Browse on keywords: erosion WA P
Search results on 10/20/18
3288. Pan, W.L. and A.G. Hopkins. 1991. Plant development, and N and P use of winter barley. I Evidence of water stress-induced P deficiency in an eroded toposequence.. Plant Soil 135:9-19.
Winter barley was grown at three landscape positions of a representative toposequence in the Palouse region to identify soil factors which limit plant development and nutrient use efficiency in the eroded slope positions. Subsurface P was severely deficient at eroded ridgetop and sideslope positions. Drying of surface soil during the growing season prevented roots from using much surface applied P. This moisture stress-induced P deficiency suggests that deep placement of P is needed to build subsoil P levels for enhanced productivity on these eroded sites.
765. Benson, V., W. Goldstein, D. Young, J. Williams, and C. Jones. 1988. Impacts of cropping practices on nitrogen use and movement.. Proc. Intl. Conf. on Dryland Farming.
Conventional and PALS practices were used as inputs for the EPIC model to simulate the effects of the systems over 108 years on an Athena soil. Total erosion over 108 yr under PALS was 40% less than the conventional system. Nitrogen loss through water was 25% less under PALS than conventional. Percolation loss of N was zero for both systems. Neither system had significant increase or decrease in yields after 108 yr of erosion.
1819. Elliott, L.F. (ed.). 1987. STEEP - Conservation concepts and accomplishments.. Washington State Univ. Publ., 662pp..
A compilation of 48 papers covering: tillage and plant maagement; erosion and runoff predictions; plant design; pest management; socio-economic; integrated systems; technology transfer for cropping systems; 22 technical notes. T: many
1219. Caplan, A.J.. 1986. Cost return and relative soil loss comparisons of alternative tillage systems.. MS Thesis.
Minimum tillage is less expensive than conventional. No-till is most expensive due to high chemical inputs. In the low precipitation zone, minimum till was 1.19 times less expenxive than conventional. Annual peas/wheat in high precip. zone was 1.5 times less expensive with min-till than conventional.
1369. Cochran, V.L., R.I. Papendick and C.D. Fanning. 1970. Early fall crop establishment to reduce winter runoff and erosion.. J. Soil Water Conservation, 25(6):231-234.
An experiment was done to measure differences in seeding dates and double disk vs. deep furrow planting on erosion and yield of wheat. The study found that earlier (Sept.) seeded wheat planted at wider spacings (16 in.) with a deep furrow drill had higher yields and less erosion that conventional double disk October seeded wheat. T: Influence of seeding method (deep furrow vs. double disk) on wheat yield.
2163. George, G.O.. 1981. Best management practices (BMP) demonstration and evaluation project.. OR Agr. Expt. Sta. Special Report #623, p.43-44.
In 1979, the program was expanded to evaluate recognized Best Management Practices (BMP's) and demonstrate their impacts on water quality. All terraces will reduce erosion and sediment and improve water quality, but may not bring soil losses within tolerance limits. Stubble mulch and conservation tillage will reduce water pollution by keeping erosion from initiating during low rainfall or runoff conditions. Conservation practices are more effective in keeping soil losses within established tolerance limits than terraces. They are not as effective in removing sediment pollutants as the terrace once sediment is picked up by the runoff water. Grassed waterways and stream buffer strips reduce sediment delivery to streams, but have little or no impact on in-field erosion. Where combinations of practices were utilized and measurements were made there was decidedly less erosion and, therefore, less sediment for water pollution.
2635. Hoag, D., D. Taylor, and D. Young. 1984. Do acreage diversion programs encourage farming erodible land? A Palouse case study.. J. Soil Water Cons. 39:138-143.
Analysis shows that farming erodible class IVe land in the high rainfall zone of the Palouse generally covers variable costs of production even in the absence of USDA acreage reduction programs. The economic disincentives of USDA programs served to prevent conversion of these lands to permanent grass cover. Even under the CRP, farmers will continue to profit from farming this class of land.
2735. Horner, G.M., M.M. Oveson, G.O. Baker, and W.W. Pawson.. 1960. Effect of cropping practices on yield, soil organic matter and erosion in the Pacific Northwest wheat region.. PNW Technical bulletin 1; USDA-ARS and Ag. Expt. Sta.'s of ID, OR, WA.
Summary of soil management experiments conducted over 40 yrs at six experiment stations. Covers: crop rotation, fertilization, and use of organic material. Some results: sweetclover and alfalfa were more effective than other legumes in increasing wheat yield. Yields of wheat were markedly affected by the sequences of cropping. Return of straw to soil decreased yields slightly under low N conditions. Organic and mineral N had no effect on yields in low precip. zones. Also covers runoff and erosion. T: many, eg.: effect of crop rotations on crop yield; crop yield as affected by grass/clover; effect of OM on wheat yield.
3210. Bhatti, A.U.. 1990. Spatial variability and geostatistical estimation of soil properties and wheat yield on eroded lands in the Palouse region.. Chpt. 3, PhD. Dissertation, Dept. of Agronomy & Soils, Washington State Univ., Pullman, WA 99164.
Spatial variability of organic matter, soil P, and wheat yields was studied using classical statistical and geostatistical approaches on two commercial wheat farms in the Palouse region of eastern Washington. Geostatistics indicated strong spatial relationship of soil properties and wheat yields with a range of influence of 50-200 m. The two sites differed greatly in spatial patterns due primarily to differences in topography and the extent of erosion and topsoil loss. As a consequence of topsoil loss and reductions in organic matter, it was demonstrated that spatial patterns in yield and soil phosphorus were strongly correlated with organic matter patterns. Remote sensing of soil organic matter and the use of geostatistics offers a way to quickly assess spatial patterns in grain yield and available phosphorus.
3220. Bhatti, A.U.. 1990. A comparison of criteria for dividing eroded wheat fields into different management zones.. Chpt. 2 PhD. Dissertation, Dept. of Agronomy & Soils, Washington State univ., Pullman, WA 99164.
The study examined possible criteria for dividing dryland grain fields into management units for variable fertilizer (and other input) management. Criteria evaluated included fertility status, organic matter content, available water content, soil pH, erosion class, and wheat yield. Erosion class and soil pH were not satisfactory, but the other criteria were acceptable since they all allowed division of the field into three zones with significantly different grain yields as well as different nitrogen fertilizer rates (ranging from 0 to 90 kg N/ha). For each criterion, the field-averaged rates of recommended N were about 35 kg/ha, which is much lower than the grower's typical uniform application of 73 kg N/ha. Generally, the lowest N rates were recommended for eroded hilltops where productivity was low. The two best criteria appeared to be soil organic matter content and grain yield, as they accounted for P deficiency in the eroded zones. Remote sensing can now assess spatial patterns of organic matter on bare soil, thus providing a quick and easy way to delineate production zones.