Tingkat Perkembangan Tanah Berdasarkan Pola Distribusi Mineral Liat Di Kecamatan Lumbanjulu Kabupaten Toba Samosir: The level of soil development based on the pattern of clay mineral distribution in Subdistric Lumbanjulu, Distric of Toba Samosir

Perkembangan tanah dapat dicirikan oleh distribusi dan komposisi mineral di dalam tanah. Tujuan penelitian ini adalah untuk mengetahui tingkat perkembangan tanah berdasarkan pola distribusi mineral liat. Penelitian ini dilakukan di Desa Sionggang Selatan, Jangga Toruan, Sibaruang dan Hatinggian, Kecamatan Lumbanjulu Kabupaten Toba Samosir dari pada bulan Juli 2015 sampai April 2016.Dilakukan deskripsi profil tanah untuk menentukan sifat morfologi tanah sementara sifat fisik dan kimia dilakukan dengan analisis laboratorium. Analisis mineral liat menggunakan Differential Thermal Analysis (DTA). Hasil penelitian menunjukkan bahwa profil 1 (horizon Ap, Bw1, Bw2, B/C) dengan pola maksimum merupakan tanah Inceptisolyang mulai berkembang. Profil 2 (horizon Ap, Bw1, Bw2, Bw3) dengan pola menurun dan meningkat merupakan tanah Inceptisolyang mulai berkembang. Profil 3 (horizon A, B/A, Bw1, Bw2) dengan pola meningkat merupakan tanah Inceptisol yang mulai berkembang. Profil 4 (horizon A, Bw1, Bw2) dengan pola maksimum merupakan tanah Inceptisol yang mulai berkembang.   Soil development can be characterized by the distribution and composition of minerals in the soil. The aim of this research was to determine the level of soil development based on the pattern of distribution of clay minerals. This research was held in Subdistric Lumbanjulu, Distric of Toba Samosir. It was located at North Sionggang Village, Jangga Toruan, Sibaruang and Hatinggian Village, Subdistric Lumbanjulu, Distric of Toba Samosir from July 2015 to April 2016. Morphological properties were identified by describing the soil profiles while physical and chemical properties were identified by laboratory analysis. Clay minerals analysed using Differential Thermal Analysis (DTA). The results showed that the profile 1 (horizon Ap, Bw1, Bw2, B/C) with maximum pattern of was Inceptisol have started to develop. Profile 2 (horizon Ap, Bw1, Bw2, Bw3) with pattern decreasing and increasing was Inceptisol have started to develop. Profile 3 (horizon A, B/A, Bw1, Bw2) with an increasing pattern was Inceptisol have started to develop. Profile 4 (horizon A, Bw1, Bw2) with maximum pattern was Inceptisol have started to develop