Characterization and Classification of Soils of Harve-1 Microwatershed of Chamarajanagar District, Karnataka, India

Aims: The detailed survey of the microwatershed was carried out by using digitized cadastral map as a base. The objective of the investigation was undertaken to characterize and classify the soils of Harve-1 microwatershed of Chamarajanagar district, Karnataka.

Place and Duration of Study: soil survey was done and soil samples were collected from Harve-1 microwatershed of Chamarajanagar district in the year 2016. The laboratory characterization and soil classification work was done at National Bureau of soil survey and land use planning, Regional centre Hebbal, Bangalore, Karnataka.

Methodology: Using Cartosat-1 and LISS-IV merged satellite data at the scale of 1:7920 were used in conjunction with the cadastral map as a base. Soil profiles were exposed and location of soil profiles was recorded using GPS and studied from each landform for describing morphological characteristic as per the guidelines given in USDA soil survey manual (Soil Survey Staff 2014). Based on the soil-site characteristics, ten soil series were identified using the method employed by Reddy (2006). Horizon wise soil samples were collected, processed and analysed for various properties by adopting standard procedure.

Results: The study showed that, the soils were moderately shallow to moderately deep in depth. The colour of the soils varied from dark red to dark reddish brown. Texture of the soil varied from sandy loam to sandy clay loam in surface and sandy clay loam to sandy clay in subsurface. The structure was weak medium sub-angular blocky to moderate medium sub-angular blocky throughout the profile in all series. The consistency of majority of the soils were friable, slightly sticky and slightly plastic in surface and friable, moderately sticky and moderately plastic in subsurface. Soil reaction varied from slightly acidic to alkaline (5.70 to 8.18) in nature. Organic carbon content of the soils was low to high (0.20 to 1.24 per cent). Calcium and magnesium are dominant exchangeable cations followed by sodium and potassium. The CEC of the soils ranged from 3.17 to 25.76 cmol (p+) kg-1. Major proportion of soil series in the microwatershed belonged to the order of Alfisols (Paralitic Rhodustalfs, Typic Rhodustalfs, Typic Haplustalfs and Rhodic Paleustalfs) except Honnenahalli (HNH) series belong to the order of Inceptisols (Typic Haplustepts).

Conclusion: The soils of the microwatershed were comes under the order of alfisols and inceptisols. This generated information can help the researchers, farmers and planners to manage the natural resources for future planning and also to achieve sustainable productivity.