, NH4OAc 1N solution, soil chemical properties