FARMLAND COMPACTION STUDY USING A HIGH FREQUENCY SURFACE WAVE METHOD

For soil exploration in the vadose zone, a high-frequency multi-channel analysis of surface waves (HF-MASW) method has been developed with several enhanced techniques. In this study, we applied this enhanced HF-MASW method to study compaction effects on a farmland. The testing site was located at the Mississippi Agriculture and Forestry Experiment Station facility at Pontotoc, MS. The soils were compacted using a tractor. Two-dimensional HF-MASW surveys were conducted on both non-compacted and compacted sites. The vertical cross-section images in terms of the shear (S)-wave velocity were obtained and compared between the compacted and non-compacted soils. It was found that the compaction causes a significant increasing in the S-wave velocity on the top 20 cm soil. The compaction can affect soil properties down to 60 cm deep. The study demonstrates the capability of the HF-MASW method to noninvasively assess compaction effects.