The Influence of Climate, Soils, Weather, and Land Use on Primary Production and Biomass Seasonality in the US Great Plains

BRADFORD JB, WK LAUENROTH, IC BURKE AND JM PARUELO

ECOSYSTEMS (NEW YORK. PRINT)

Año: 2006 p. 934 - 950

1432-9840

ABSTRACTIdentifying the conditions and mechanisms that production is primarily spatial, whereas variationcontrol ecosystem processes, such as net primary in seasonality is more evenly split between spatialproduction, is a central goal of ecosystem ecology. and temporal components. Our statistical (multi-Ideas have ranged from single limiting-resource ple linear regression) models explained more oftheories to colimitation by nutrients and climate, the variation in the amount of primary produc-to simulation models with edaphic, climatic, and tion than in its seasonality, and more of thecompetitive controls. Although some investigators spatial than the temporal patterns. Our resultshave begun to consider the influence of land-use indicate that although climate is the mostpractices, especially cropping, few studies have important variable for explaining spatial patterns,quantified the impact of cropping at large scales cropping explains a substantial amount of therelative to other known controls over ecosystem residual variability. Soil texture and depth con-processes. We used a 9-year record of produc- tributed very little to our models of spatial vari-tivity, biomass seasonality, climate, weather, soil ability. Weather and cropping deviation bothconditions, and cropping in the US Great Plains made modest contributions to the models ofto quantify the controls over spatial and temporal temporal variability. These results suggest that thepatterns of net primary production and to esti- controls over seasonality and temporal variationmate sensitivity to specific driving variables. We are not well understood. Our sensitivity analysisconsidered climate, soil conditions, and long-term indicates that production is more sensitive toaverage cropping as controls over spatial patterns, climate than to weather and that it is very sen-while weather and interannual cropping varia- sitive to cropping intensity. In addition to iden-tions were used as controls over temporal vari- tifying potential gaps in out knowledge, theseability. We found that variation in primary results provide insight into the probable long-and short-term ecosystem response to changes inclimate, weather, and cropping.