Mapping the Extent of Free Calcium Carbonate in the Soils of Madurai District, Tamil Nadu and Its influence on Micronutrient Availablity Using GIS Techniques

摘要

An extensive study was conducted to delineate the calcareous soils in Madurai district of Tamil Nadu, India. A total of 1724 geo referenced surface soil samples have been collected from all the 13 blocks of the district and analyzed for free CaC03 content. The observations showed minimum lime content (0.75 %) only in a few samples. Most of the samples showed moderate levels of calcareousness i.e. 5 to 10 %. Calcareous lands are spread in patches in Madurai district. Some of the blocks viz; Madurai East, Madurai West, Kottampatty, Sedapatty, Kallikudi, Chellampatty, Usilampatty and Alanganallur blocks possess non calcareous soils. Thirupparankundram (6.00%), Melur (6.00 %), T. Kallupatti (8.00 %), Thirumangalam (6.00 %) and Vadipatti (6.00 %) blocksshowed moderate level of lime. However, according to Piper (1966) classification, the average calcareousness of each block was found to be in non calcareousness (3.07 %) category.