annual report of regional research project w-188 - NDSU

The 5-year project is studying the mechanism of: (1) convective thermal venting
of soil cracks and open fractures; and (2) the effect this thermal venting has on
enhanced ..... Military training exercises at the National Training Center (NTC), Ft.
Irwin, California have led to the degradation of large areas of the Mojave Desert.

Part of the document


ANNUAL REPORT OF REGIONAL RESEARCH PROJECT W-1188
January 1 to December 31, 2006 1. PROJECT: W-1188 CHARACTERIZING MASS AND ENERGY TRANSPORT AT DIFFERRENT
SCALES 2. ACTIVE COOPERATING AGENCIES AND PRINCIPAL LEADERS: Arizona A.W. Warrick, Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, AZ 85721 W. Rasmussen, Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, AZ 85721 P. Ferre, Department of Hydrology and Water Resources,
University of Arizona, Tucson, AZ 85721 Marcel Schaap, Dept. of Soil, Water and Environmental Science,
University of Arizona, Tucson, AZ 85721 California S. A. Bradford, George E. Brown, Jr. Salinity Lab - USDA-ARS,
Riverside, CA 92507 T. Harter, Dept. of LAWR, Hydrologic Science, University of
California Davis, CA 95616 J.W. Hopmans, Dept. of LAWR, Hydrologic Science, University of
California Davis, CA 95616 W.A. Jury, Dept. of Environmental Sciences, University of
California, Riverside, CA 92521 D.R. Nielsen, Dept. of LAWR, Hydrologic Science, University of
California Davis, CA 95616 P.J. Shouse, George E. Brown, Jr. Salinity Lab - USDA-ARS,
Riverside, CA 92507 J. ?im?nek, Dept. of Environmental Sciences, University of
California, Riverside, CA 92521 T. Skaggs, George E. Brown, Jr. Salinity Lab - USDA-ARS,
Riverside, CA 92507 M.Th. van Genuchten, George E. Brown, Jr. Salinity Lab - USDA-
ARS, Riverside, CA 92507 Z. Wang, Department of Earth and Environmental Sciences,
California State University, Fresno, CA 93720 L.Wu, Dept. of Environmental Sciences, University of California,
Riverside, CA 92521 Colorado L.R. Ahuja, USDA-ARS, Great Plains System Research Unit Fort
Collins, CO 80522 T. Green, USDA-ARS, Great Plains System Research Unit Fort
Collins, CO 80522 G. Butters, Dept. of Agronomy, Colorado State University, Ft
Collins, CO 80523 Delaware Y. Jin, Dept. of Plant and Soil Sciences, Univ. of Delaware,
Newark, DE 19716 Idaho Markus Tuller, Dept. of Plant, Soils & Environ. Sci. Univ. of Idaho,
Moscow, ID 83844
Illinois T.R. Ellsworth, University of Illinois, Urbana, IL 61801 Indiana J. Cushman, Mathematics Dept., Purdue University, W. Lafayette,
IN 47905 P.S.C. Rao, School of Civil Engineering, Purdue University, W.
Lafayette, IN 47905 Iowa R. Horton, Dept. of Agronomy, Iowa State University, Ames, IA
50011 D. Jaynes, National Soil Tilth Lab, USDA-ARS, Ames, IA 50011 Kansas G. Kluitenberg, Dept. of Agronomy, Kansas State University,
Manhattan, KS 66506 Minnesota J. Nieber, Dept. Biosystems and Agricultural Eng., University
of Minnesota,
St. Paul, MN 55108
T. Ochsner, USDA, Agricultural Research Services, St. Paul, MN
55108-6030
Montana J. M. Wraith, Land Resources and Environ. Sciences, Montana
State University, Bozeman, MT 59717-3120 Nevada T. Caldwell, Desert Research Institute, University of Nevada,
Reno, 89512 S.W. Tyler, Hydrologic Sciences Graduate Program, University of
Nevada, Reno, NV 89532 M.H. Young, Desert Research Institute, University of Nevada, Las
Vegas, NV 89119 J. Zhu, Desert Research Institute, University of Nevada, Las
Vegas, NV 89119 New Mexico J.H.M. Hendrickx, New Mexico Tech, Dept. of Geoscience,
Socorro, NM 87801 North Dakota F. Casey, Dept. of Soil Science, North Dakota State
University, Fargo, ND 58105-5638 Oregon Maria Dragila, Oregon State University, Dept. of Crop and Soil
Science, 3017 Agriculture and Life Aciences, Corvallis, Oregon
97331-7306 Tennessee J. Lee, Biosys Engin & Envir Sci., University of Tennessee,
Knoxville, TN 37996 E. Perfect, Dept. of Geo. Sciences, Univ. Tennessee Knoxville,
TN 37996-1410 Texas S.R. Evett, USDA-ARS-CPRL, P.O. Drawer 10, Bushland, TX 79012 R.C. Schwartz, USDA-ARS-CPRL, P.O. Drawer 10, Bushland, TX 79012 Utah S. Jones, Dept. of Plants, Soils & Biomet., Utah State University,
Logan, UT 84322 Washington M. Flury, Dept. of Crop & Soil Sciences, Washington State
University, Pullman, WA 99164 J. Wu, Dept. of Biological System Engineering, Washington State
University, Pullman, WA 99164 P. D. Meyer, Battelle Pacific Northwest Division, Portland, OR
97204 M. Oostrom, Battelle Pacific Northwest Division, Richland, WA
99352
M. L. Rockhold, Battelle Pacific Northwest Division Richland, WA
99352 A. L Ward, Battelle Pacific Northwest Division, Richland, WA
99352 Z. F. Zhang, Battelle Pacific Northwest Division, Richland WA
99352 Wyoming Thijs Kelleners, Dept. of Renewable Resources, University of
Wyoming, Laramie, WY 82071 CSREES R. Knighton, USDA-CSREES, Washington, DC 20250-2200 Adm. Adv. Jeff Jacobsen, Dean and Director, 202 Linfield Hall, P.O. Box
172860, College of Agriculture, Montana State University,
Bozeman, MT 59717-2860
3. PROGRESS OF WORK AND ACCOMPLISHMENTS
OBJECTIVE 1: To develop and improved understanding of the fundamental soil
physical properties and processes governing mass and energy transport, and
the biogeochemical interactions these mediate. California State University Fresno Collaborators: Zhi Wang Theoretical Re-analysis of Unstable Flow in the Upward and Horizontal
Directions and the Effect of Soil Water Repellency:
We have continued our studies on unstable flow in porous media. In an early
paper by Wang et al., (1998), theoretical derivations of fluid displacement
involving immiscible oil, water and air/gas in a porous medium by Chuoke et
al. (1959) were generalized. Twenty-four specific criteria for the onset of
unstable flow were developed. The downward water flow displacing air in the
vadose zone was predicted to be unstable (producing fingers) when the
infiltration rate I is < Vgrav -Vcap, where Vgrav is fluid velocity driven
by gravity (Vgrav = Ks|cos?|), ? is the angle between the direction of flow
and the direction of gravity, Vcap is fluid velocity driven by the
capillary forces [Vcap = (0.00015 ~ 5.7)Ks, the coefficient value varies
with soil texture ranging from coarse sand to silt clay]. The upward flow
was predicted to be unstable when the flow is too fast or if I is >
Vgrav+Vcap. The horizontal flow was predicted to be unstable if I is >
Vcap.
Our reexamination of the complex derivations and parameter definitions by
Chuoke et al. (1959) led to a new set of 24 criteria (Javaux et al., 2005).
For the upward and horizontal flow of water displacing air in soils, the
new criteria predicted unconditional stable flow (unstable only if
infiltration rate is negative), consistent with Philip's prediction.
Further more, we realized that the occurrence of unstable flow is only
related to two factors: (i) the position of the heavier fluid in the system
(either above or blow the lighter fluid), and (ii) the relative viscosity
of the driving fluid (either more or less viscous than the displaced
fluid), see the specific criteria in Table 1. Soil water repellency was not
a factor influencing the instability criteria. Tests are still needed to
verify some of the new criteria. In addition, a review paper on finger flow
studies was published in a Chinese journal SOIL (Li et al., 2006). This
will promote awareness of theoretical and experimental studies in China.
Further studies are being proposed.
Table 1. Conditions for occurrence of unstable flow, derived from Javaux et
al. (2005)
|Viscosity |Relative position of the fluids | |
|contrast | |C |
| | |horizontal/capil|
| | |lary |
| |A |B | |
| |Heavy over light |Light over heavy | |
|1. ||V|?disp| |stable |stable |
|laced | | | |
|2. ||V|>-Vcrit+Vcap ||V|> Vcrit+Vcap ||V|> Vcap |
|?driving