Influence of Vegetation on Water Repellency in Selected Western Wisconsin Soils
1978
Richardson, J. L. | Hole, F. D.
Water repellency in several western Wisconsin soils was characterized by three tests: wetting angle (θ), wetting drop penetration-time (WDPT), and 90°-surface tension (γη). It appears that the high contents of organic matter in the A horizon of Mollisols and Alfisols are associated with slight repellency as measured by θ and WDPT. Frequent burning of a prairie on a Mollisol increased persistence (WDPT) and γη, as compared with soil at a nearby control site, but had no influence on θ, indicating that repellency is present at initial water contact but is unstable and disappears with prolonged water contact. Mor litter layers having observable fungal mycelia had repellent surfaces as measured by all three of the above tests. These repellent materials were observed in Spodosols under red pine (Pinus resinosa), hemlock (Tsuga canadensis), and under a mixed hard and soft wood stand with dense ericaceous shrub understory. The repellency of mor horizons of Spodosols may relate in some significant way to process of genesis of Spodic horizon.
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