International Journal of Chemical Studies
Vol. 6, Issue 1 (2018)
Soil oxidisable carbon stocks, nutrient availability and enzyme activity in surface and subsurface soil layers as influenced by twelve years of organic farming
Author(s): S Sridevi, MV Ramana, M Goverdhan and K Suresh
Abstract: A study was conducted for 12 years on permanent plots from 2003-04 to 2014-15 at the College of Agriculture, Rajendranagar, PJTSAU to evaluate the impact of organic nutrient management (ONM) practices vis a vis chemical nutrient management (CNM) and Integrated nutrient management (INM) on soil quality and performance of crops using maize-onion as test crop sequence. Changes in Soil organic carbon (SOC) stocks, nutrient availability and biological activity in soil and depth influence of various nutrient management practices was evaluated at the end of 12th year. Soil bulk density was lower in all the depths under organic nutrient management though differences were nonsignificant. SOC stocks in 0-15 cm layer ranged between 21.45 to 25.40 Mg C ha-1 in organically managed plots and 21.69 Mg C ha-1 in INM and 16.60 Mg C ha-1 in chemical nutrient management plots. Superiority of ONM in terms of soil organic carbon stock was evident up to lower soil layers of 15-30 cm, 30-45 cm. But in deeper layers of 45-60 cm and 60-75 cm SOC stocks in all the treatments were on par. Availability of phosphorus after 12 years of experimentation in the surface layer was more under INM followed by ONM while CNM plots registered lowest amount of available P. In subsequent depths of 15-30 cm and 30-45 cm similar superiority of INM and ONM was observed over CNM. Similarly buildup of available potassium with ONM and INM was seen upto 30-45 cm soil depth. Soil enzyme activity was found to be influenced evidently only in the surface 0-15 cm and 15-30 cm soil layers. Activity of dehydrogenase was three fold higher in the surface 0-15 cm soil layer than 15-30 cm layer. Similarly two fold increased activity of acid and alkaline phosphotase enzymes activity was registered in surface layer when compared lower layer. Soil enzymatic activity in the lower layers was found to be not influenced by the nutrient management practices.
Pages: 512-516 | 458 Views 8 Downloads
How to cite this article:
S Sridevi, MV Ramana, M Goverdhan, K Suresh. Soil oxidisable carbon stocks, nutrient availability and enzyme activity in surface and subsurface soil layers as influenced by twelve years of organic farming. Int J Chem Stud 2018;6(1):512-516.