Geophysical imaging is a powerful method for identifying soil spatial patterns at the plot to small watershed scale. Electromagnetic induction (EMI) is noninvasive and can be linked to a GPS and field computer to provide rapid spatial measurements.

Results/Conclusions

We are actively engaged in developing new methodologies with EMI to identify the relationship between soil spatial patterns and plant community structure. Results are presented from watershed surveys in Idaho and California that produce electrical conductivity maps of the top meter of soil, and that can be compared with the dominant vegetation patterns. Results indicate strong linkages between soil spatial patterns and vegetation patterns where no previous linkage could be quantified from traditional soil survey maps. The developed methodologies have worked well in fir and oak woodlands, but our new interest is to apply this in tropical forests to determine if relationships exist between forest spatial structure and soils. Preliminary measurements from Trinidad are presented and some of the technical difficulties in working in tropical forests discussed.