10,603 research outputs found
Heat and Mass Transfer in Cold Regions Soils
The work upon which this report is based was made possible by a cooperative
aid agreement between the U.S. Forest Service, Institute of Northern
Forestry, Fairbanks, Alaska, and the Institute of Water Resources, University
of Alaska. Contributions to this study were also made by the University of
California at Davis and Ohio State University. The collection of winter
data on pore pressures was made possible by a separate grant by the Office
of Water Research and Technology (project A-053 ALAS)
Hydrologic Properties of Subarctic Organic Soils
Completion Report
for
U. S. Forest Service
Institute of Northern Forestry
Cooperative Agreement No. 16 USC 581; 581a-581iThe need for understanding the natural system and how it responds
to various stresses is important; this is especially so in an environment
where the climate not only sustains permafrost, but develops
massive seasonal frost as well. Consequently, the role of the shallow
surface organic layer is also quite important. Since a slight change in
the soil thermal regime may bring about a phase change in the water or
ice, therefore, the system response to surface alterations such as
burning can be quite severe. The need for a better understanding of the
behavior and properties of the organic layer is, therefore, accentuated.
The central theme of this study was the examination of the hydrologic
and hydraulic properties of subarctic organic soils. Summarized
in this paper are the results of three aspects of subarctic organic soil
examinations conducted during the duration of the project. First, a
field site was set up in Washington Creek with the major emphasis on
measuring numerous variables of that soil system during the summer. The
greatest variations in moisture content occur in the thick organic soils
that exist at this site. Our major emphasis was to study the soil
moisture levels in these soils. This topic is covered in the first
major section, including associated laboratory studies. Those laboratory
studies include investigations of several hydraulic and hydrologic
properties of taiga organic and mineral soils. Second, some field data
on organic moisture levels was collected at the site of prescribed burns
in Washington Creek to ascertain the sustainability of fires as a function
of moisture levels. This portion of the study is described under the
second major heading. The last element of this study was a continued
application of the two-dimensional flow model that was developed in an
earlier study funded by the U. S. Forest Service, Institute of Northern
Forestry, and reported by Kane, Luthin, and Taylor (1975a).
Many of the results and concepts gathered in the field work were
integrated into the modeling effort, which is aimed at producing better
estimates of the hydrologic effects of surface disturbances in the black
spruce taiga subarctic ecosystem. This knowledge should also contribute
to better fire management decisions of the same system.The work upon which this report is based was made possible by a
cooperative aid agreement funded by the U. S. Forest Service, Institute
of Northern Forestry, Fairbanks, Alaska. Contribution to this study was
also made by Ohio State University
Small-X Quarks at HERA Predict the Ultra High Energy Neutrino-Nucleon Cross Section
New structure function data at small Bjorken from HERA are used along
with next-to-leading order QCD evolution to predict a cross section for
charged-current interactions of ultrahigh energy neutrinos with nucleons. This
new result is over twice the size of previous estimates and has important
implications for cosmic ray experiments now underway as well as for KM3 arrays
(cubic kilometer-scale neutrino telescopes) now in the planning stages.Comment: KITCS94-9-1, 9 pages (REVTeX) plus 3 postscript figures all uuencode
Deep reef fish surveys by submersible on Alderdice, McGrail, and Sonnier Banks in the Northwestern Gulf of Mexico
Submersible surveys at numerous reefs and banks in the northwestern Gulf of Mexico (NWGOM) were conducted as part of the Sustainable Seas Expedition (SSE) during July/August
2002 to identify reef fish communities, characterize benthic habitats, and identify deep coral reef ecosystems. To identify the spatial extent of hard bottom reef
communities, the Flower Garden Banks National Marine Sanctuary (FGBNMS) and the U.S. Geological Survey (USGS)
mapped approximately 2000 km2 of the Northwestern Gulf of Mexico (NWGOM) continental shelf during June 2002 with
high-resolution multibeam bathymetry. Previous investigations conducted on the features of interest (with the exceptions of East and West Flower Garden and Sonnier
Banks, accessible by SCUBA) had not been conducted since the 1970s and 1980s, and did not have the use of high-resolution maps to target survey sites. The base maps were instrumental in navigating submersibles to specific features at each study site during the Sustainable Seas
Expedition (SSE)—a submersible effort culminating from a partnership between the National Atmospheric and Oceanic
Administration (NOAA) and the National Geographic Society (NGS). We report the initial findings of our submersible surveys, including habitat and reef fish diversity at
McGrail, Alderdice, and Sonnier Banks. A total of 120 species and 40,724 individuals were identified from video surveys at the three banks. Planktivorous fishes constituted over 87% by number for the three banks, ranging from 81.4% at Sonnier Banks to 94.3% at Alderdice Bank,
indicating a direct link to pelagic prey communities, particularly in the deep reef zones. High numbers of groupers, snappers, jacks, and other fishery species
were observed on all three features. These sites were nominated as Habitat Areas of Particular Concern (HAPC) by
the Gulf of Mexico Fishery Council in March 2004. Data obtained during this project will contribute to benthic habitat characterization and assessment of the associated
fish communities through future SCUBA, ROV, and submersible missions, and allow comparisons to other deep reef
ecosystems found throughout the Gulf of Mexico and western Atlantic Ocean
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