1Central Institute of Brackishwater Aquaculture, Chennai-600028
2Indian Agricultural Research Institute, New Delhi, 110 012
3Regional Agricultural Research Station, Pattambi, Kerala, 679 306
4Orissa University of Agriculture and Technology, Bhubaneswar, 751 003
5Indian Institute of Soil Science, AICRP-LTFE, Bhopal, 462 001
*Corresponding Author Email: Division of Soil Science and Agricultural Chemistry, Indian Agricultural Research Institute, New Delhi, 110012, India, Tel.: 8505957906, Fax: 91-11-25846420 and E-mail: tpurakayastha@gmail.com
Online published on 17 February, 2017.
Fine textured soil have greater potential for physical protection of soil organic matter (SOM) as compared to coarse fraction. One of the principal factor responsible for the association of C with silt and clay fraction is soil texture and clay minerology. Our hypothesis was to study how soils with dissimilar climate texture and duration of manuring and fertilization influence C retention in two Alfisols with similar clay mineralogy (kaolinite dominant). The C carrying capacity of silt+clay fraction was estimated by a mathematical model developed by Hassink (1997). The study revealed that texture plays a significant role in determining C carrying capacity of silt and clay fraction of Alfisols of Bhubaneswar, Odisha and Pattambi, Kerala. The sandy clay loam soils of Pattambi stabilized more silt+clay protected C than sandy loam soil of Bhubaneswar. The application of 100%NPK, 150% NPK and 100% NPK+ FYM promoted stabilization of C in silt and clay fraction compared to 50% NPK and unfertilized control treatment. In general, the C retention potential of subsoil was higher than the surface-soil at both the sites indicating greater C sequestration potential.
Silt+clay fraction, C carrying capacity
