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At least 37 records · Page 2Linked to original sources
USGS1980

A variable circular-plot method for estimated bird numbers

A bird census method is presented that is designed for tall, structurally complex vegetation types, and rugged terrain. With this method the observer counts all birds seen or heard around a station, and estimates the horizontal distance from the station to each bird. Count periods at stations vary according to the avian community and structural complexity of the vegetation. The density of each species is determined by inspecting a histogram of the number of individuals per unit area in concentric bands of predetermined widths about the stations, choosing the band (with outside radius x) where the density begins to decline, and summing the number of individuals counted within the circle of radius x and dividing by the area (Bx2). Although all observations beyond radius x are rejected with this procedure, coefficients of maximum distance.

Condor↗
USGS2018

Information to prevent human exposure to disease agents associated with wildlife—U.S. Geological Survey circulars on zoonotic disease

The U.S. Geological Survey in collaboration with the U.S. Fish and Wildlife Service and others have published reports with information about geographic distribution, specific pathogens, disease ecology, and strategies to avoid exposure and infection for a selection of zoonotic diseases. Zoonotic diseases are diseases that can be passed from animals to humans, such as rabies and plague. This summary factsheet highlights the reports on plague, bat rabies, and raccoon roundworm with links to all seven zoonotic diseases covered in this series.

Fact Sheet↗
USGS1983

Selected data for low-temperature (less than 90 degrees C) geothermal systems in the United States; reference data for U.S. Geological Survey Circular 892

Supporting data are presented for the 1982 low-temperature geothermal resource assessment of the United States. Data are presented for 2072 geothermal sites which are representative of 1168 low-temperature geothermal systems identified in 26 States. The low-temperature geothermal systems consist of 978 isolated hydrothermal-convection systems, 148 delineated-area hydrothermal-convection systems, and 42 delineated-area conduction-dominated systems. The basic data and estimates of reservoir conditions are presented for each geothermal system, and energy estimates are given for the accessible resource base, resource, and beneficial heat for each isolated system.

Open-File Report↗
USGS1980

Circular current loops, magnetic dipoles and spherical harmonic analysis.

Spherical harmonic analysis (SHA) is the most used method of describing the Earth's magnetic field, even though spherical harmonic coefficients (SHC) almost completely defy interpretation in terms of real sources. Some moderately successful efforts have been made to represent the field in terms of dipoles placed in the core in an effort to have the model come closer to representing real sources. Dipole sources are only a first approximation to the real sources which are thought to be a very complicated network of electrical currents in the core of the Earth. -Author

Journal of Geomagnetism & Geoelectricity↗
USGS1990

Geohydrology of the near-surface unsaturated zone adjacent to the disposal site for low-level radioactive waste near Beatty, Nevada: A section in Safe disposal of radionuclides in low-level radioactive-waste repository sites; Low-level radioactive-waste disposal workshop, U.S. Geological Survey, July 11-16, 1987, Big Bear Lake, Calif., Proceedings (Circular 1036)

Shallow-land burial in arid areas is considered the best method for isolating low-level radioactive waste from the environment (Nichols and Goode, this report; Mercer and others, 1983). A major threat to waste isolation in shallow trenches is ground-water percolation. Repository sites in arid areas are believed to minimize the risk of ground-water contamination because such sites receive minimal precipitation and are underlain by thick unsaturated zones. Unfortunately, few data are available on rates of water percolation in an arid environment.

Nevada↗