Soil Physical and Chemical Properties of Several Soil Order in Suboptimal Dryland of Aceh Besar District, Indonesia

ABSTRACT The appropriate management of suboptimal dryland expands potentially agricultural areas because the soil properties in such an area are very diverse in each region and agroclimatic zone. A field study and laboratory analysis have been carried out to assess soil chemical characteristics in several soil orders in suboptimal dryland of Aceh Besar District, Indonesia. There are five soil orders representing soil types in the areas, namely Inceptisol Blang Bintang, Andisol Saree, Mollisol Krueng Raya, Ultisol Jantho, and Oxisol Lembah Seulawah. Samples were taken for each horizon layer from the soil orders. Analyses of the soil physical and chemical properties were done, including texture, pH (in H2O and KCl), organic C , total N, total P2O5 and K2O contents, available P, exchangeable base cations (Ca-, Mg-, K-, and Na-exch), potential cation exchange capacity (CEC), Al- and H-exch., base saturation (BS), and electrical conductivity (EC). The results showed that soil physical properties and chemical characteristics varied between soil orders, but soil fertility status in some soil orders was predominantly low. This low fertility status is indicated by acid soil reaction (pH 5.25- 6.48), low total C (<10 g/kg), low total N (0.7–2.7 g/kg), and low of bases saturation (<40%), so that these soils require the addition of soil amendments and fertilizers. Soil orders with low soil fertility are Oxisols, Ultisols, and Inceptisols, while other soil orders such as Andisol and Mollisol are classified as medium soil fertility. The order of soil quality from the highest to lowest is: Mollisols = Andisols > Ultisols = Oxisols = Inceptisols