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The diversity of ecosystems across boreal landscapes, successional changes after disturbance and complicated permafrost histories, present enormous challenges for assessing how vegetation, water and soil carbon may respond to climate change in boreal regions. To address this complexity, we used a chronosequence approach to assess changes in vegetation composition, water...

Increased stream temperatures due to global climate change, livestock grazing, removal of riparian cover, reduction of stream flow, and urbanization will have important implications for fishes worldwide. Information exists that describes the effects of elevated water temperatures on fish eggs, but less information is available on the effects of fluctuating...

Organic contaminants and trace elements were measured in bed sediments collected from streams in seven metropolitan study areas across the United States to assess concentrations in relation to urbanization. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, organochlorine pesticides, the pyrethroid insecticide bifenthrin, and several trace elements were significantly related to urbanization across...

We evaluated the influence of sex and reproductive condition on seasonal distribution and movement patterns of Lake Sturgeon Acipenser fulvescens in Namakan Reservoir, Minnesota–Ontario. Blood samples were collected from 133 Lake Sturgeon prior to spawning and plasma concentrations of testosterone and estradiol-17ß were analyzed using radioimmunoassay. Steroid concentrations were used to determine...

No abstract available....

Glaciers of the conterminous United States have been receding for the past century. Since 1900 the recession has varied from a 24 % loss in area (Mt. Rainier, Washington) to a 66 % loss in the Lewis Range of Montana. The rates of retreat are generally similar with a rapid loss in...

The Mississippi coastline is 113 linear kilometers (70 miles) long and its estuaries cover approximately 594 km (369 mi; Figure 1) (Handley and others, 2007). It has a man-made sand beach 43.5 km (27 mi) long and 595.5 km (370 mi) of shoreline (Klein and others, b., 1998). The Mississippi...

Hormones play a critical role in maintaining body fluid balance in euryhaline fishes during changes in environmental salinity. The neuroendocrine axis senses osmotic and ionic changes, then signals and coordinates tissue-specific responses to regulate water and ion fluxes. Rapid-acting hormones, e.g. angiotensins, cope with immediate challenges by controlling drinking rate...

On 29 May 2010, at approximately 11:48 UTC, an undersea volcano south of Sarigan in the Northern Mariana Islands (Figs. 1 and 2) erupted sending a cloud of volcanic ash and water vapor to 40,000 feet (12 km; Washington Volcanic Ash Advisory Center). Bathymetric data (Stern and Smoot, 1998; Embley et al., 2007)...

Hydrological processes of the wetland complex in the Prairie Pothole Region (PPR) are difficult to model, partly due to a lack of wetland morphology data. We used Light Detection And Ranging (LiDAR) data sets to derive wetland features; we then modelled rainfall, snowfall, snowmelt, runoff, evaporation, the “fill-and-spill” mechanism, shallow...

Tidal marsh functions are driven by interactions between tides, landscape morphology, and emergent vegetation. Less often considered are the diurnal pattern of tide extremes and seasonal variation of solar insolation in the mix of tidal marsh driver interactions. This work demonstrates how high-frequency hydroperiod and water temperature variability emerges from...

Increasing human populations on the landscape and globe coincide with increasing demands for food, energy, and other natural resources, with generally negative impacts to wildlife habitat, air and water quality, and natural scenery. Here we define and describe the impacts of land-use change on ecosystem services – the services that...

The Galveston Bay estuary is located on the upper Texas Gulf coast (Lester and Gonzalez, 2002). It is composed of four major sub-bays - Galveston, Trinity, East, and West Bays. It is Texas’ largest estuary on the Gulf Coast with a total area of 155,399 hectares (384,000 acres) and 1,885...

The Black-capped Petrel Pterodroma hasitata was believed extinct throughout much of the 20th century. It is the only gadfly petrel currently known to breed in the Caribbean Basin. Now seriously endangered, the species is presumed extirpated from Martinique, Dominica, and Guadeloupe, and breeding populations currently occur only on Hispaniola and perhaps Cuba....

Marine sands highly saturated with gas hydrates are potential energy resources, likely forming from methane dissolved in pore water. Laboratory fabrication of gas hydrate-bearing sands formed from dissolved-phase methane usually requires 1–2 months to attain the high hydrate saturations characteristic of naturally occurring energy resource targets. A series of gas hydrate...

Tropical Storms Irene and Lee in 2011 produced intense precipitation and flooding in the U.S. Northeast, including the Hudson River watershed. Sediment input to the Hudson River was approximately 2.7 megaton, about 5 times the long-term annual average. Rather than the common assumption that sediment is predominantly trapped in the...

http://imwa.info/docs/imwa_2013/IMWA2013_Campbell_481.pdf...

Manning’s roughness coefficient (n) has been widely used in the estimation of flood discharges or depths of flow in natural channels. Therefore, the selection of appropriate Manning’s nvalues is of paramount importance for hydraulic engineers and hydrologists and requires considerable experience, although extensive guidelines are available. Generally,...

Timely information on the availability of water and forage is important for the sustainable development of pastoral regions. The lack of such information increases the dependence of pastoral communities on perennial sources, which often leads to competition and conflicts. The provision of timely information is a challenging task, especially due...

This work demonstrates how available knowledge can be used to build more transparent and refutable computer models of groundwater systems. The Death Valley regional groundwater flow system, which surrounds a proposed site for a high level nuclear waste repository of the United States of America, and the Nevada National Security...

The Rio Naracauli in SW Sardinia drains part of the Ingurtosu Zn–Pb mining district, and contains extreme concentrations of dissolved Zn at near-neutral pH. In the upper reaches of the stream, pH, alkalinity and Zn concentrations are such that hydrozincite [Zn5(CO3)2(OH)6] precipitates in a biologically mediated process facilitated by a...

Widespread threats to forests resulting from drought stress are prompting a re-evaluation of priorities for water management on forest lands. In contrast to the widely held view that forest management should emphasize providing water for downstream uses, we argue that maintaining forest health in the context of a changing climate...

The Yankee Fork is a large tributary of the Salmon River located in central Idaho, USA, with an extensive history of placer and dredge-mining activities. Concentrations of selenium (Se) and mercury (Hg) in various aquatic trophic levels were measured in the Yankee Fork during 2001 and 2002. Various measurements of...

We describe the modern distribution of salt-marsh and tidal-flat foraminifera from Sitkinak Island (Trinity Islands) and Simeonof Island (Shumagin Islands), Alaska, to begin development of a dataset for later use in reconstructing relative sea-level changes caused by great earthquakes along the Alaska-Aleutian subduction zone. Dead foraminifera...