Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/1/2003
Publication Date: N/A
Technical Abstract: Our objective was to determine the relationship between short term substrate use and longer term C storage. It was hypothesized that the metabolic status of the soil measured by substrate utilization may be a predictor of ecosystem C storage. To test this hypothesis we used similar soils from a climate (elevation) gradient in the semi-arid shrub-steppe. We measured the response of these soils to six 14C labeled substrates ranging from glucose to acetic acid. The response as predicted was variable across substrates. However, the lower elevation sites (hotter/drier) mineralized substrates such as glucose and acetate more slowly with more remaining after 15 days. In contrast there was no difference among sites with respect to arginine mineralization. In general it appears that the more rapid short term mineralization of substrates will influence the longer term C storage of soils. This result could be due to the differences in fungal:bacterial ratios which will be presented and discussed.