Deep Soil Core Nutrients

*We have hypothesized that large rhizobial population densities can
occur at considerable depths in woody legume systems where deep
moisture also occurs. However, associated with deep soil
environments are low concentrations of soil nutrients that might
affect nodulation and also limit survival of free-living rhizobia.
The objectives of this study were to (1) determine if results from a
previous study of a mesquite woodland utilizing groundwater in the
Californian Sonoran desert were generizable to mesquite systems in
other deserts where root depth varied with ecosystem type and (2)
examine possible relationships of soil properties and host-plant
phenology to rhizobial concentrations.
Data set contains total nitrogen, total phosphorous,NH4-N, NO3-N,
PO4-P, percent moisture, total roots, tap roots, fine roots,
vesicular arbuscular mycorrhiza, rhizobia Most Probable Number, and
Rhizobia log (1+MPN).