From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona

From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona / Strip mining leaves behind spoils to be recontoured to maximize the benefit of livestock production on the rehabilitated land. This paper designs watersheds to achieve a balance between two main range livestock requirements, forage and stock water by way of grading and furrowing man-made slopes. The three design attributes, surface configuration, surface treatment, and range management policy are optimized with respect to maximal profit accounting for natural uncertainties in 3 variables, viz., time interval between storm arrivals, precipitation per storm event, and duration of the storm event. Runoff and sedimentation are modeled on an event basis as functions of said random variables. The stock water reservoir at the bottom of the watershed is dredged periodically. The stochastic model is applied to the Black Mesa in Northern Arizona which is in the process of being strip-mined for coal.

From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona

From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona / Osmosis occurs when two solutions of differing osmolar concentrations are separated by a membrane permeable to the solvent but not (or nearly not) to the solutes. This paper derives the relationship between the kinetics and design parameters of systems designed for the purpose of applying this process to problems such as agricultural water reclamation, dehydration of solutions and the production of potable nutrient solutions from sea water. Three mathematical models that include increasingly complex fundamental process assumptions are presented. In all cases the fundamental mechanical device is assumed to be a continuous flow extractor that incorporates a semipermeable membrane.

From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona / Solar powered pumping is technically feasible. However, solar energy intensity is variable and its collection requires high capital investment. Present production methods might require modification for most economic use of solar energy. Various irrigation and pumping practices are examined to determine those most compatible with use of solar power. The tentative conclusion of the study is that solar energy usage is most economical for driving pumps only during sunlight hours and where pumping requirements are uniform throughout the year. Solar energy is a more costly source of pumping power than electricity or natural gas.

From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona

From the Proceedings of the 1977 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 15-16, 1977, Las Vegas, Nevada / In contrast to three ephemeral streams in the vicinity, Tony Bear Creek, a small perennial stream in the White Mountains of Arizona, showed strong relationships among parameters of hydraulic geometry. Distances between gravel bars and log steps showed an inverse relationship with gradient (r² = 0.95). Shape factor and width-depth ratio increased upstream (r² = 0.98 and 0.90, respectively), indicating depth decrease toward the headwaters. The longitudinal profile is concave, and small, infrequent channel bars suggest that sediment movement is small. In contrast to the ephemeral streams, Tony Bear Creek is thus judged to be in dynamic equilibrium. Proportion of log steps to total steps (gravel bars plus logs) was much smaller in Tony Bear Creek (about 16 %) than in five other mountain streams (about 50 %). While all other streams ran through dense forests, only 60% of Tony Bear Creek was in forest, of which 13% had been selectively cut. Thus, forest density determined the proportion of logs incorporated into the stream hydraulic system, which in turn affects bedload movement.

From the Proceedings of the 1977 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 15-16, 1977, Las Vegas, Nevada / A 3-year study was conducted using tilted, vertical, directional, and recording rain gages (52 in all) to evaluate rainfall distribution on the Three Bar experimental watersheds in central Arizona. The tilted gages did not improve the determination of mean areal precipitation on the small watersheds because about as many tilted gages caught less rain as caught more. Although rugged and steep, the local topography exerted only minor effects on rainfall distribution compared to the major influence exerted by the Mazatzal Mountains to the windward (southwest). Forty-nine percent of wind travel was from the southwest quarter and wind averaged 4.4 mph when rain was actually falling. Wind exceeded 10 mph 9 percent of the time and 15 mph 0.4 percent of the time. Mean annual precipitation on the 600-acre study area ranged from 30 inches at 5,000 feet elevation to 22 inches at 3,400 feet (5 inches per 1,000 feet). Results of this study indicate that precipitation averages about 36 inches at 6,200 feet elevation along the Mazatzal crest near Four Peaks, about 6 inches more than published data show for the site.

From the Proceedings of the 1977 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 15-16, 1977, Las Vegas, Nevada

From the Proceedings of the 1977 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 15-16, 1977, Las Vegas, Nevada / Ratios of oxygen-18 to oxygen-16 in cellulose of dated rings from trees grown in nature and from plants grown in controlled environments have significance for retrieving information about the environment in which they grew. Phaseolus vulgaris was grown under varying conditions of controlled temperature, humidity and ¹⁸O/ ¹⁶O of irrigation water. The ¹⁸O/ ¹⁶O in plant tissue responds mostly to different environmental relative humidity; plant tissue grown under conditions of low relative humidity produce tissue relatively high in oxygen-18. Reasons for this response are not clear to us, but the relationship may prove a useful complement to established dendroclimatologic techniques.