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Understanding relative sea level (RSL) rise during periods of rapid climatic change is critical for evaluating modern sea level rise given the vulnerability of Antarctic ice shelves to collapse [Hodgson et al, 2006], the retreat of the world's glaciers [Oerlemans, 2005], and mass balance trends of the Greenland ice sheet [Rignot and...

Cladophora, a nuisance and invasive, filamentous algae (Chlorophyta), massively accumulates along the shores of the lower Great Lakes each summer causing great economic damage and compromising recreational opportunity and perhaps public health. In vitro experiments showed that Cladophora samples were physically and biologically degraded when subjected to TiO2-mediated photocatalysis. For...

We evaluated the susceptibility of Rio Grande cutthroat trout (RGCT) Oncorhynchus clarkii virginalis to infection by Myxobolus cerebralis in a laboratory experiment. In the same experiment, rainbow trout (RBT) O. mykiss were similarly exposed to M. cerebralis as a reference of known sensitivity to the parasite. Treatments consisting of six...

INTRODUCTIONThe Regional Earthquake Likelihood Models (RELM) project aims to produce and evaluate alternate models of earthquake potential (probability per unit volume, magnitude, and time) for California. Based on differing assumptions, these models are produced to test the validity of their assumptions and to explore which models should be incorporated...

Adult rare minnow (Gobiocypris rarus) were exposed to 0, 1, 5, and 25 ng/l (nominal concentrations) of 17α-ethynylestradiol (EE2) and 3, 10, and 30 μg/l (nominal concentrations) of 4-nonylphenol (NP) under flow-through conditions for a period of 28 d. Low mortality was observed at 5 and 25 ng/l EE2 and the growth of...

The impact of river outfalls on beach water quality depends on numerous interacting factors. The delivery of contaminants by multiple creeks greatly complicates understanding of the source contributions, especially when pollution might originate up- or down-coast of beaches. We studied two beaches along Lake Michigan that are located between two...

We produced the first geologic map of the Amirani-Gish Bar region of Io, the last of four regional maps generated from Galileo mission data. The Amirani-Gish Bar region has five primary types of geologic materials: plains, mountains, patera floors, flows, and diffuse deposits. The flows and patera floors are thought...

Crater Lake, Oregon, is a mid-latitude caldera lake famous for its depth (594 m) and blue color. Recent underwater spectral measurements of solar radiation (300-800 nm) support earlier observations of unusual transparency and extend these to UV-B wavelengths. New data suggest that penetration of solar UVR into Crater Lake has...

Elkhorn Slough is a small estuary in Central California, where nutrient inputs are dominated by runoff from agricultural row crops, a golf course, and residential development. We examined the variability in nutrient concentrations from decadal to hourly time scales in Elkhorn Slough to compare forcing by physical and biological factors....

The inner continental shelf off northern South Carolina is a sediment-limited environment characterized by extensive hardground areas, where coastal plain strata and ancient channel-fill deposits are exposed at the sea floor. Holocene sand is concentrated in large shoals associated with active tidal inlets, an isolated shore-detached sand body, and a...

Geomorphological mapping provides evidence for two former low-level corrie glaciers on Hoy, both defined by end moraines. Five 10Be exposure ages obtained from sandstone boulders on moraine crests fall within the range 12.4±1.5 ka to 10.4±1.7 ka (weighted mean 11.7±0.6 ka), confirming that these glaciers developed during the Loch Lomond...

Effective management of introduced species requires the early identification of species that pose a significant threat of becoming invasive. To better understand the invasive ecology of species in New England, USA, we compiled a character data set with which to compare non-native species that are known invaders to non-native species...

The colonial ascidian Didemnum sp. is present on the Georges Bank fishing grounds in a gravel habitat where the benthic invertebrate fauna has been monitored annually since 1994. The species was not noted before 2002 when large colonies were first observed; and by 2003 and 2004 it covered large areas...

Following the work exploring Korolev Crater (Armstrong et al., 2005) for evidence of crater interior ice deposits, we have conducted a survey of Thermal Emission Spectroscopy (TES) temperature and albedo measurements for Mars' northern polar craters larger than 10 km. Specifically, we identify a class of craters that exhibits brightening...

A comprehensive set of downhole measurements was collected in the AND-1B drillhole as part of the on-ice scientific programme defined for the McMurdo Ice Shelf (MIS) Project. Geophysical logs were recorded over two operation phases and consisted of calliper, temperature, fluid conductivity, induction resistivity, magnetic susceptibility, natural gamma activity, acoustic...

There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the...

Tsunamis rank among the most devastating and unpredictable natural hazards to affect coastal areas. Just 3 years ago, in December 2004, the Indian Ocean tsunami caused more than 225,000 deaths. Like many extreme events, however, destructive tsunamis strike rarely enough that written records span too little time to quantify tsunami...

Florida manatees (Trichechus manatus latirostris) are marine mammals that inhabit the coastal waters and rivers of the southeastern USA, primarily Florida. Previous studies have shown that Florida manatees have low mitochondrial DNA variability, suggesting that nuclear DNA loci are necessary for discriminatory analyses. Here we report 10 polymorphic microsatellite loci...

Flexible time budgets allow individual animals to buffer the effects of variable food availability by allocating more time to foraging when food density decreases. This trait should be especially important for marine predators that forage on patchy and ephemeral food resources. We examined flexible time allocation by a long-lived marine...

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Land evaluation factors often contain continuous-, discrete- and nominal-valued attributes. In traditional land evaluation, these different attributes are usually graded into categorical indexes by land resource experts, and the evaluation results rely heavily on experts' experiences. In order to overcome the shortcoming, we presented a fuzzy neural network ensemble method...

To classify recharge potential (RCP) in ephemeral-stream channels, a method was developed that incorporates information about channel geometry, vegetation characteristics, and bed-sediment apparent electrical conductivity (??a). Recharge potential is not independently measurable, but is instead formulated as a site-specific, qualitative parameter. We used data from 259 transects across two ephemeral-stream...

Bird populations are influenced by a variety of factors at both small and large scales that range from the presence of suitable nesting habitat, predators, and food supplies to climate conditions and land-use patterns. We evaluated the influences of regional climate and land-use variables on wetland breeding birds in the...

Created wetlands are increasingly used to mitigate wetland loss. Thus, identifying wetland creation methods that enhance ecosystem development might increase the likelihood of mitigation success. Noting that the microtopographic variation found in natural wetland settings may not commonly be found in created wetlands, this study explores relationships between induced microtopography,...

Molecular hydrogen (H2) is an important intermediate product and electron donor in microbial metabolism. Concentrations of dissolved H 2 are often diagnostic of the predominant terminal electron-accepting processes in ground water systems or aquatic sediments. H2 concentrations are routinely measured in ground water monitoring wells but are rarely measured in...