Consumption of bottled water is increasing worldwide. Prior research shows many consumers believe bottled water is convenient and has better taste than tap water, despite reports of a number of water quality incidents with bottled water. The authors explore the demographic and social factors associated with bottled water users in the U.S. and the relationship between bottled water use and perceptions of the quality of local water supply. They find that U.S. consumers are more likely to report bottled water as their primary drinking water source when they perceive that drinking water is not safe. Furthermore, those who give lower ratings to the quality of their ground water are more likely to regularly purchase bottle water for drinking and use bottle water as their primary drinking water source.
Heavy application of ammonium-based N fertilizers on cereal crops has resulted in the acidification of soils in northern Idaho. The objective of this 5-yr study initiated in 1981 was to determine the effect of soil pH on the yield of lentil (Lens culinaris, cv. Tekoa and Chilean), spring pea (Pisum sativum, cv. Columbia and Alaska), winter wheat (Triticum aestivum, cv. Daws, Hill 81, and Stephens), and spring barley (Hordeum vulgare, cv. Advance and Steptoe). Data were compiled from 39 field studies conducted on Mollisols and Alfisols to produce mathematical models to describe soil pH-yield relationships. Linear-plateau regression models consisting of intersecting straight lines were fitted to percent maximum yield data for each crop or crop cultivar. The point where the two lines intersected was called the minimum acceptable pH for maximum yield. Lentil and pea were least tolerant to acid conditions, with minimum acceptable pH values required for maximum yields of 5.65 and 5.52, respectively. Cereals were more tolerant, with a minimum acceptable pH value of 5.23 for spring barley. The three winter wheat cultivars reacted differently to soil pH, as Daws, Hill 81, and Stephens had minimum acceptable pH values of5.19, 5.37, respectively. Even though Hill 81 did not have the lowest minimum acceptable pH value, it was considered the most acid-tolerant winter wheat cultivar because the slope of the line describing the relationship between pH and yield in the limiting region was less than those of the other two cultivars.
Studies to increase profitability and N use efficiency in winter wheat (Triticum aestivum L.) production are needed to develop more sustainable agricultural systems in the 480‐ to 650‐mm precipitation zone of northern Idaho and eastern Washington. Field experiments were conducted on Latahco silt loam (fine‐silty, mixed, frigid Argiaquic Xeric Argialboll) soils east of Moscow, ID, during the 1982–1983, 1983–1984, 1985–1986 and 1986–1987 growing seasons. Fifteen different N placement‐source‐application timing treatments were arranged in a randomized complete block design with five replications. Fertilizer placements were (i) surface broadcast, (ii) band 50 mm below the seed, and (iii) combinations of surface broadcast and banded below the seed placements. Times of application treatments were (i) fall, (ii) spring, and (iii) various fall‐spring splits. All treatments were evaluated with two N sources: NH4NO3 (AN) and urea (U). Parameters evaluated were (i) winter wheat stand counts, (ii) early‐season plant biomass, (iii) grain yield, and (iv) apparent N use efficiency (NUE). Placement, N source and time of application had minimal impacts on winter wheat stand counts and early season biomass production. Both winter wheat grain yield and apparent NUE were greatest when N applications were split between fall and spring. Splitting time of N application resulted in apparent NUE of 58 to 61%, compared with 52 to 55% and 51 to 53% for fall only and spring only N applications, respectively. Grain yield and apparent NUE differences attributable to N source and N placement were not significant. Based on this study, ideal N management in the 480‐ to 650‐mm precipitation zone would utilize AN, U, or comparable N sources and split N applications where as little as 25% of the N is banded below the seed or surface broadcast in the fall, with the remainder applied as a spring topdress prior to Zadoks growth stage 24. This proposed management will improve both profitability and water quality by increasing both grain yield and N use efficiency when compared with systems currently employed.
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