Decomposing the complexity of species coexistence patterns: an example from a semiarid grassland-shrubland transition zone

TitleDecomposing the complexity of species coexistence patterns: an example from a semiarid grassland-shrubland transition zone
Publication TypeConference Paper
Year of Publication1999
AuthorsHochstrasser T., Peters DC
Conference Name5th World Congress, International Association for Landscape Ecology
Date PublishedJuly 29-August 3
Conference LocationSnowmass Village, Colorado
ARIS Log Number100569
AbstractOne of the greatest difficulties in species diversity studies is to understand the biotic and abiotic factors driving coexistence patterns at the landscape scale. Our objective was to decompose the complex patterns of species coexistence on a landscape into a multiscale, stratified mosaic of habitat types. We defined the structure of a number of factors (soil texture, kangaroo rat burrows and presence of dominant grasses or shrubs) at a grassland/shrubland ecotone in central New Mexico, USA and evaluated plant species diversity associated with each factor. We measured species diversity for each habitat type on the appropriate scale defined by each factor. Because the spatial pattern of soil texture was correlated with the other two factors, the effect of dominant plants and kangaroo rats could not be completely separated from effects of soils. We found important differences between the number and abundance of species coexisting with dominant grasses compared to shrubs. Species diversity was negatively correlated with the density of dominant plants, yet was positively related to burrowing activities of kangaroo rats. Our results demonstrate the importance of stratifying the landscape based on biotic and abiotic factors in order to distinguish the separate effects of each factor on species coexistence patterns.