Geoscience Reference
In-Depth Information
3
History of Ground-
Penetrating Radar
Applications in Agriculture
M. E. Collins
ContentS
3.1 Introduction ........................................................................................................................... 45
3.2 Soil Surveying Using GPR.................................................................................................... 46
3.3 Direct GPR Applications to Agricultural Investigations ...................................................... 46
3.4 Indirect GPR Applications to Agricultural Investigations.................................................... 48
3.5 GPR Applications to Study Plants ........................................................................................ 50
3.6 GPR Golf Course Studies ..................................................................................................... 50
3.7 Incorporation of GPR and GPS into GIS .............................................................................. 51
3.8 Conclusions ........................................................................................................................... 51
References ........................................................................................................................................ 53
3.1 IntRodUCtIon
There has been a tremendous amount of literature written on the utilization of geophysical tech-
niques for agricultural research in the last 20 or more years. These geophysical techniques include
ground-penetrating radar (GPR), electromagnetic methods (EMs), metal detection, magnetometry,
and resistivity. But much of what has been published is associated either directly or indirectly with
the use of GPR for agricultural analysis.
The use of GPR as a geophysical technique to study its performance in the agricultural dis-
cipline was applied to study the variability of soils in Florida in the late 1970s. The success of
GPR to investigate ranges in soil properties and facilitate the mapping of soils in Florida led to
the incorporation of GPR as a routine field instrument in the Florida Cooperative Soil Survey Pro-
gram. From this early achievement, the use of GPR in the agricultural arena blossomed to monitor
direct and indirect applications of GPR to agricultural situations. Direct applications include those
investigations that have an immediate impact on agricultural production and management. These
applications may include such examples as determining limited soil depth restricted by bedrock,
hardpan, or a shallow water table; surveying root biomass in a loblolly pine forest; assessing stress
in citrus trees; and mapping shallow underground soil features affecting agricultural production.
Indirect applications may consist of, but are not limited to, investigating hydrocarbons in soil, locat-
ing buried drainage pipes, estimating moisture contents in the vadose zone, detecting coarse layers
in a sandy soil, evaluating subsurface pathways for nitrogen loss, and identifying offsite movement
of agrochemicals. As you may imagine from this list, GPR has been used more to investigate soils
than agricultural plants. Even though several geophysical techniques have been used for agricultural
reasons, this chapter will restrict its major discussion to the use of GPR as a geophysical tool in the
agricultural environment.
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