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The predictions from most forest ecosystem models originate from deterministic simulations. However, few evaluation exercises for model outputs are performed by either model developers or users. This issue has important consequences for decision makers using these models to develop natural resource management policies, as they cannot evaluate the extent to...

Black corals (order Antipatharia) are important long-lived, habitat-forming, sessile, benthic suspension feeders that are found in all oceans and are usually found in water depths greater than 30 m. Deep-water black corals are some of the slowest-growing, longest-lived deep-sea corals known. Previous age dating of a limited number of black...

[No abstract available]...

Humanity is confronted with an enormous challenge, as succinctly stated by the late Steven Schneider (2001; quoted by Jantzen 2004*): “Humans are forcing the Earth’s environmental systems to change at a rate that is more advanced than their knowledge of the consequences.” Geobiologists and low-temperature geochemists characterize material from the...

Great interest currently exists for developing ecosystem models to forecast how ecosystem services may change under alternative land use and climate futures. Ecosystem services are diverse and include supporting services or functions (e.g., primary production, nutrient cycling), provisioning services (e.g., wildlife, groundwater), regulating services (e.g., water purification, floodwater retention), and...

The thick (≤8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high δ34S values (−11.6 to 40.8‰, >70% exceed 10‰; 51 analyses) derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes...

We conducted standardized surveys for marine birds in Glacier Bay in seven years between 1991 and 2008. From our most recent survey, a combination of line- and strip-transect methods completed in 2008, we estimated that 4981 (95% CI 1293–8670) Kittlitz’s Murrelets Brachyramphus brevirostris resided in Glacier Bay during the month...

We estimated the densities of rainbow smelt (Osmerus mordax) using hydroacoustics and obtained specimens for diet analysis and groundtruthed acoustics data from mid‐water trawl sampling in four areas of Lake Champlain, USA–Canada. Densities of rainbow smelt cohorts alternated during the 2‐year study; age‐0 rainbow smelt were very abundant in 2001...

The Eurasian freshwater tubenose goby Proterorhinus semilunaris (formerly Proterorhinus marmoratus) invaded the Laurentian Great Lakes in the 1990s, presumably via ballast water from transoceanic cargo ships. Tubenose gobies spread throughout Lake St. Clair, its tributaries, and the Detroit River system, and also are present in the Duluth-Superior harbor of Lake...

SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed to estimate nutrient inputs [total nitrogen (TN) and total phosphorus (TP)] to the northwestern part of the Gulf of Mexico from streams in the South‐Central United States (U.S.). This area included drainages of the Lower Mississippi, Arkansas‐White‐Red, and Texas‐Gulf hydrologic...

Iron (Fe) availability is a major limiting factor for primary production in aquatic environments. Cyanobacteria respond to Fe deficiency by derepressing the isiAB operon, which encodes the antenna protein IsiA and flavodoxin. At nanomolar Fe concentrations, a PSI−IsiA supercomplex forms, comprising a PSI trimer encircled by two complete IsiA rings. This PSI−IsiA...

Recruitment of burbot Lota lota in eastern Lake Erie, estimated by catches of age-4 burbot, was high during 1997–2001 and then abruptly declined to low levels during 2002–2007. The invasive round goby Neogobius melanostomus, a benthic species, was first collected in trawl assessments in eastern Lake Erie in 1999, and...

Tree-ring carbon and oxygen isotope ratios from live and recently dead trees may reveal important mechanisms of tree mortality. However, wood decay in dead trees may alter the δ13C and δ18O values of whole wood obscuring the isotopic signal associated with factors leading up to and including physiological death. We...

Two protocetid whale vertebrae, here referred to “Eocetus” wardii, have been recovered from the riverbed of the Pamunkey River in east-central Virginia. Neither bone was found in situ, but both were found with lumps of lithified matrix cemented to their surfaces. Most of this matrix was removed and processed for...

Aim To identify whether eradication or containment is expected to be the most cost‐effective management goal for an isolated invasive population when knowledge about the current extent is uncertain.Location Global and South Africa.Methods We developed a decision analysis framework to analyse the best management goal for an invasive species population (eradication, containment or...

The scale of previously proposed methods for mapping site-response ranges from global coverage down to individual urban regions. Typically, spatial coverage and accuracy are inversely related.We use the densely spaced strong-motion stations in Parkfield, California, to estimate the accuracy of different site-response mapping methods and demonstrate a method for integrating...

Depth reduction is a natural process in floodplain lakes, but in many basins has been accelerated by anthropogenic disturbances. A diverse set of 42 floodplain lakes in the Yazoo River Basin (Mississippi, USA) was examined to test the hypothesis of whether depth reduction was a key determinant of water quality...

Debris flows typically occur when intense rainfall or snowmelt triggers landslides or extensive erosion on steep, debris-mantled slopes. The flows can then grow dramatically in size and speed as they entrain material from their beds and banks, but the mechanism of this growth is unclear. Indeed, momentum conservation implies that...

No abstract available....

Two high-head dams on the Elwha River in Washington State (USA) have changed the migratory patterns of resident and anadromous fish, limiting Pacific salmon to the lower 7.9 km of a river that historically supported large Pacific salmon runs. To document the effects of the dams prior to their removal, we...

Animal species across multiple taxa demonstrate multi-annual population cycles, which have long been of interest to ecologists. Correlated population cycles between species that do not share a predator–prey relationship are particularly intriguing and challenging to explain. We investigated annual population trends of greater sage-grouse (Centrocercus urophasianus) and cottontail rabbits (Sylvilagus sp.)...

[No abstract available]...

 Full‐resolution 3D Ground‐Penetrating Radar (GPR) data were combined with high‐resolution hydraulic conductivity (K) data from vertical Direct‐Push (DP) profiles to characterize a portion of the highly heterogeneous MAcro Dispersion Experiment (MADE) site. This is an important first step to better understand the influence of aquifer heterogeneities on observed anomalous...

Groundwater contamination by tetrachloroethene and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry‐cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former above‐ground storage tanks. Free‐phase tetrachloroethene from...

This paper examines the relationship between offshore wave climate and nearshore waves and currents at Hanalei Bay, Hawaii, an exposed bay fringed with coral reefs. Analysis of both offshore in situ data and numerical hindcasts identify the predominance of two wave conditions: a mode associated with local trade winds and...