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The upper part of the Dakota Sandstone exposed on the Sevilleta National Wildlife Refuge, northern Socorro County, New Mexico, is a condensed, Upper Cretaceous, marine succession spanning the first five middle Cenomanian ammonite zones of the U.S. Western Interior. Farther north in New Mexico these five ammonite zones occur over...

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...

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...

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...

Background. Social scientists have suggested that cultural diversity in a nation leads to societal instability. However, societal instability may be affected not only by within-nation on ?? diversity, but also diversity between a nation and its neighbours or ?? diversity. It is also necessary to distinguish different domains of diversity,...

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...

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...

[No abstract available]...

Powerful molecular techniques have been developed over many decades for resolving genetic relationships, population genetic structure, patterns of gene flow, mating systems, and the amount of genetic diversity in animals. Genetic studies of turtles were among the earliest and the rapid application of new genetic tools and analytical techniques is...

Classical notions of "layer-cake stratigraphy" have been denigrated as representing an antiquated "Neptunian" view of the geologic record with the American paleontologist-stratigrapher E.O. Ulrich vilified as its quintessential advocate. Some of the extreme "layer-cake" interpretations of E.O. Ulrich are demonstrably incorrect, especially where applied in marginal marine and terrestrial settings....

The illitization process of Fe-rich smectite (nontronite NAu-2) promoted by microbial reduction of structural Fe3+ was investigated by using a thermophilic metal-reducing bacterium, Thermoanaerobacter ethanolicus, isolated from the deep subsurface. T. ethanolicus was incubated with lactate as the sole electron donor and structural Fe3+ in nontronite as the sole electron...

Similar lithologies and lithofacies are present in two Upper Devonian siliciclastic units, the Brallier and Foreknobs formations, in eastern West Virginia and western Virginia, USA. Specimens of an unusual trace fossil, Pteridichnites biseriatus, occur in variable numbers throughout both stratigraphic units. P. biseriatus is present in abundance in the lowermost...

Forest fires leave behind a changed ecosystem with a patchwork of surface cover that includes ash, charred organic matter, soils and soil minerals, and dead, damaged, and living vegetation. The distributions of these materials affect post-fire processes of erosion, nutrient cycling, and vegetation regrowth. We analyzed high spatial resolution (2.4??m...

The Iron Hill (Powderhorn) carbonatite complex is a 31-kM2 (12-sq mile) alkalic intrusion located about 35 km (22 miles) south-southwest of Gunnison, CO. The intrusion has been well studied and described because of its classic petrology and architecture ofa carbonatite-alkalic complex. The complex is also noteworthy because it contains enrichments...

1. We examined indirect, community-level interactions in a stream that contained non-native brown trout (Salmo trutta Linnaeus), native brook trout (Salvelinus fontinalis Mitchill) and native slimy sculpin (Cottus cognatus Richardson). Our objectives were to examine benthic invertebrate composition and prey selection of fishes (measured by total invertebrate dry mass, dry...

Although the ecological success of introduced species hinges on biotic interactions and physical conditions, few experimental studies - especially on animals - have simultaneously investigated the relative importance of both types of factors. The lack of such research may stem from the common assumption that native and introduced species exhibit...

Results from different tsunami forecasting and hazard assessment models are compared with observed tsunami wave heights from the 26 December 2004 Indian Ocean tsunami. Forecast models are based on initial earthquake information and are used to estimate tsunami wave heights during propagation. An empirical forecast relationship based only on seismic...

The multidisciplinary approach of the US Geological Survey (USGS), a principal science agency of the US Department of the Interior (DOI), to address the complex and cumulative impacts of human activities and natural events on the US coastal ecosystems has been considered remarkable for understanding and forecasting the changes. The...

The effects of solar variability on regional climate time series were examined using a sequence of physical connections between total solar irradiance (TSI) modulated by galactic cosmic rays (GCRs), and ocean and atmospheric patterns that affect precipitation and streamflow. The solar energy reaching the Earth's surface and its oceans is...

We provide the first description of the nest, eggs, and breeding behavior of the Mérida Tapaculo (Scytalopus meridanus). Data are from one pair in the moist cloud forest of Yacambu National Park, Venezuela during April–May 2004. Two nests, constructed by the same pair, were globular in structure and consisted of...

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...

Some populations of western burrowing owls (Athene cunicularia hypugaea) have declined in recent decades. To design and implement effective recovery efforts, we need a better understanding of how distribution and demographic traits are influenced by habitat quality. To this end, we measured spatial patterns of burrowing owl breeding habitat selection...

To assess the environmental perturbation induced by the impact event that marks the Cretaceous-Tertiary (K-T) boundary, concentrations and isotopic compositions of bulk organic carbon were determined in sedimentary rocks that span the terrestrial K-T boundary at Dogie Creek, Montana, and Brownie Butte, Wyoming in the Western Interior of the United...

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...

Between species and across season variation in growth was examined by tagging and recapturing individual brook trout Salvelinus fontinalis and brown trout Salmo trutta across seasons in a small stream (West Brook, Massachusetts, U.S.A.). Detailed information on body size and growth are presented to (1) test whether the two species...