Abstract

                                An attempt has been made on characterization of sodic soils by using reconnaissance soil survey methods in North Western Zone of Tamil Nadu encompassing the districts of Dharmapuri, Salem, Krishnagiri and Namakkal during January 2009 to August 2009. Surface soil samples were collected as per reconnaissance soil survey reports of Dept. of Agriculture and analyzed the soil pH and EC. Based on the analytical report the severity of sodicity problem was quantified. Then profiles were dug and detailed analyses were taken up in the sodic soil inflicted areas. Considerable area of sodic soils to the extent of 26,279 ha was identified under the soil series viz., Peelamedu, Salem, Mallur, Thulukkanur, Mallasamudram, Upparapatti, Periyanaickanpalayam, Nattam, Dharmapuri, Krishnagiri and Harur. Among the soil series detailed analysis of profile samples like pH, EC, ESP and SAR the Mallasamudram soil series was identified as most affected by sodicity. The pH range of the above series was 9.1 to 10.0, EC of 0.8 to 1.2 dsm -1 and ESP of 32 and 48 per cent was predominantly noticed compared to other soil series. The land capability and productivity classes were poor in the above soil series.

Key words : Soil characterization, North Western Zone, sodicity, land capability class (LCC).