3,660 research outputs found
Physiochemical, site, and bidirectional reflectance factor characteristics of uniformly moist soils
The author has identified the following significant results. The bidirectional reflectance factor (0.5 micron to 2.3 micron wavelength interval) and physiochemical properties of over 500 soils from 39 states, Brazil and Spain were measured. Site characteristics of soil temperature regime and moisture zone were used as selection criteria. Parent material and internal drainage were noted for each soil. At least five general types of soil reflectance curves were identified based primarily on the presence or absence of ferric iron absorption bands, organic matter content, and soil drainage characteristics. Reflectance in 10 bands across the spectrum was found to be negatively correlated with the natural log of organic matter content
Characteristic variations in reflectance of surface soils
Surface soil samples from a wide range of naturally occurring soils were obtained for the purpose of studying the characteristic variations in soil reflectance as these variations relate to other soil properties and soil classification. A total 485 soil samples from the U.S. and Brazil representing 30 suborders of the 10 orders of 'Soil Taxonomy' was examined. The spectral bidirectional reflectance factor was measured on uniformly moist soils over the 0.52 to 2.32 micron wavelength range with a spectroradiometer adapted for indoor use. Five distinct soil spectral reflectance curve forms were identified according to curve shape, the presence or absence of absorption bands, and the predominance of soil organic matter and iron oxide composition. These curve forms were further characterized according to generically homogeneous soil properties in a manner similar to the subdivisions at the suborder level of 'Soil Taxonomy'. Results indicate that spectroradiometric measurements of soil spectral bidirectional reflectance factor can be used to characterize soil reflectance in terms that are meaningful to soil classification, genesis, and survey
Holocene Sediment Magnetic Properties Along a Transect from Isafjardardjup to Djupall, Northwest Iceland
Holocene changes in terrestrial provenance and processes of sediment transport and deposition are tracked along a fjord-to-shelf transect adjacent to Vestfirdir, Iceland, using the magnetic properties ofmarine sediments.Magnetic susceptibility (MS) profiles of 10 cores (gravity and piston) were obtained onboard using a Bartington MS loop. Remanent magnetizations were measured at 1-cm intervals from u-channel samples taken from six cores on a cryogenic magnetometer. Between six and nine alternating field demagnetization steps were used to isolate the characteristic magnetization directions. The chronologies of the cores used in this study were determined from AMS14 C dates on mollusks and foraminifera and contrained by the regional occurrance ofthe 10,200 6 60 cal yr. BP Saksunavatn tepha. Correlative fluctuations in magneticconcentration are noted between the fjord and shelf sites, though these fluctuations are partiallymasked by regional variations in carbonate content. The onset of Neoglaciation is interpreted by changes in magnetic properties including an increase in mass magneticsusceptibility that began approximately 3000 cal yr. BP. The maximum angular deviation and the median destructive field (generally 20 mT) suggest that the natural remanent magnetization is carried by a coarse ferrimagnetite mineralogy, likely magnetite or titano-magnetite. Reproducible paleomagnetic inclination values are observed in several records, including a nearly vertical inclination around 8000 cal yr. BP, suggesting that the magnetic pole may have been proximal to Iceland, followed by an interval of much shallower inclination (6000–7000 cal yr. BP)
Effect of surface anisotropy on the hysteretic properties of a magnetic particle
We study the influence of surface anisotropy on the zero-temperature
hysteretic properties of a small single-domain magnetic particle, and give an
estimation of the anisotropy constant for which deviations from the
Stoner-Wohlfarth model are observed. We consider a spherical particle with
simple cubic crystalline structure, a uniaxial anisotropy for core spins and
radial anisotropy on the surface, and compute the hysteresis loop by solving
the local Landau-Lifshitz equations for classical spin vectors. We find that
when the surface anisotropy constant is at least of the order of the exchange
coupling, large deviations are observed with respect to the Stoner-Wohlfarth
model in the hysteresis loop and thereby the limit-of-metastability curve, due
to the non-uniform cluster-wise reversal of the magnetisation.Comment: 4 pages, 4 figures: this is a short version of cond-mat/0109411
presented at the 46th MMM Conference, Seattle November 12-16, 2001, to appear
in J. Appl. Phy
Georgian\u27s Reaction to Water Shortage: Water Conservation Behavior during the 2007 Drought
This thesis examines whether or not differences in people’s water conservation attitudes, political party orientation, severity of drought, and attention to drought news affect their engagement in water conservation behavior during a time of continued water shortage. Previously, it has been found that attitudes are predictive of intentions that relate to behaviors (e.g., Dietz et al. 2005). Democrats have been shown to be more pro-environmental then Republicans (e.g., Dunlap et al. 2000). It has also been found that severity of drought is positively related with environmental concern (e.g., Accury and Christianson 1990), and access to news information is directly related to willingness to take action (e.g., Johnson and Scicchitano 2000).
However, during a time of drought, what is the relationship between individual water conservation attitudes and behaviors? Do conventional understandings of political party orientation and water conservation behaviors hold during a time of drought? Do those living in counties that experience more severe drought engage in more water conservation behaviors? Do those who pay more attention to drought news engage in more water conservation behaviors? Using data from Georgia’s 2007 Peach State Poll, I explore the answers to these questions.
I examine how water conservation attitudes (Model 1), political party orientation (Model 2), drought severity (Model 3), attention to drought news (Model 4), sociodemographics, controls, and other factors from models 1-4 (Model 5) influenced water conservation behavior during the 2007 Georgia drought.
Results indicate that differences in people’s water conservation attitudes, political party orientation, drought severity, and attention to drought news did not significantly affect their water conservation behavior during the 2007 drought. However, race, class, and gender variables in the full model did have a significant effect, which seems to suggest that one’s location in the social stratification system affects their opportunities to engage in water conservation behavior. Therefore, environmental policy issues should not be considered apart from social issues.
The fundamental theoretical significance of the following research is that we affect and are in turn affected by the biophysical world in a dialectic fashion. Recognizing the quality, quantity, and interrelatedness of nature-society relationships is essential for future research
Leading a Judge to Water: In Search of a More Fully Formed Washington Public Trust Doctrine
Under the public trust doctrine, a state must hold certain types of natural resources, most particularly navigable waters and shorelands, in trust for the benefit of the public. For that reason, courts closely scrutinize state actions impacting these public trust resources. In Caminiti v. Boyle, the Washington State Supreme Court developed a test that addresses situations where the State transfers control of public trust resources to private parties. But no firm rule guides Washington courts where a state action impacts the public trust without an alienation. This Comment examines the review Washington courts have applied in such situations, and concludes that while certain core principles are extractable—especially the principle that Washington courts’ role under the public trust doctrine does not end with enforcing the non-alienation rule established in Caminiti—Washington public trust law in this area remains vague. This Comment argues that reference to Wisconsin’s well-developed doctrine would clarify and improve Washington’s public trust doctrine, and proposes an analytical framework inspired by that created in Wisconsin’s courts
Thompson, M. J. The Domestication of Critical Theory 2016 Rowman and Littlefield International 230 pp. £80.00 (hardback) £24.95 (paperback)
Determining density of maize canopy. 2: Airborne multispectral scanner data
Multispectral scanner data were collected in two flights over a light colored soil background cover plot at an altitude of 305 m. Energy in eleven reflective wavelength band from 0.45 to 2.6 microns was recorded. Four growth stages of maize (Zea mays L.) gave a wide range of canopy densities for each flight date. Leaf area index measurements were taken from the twelve subplots and were used as a measure of canopy density. Ratio techniques were used to relate uncalibrated scanner response to leaf area index. The ratios of scanner data values for the 0.72 to 0.92 micron wavelength band over the 0.61 to 0.70 micron wavelength band were calculated for each plot. The ratios related very well to leaf area index for a given flight date. The results indicated that spectral data from maize canopies could be of value in determining canopy density
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