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Nitrogen fixation by microbial crusts from desiccated Sahelian soils (Niger)

Malam Issa, O. and Stal, L.J. and Défarge, C. and Couté, A. and Trichet, J. (2001) Nitrogen fixation by microbial crusts from desiccated Sahelian soils (Niger). Soil Biology & Biochemistry, 33, 1425-1428. ISSN 0038-0717.

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Cyanobacterial crusts developing on the sandy and loamy soils of fallow lands in the Sahel (Niger) were investigated for their potential to fix nitrogen. Three sites were selected in this and environment, differing in sediment type and species composition. In the sandy sites heterocystous nitrogen-fixing cyanobacteria were present, whereas the loamy site did not contain such species. All sites showed light-dependent nitrogenase activity, starting within 2 h after re-wetting of the desiccated crust samples. Inhibition of photosystem II caused a decrease of nitrogenase activity in the samples with heterocystous cyanobacteria, but was stimulatory in the non- heterocystous crust. The results suggest that cyanobacterial crusts may be important for the improvement of the soil by enriching it with nitrogen. [KEYWORDS: nitrogen fixations; cyanobacteria; microbiotic crusts; arid and semi-arid environments Western negev desert; cyanobacteria; photosynthesis; mats]

Item Type:Article
Institutes:Nederlands Instituut voor Ecologie (NIOO)
ID Code:11041
Deposited On:24 Nov 2011 01:00
Last Modified:31 Mar 2014 10:43

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