allocation of inorganic nitrogen (15NH4+ ) to soil, microbial and plant biomass in an Arctic salt marsh.
Published: 2004
Language: eng
Number of pages: 107
Description: This study has demonstrated, through the shared distribution of a single resource (15NH4+), that plants and soil microbes compete for inorganic N in a N-limited system. At La Perouse Bay, soil microorganisms out-compete plants for this resource, but their competitive advantage is dampened relative to microorganisms in other Arctic ecosystems by the effects of goose grazing that promote plant growth via the addition of faeces. There is a seasonal displacement of N allocation, as microbes continue to mineralize and slowly immobilize nitrogen in the winter. Loss of vegetation, as a result of goose grubbing, has led to changes in soil characteristics, including high salinity and low redox potentials. These edaphic conditions may dampen N-uptake by soil microorganisms in these disturbed soils. Seasonal and grazing effects interact to contribute to a large potential N loss from these soils, although this is minimized by the apparent abiotic fixation of inorganic N.
Notes: Adviser:  Robert L. Jefferies.

Thesis (M.Sc.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Masters Abstracts International, Volume: 43-03, page: 0770.

MICR copy on microfiche (2 microfiches).