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<br />DeByle, N.V., 1973, Broadcast burning ofloggilng residues and the water repellency <br />of soils: Northwest Science, v. 47, no. 2, p. 77-87. <br />This investigatioE focused specifccally on water-repellent soils in nonhern coniferous forests, <br />before and after the burning of logging residues. As a result, th" information presented <br />offers a contrast to studies con ducted in chaparral settings. The: introduction describes <br />occurrences of water-repellent soils in unburned settings resulting from vegetation, <br />microorganisms in the soil, and organ.c matter. It also discusses prior research on water <br />repellency intensified by fIre, including temperatures and durations of heating that enhanced <br />or destroyed the condition. In this study, researchers observed that dry, deciduous litter was <br />very water repellent, but that the mineral portion of the soil ,:xhibited only sporadic <br />repellency. This water repellency was only found to increase in intense fire situations (i.e. <br />wildfIres and "jackpot" slash burns), and was temporary. The au'hor speculated that the <br />water repellency (when it existed) was short-lived due to the fine-teKtured nature of soils in <br />the study area, and that the general lack of repellency following p :escribed burns was the <br />result of high soil moisture conditions. He suggested that wildfires produce more repellency <br />because they tend to occur when the soil is relatively dry (thus creat ng extreme temperature <br />gradients), and that repellency ur.der sla.sh piles results from the hig: 1 temperatures and long <br />durations of burning that subsequently evaporate soil water. Sirnila:ly, chaparral tIres result <br />in more extensive water repellency due to the higher burn intensities and lower soil-moisture <br />conditions associated with chaparral set1:ings. The latter also tend to occupy coarser-textured <br />soils, thus enhancing water repellen:y. <br /> <br />Dekker, L.W., and Ritsema, C.J., 1994, How water moves in a v'ater repe:llent sandy <br />soil-i. Potential and actual water repellency: Water Reliources Research, v. <br />30, no. 9, p. 2507-2517. <br />The first in a series of papers by :Jekker and Ritsema analyzing fingc:rlike wetting patterns in <br />water-repellent soils. This "finger flow", as it is referred to, describes the pattern of <br />infiltration whereby a soil becomes wet in only a few places, and th ~ rest remains dry. It is <br />signifIcant because it indicates tlle process of preferential flow thnugh the wetted zones, <br />causing surface waters to reach tte groundwater more rapidly than b I homogeneous wetring. <br />Although finger flow has been de;cribed in other situations (i.e. layered soils), this study <br />examines the phenomenon speci:acally in water-repellent soils :dune sands). It also <br />introduces the concept of "potential" and "actual" water repel ency. Potential water <br />repellency refers to measurements performed on oven-dried samples, while actual water <br />repellency refers to fIeld-moist samples. The introduction contuns a literature review <br />summarizing the causes of wate! repellency in soils. Also includec in this paper is a brief <br />discussion on the relationship between liquid-solid contact angle and surface tc:nsion. <br /> <br />Dekker, L.W., and. Ritsema, C.J., 1995, Pingerlike wetting pattl:ms in two water- <br />repellent loam soils: JOIlll:1Ilal of Environmental Quality". 24, p. 324-333. <br />This study examined the occurrence of finger flow in water-repellelt soils (specifIcally in a <br />silt loam and silty-clay loam). The results indicated that fingered flow occurred even in <br />places with a relatively low degree of water repellency, and that "lingers" in fine-textured <br />soils were wider than in sandy soils. <br /> <br />14 <br />