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Water conservation practices for sustainable dryland farming systems in the Pacific Northwest

Published online by Cambridge University Press:  30 October 2009

John E. Hammel
John E. Hammel
Affiliation:
Soil Scientist, Soil Science Division, University of Idaho, Moscow, ID 83844-2339.
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Extract

Sustainable crop production in the Pacific Northwest dry-farmed areas relies heavily on tillage and residue management systems to conserve water. Stable, sustainable yields cannot be achieved without adequate water conservation techniques. Frozen soil can reduce infiltration markedly, which decreases overwinter profile water storage and can cause severe soil erosion. Uncurbed evaporation losses throughout the year can greatly limit yields, particularly with summer fallow.

In both summer-fallowed and annually cropped regions where soil freezes frequently, fall tillage is used to increase surface macroporosity and to provide open channels to below the frost depth. This enhances infiltration throughout the winter and insures better water intake during rapid snowmelt and rainfall when the soil is frozen. Fall tillage enhances overwinter water recharge under these conditions, whereas in areas where soil freezes infrequently, it does not improve water storage efficiency.

In the dry-farmed regions receiving less than 330 mm annual precipitation, a winter wheat-fallow system is used to reduce the risk of uneconomical yields. Successful establishment of winter wheat following summer fallow is feasible only when proper management has suppressed evaporative loss. During the dry summer fallow, tillage is used to develop and maintain a soil mulch that restricts the flow of water, as both liquid and vapor. The tillage mulch effectively conserves stored soil water and maintains adequate seedzone moisture for fall establishment of winter wheat. However, the soil mulch can lead to high wind and water erosion.

In the Pacific Northwest dry-farmed region, tillage by itself is not considered a substitute for proper residue management. Crop residues following harvest are important for conserving water and controlling erosion. Under conservation programs implemented since 1985, shallow subsurface tillage systems that maintain residues on the surface have substantially reduced wind and water erosion in the region. Surface residues are effective in decreasing evaporative water loss and trapping snow during the winter, and therefore increase overwinter recharge. While surface residues are much less effective in suppressing evaporative losses in dry-farmed areas during extended dry periods, residues provide substantial control of wind and water erosion during the fallow.

Before conservation tillage systems came into use in the Pacific Northwest, water conservation frequently was achieved only through tillage. This helped to stabilize yields, but at a high cost to the soil resource. Poor use of surface residues and intensive tillage contributed to extensive wind and water erosion. Continued use of these practices would have caused yields to decline over time and required greater agrichemical inputs. To meet soil and water conservation needs, site-specific tillage and residue management systems were developed to account for the diversity and variability of soils and climate across the Pacific Northwest. Common to all these production systems is that both water conservation and effective residue management to protect the soil are required for long-term sustainable production.

Keywords

cropping systemstillagewinter wheatdry farmingresidue management
Type
Selected Papers from the U.S.-Middle East Conference on Sustainable Dryland Agriculture
Information
American Journal of Alternative Agriculture , Volume 11 , Issue 2-3 , September 1996 , pp. 58 - 63
Copyright
Copyright © Cambridge University Press 1996

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References

1.Allmaras, R.R., Ward, K., Douglas, C.L. Jr., and Ekin, L.G.. 1982. Long-term cultivation effects on hydraulic properties of a Walla Walla silt loam. Soil and Tillage Research 2:265–279.CrossRefGoogle Scholar
2.Bond, J.J., and Willis, W.O.. 1969. Soil water evaporation: Surface residue rate and placement effects. Soil Sci. Soc. Amer. Proc. 33:445–448.CrossRefGoogle Scholar
3.Bristow, K.L., Campbell, G.S., Papendick, R.I., and Elliott, L.F.. 1986. Simulation of heat and moisture transfer through a surface residue-soil system. Agricultural and Forest Meteorology 36:193–214.CrossRefGoogle Scholar
4.Cary, J.W., Papendick, R.I., and Campbell, G.S.. 1979. Water and salt movement in unsaturated frozen soil: Principles and field observations. Soil Sci. Soc. Amer. J. 43:3–8.CrossRefGoogle Scholar
5.Cochran, V.L., Papendick, R.I., and Fanning, C.D.. 1970. Early fall crop establishment to reduce winter runoff and erosion on Palouse slopes. J. Soil and Water Conservation 25:231–234.Google Scholar
6.Council for Agricultural Science and Technology. 1975. Erosion and sedimentation in the loessial region of Washington, Idaho, and Oregon. CAST Rept. No. 42. Iowa State Univ., Ames.Google Scholar
7.Elliott, L.F., Bolton, H. Jr., Stroo, H.F., and Papendick, R.I.. 1987. Some effects of residue management on rhizosphere biology. In Elliott, L.F. (ed). STEEP—Conservation Concepts and Accomplishments. Washington State Univ. Publications, Pullman, pp. 67–80.Google Scholar
8.Hammel, J.E. 1995. Long-term tillage and crop rotation effects on winter wheat production in northern Idaho. Agronomy J. 87:16–22.CrossRefGoogle Scholar
9.Hammel, J.E., Papendick, R.I., and Campbell, G.S.. 1981. Fallow tillage effects on evaporation and seedzone water content in a dry summer climate. Soil Sci. Soc. Amer. J. 45:1016–1022.CrossRefGoogle Scholar
10.Hershfield, D.M. 1974. The frequency of freeze-thaw cycles. J. Applied Meteorology 13:348–354.2.0.CO;2>CrossRefGoogle Scholar
11.Leggett, G.E. 1959. Relationships between wheat yield, available moisture, and available nitrogen in eastern Washington dryland areas. Bull. No. 609. Washington Agric. Exp. Sta., Pullman.Google Scholar
12.Leggett, G.E., Ramig, R.E., Johnson, L.C., and Massee, T.W.. 1974. Summer fallow in the Northwest. In Summer Fallow in the Western United States. Conservation Research Rept. No. 17. U.S. Dept. of Agriculture, Agric. Research Service, Washington, D.C. pp. 110–135.Google Scholar
13.Lindstrom, M.J. 1974. Wheat-fallow management practices in the low rainfall areas of the United States Pacific Northwest. In Tillage and Cultural Practices for Wheat under Low Rainfall Conditions. Proc. Second Regional Wheat Workshop, Ankara, Turkey, 05 6–11. Rockefeller Foundation, New York, N.Y.Google Scholar
14.Lindstrom, M.J., Koehler, F.E., and Papendick, R.I.. 1974. Tillage effects on fallow water storage in the eastern Washington dryland region. Agronomy J. 66:312–316.CrossRefGoogle Scholar
15.Massee, T., and McKay, H.. 1979. Improving dryland wheat production in eastern Idaho with tillage and cropping methods. Bull. No. 581. Idaho Agric. Exp. Sta., Moscow.Google Scholar
16.Massee, T.W., and Siddoway, F.H.. 1969. Fall chiseling for annual cropping of spring wheat in the Intermountain dryland region. Agronomy J. 61:177–182.CrossRefGoogle Scholar
17.Oveson, M.M., and Appleby, A.P.. 1971. Influence of tillage management in a stubble mulch fallow-winter wheat rotation with herbicide weed control. Agronomy J. 63:19–20.CrossRefGoogle Scholar
18.Papendick, R.I., and Campbell, G.S.. 1974. Wheat-fallow agriculture: Why, how, when. Proc. Second Regional Wheat Workshop, Ankara, Turkey, 05 6–11. Rockefeller Foundation, New York, N.Y.Google Scholar
19.Papendick, R.I., Lindstrom, M.J., and Cochran, V.L.. 1973. Soil mulch effects on seedbed temperature and water during fallow in eastern Washington. Soil Sci. Soc. Amer. Proc. 37:307–314.CrossRefGoogle Scholar
20.Papendick, R.I., McCool, D.K., and Krauss, H.A.. 1983. Soil conservation: Pacific Northwest. In Dregne, H.D. and Willis, W.O. (eds). Dryland Agriculture. Agronomy 23:273–290. Agronomy Soc. Amer., Madison, Wisconsin.Google Scholar
21.Papendick, R.I., and Miller, D.E.. 1977. Conservation tillage in the Pacific Northwest. J. Soil and Water Conservation 32:49–56.Google Scholar
22.Pikul, J.L. Jr., and Allmaras, R.R.. 1985. Hydraulic potential in unfrozen soil in response to diurnal freezing and thawing of the soil surface. Trans. Amer. Soc. Agric. Engineers 28:164–168.CrossRefGoogle Scholar
23.Pikul, J.L. Jr., Zuzel, J.E., and Greenwalt, R.N.. 1986. Formation of soil frost as influenced by tillage and residue management. J. Soil and Water Conservation 41:196–199.Google Scholar
24.Pikul, J.L. Jr., Boersma, L., and Rickman, R.W.. 1989. Temperature and water profiles during diurnal soil freezing and thawing: Field measurements and simulation. Soil Sci. Soc. Amer. J. 53:3–10.CrossRefGoogle Scholar
25.Pikul, J.L. Jr., Zuzel, J.E., and Wilkins, D.E.. 1992. Infiltration into frozen soil as affected by ripping. Trans. Amer. Soc. Agric. Engineers 35:83–90.CrossRefGoogle Scholar
26.Ramig, R.E. 1987. Conservation tillage systems for annually cropped wheat in the Pacific Northwest. J. Soil and Water Conservation 42:53–55.Google Scholar
27.Ramig, R.E., and Ekin, L.G.. 1984. Effect of stubble management in a wheatfallow rotation on water conservation and storage in eastern Oregon. Spec. Rep. No. 713, Oregon Agric. Exp. Sta, Corvallis.Google Scholar
28.Saxton, K.E., Kenny, J.J., Hyde, G.F., and Elliott, L.F.. 1987. Slot mulch and paraplow for conservation tillage. In Elliott, L.F. (ed). STEEP-Conservation Concepts and Accomplishments. Washington State Univ. Publications, Pullman, pp. 657–662.Google Scholar
29.Skidmore, E.L., and Woodruff, N.P.. 1968. Wind erosion forces in the United States and their use in predicting soil loss. Agric. Handbook No. 346. U.S. Dept. of Agric, Washington, D.C.Google Scholar
30.Willis, W.O., and Bond, J.J.. 1971. Soil water evaporation: Reduction by simulated tillage. Soil Sci. Soc. Amer. Proc. 35:526–529.CrossRefGoogle Scholar
31.Young, E.L., Ogg, A.G. Jr., Papendick, R.I., Thill, D.C., and Alldredge, J.R.. 1994. Tillage and weed management affects winter wheat yield in an integrated pest management system. Agronomy J. 86:147–154.CrossRefGoogle Scholar
32.Zuzel, J.E., Allmaras, R.R., and Greenwalt, R.. 1982. Runoff and soil erosion of frozen soils in northeastern Oregon. J. Soil and Water Conservation 37:351–354.Google Scholar