Browse on keywords: moisture OR tillage
Search results on 02/18/19
3900. Lindstrom, M.J., F.E. Koehler, and R.I. Papendick. 1974. Tillage effects on fallow water storage in the eastern Washington dryland region.. Agron. J. 66:312-316.
206. Allmaras, R.R.. 1967. Soil water storage as affected by infiltration and evaporation in relation to tillage-induced soil structure. p. 37-43.. IN: Tillage for Greater Crop Production (Conf. Proc.).
Soil water storage as affected by infiltration and evaporation in relation to tillage-induced soil structure.
5253. Pikul, J.L. Jr., J.F. Zuzel and R.N. Greenwalt. 1988. Tillage impacts on water infiltration.. OR Agr. Expt. Sta. Special Report 827, p.46.
5566. Ramig, R.E. and L.G. Ekin. 1976. Conservation tillage effects on water storage and crop yield in Walla Walla and Ritzville soils.. OR Agr. Expt. Sta. Special Report 459, p.15.
5585. Ramig, R.E. and L.G. Ekin. 1987. Fallow systems for semiarid eastern Oregon and Washington.. OR Agr. Expt. Sta. Special Report 797, p.34.
5593. Ramig, R.E. and L.G. Ekin. 1978. Soil water storage as influenced by tillage and crop residue management.. OR Agr. Expt. Sta. 1978 Progress Report..
6929. Unger, P.W., C.W. Lindwall, D.W. Anderson, and C.A. Campbell. 1989. Mechanized farming systems for sustaining crop production and maintaining soil quality in semiarid regions.. unpublished manuscript, USDA-ARS, Conservation and Production Research Lab, Bushland, TX 79012.
This review paper presents research results primarily from the Northern Plains, Southern Plains, Pacific Northwest, and Australia, addressing issues of soil quality and organic matter, erosion, water storage and utilization, and how these are affected by tillage choices, crop rotations, and other management aspects. Cultivation of semiarid soils generally leads to soil organic matter (SOM) losses of 40-60%, with most loss in the first 20 years. The active fraction of SOM will change faster than the total SOM. The fraction of N that is readily mineralizable decreased more quickly than total N, indicating a reduction in the nutrient-supplying power of the soil over time. Cultivation decreases the proportion of soil aggregates >1 mm. Dry-stable aggregates >0.84 mm are needed to prevent wind erosion. In the Northern Plains, about 60% of the precipitation falls in the May to August growing season. The crop-fallow system here is relatively inefficient at water storage, storing only 20-25% of the precipitation during the fallow period. Crop stubble is crucial to snow trapping and moisture retention. Alternating strips about 5 m. wide of tall and short stubble increased snow depth and density and resulted in 30% more water storage compared to a uniform medium-height stubble. No-till improved yields in many cases by increasing stored moisture, but suitable herbicides are necessary for weed control. Flex cropping in Montana was the most efficient system for using moisture. In the Central Plains, increased evapotranspiration makes ample surface residue very effective. Yields for wheat in a fallow system were more than double those for continuous wheat, making the fallow system more economic. In the Pacific Northwest, major losses result from runoff and from evaporation, due to capillary action in undisturbed surface soils. Water storage efficiencies were 50-75% during the first winter, and 10-50% during the second winter at Pendleton, OR. Surface residues resulted in greater evaporative losses during the summer. To control erosion, innovations such as the slot mulch system, the paraplow, and basin pitters (dammer-diker) have been used. The paper has an excellent list of references on dryland cropping.
10245. Ramig, R.E. and L.G. Ekin. 1991. When do we store water with fallow?. 1991 Columbia Basin Agricultural Research, Special Report 879, OR Agr. Expt. Sta., Corvallis.
Water storage was monitored at Pendleton (16" precip.) and Moro (11" precip.), Oregon from 1978-1984. Storage percentages for the fallow winter, fallow summer, and crop winter were 75, -19, and 54 %, respectively. Significantly less water was stored during the fallow winter in both rainfall zones where the wheat stubble had been burned in the fall. Differences in water conservation and storage among other treatments (spring plow, fall flail, fall disk, and spring sweep) were not significant at both locations. Total water storage for the 18-month crop-fallow cycle was 37 % at Moro and 33% at Pendleton. The best opportunity to improve water conservation and storage in this climate appears to be during the crop winter when only 40-54% of the precipitation was stored.