Publications

Cores and borehole-geophysical logs collected on and around two tree islands in Water Conservation Area 3 have been examined to develop a stratigraphic framework for these ecosystems. Especially important is the potential for the exchange of ground water and surface water within these features. The hydrostratigraphic results from this study document the lithologic nature of the...

No abstract available.

The tree species Xylocarpus granatum is commonly described as occurring in the upper intertidal zone of mangrove forests, but mature trees are occasionally found at lower elevations. In the Utwe River basin, on the Pacific island of Kosrae, we investigated the relative importance of several biotic and abiotic factors that may control the intertidal distribution of X. granatum. Factors we...

No abstract available.

Environmental contamination has been suspected of being partially responsible for recent declines in amphibian populations. It is often not feasible to identify all of the compounds in an environment, nor the concentrations in which they are present. SPMDs are passive sampling devices that uptake lipophilic compounds from the environment in a manner similar to aquatic organisms. The...

The effects of bighead carp Hypophthalmichthys nobilis on native planktivores in the USA is unknown. The objectives of this study were to experimentally test for competitive interactions between age-0 bighead carp and age-0 paddlefish Polyodon spathula. Differences among water chemistry variables, invertebrate densities, and relative growth of fish were assessed in mesocosms. Water...

Introduction The U.S. Geological Survey (USGS) conducts scientific investigations in south Florida to improve society’s understanding of the environment and assist in the sustainable use, protection, and restoration of the Everglades and other ecosystems within the region. The investigations summarized in this document have been carried out under the Greater Everglades Science Program...

Abstract not supplied at this time

The Topeka shiner (Notropis topeka) is a small native cyprinid species that has declined throughout its range in the Central Great Plains Region of the United States. Declines of the species have been associated with numerous factors including water quality, physical habitat alteration and predation. The N. topeka occurs in the Moniteau Creek Watershed of Cooper and Moniteau Counties of...

We evaluated the roles of geomorphic and hydrologic dynamics in determining physical stream habitat in Bear Creek, a stream with a 239 km2 drainage basin in the Ozark Plateaus (Ozarks) in northern Arkansas. During a relatively wet 12-month monitoring period, the geomorphology of Bear Creek was altered by a series of floods, including at least four floods with peak discharges exceeding a...

During July 2000–September 2002, the U.S. Geological Survey collected and analyzed site-specific hydrologic, water-quality, and biological data in Dickinson Bayou, Armand Bayou, and the San Bernard River in the Gulf Coastal Plain of Texas. Segments of the three water bodies are on the State 303(d) list. Continuous monitoring showed that seasonal variations in water temperature, specific

The Texas part of the Red River Basin has been divided into five reaches or subbasins (fig. 1) to facilitate improved planning, monitoring, geographical analysis, and dissemination of information. The U.S. Geological Survey (USGS), in cooperation with the Red River Authority of Texas, is studying the five subbasins, each for a period of about 1 year. Baldys and Phillips (1998) discuss...