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Several schemes have been developed to help select the locations of marine reserves. All of them combine social, economic, and biological criteria, and few offer any guidance as to how to prioritize among the criteria identified. This can imply that the relative weights given to different criteria are unimportant. Where...

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A 9.9-ha constructed wetland designed to reduce nitrogen in municipal wastewater following conventional secondary treatment began operating in southern California's San Jacinto Valley in September 1994. The wetland incorporated zones of bulrush (Schoenoplectus acutus and S. californicus) for effluent treatment, plus areas of 1.8-m deep open water and other features...

The ability to predict when sea lampreys (Petromyzon marinus) will metamorphose from the larval phase to the parasitic phase is essential to the operation of the sea lamprey control program. During the spring of 1994, two populations of sea lamprey larvae from two rivers were captured, measured, weighed, implanted with...

The historical variability in fire regime is a conservative indicator of ecosystem sustainability. Understanding the natural role of fire in chaparral ecosystems is therefore necessary for effective fire management....

The Bufflehead Bucephala albeola predominantly in Canada and Alaska (USA). Evidence suggests that the species may have recently expanded its breeding range southward into central and south-central North Dakota. This paper presents data on observations of Buffleheads during the breeding season in Kidder County, North Dakota, 1994-2002, and discusses the...

Aim To determine the best-fit model of species–area relationships for Mediterranean-type plant communities and evaluate how community structure affects these species–area models.Location Data were collected from California shrublands and woodlands and compared with literature reports for other Mediterranean-climate regions.Methods The number of species was recorded from 1, 100 and 1000 m2...

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The efficacy of 2’, 5-dichloro-4’-nitrosalicylanilide (niclosamide) at various concentrations and exposure times was tested against free-swimming larval sea lampreys (Petromyzon marinus) at 12°C and 17°C in Lake Huron water. Concentrations of niclosamide in test solutions ranged from 0.46 to 4.7 mg/L with pH 7.8 to 8.3, total alkalinity 78 to...

A basic paradigm in behavioral ecology is that organisms expand their distribution as preferred sites become saturated with individuals that reduce the availability of resources (e.g., shelter, prey) on a per capita basis. Previous fish community studies at Stellwagen Bank National Marine Sanctuary have shown that juvenile Acadian redfish Sebastes...

The Barkol Tagh and Karlik Tagh ranges of the easternmost Tien Shan are a natural laboratory for studying the fault architecture of an active termination zone of a major intracontinental mountain range. Barkol and Karlik Tagh and lesser ranges to the north are bounded by active thrust faults that locally...

Micro-tsunami waves with a maximum amplitude of 4-6 mm were detected with the ocean-bottom pressure gauges on a cabled deep seafloor observatory south of Hokkaido, Japan, following the January 28, 2000 earthquake (Mw 6.8) in the southern Kuril subduction zone. We model the observed micro-tsunami and estimate the focal depth...

We describe a model for regional initiation of shallow landslides based on an approximate analytic solution to Richards equation combined with an infinite-slope calculation. The model applied over digital topography computes pressure heads and factors of safety as functions of depth for geographic information system (GIS) grid cells at any...

Concentrations of current-use pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine (OC) insecticides were determined above the reach of tide in the Chesterville Branch and Nanticoke River on the eastern shore of Chesapeake Bay during base-flow and storm-flow hydrologic regimes to evaluate mass transport to Chesapeake Bay. The...

Perchlorate (ClO4-) is a water-soluble, inorganic anion that is often combined with ammonium, potassium or other cations for use in industry and agriculture. Ammonium perchlorate, for example, is a potent oxidizer and is used in various military applications including rocket fuel. It has also been found in an historically widely...

Temporally and spatially varying pore-fluid pressures exert strong controls on debris-flow motion by mediating internal and basal friction at grain contacts. We analyze these effects by deriving a one-dimensional model of pore-pressure diffusion explicitly coupled to changes in debris-flow thickness. The new pore-pressure equation is combined with Iverson's (1997) extension...

Hydrologic processes control much of the export of organic matter and nutrients from the land surface. It is the variability of these hydrologic processes that produces variable patterns of nutrient transport in both space and time. In this paper, we explore how hydrologic “connectivity” potentially affects nutrient transport. Hydrologic connectivity...

Drastic reductions in diversity and abundance of mussel populations are documented in many systems. Bear Creek, located in northwest Alabama and northeast Mississippi, has seen changes to its fauna, possibly the result of impoundment, channelization, wastewater discharge, and sedimentation from such sources such as strip mining, agriculture, and silviculture. The...

This study investigates the behavior of migrant eels as they approached the Patea hydroelectric dam on the West Coast of the North Island, New Zealand. Seventeen mature migrant eels (870-1,240 mm; 2,000-6,380 g) were implanted with coded acoustic transmitters and released. Their movements in the reservoir were monitored for 14...

Stable water isotope (δ18O, δD) data from a high elevation (5100 masl) ice core recovered from the Tien Shan Mountains, Kyrgyzstan, display a seasonal cycle in deuterium excess (d = δD - 8*δ18O) related to changes in the regional hydrologic cycle during 1994-2000. While there is a strong correlation (r2 = 0.98) between δ18O and δD in the ice core samples, the regression slope (6.9) and mean d value (23.0) are significantly different than the...

New sensitive high-resolution ion microprobe-reverse geometry U-Pb detrital zircon data establish the timing of onset of foreland basin subsidence in the Magallanes basin and the age of the Patagonian Andes in southernmost Chile. Initiation of the Magallanes foreland basin is signaled by the abrupt occurrence of sandstone of the Punta...