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J. L. Peard

Publications and source records attributed to J. L. Peard.

7 recordsLinked to original sources
USGS1984

Chemical analyses of soils and other surficial materials, Alaska

Introduction: The favorable response to the reports on the geochemistry of unconsolidated surficial materials of the conterminous United States (informally called the '50-mile geochemical survey,' Shacklette and others, 1971a, 1971b, 1973, and 1974) led us, in 1975, to initiate a somewhat similar survey of Alaska. The principal objective of studies of this type is to establish estimates of the abundance of elements in soils and other surficial materials. Such information is useful in the evaluation of geochemical data for (1) mineral resources, (2) environmental appraisals, and (3) the definition of broad-scale geochemical patterns. For about six years this effort progressed slowly on a non-funded, time-available basis. During fiscal years 1982 and 1983, however, some funds were made available through the USGS Energy Lands and Alaska Mineral Surveys programs which allowed for the completion of the field-work phase of the project. The sampling plan was kept simple because, as with the 50-mile study, the acquisition of samples depended on the voluntary cooperation of field personnel (only about 40 percent of the total number of samples was obtained by the authors).

Open-File Report↗
USGS1983

Distribution of corticolous noncrustose lichens on trunks of Rocky Mountain junipers in Boulder County, Colorado.

Nineteen species of noncrustose lichens were found on Juniperus scopulorum bark; 3 species had relatively high cover and frequency values and were characterized as typical lichens of Rocky Mountain junipers: Xanthoria fallax, Phaeophyscia hirsuta and Physcia caesia. Total cover per tree was low (4%) and most species preferred the N and E sides of trunk bases. These distributional trends may reflect gradients of exposure to wind, insolation, and rate of bark exfoliation. -Author Juniperus scopulorum Phaeophyscia hirsuta Physcia caesia Xanthoria fallax.

Colorado↗