Characterization, classification and evaluation of soil resources of a farm in hill zone of Assam

Abstract

Importance of soil classification and characterization of a research farm is well known. The aim of this study is to characterize and classify the soils of the Regional Agricultural Research Station (RARS) farm and evaluate the capability of land for sustainable management of the resources. A total of five (5) representative soil profiles were exposed, and their morphological, physical and chemical properties were studied for the purpose. Soils were deep, well drained except in few pockets with acidic to slightly alkaline (5.06-7.44) soil reaction. Sandy clay loam was the major soil texture in both new and old farm blocks. The CEC (6.40-11.14 cmol(p+)kg-1) of the soils were low and organic carbon ranged from low to high (3.30 g kg-1 to 8.90 g kg-1). The total exchangeable cations varied from 1.82-4.66 cmol(p+)kg-1 and decreased with depth. Significant positive correlation was observed between matrix hue and organic carbon (0.399**), texture and clay (-0.722**) and between bulk density and CEC (-0.845**). Soils of the major part of the Farm area were classified as Typic Hapludalf at the subgroup level and remaining part was qualified for Typic Dystrudept. The soils of the Farm were categorized as class III and class IV of the land capability classification system. The class III soils were further subdivided to two sub-classes because of limitations in soil (such as, low water holding capacity) and water stress and the class IV soil was placed in one subclass having problem related to water logging.