Effect of Soil Particle Sizes on Determination of pH, Oxidizable Organic Carbon and Available Phosphate

Abstract

Soil analysis is integral part of present agricultural farming, where soil samples are particularly determines with 2 mm sieved soil. It is highly related that finer particles pass through 80 mesh (0.2 mm) size had better interaction with concentrated chemical solution or extractant. Total 136 number of soil sample were collected from different agricultural land of Terai region of West Bengal to conducted the study on effect of soil particle sizes passes through 20 mesh (2 mm) and 80 mesh (0.2 mm) sieve on soil pH, oxidizable organic carbon and available phosphate. Thus, each sample was portioned into two particle size classes. Such as ‘80 mesh soil particles’ and ‘20 mesh soil particles’. The pH, oxidizable organic carbon (OCC) and available phosphate contents of two particle sizes of each soil sample were determined and compared. The maximum difference of 0.2 unit was recorded in case of pH analysis with both sieve sizes. The mean organic carbon content of soil particles that passed through 20 mesh 80 mesh sieve was 0.674 and 0.683 respectively, which further signifies organic carbon content value of 80 mesh soil particle size was slightly greater than that of 20 mesh soil particle size. The value of P content by different sieve size had maximum difference 0.2 kg P2O5 ha-1 and for some soils there was no difference. The difference mean of phosphate values of two particle sizes was 0.134 only. This difference is neglected for crop production. Thus, soil sieved through two sieve sizes 20 mesh 80 mesh sieve had no effect with soil pH, little influence on OCC and negligible effect on available phosphate content.