![]() |
![]() |
![]() |
---|
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
---|
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
ENWATBAL.BAS is a mechanistic one-dimensional computer program written in Microsoft compiled BASIC which separately computes evaporation from the soil and plant canopy. It has been used successfully to simulate E from bare soil as well as E and T for corn, sorghum, wheat and cotton; and has been used to estimate the reduction in evaporation loss due to using subsurface as opposed to surface drip irrigation. The model assumes a single layer plant canopy (big leaf model) but can accept data for up to 9 soil horizons and any reasonable number of soil layers (i.e. finite difference nodes). ENWATBAL.BAS was derived from the program ENWATBAL published by van Bavel and Lascano. See our paper titled, "ENWATBAL.BAS: A mechanistic evapo-transpiration model written in compiled BASIC" (Evett and Lascano, 1993) for a list of references to ENWATBAL and precursor models such as WATBAL and CONSERVB. The computer source code is heavily commented so that variables and their units are identified and explanations of each significant section of code are given. Currently the best documentation of the model is Van Bavel and Lascano (1987). ENWATBAL.BAS is available from Steven R. Evett, USDA-ARS, Conservation and Production Research Laboratory, P.O. Drawer 10, Bushland, TX 79012 (Tel. 806-356-5775, Internet: srevett@cprl.ars.usda.gov ) or click on this link ENWATBLZ.EXE to download a self-extracting file containing source code, example data files and documentation.
Evett, S.R., T.A. Howell, A.D. Schneider, and J.A. Tolk. 1995. Crop coefficient based evapotranspiration estimates compared with mechanistic model results. In Proc. First Internatl. Conf. Water Resour. Engineer., San Antonio, TX, Aug. 14-18. pp.
Click to download manuscript in Adobe format(84 kb).
Evett, S.R., T.A. Howell, and A.D. Schneider. 1995. Energy and water balances for surface and subsurface drip irrigated corn. In Proc. Fifth Internatl. Microirrigation Congress, Orlando, Florida, April 2-6, 1995. pp. 135-140.
Click to download manuscript in Adobe format (97 kb).
Evett, S.R., T.A. Howell, A.D. Schneider, K.S. Copeland, and D.A. Dusek. 1994. Energy and water balance modeling of winter wheat. Presented at the 1994 International Summer Meeting, Amer. Soc. Agric. Engr., Paper No. 942022, ASAE, 2950 Niles Rd., St. Joseph, MI 49085-9639.
Click to download manuscript in Adobe format (232 kb).
Evett, S.R., and R.J. Lascano. 1993. ENWATBAL.BAS: A mechanistic evapo-transpiration model written in compiled BASIC. Agron. J. 85(3):763-772.
Click to download manuscript in Adobe format (237 kb).
Evett, S.R., A.D. Matthias, and A.W. Warrick. 1994. Energy Balance Model of Spatially Variable Evaporation from Bare Soil. Soil Sci. Soc. Am. J. 58(6):1604-1611
Click to download manuscript in Adobe format (205 kb).
Howell, T.A., J.L. Steiner, S.R. Evett, A.D. Schneider, K.S. Copeland, D.A. Dusek, and A. Tunick. 1993. Radiation balance and soil water evaporation of bare Pullman clay loam. In Management of Irrigation and Drainage Systems. Proc. Symp. July 21-23, 1993, Park City, Utah. Amer. Soc. Civil. Engr.
Evett, S.R., J.L. Steiner, T.A. Howell, and A.A. Durar. 1992. Water and energy balance of bare soil: Comparison of simulation models and weighing lysimeter data. Agronomy Abstracts, p. 15.
Evett, S.R., T.A. Howell, J.L. Steiner, and J.A. Tolk. 1991. Measured and modeled soil and plant evaporation. Agronomy Abstracts, p. 16.
Evett, S.R., and R.J. Lascano. 1990. ENWATBAL - A mechanistic evapotranspiration model written in compiled BASIC. Agronomy Abstracts, p. 16.
Van Bavel, C.H.M., and R.J. Lascano. 1987. ENWATBAL: A numerical method to compute the water loss from a crop by transpiration and evaporation. Texas Agricultural Experiment Station, Texas A&M Univ., College Station, TX 77843-2474, 75 pp. plus 3 appended articles.