Feather meal, a semi-slow-release nitrogen fertilizer for organic farming
- 425 Downloads
Plant nutrition in organic farming is based entirely on decomposition of organic materials, and release of excess N superfluous to the microbial population. Feather meal (FM), a by-product of the poultry processing industry, which contains 15% N as non-soluble keratin, is a potential organic N fertilizer. The objective of this study was to determine the rate of N mineralization and changes in microbial activity following the application of FM to soil. Soils were incubated with FM for 8 weeks at 30°C and optimal water content, and analyzed periodically for inorganic N, rate of CO2 evolution, counts of microbial populations, and activity of dehydrogenase and protease. Approximately 45, 55 and 65% of fertilizer N were released after 1, 2, and 8 weeks, respectively. Total number of bacteria increased due to the addition of FM after only 1 d, with a second pulse obtained at 14 d. Dehydrogenase activity followed a similar response cycling. Cellulose hydrolyzing bacteria and proteolitic bacteria increased later, between 5 and 21 d, probably due to secondary microbial decay products. Microbial biomass N at 5 to 7 d accounted for 10 to 14% of total FM-N, therefore the slow release of N from FM was due in part to its resistance to decomposition and in part to microbial biomass build-up and secondary decomposition.
Key wordsCO2 evolution feather meal microbial populations N fertilizers N mineralization organic fertilizers soil enzyme activity
Unable to display preview. Download preview PDF.
- Alexander M (1961) Introduction to Soil Microbiology, pp 310–311. John Wiley & Sons, Inc., New YorkGoogle Scholar
- Anderson JPE (1982) Soil respiration. In: Page ALet al. (eds) Methods of Soil Analysis, Agronomy 9, Part 2, 2nd edn, pp 831–871. American Society of Agronomy, Madison, WIGoogle Scholar
- Bielorai R, Iosif B, Neumark H and Alumot E (1982) Low nutritional value of feather-meal protein for chicks. J Nutr 112: 249–254Google Scholar
- Brookes PC, Landman A, Pruden G and Jenkinson DS (1985) Chloroform fumigation and release of soil nitrogen: A rapid direct extraction method to measure microbial biomass nitrogen in soil. Soil Biol Biochem 17: 837–842Google Scholar
- Ciavatta C, Gavi M, Vittori Antisari L and Sequi P (1990) An enzymatic approach to the determination of the degree of stabilization of organic carbon in fertilizers. Fert Res 25: 167–174Google Scholar
- Hadas A and Rosenberg R (1992) Guano as a nitrogen source for fertigation in organic farming. Fert Res 31: 209–214Google Scholar
- Hadas A, Bar-Yosef B, Davidov S and Sofer M (1983) Effect of pelleting, temperature and soil type on mineral nitrogen release from poultry and dairy manures. Soil Sci Soc Am J 47: 1129–1133.Google Scholar
- Hoffman Y and Teicher K (1957) Enzyme systems of our durable soils. VII Proteases. Pflanzenern Dung Bodenkd 77: 243–251Google Scholar
- Tabatabai MH (1982) Soil enzymes. In: Page ALet al. (eds) Methods of Soil Analysis. Agronomy 9, Part 2, pp 937–940. American Society of Agronomy, Madison, WIGoogle Scholar
- Wollum AG II (1982) Cultural methods for soil microorganisms. In: Page ALet al. (eds) Methods of Soil Analysis. Agronomy 9, Part 2, 2nd edn, pp 791–796. American Society of Agronomy, Madison, WIGoogle Scholar