Contaminants used at low elevation, such as pesticides on crops, can be transported tens of kilometers and deposited in adjacent mountains in many parts of the world. Atmospherically deposited organic contaminants in the Sierra Nevada Mountains of California, USA, have exceeded some thresholds of concern, but the spatial and temporal...
This thesis reports on the growth and characterization of p-type
pseudomorphic A1GaAs /InGaAs /GaAs modulation doped field effect transistor
(MODFET) structures. A series of different p-type MODFET structures were grown
with a systematic variation of the indium mole fraction and quantum well width of
the InGaAs channel region. Extensive characterization...
Human activities may contribute to the eutrophication of surface waters by
providing nutrients to aquatic ecosystems. Phosphorus is frequently identified as a
nutrient that is limiting to most aquatic ecosystems under natural conditions. Sources of
phosphorus contributing to eutrophic conditions often include nonpoint sources that are
dispersed across the landscape....
"Crested wheatgrass, beardless wheatgrass, and big bluegrass were
seeded as overstory grasses. Streambank wheatgrass, canby bluegrass,
bulbous bluegrass, and Ladak alfalfa were seeded as companion species.
Pure and mixed stands were seeded on sagebrush-bunchgrass
range in eastern Oregon to compare yield and competitiveness. The
grasses were planted in 1956, 1957,...
One of the problems facing sheepmen on the nonirrigated pastures of western Oregon, particularly in the foothills surrounding the Willamette Valley, is the lack of succulent green pasture growth during
the late summer breeding season. If early spring lambs are being produced, ewes must be bred in August and September...
