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BSTRACT Increasing water for onsite and offsite uses can be a viable objective for management of certain western rangelands. One approach utilizes water harvesting techniques to increase surface runoff by preventing or slowing infiltration of rain. An attractive alternative, where applicable, is to replace vegetation that uses much water with plants that use less so that more water percolates through the soil to streams and ground water. Most sites are too dry to increase water yield in this way; probably less than 1 percent of the western rangelands can be managed for this purpose. However, where annual precipitation exceeds about 450 mm (18 inches) and deep-rooted shrubs can be replaced by shallow-rooted grasses, there is potential to increase streamflows and to improve forage for livestock. Little or no increase can be expected by eradication of low-density brush and pinyon-juniper woodlands. Potentials for improving water yield are reviewed and summarized by vegetation types. [ABSTRACT FROM AUTHOR]

Digital water level recorders on small, flashy streams are frequently set at 5-minute readout intervals to define fluctuations during critical storm flow periods. Consequently, during nonstorm periods far more data points are punched on the recorder tapes than are needed to define the long-term hydrograph. A two-step reduction process eliminates more than 95% of the original 105,000 data points per year of record. The first reduction is obtained by translating to IBM cards only every twelfth (hourly) head value punched on the tape during nonstorm periods. Storm periods are translated at 5-minute intervals. A computer reduction step on both hourly and 5-minute data then systematically rejects head values not essential to hydrograph definition. Rejection is based on differences in elevation and slope between successive head values. Computer output consists of cards and a listing of the reduced data. [ABSTRACT FROM AUTHOR]

Water yield has increased substantially on two small chaparral watersheds in central Arizona following brush control and conversion to grass. Winter precipitation is the major source of water yield. Summer rains begin in July and normally account for about one-fourth of the annual precipitation but generally have little effect on streamflow. When annual precipitation is less than 16 inches, increase in water yield resulting from treatment is likely to be less than 2 inches. However, the efficiency of the conversion for producing extra water improves with rainfall, at least up to 34 inches. At this amount of annual precipitation, the increase in flow may reach 12 inches or more, depending on seasonal distribution of the rain. [ABSTRACT FROM AUTHOR]

It seems logical that the American student of Spanish should now be taught the seseo, since his oral and aural contact with the language will probably be with the Spanish-American pronunciation, and since even in the study of the literature of Spain the seseo will not be a serious hindrance. [ABSTRACT FROM AUTHOR]