Recovery of Soil Penetration Resistance on Compacted Skid Trails after Forest Thinning in Central Hokkaido.

Abstract

5 (2018) Recovery of Soil Penetration Resistance on Compacted Skid Trails after Forest Thinning in Central Hokkaido. J Jpn For Soc 100: 110⊖115 Vehicular traffic on skid trails after forest thinning causes compaction, leading to increased soil penetration resistance. In this study, we investigated the recovery of soil penetration resistance after thinning in a planted Todo fir forest. The soil penetration resistance profile of upper soil (to a depth of 0.6 m) was measured on a skid trail before thinning (2008) , immediately after thinning (2008) , and 5 and 6 years after thinning (2013 and 2014, respectively). The penetration resistance profile revealed that a hard soil layer formed down to a depth of 0.2 m immediately after thinning; however, soil penetration resistance and the soil compaction index decreased 6 years after thinning. Thus, our results indicate that compaction effects on skid trails disappear 5 or 6 years after the event. A "soil compaction index" (SCI) was created to evaluate the degree of soil compaction. SCI can indicate the degree of soil compaction as one numerical value.

Application of Ground-Penetrating Radar and a Combined Penetrometer–Moisture Probe for Evaluating Spatial Distribution of Soil Moisture and Soil Hardness in Coastal and Inland Windbreaks

“…The soil hardness measurement mechanism using a CPMP is identical to that of the conventional dynamic cone penetrometer [18]. A dynamic cone penetrometer is a common tool for measuring soil hardness and for assessing the impact of soil compaction on trees in a variety of locations, including coastal windbreaks [13], man-made growth bases [23], and forests [24]. A CPMP is, therefore, appropriate for measuring soil hardness at sites with variable soil conditions.…”