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Lajas Valley is plagued with salinity and waterlogging problems of the soils. Use of brackish (500 milligrams per liter) ground water for irrigation compounded the problem until an irrigation-drainage system was constructed in 1955. Lajas Valley is an alluvium-filled trough between volcanic and limestone highlands. The alluvium, mostly clay and...

Astronauts Cernan and Schmitt, of Apollo 17, landed in the Taurus-Littrow valley of the Moon on December 11, 1972. Their major objectives were: (1) to sample very ancient lunar material such as might be found in pre-Imbrian highlands as distant as possible from the Imbrium basin, and (2) to sample...

The Atlanta Regional Commission and the Earth Resources Observation Systems Data Center participated in a demonstration of the use of Landsat digital data to detect land use change in the Atlanta, Ga., area. Temporal overlays combining Landsat band-5 data from October 1972 and 1974 were made by using the General...

A legend is suggested for use with computer-generated thematic maps made from Landsat digital data that designates some of the radiometric characteristics of each thematic map unit as well as the described terrain attributes of each map unit. The relationship between spectral band and radiance for each map unit is...

The Department of Interior's EROS Data Center, managed by the U.S. Geological Survey, was established in 1972, in Sioux Falls, South Dakota, to serve as a principal dissemination facility for Landsat and other remotely Sensed data. Through the middle of 1977, the Center has supplied approximately 1.7 million copies of...

Specific growth rate of Cryptomonas ovata var. palustris Pringsheim was measured in batch culture at 14 light-temperature combinations. Both the maximum growth rate (μm) and optimum light intensity (Iopt) fit an empirical function that increases exponentially with temperature up to an optimum (Topt), then declines rapidly as temperature exceeds Topt. Incorporation of these functions into Steele's growth equation gives a...

The bibliography contains 82 citations of selected publications and technical reports.  The references deal with the application of remote sensing techniques to the collection and analysis of geographic data.  All of the citations were published between January 1968 and July 1977....

A brief study involving collection and analysis of street sweepings was undertaken to provide the U.S. Army Corps of Engineers with data on physical, chemical, and biological characteristics of dust and dirt accumulating on Portland streets. Most of the analyses selected were based on the pollutant loads predicted by the...

After acid decomposition of the sample, selenium hydride was generated by means of sodium borohydride, and the gas was swept through a resistance-heated quartz cell mounted in an atomic absorption spectrometer to determine as little as 5 ng/g selenium in 0.25 g rock sample. One-way analyses of variance of data...

Epithermal beryllium deposits in western Utah have distinctive geological and geochemical associations that provide guides to exploration for new resources of beryllium and associated metals. Beryllium deposits at Spor Mountain and the Honeycomb Hills are uniquely associated with topaz-bearing rhyolite of Late Tertiary age and are restricted to porous water-laid...

Leech parasitism of waterfowl is widespread in North America. Twenty species of ducks, geese, and swans have been infested by leeches, particularly Theromyzon rude and Placobdella ornata. Sites of attachment include the eyes, nasal passages, and body. Information is lacking on the biology and ecology of duck leeches. Their significance...

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