Organic Matter Contribution to Cation Exchange Capacity in Soils

The average cation exchange capacity contribution of organic matter alone was 242.61 m.e./100g and that of clay alone was 123.30 m.e./100g Organic matter and alay together accounted for 182.95 m.o./100g organic matter and clay as an exchange. complex had cation exchange capacity of 132.46 m.e./100g. The average organic matter content of the soils was 3.59 per cent and its contribution to cation exchange capacity averaged 8.76 m.e./100g soil. Similarly the average clay content was 42.62 per cent and the average of its contribution to cation exchange capacity was 46.70 m.e./100g soil. The percentage reductions in cation exchange capacity on account of the formation of organic matter clay complex as in the soils of Parbhani. Ambagogai. Mukhed. Vaijapur and Tuljapur were 47.15, 45.10. 11.40, 16.46 and 21.17 respectively. The average cation exchange capacity contribution of organic matter was about 15.56 per cent while clay accounted 84.40 per cent. It appeared that in tropical ecosystem as of Marathwada, clay largely constitutes the bulk of cation exchange properties of soils.