Treesearch

Water use in the United States to the year 2040 is estimated by extending past trends in basic water-use determinants. Those trends are largely encouraging. Over the past 35 years, withdrawals in industry and at thermoelectric plants have steadily dropped per unit of output, and over the past 15 years some irrigated regions have also increased the efficiency of their water use. Further, per-capita domestic withdrawals may have finally peaked. If these trends continue, aggregate withdrawals in the U.S. over the next 40 years will stay below 10% of the 1995 level, despite a 41% expected...

This report documents trends in wildlife resources for the nation as required by the Renewable Resources Planning Act (RPA) of 1974. The report focuses on recent historical trends in wildlife as one indicator of ecosystem health across the United States and updates wildlife trends presented in previous RPA Assessments. The report also shows short- and long-term projections of some wildlife for documenting expected trajectories of resource change. National trends in four attributes of wildlife resources, including habitat, population, harvest, and users, set the context within which...

FBASE is a microcomputer relational database package that handles data collected using the R1/R4 Fish and Fish Habitat Standard Inventory Procedures (Overton and others 1997). FBASE contains standard data entry screens, data validations for quality control, data maintenance features, and summary report options. This program also prepares data for importation into an ARC/INFO Geographic Information System. Users have easy access to their habitat inventory data in both a raw and summarized format. FBASE is a stand-alone program and has minimal requirements for RAM and hard drive space,...

This assessment describes northern goshawk (Accipiter gentilis) habitat in the State of Utah. Because of fire exclusion, insect and disease epidemics, timber harvest, livestock grazing, or a combination of these factors the forests and woodlands of Utah have changed drastically since the early 1900's. Forests are now dominated by mid- and late successional species (Douglas-fir, white fir, and subalpine fir) rather than the early successional species (lodgepole and ponderosa pine). Along with these changes came suspected declines in goshawk populations. Goshawk habitat in Utah was assessed...

Once found throughout the Rocky Mountains and forests of the northern states, the lynx now hides in pockets of its former range while feeding mostly on small animals like snowshoe hares. A team of government and university scientists review the newest scientific knowledge of this unique cat's history, distribution, and ecology. The chapters on this web site provide information for current scientific and public debates regarding the fate of the lynx in the United States. Chapters look at the relationships among lynx, its habitat, and its prey. The attributes of northern versus southern lynx...

An apparatus and method for the moisture content measurement of compressible materials using pressure to firmly hold surface probes against the marerial to be measured. The apparatus uses moisture measurement circuitry employed in frequency domain impedance or time domain reflectometry devices to obtain moisture content readings from materials. These moisture content readings are based on the apparent dielectric constant of the measured material. Subsurface air voids or gaps found in loose layered materials undesirably influence moisture measurement readings by reducing the apparent...

Prescribed fire is used as a site treatment after timber harvesting. These fires result in spatial patterns with some portions consuming all of the forest floor material (duff) and others consuming little. Prior to the burn, spatial sampling of duff thickness and duff water content can be used to generate geostatistical spatial simulations of these characteristics. Results from field studies indicated that spatial patterns of duff characteristics occurred, and they were then modeled by kriging, simulation and a trend-surface modeling techniques. The higher elevations of the study unit...

The subgenus Tridentatae of Artemisia (Asteraceae: Anthemideae) is composed of 11 species of various taxonomic and geographic complexities. It is centered on Artemisia tridentata with its three widespread common subspecies and two more geographically confined ones. Meiotic chromosome counts on pollen mother cells and mitotic chromosome counts on root tips were made on 364 populations (X = 3.1 plants per population). These population counts are ~60% of all Tridentatae counts. Some are first records for taxa. The Tridentatae are a polyploid complex (x = 9) with ploidy levels from 2x to 8x,...

We collected 2,665 hr of behavioral information using video surveillance on 19 Mexican Spotted Owl (Strix occidentalis lucida) pairs between 25 April and 26 July 1996. Prey deliveries per day increased as the nesting season progressed, with an average of 2.68 prey deliveries during incubation, 4.10 items during brooding, and 4.51 items during the nestling phase. The highest delivery rates were concentrated between l-3 hours before sunrise (02:00-05:00) and l-3 hours after sunset (18:00-21:00). Trip duration during diurnal hours increased 14 fold from incubation through the nestling phase,...

This report stems from Congressional concern over the equivalency between Federal payments to counties containing Federal resource management lands, the likely tax liability, and other county-level benefits and costs associated with those lands. Results indicate that the overall tax liability on Federal lands is almost three times the Federal payments. A survey of county executive officers indicates that the direct fiscal costs or benefits to county governments from Federal lands and programs are modest.