Abstract
Soil moisture and temperature regimes are based on Great Plain cropping systems which made the best substitute for the conceptualization of zonal climate categorization just before the undertaking of Soil Taxonomy by Guy Smith. Despite a classification system based on broad and gradual changes in precipitation and temperature, the system is uniformly adopted across the western mountainous region where temperature and moisture gradients can change abruptly. High variability in effective precipitation and temperature due to topographic and soil parent material influences relative to the silt dominated agricultural soils of the Midwest. Because of this variability and the inability to in-situ monitor (i.e., cost) the variability across vast western landscapes, reliance on correlative vegetation – soil indices are relied upon. Since actual soil moisture data is costly and takes 10 years to define a regime, SMRs are generally not quantitatively measured relative to the technical definition of an SMR across any given soil mapping survey. Therefore, the NRCS often relies on vegetation communities to assign SMRS; however, these vegetation communities within an SMR can often differ depending on the regional climatic and topographic characteristics. Our objectives are to: 1) evaluate soil moisture and temperature patterns across disparate climatic and topographic sequences within the Rocky Mountain region, but within a Xeric soil moisture regime; 2) test through in-situ soil moisture and temperature monitoring whether the climate profiles reflect the definitional attributes of a Xeric SMR: and, 3) evaluate through in-situ monitoring whether the assigned vegetation communities as currently mapped by region to the Xeric SMR, match the SMR defined by the monitoring data. Four regional locations (MLRA 6, 10, 43A, 43B) were selected for this research and reflect a range in climate, parent material, soil genesis, and vegetation communities within a xeric SMR. Five soil climate monitoring stations were installed in each region to capture variation in soil physical characteristics to test the validity of a xeric classification. Sites are monitored for volumetric water content at their designated soil moisture control sections and temperature at 10 & 50 cm as described in Soil Taxonomy. The monitoring stations will be observed for the next decade.