Authors: Bidisha Majumder Biswapati Mandal P K Bandyopadhyay
Publish Date: 2007/07/24
Volume: 44, Issue: 3, Pages: 451-461
Abstract
Labile fractions of soil organic C SOC can respond rapidly to changes in C supply and are considered to be important indicators of soil quality An attempt is made in this paper to investigate into the dynamics of total organic C C tot oxidisable organic C C oc very labile C C frac 1 labile C C frac 2 less labile C C frac 3 nonlabile C C frac 4 microbial biomass C C mic mineralizable C C min and particulate organic C C p in relation to the system productivity of a 20yearold rice Oryza sativa L–berseem Trifolium alexandrium L cropping system with different management strategies no fertilization only NPK and NPK + FYM farmyard manure applied in different seasons in the hot humid subtropics of India Cultivation over the years caused a net decrease while balanced fertilization with NPK maintained the SOC About 62 of the C applied as FYM was stabilized into SOC The passive pool C frac 3 + C frac 4 constituted about 55 of the C tot A larger proportion 63 of applied C was stabilized in the passive pool of SOC Of the analysed pools C frac 1 C mic C p and C min were influenced most by the treatments imposed and explained higher per cent variability in the yield of the cropsAuthors are extremely grateful to Dr LN Mandal former Professor of Soil Science Bidhan Chandra Krishi Viswavidyalaya West Bengal for reviewing the draft manuscript They are also thankful to Dr S Kundu Vivekananda Parvatiya Krishi Anusandhan Sansthan Almora for helping analysis of C by CHN analyser and to the Indian Council of Agricultural Research New Delhi for funding the work through the World Bankassisted multiinstitutional collaborative National Agricultural Technology Project
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