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1	A Diffuse Spectral Reflectance Library of Clay Minerals and Clay Mixtures within the VIS/NIR Bands Vlack, Yvette A. 18 November 2008 (has links) No description available. Geology Soil Sciences DSR diffuse spectral reflectance clays clay minerals clay mixtures spectral library PCA priniciple component ananlysis stepwise linear regression SLR regression models MNK3 Millbrig iron-bearing minerals ASD Analytical Spectral Device
2	Time-Related Changes in Water Quality of Stock Tanks of Southeastern Arizona Wallace, D. E., Schreiber, H. A. 20 April 1974 (has links) From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / This study attempts to determine the water quality changes in stock tanks and what factors are instrumental in the changes, and to assess the effects of the changes. Algal growth was the most prominent change taking place in the tanks with time. Little change in the water chemistry was noted until just before the tanks dried up. As algae died, ions tied up by the algae were released to the water, causing an increase in concentration of many of the nutrients. In order to determine the impact of various factors on algal growth, the data from eight stock tanks were analyzed by stepwise linear regression. Although 20 variables were used in the complete analysis, six variables were associated with 56.3 percent of the variance: time (since first sampling), total n, potassium, pH, inflow (recharge to the tanks), and hco3 concentration. Time and total n explained 51.3 percent of the variance, and potassium increased the variance to 52.8 percent. The pH reversed the relative positions of time and total n, with total n becoming dominant. The last two factors, inflow and hco3 were negative (resulting in a decrease in algal population) and increased the coefficient of variance to 56.3 percent. Hydrology -- Arizona. Water resources development -- Arizona. Hydrology -- Southwestern states. Stock water Ponds Algae Water chemistry Regression analysis Water quality Arizona Farm ponds Water harvesting Standing waters Water storage Nutrients Hydrogen ion concentration Inorganic compounds Water analysis Variability Time Nitrogen compounds Potassium Inflow Bicarbonates Algal growth Stock tanks Stepwise linear regression

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A Diffuse Spectral Reflectance Library of Clay Minerals and Clay Mixtures within the VIS/NIR Bands

Time-Related Changes in Water Quality of Stock Tanks of Southeastern Arizona