||Regional and Local Vegetation Patterns: The Responses of Vegetation to Subcontinental Air Masses.
Neilson, R. P.;
King, G. A.;
DeVelice, R. L.;
Lenihan., J. M.;
||NSI Technology Services Corp., Corvallis, OR. ;Oregon State Univ., Corvallis.;Corvallis Environmental Research Lab., OR.
Time series analysis;
Air pollution effects(Plants);
Natural resources management
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
||Spatial patterns of biodiversity in plants were examined through a range of scales from continental and biome to patterns of local habitat variation. The authors propose a hierarchy of constraints on these patterns. Large-scale climate is proposed to structure continental patterns of species richness and the diversity and distribution of physiognomic types in the form of biomes. Within biomes regional climatic gradients modulate the length scales of habitats and, hence, the amount of substrate variation within a grain that is 'perceived' by an organism as homogeneous. Most resource variation in the core of biomes is within a given species' range of tolerance and large areas of the landscape are 'perceived' as essentially homogeneous. As one moves toward ecotones, the convergence of regional climatic stresses constrains the suitability of habitats to smaller scale variations in substrate and topography. Thus, the size of habitat grain declines, while the diversity of habitat grains increases toward biome ecotones. Biotic interactions form a third level of constraint, operating at yet a smaller spatial scale, to further modify local species associations. The regional gradients in habitat size and variability provide explanatory power of observed patterns in biodiversity and provide a monitoring tool for climate-induced changes in ecotones.
||Prepared in cooperation with Oregon State Univ., Corvallis. Sponsored by Corvallis Environmental Research Lab., OR.
||Reprint: Regional and Local Vegetation Patterns: The Responses of Vegetation to Subcontinental Air Masses.
||57H; 57C; 48B; 55C; 68A; 91A
||PC A03/MF A01