Biotic interactions between grazers and plants: Relationships contributing to atmospheric boundary layer dynamics

TitleBiotic interactions between grazers and plants: Relationships contributing to atmospheric boundary layer dynamics
Publication TypeJournal Article
Year of Publication1998
AuthorsDyer, MI, Turner, CL, Seastedt, TR
JournalJournal of Atmospheric Sciences
Volume55
Pagination1247 -1259
Accession NumberKNZ00637
Abstract

During 1987 and 1988 First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment (FIFE) studies conducted in the tallgrass prairie of central Kansas, variations in ungulate grazing intensity produced a patchy spatial and temporal distribution of remaining vegetation. Equally variable plant regrowth patterns contributed further to a broad array of total primary production that resulted in a pronounced mosaic of grazing impacts. This regrowth potential, derived from a relative growth rate (RGR) equation comparing ungrazed and grazed plants, determines much of the ecosystem dynamics within and among the grazed pastures and between years. Rates of change in new plant growth (DRGRg) ranged from 2100% to 140%; however, 78% of the time in 1987 and 71% in 1988, productivity increased as a function of grazing intensity. Since plant growth potential in ungrazed (RGRug) and grazed systems (RGRg) have inherently different attributes, interactions with the abiotic environment may develop many uncertainties. Thus, changes in growth rates in grazed areas compared to ungrazed areas (DRGRg) may impose major controls over system productivity and associated biological processes currently not accounted for in ecosystem models.
Because FIFE microsite atmospheric boundary layer (ABL) studies did not directly incorporate grazing intensity into their design, Type I and Type II statistical errors may introduce significant uncertainties for understanding cause and effect in surface flux dynamics. As a consequence these uncertainties compromise the ability to extrapolate microsite ABL biophysical findings to other spatial and temporal scales.

URLhttp://journals.ametsoc.org/doi/pdf/10.1175/1520-0469(1998)055%3C1247%3ABIBGAP%3E2.0.CO%3B2