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In the past, efforts to prevent catastrophic losses from natural hazards have largely been undertaken by individual property owners based on site—specific evaluations of risks to particular buildings. Public efforts to assess community vulnerability and encourage mitigation have focused on either aggregating site—specific estimates or adopting standards based upon broad...

Temporal wet-season trends from 1987 to 1998 of total N and total P concentrations (TN and TP, respectively) in 14 tributaries to the Swan-Canning Estuary in Western Australia were evaluated using the Mann-Kendall or Seasonal kendall tests. Six of the catchments drained clay soils primarily on the Darling Plateau, which...

The pattern of b-value of the frequency-magnitude relation, or mean magnitude, varies little in the Kaoiki-Hilea area of Hawaii, and the b-values are normal, with b = 0.8 in the top 10 km and somewhat lower values below that depth. We interpret the Kaoiki-Hilea area as relatively stable, normal Hawaiian...

High-resolution seismic reflection surveys document tectonic faults that displace Pleistocene and older strata just beyond the northeast termination of the New Madrid seismic zone, at the northernmost extent of the Mississippi embayment. These faults, which are part of the Fluorspar Area fault complex in southeastern Illinois, are directly in line...

We conducted weekly aerial surveys of islands along the central Maine coast from April-June of 1993-1997 and used aerial photographs to determine peak nest count dates for Double-crested Cormorants (Phalacrocorax auritus), Herring Gulls (Larus argentatus) and Great Black-Backed Gulls (Larus marinus). These data also were used to determine the potential...

Hydrothermally altered rocks can weaken volcanoes, increasing the potential for catastrophic sector collapses that can lead to destructive debris flows1. Evaluating the hazards associated with such alteration is difficult because alteration has been mapped on few active volcanoes1-4 and the distribution and severity of subsurface alteration is largely unknown on...

From 1994 through 1998, the eruption of Kîlauea, in Hawai’i, was dominated by steady-state effusion at Pu‘u ‘Ô‘ô that was briefly disrupted by an eruption 4 km uprift at Nāpau Crater on January 30, 1997. In this paper, I describe the systematic relations of whole-rock, glass, olivine, and olivine-inclusion compositions...

Tracer experiments provide information about aquifer material properties vital for accurate site characterization. Unfortunately, density‐induced sinking can distort tracer movement, leading to an inaccurate assessment of material properties. Yet existing criteria for selecting appropriate tracer concentrations are based on analysis of homogeneous media instead of media with heterogeneities typical of...

Two ensemble methods, bagging and boosting, were investigated for improving algorithm performance. Our results confirmed the theoretical explanation [1] that bagging improves unstable, but not stable, learning algorithms. While boosting enhanced accuracy of a weak learner, its behavior is subject to the characteristics of each learning algorithm....

Park managers are concerned that moose (Alces alces), caribou (Rangifer tarandus), and grizzly bears (Ursus arctos) may be avoiding areas along the 130 km road through Denali National Park as a result of high traffic volume, thus decreasing opportunities for visitors to view wildlife. A wildlife monitoring system was developed in...

The dust logger design is based on a decade of experience in the use of light sources to measure optical properties of deep Antarctic ice. Light is emitted at the top of the instrument by side-directed LEDs, scattered or absorbed by dust in the ice surrounding the borehole, and collected...

As a result of past erosion problems on the Zuni Indian Reservation in western New Mexico, the US Congress in 1990 authorized the Zuni Tribe to begin a program for watershed rehabilitation. This paper describes an approach to rank the most appropriate watersheds for rehabilitation for the Zuni Reservation. The...

Concern over the fate of plant and animal species throughout the world has accelerated over recent decades. Habitat loss is considered the main culprit in reducing many species' abundance and range, leading to numerous efforts to plan and manage habitat preservation. Our work uses Geographic Information Systems (GIS) data and...

Optical ages for five samples of tsunami-laid sand from an Oregon coastal lake were determined using an infrared optical-dating method on K-feldspar separates and, as a test of accuracy, compared to ages determined by AMS 14C dating of detrital plant fragments found in the same beds. Two optical ages were...

The Strait of Georgia is a topographic depression straddling the boundary between the Insular and Coast belts in southwestern British Columbia. Two shallow earthquakes located within the strait (M = 4.6 in 1997 and M = 5.0 in 1975) and felt throughout the Vancouver area illustrate the seismic potential of this region....

Genetic markers that differ in mode of inheritance and rate of evolution (a sex-linked Z-specific microsatellite locus, five biparentally inherited microsatellite loci, and maternally inherited mitochondrial [mtDNA] sequences) were used to evaluate the degree of spatial genetic structuring at macro- and microgeographic scales, among breeding regions and local nesting populations...

To understand the role of the world's coastal zone (CZ) in global biogeochemical fluxes (particularly those of carbon, nitrogen, phosphorus, and sediments) we must generalise from a limited number of observations associated with a few well-studied coastal systems to the global scale. Global generalisation must be based on globally available...

High-resolution aeromagnetic surveys flown over the Albuquerque basin, New Mexico, demonstrate that aeromagnetic methods can successfully map concealed and poorly exposed faults in sediment-filled basins. This is the first known use of aeromagnetic data as an aid to surficial mapping and hydrogeologic studies in a basin. Aeromagnetic maps show detailed...

Mosses and lichens are important components of boreal landscapes [Vitt et al., 1994; Bubier et al., 1997]. They affect plant productivity and belowground carbon sequestration and alter the surface runoff and energy balance. We report the use of multiresolution satellite data to map moss and lichens over the BOREAS region...

Temperature is an important variable structuring lotic biotas, but little is known about how montane landscapes function to determine stream temperatures. We developed an a priori hypothesis that was used to predict how watershed elements would interact to affect stream temperatures. The hypothesis was tested in a series of path analyses using...

Hydrologic landscapes are multiples or variations of fundamental hydrologic landscape units. A fundamental hydrologic landscape unit is defined on the basis of land-surface form, geology, and climate. The basic land-surface form of a fundamental hydrologic landscape unit is an upland separated from a lowland by an intervening steeper slope. Fundamental...

Parasites have been argued to influence clutch size evolution, but past work and theory has largely focused on within-species optimization solutions rather than clearly addressing among-species variation. The effects of parasites on clutch size variation among species can be complex, however, because different parasites can induce age-specific differences in mortality...

A stochastistic, Weibull probability model was developed and verified to simulate the underlying frequency distributions of hourly ozone (O3) concentrations (exposure dynamics) using the single, weekly mean values obtained from a passive (sodium nitrite absorbent) sampler. The simulation was based on the data derived from a co-located continuous monitor. Although...

The trout of northwest Mexico represent an undescribed group of fish considered part of the Oncorhynchus mykiss (Pacific trout) complex of species and subspecies. Recent genetic studies have shown these fish to have important genetic diversity and a unique evolutionary history when compared to coastal rainbow trout. Increased levels of...

A synthesis of available data for the Mississippi River basin (area 3 ?? 106 km2) reveals an upward trend in evaporation during recent decades, driven primarily by increases in precipitation and secondarily by human water use. A cloud-related decrease in surface net radiation appears to have accompanied the precipitation trend....