Volume No. 4 Issue No.: 3 Page No.: 742-749 Jan.-Mar 2010

 

EFFECT OF SPENTWASH APPLICATIONS ON ORGANIC CARBON DYNAMICS IN SOIL

 

Kalaiselvi P.* and S. Mahimairaja

Department of Environmental Sciences, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu (India)

 

Received on : August 08, 2009

 

ABSTRACT

 

Distillery spentwash is used in agriculture as a source of plant nutrients and irrigation water. Being plant originated the spentwash contains all plant nutrients and organic matter. The effect of different levels and methods of spentwash application on organic carbon dynamics was examined through a field experiment. The field experiment was conducted using groundnut (Arachis hypogeal L.) as a test crop at Research and Development Cane Farm, The Salem Co-operative Sugar Mills Ltd., Mohanur, Namakkal District, Tamil Nadu (India). The different levels of spentwash was applied to the field in one time and continuous split doses of application. The spentwash with high BOD (12800 mg L-1) and C (24000 mg L-1)) has enriched the soil with organic matter and thus significantly increased (from 8.0 to 13.4 g kg-1)) the soil organic C. The increase was more due to one time application initially (before sowing), whereas, at later stages of crop growth (pod formation and harvest), organic C was higher due to continuous application. With advancement of time both with and without crop, the soil organic C was found decreased due to organic matter decomposition and C loss, mainly as CO2 from soil. Inspite of CO2 loss and crop assimilation, the organic C was significantly greater with the continuous application of split doses of spentwash. The spentwash was found to enhance the mineralization of both spentwash-C and soil-C.

 

Keywords : Spentwash, Organic carbon, Mineralization, One time and Continuous application, Groundnut, Plant nutrient

 

 

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