Organic Manures for Maintaining Soil Productivity E13
Sangakkara, U. R. ; Marambe, B. ; Attanayake, A. M. U. & Gajanayake, J. N.
Faculty of Agriculture, University of Peradeniya, Sri Lanka.
|Soils of the developing world are considered
fragile, due to the low organic matter content and a poor fertility status. This has an
adverse bearing on the productivity of organic systems. Thus a study under controlled
conditions evaluated the benefits of using three different organic manures with a range of
C:N ratios on maintaining the organic matter content of soils and crop productivity.
Application of cattle manure, leguminous leaves alone or in a binary mixture produced high yields. Mixing each of these organic manures with coir dust which has a very high C:N ratio reduced yields marginally. Application of coir dust alone produced the lowest yields. However, the soil organic matter was maintained with the application of coir dust, either in mixtures with the other manures or alone. This was due to the slower breakdown of this material. Thus, the organic matter status of the soil and other selected physical attributes along with crop yields were maintained with the inclusion of coir dust. The benefits of mixing organic matter in maintaining productivity of organic systems are presented.
Fox, R. H.; Myers, J. R. & Vallis, I. (1990): The nitrogen mineralization rate of legume residues in soils as influenced by their polyphenol, lignin and nitrogen contents. Plant and Soil, 129, 251-259.
Handayanto, E.; Cadish, G. & Giller, K. E. (1995): Decomposition and nitrogen mineralization of selected hedge row prunings. In: Cook, H. K. & Lee, H. C. (eds.) Soil management in sustainable agriculture. University of London, U.K. 113-122.