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<br />Fink, D.H., 1970, Water repellency and inilltration resistance of orgarric-liIm-coated
<br />soils: Soil Science Socie:ty of America Proceedings, v. 34, p. 189-1'14.
<br />This research evaluated the effect> of various soil textures and nrganic f1lms on water
<br />repellency and inf1ltration resistance. The author concludes that the effective contact angle
<br />is independent of soil chemical ar..d physical properties. Instead, he ~ uggests that it is related
<br />to tile proportion of soil surface wvered with organic material, and to the structure of the
<br />hydrophobic group.
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<br />Fink, D.H., and Mitchell, S.T., 1975, Freeze-thaw effects on soils treated for water
<br />repellency, in Hydrology and 'Water Resources in Arizona and the Southwest:
<br />American Water Resources Association, Hydrology Sect on, Arizona Section,
<br />Arizona Academy of Sciences, Tempe, Ariz., April 11-12, 1975, Proceedings, v.
<br />5, p. 79-85.
<br />This study was initiated by Ihe failure Oittle to no runoff productiOlI) of a water harvesting
<br />catchment in Arizona that had been treated with paraffin wax in order to make the soil water
<br />repellent. Researchers hypothesiud that this failure was the result c f freeze-thaw processes
<br />that destroyed the artifIcially-induced water repellency of the soil. ~ lley performed a series
<br />of lab experiments on various soils ~nd found that coarser-textured s, )ils tended to withstand
<br />freeze-thaw cycling better than fIner-textured soils. Results als::> indicatl~d that since
<br />smoother plots retained less ponded water, they would be less like: y to suffe:r freeze-thaw
<br />damage. However, the investigation concluded that water repellency breakdown in the
<br />water harvesting catchmem was not due to freeze-thaw process :s, but to shrink-swell
<br />properties of the soil.
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<br />Foggin, G.T., and DeBano, L.JE'., 1971, Some geographic implications of water-
<br />repellent soils: Professional Geographer, v. 23, p. 347-351).
<br />This review paper includes general discussions of the nature of natu:ally-occurring and fire-
<br />induced water repellency, facto::s causing repellency, and geogr:lphic and geomorphic
<br />implications of water repellency. 'Water repellency of soils affect: the runoff cycle of a
<br />watershed. A repellent layer will promote surface runoff by reduci:r g infiltration rates. On
<br />burned plots, precipitation saturate,; only the thin, overlying soil, which may lead to sheet
<br />erosion and rill and gully fOlmation, Imense and concentrated infilcation may occur where
<br />burrow holes, tension cracks and root channels breach the repelle01 layer. This may allow
<br />surface runoff and near surface lateral flow to enter the deeper soil. ] ncreased surface runoff
<br />also adds to storm flow \\~thin the drainage network, removing material stored in the
<br />channels as well as contributing to channel scour. This increase in both discharge and
<br />sediment yield produces downstream flooding.
<br />
<br />Giovannini, G., and Lucchesi, 8., 1983, Effect of fire on hydrophobic and cementing
<br />substances of soil aggregates: Soil Science, v. 136, no. 4, p. 231-236.
<br />Researchers performed an experimental burn within the Sardinian I ~egional Forest in ltaly,
<br />to srudy the effects of fIre on some factors related to soil erodibility. The bum covered an
<br />area of approximately 100m2 in a chaparral-vegetated watershec. Soils derived from
<br />Paleozoic schists and sandstones exhibir,ed a slight natural repellency prior to burning, which
<br />the authors suggest was due to 6e incorporation of intensely hydr, )phobic organic matter
<br />into the mineral fraction. Fire destroyed this water repellency in th ~ surface horizons, and
<br />caused a decrease in organic malter content and aggregate stability In contrast, post-fire
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