Fertilization practices alter microbial nutrient limitations after alleviation of carbon limitation in a Ferric Acrisol

Autor: Delwendé Innocent Kiba, Emmanuel Frossard, François Lompo, Ouakoltio Y.A. Traoré, M. C. Arnold, Andreas Fliessbach, Hassan Bismarck Nacro, H. R. Oberholzer, Astrid Oberson, Else K. Bünemann
Rok vydání: 2015
Předmět:
Zdroj: Biology and Fertility of Soils. 52:177-189
ISSN: 1432-0789
0178-2762
DOI: 10.1007/s00374-015-1061-9
Popis: Microbial nutrient limitation was investigated in a 53-year-old field experiment in the Central-West of Burkina Faso under sorghum–cowpea rotation, comparing three fertilization practices: mineral fertilizer (MIN), mineral fertilizer and farmyard manure (MINFYM), and a non-fertilized control (CON). We assessed microbial N and P limitation after removal of C limitation by (i) determining microbial N and P, (ii) assessing respiration kinetics in incubated soil samples amended with easily available C (glucose) alone or in combination with N and/or P, or not amended, and (iii) evaluating changes in microbial biomass and community composition at the peak of microbial respiration by microbial P and phospholipid fatty acid (PLFA) analyses. Microbial N and P were very low in all fertilization practices, but greater in MINFYM than in CON. Easily available C was the first factor limiting microorganisms in all fertilization practices. After removal of C limitation, most indicators suggested N and P co-limitation in CON. In contrast, respiration kinetics in MINFYM and MIN were only N-limited, while biomass formation in MINFYM was also P-limited. PLFA analyses indicated preferential fungal growth on the added C, and P limitation of changes in microbial community composition in MIN. Long-term application of fertilizers mostly alleviated secondary microbial nutrient limitation by P but not by N, and C always remained the primary limiting factor for microbial growth.
Databáze: OpenAIRE
Externí odkaz: