SELECTION OF MICROORGANISMS IN A SPATIALLY EXPLICIT ENVIRONMENT AND IMPLICATIONS FOR PLANT ACCESS TO NITROGEN

Authors
Citation
Ap. Kinzig et J. Harte, SELECTION OF MICROORGANISMS IN A SPATIALLY EXPLICIT ENVIRONMENT AND IMPLICATIONS FOR PLANT ACCESS TO NITROGEN, Journal of Ecology, 86(5), 1998, pp. 841-853
Citations number
59
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Ecology
Journal title
ISSN journal
0022-0477
Volume
86
Issue
5
Year of publication
1998
Pages
841 - 853
Database
ISI
SICI code
0022-0477(1998)86:5<841:SOMIAS>2.0.ZU;2-8
Abstract
1 Evolution of a microbial nitrogen-uptake strategy that removes nitro gen at less than the maximum potential rate creates soil environments favourable for increased plant access to nitrogen. Plant productivity is thus increased, and achievement of maximum microbial biomass is fac ilitated through increased microbial access to plant-derived carbon. 2 Simulations show that micro-organisms exhibiting such a 'strategic' n itrogen uptake will be competitively excluded by more voracious micro- organisms in a homogeneous system, but can persist in a spatially expl icit system. This persistence of less voracious micro-organisms contra sts with the frequently held view that micro-organisms in soil systems take up nitrogen at the maximum possible rate. 3 The selection of str ategic or voracious microbial types in a spatially explicit environmen t is sensitive to the frequency of plant and microbial disturbance, an d to the rate of diffusion of inorganic nitrogen in the soil system. I n particular, the strategic (less voracious) microbial types are favou red under conditions of low plant disturbance, low to moderate diffusi on of inorganic nitrogen, and moderate microbial disturbance. 4 When s election favours strategic microbial types, plant access to nitrogen i s increased. Plants may also evolve strategies in a spatially explicit environment that will increase population densities of favourable, st rategic microbial types.