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Hydrology and climate of four watersheds in eastern Puerto Rico: Chapter C in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Sheila F. Murphy, Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-C
Puerto Rico lies directly in the path of the easterly trade winds, which deliver steady rainfall to the mountains and steer tropical wave systems toward the island. Hurricanes and tropical storms derived from these tropical waves differ in frequency and intensity, contributing to substantial interannual variation in precipitation and stream...
Atmospheric inputs to watersheds of the Luquillo Mountains in eastern Puerto Rico: Chapter D in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-D
Twenty years of precipitation-chemistry data from the National Atmospheric Deposition Program site at El Verde, Puerto Rico, demonstrate that three major sources control the composition of solutes in rain in eastern Puerto Rico. In order of importance, these sources are marine salts, temperate contamination from the Northern Hemisphere, and Sahara...
Difference infiltrometer: a method to measure temporally variable infiltration rates during rainstorms
John A. Moody, Brian A. Ebel
2012, Hydrological Processes (26) 3312-3318
We developed a difference infiltrometer to measure time series of non-steady infiltration rates during rainstorms at the point scale. The infiltrometer uses two, tipping bucket rain gages. One gage measures rainfall onto, and the other measures runoff from, a small circular plot about 0.5-m in diameter. The small size allows...
Morphological and chemical evidence of stromatolitic deposits in the 2.75 Ga Carajás banded iron formation, Brazil
Beatriz Ribeiro da Luz, James K. Crowley
2012, Earth and Planetary Science Letters (355-356) 60-72
We describe evidence of biogenicity in the morphology and carbon content of well-preserved, Neoarchean samples of banded iron formation (BIF) from Carajás, Brazil. Silica-rich BIF layers contain translucent ellipsoidal or trapezoidal structures (∼5–10 μm diameter) composed of silica, hematite, and kerogen, which are arranged in larger ring-like forms (rosettes). Stable...
Weathering processes in the Rio Icacos and Rio Mameyes watersheds in Eastern Puerto Rico: Chapter I in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Heather L. Buss, Arthur F. White
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-I
Streams draining watersheds of the two dominant lithologies (quartz diorite and volcaniclastic rock) in the Luquillo Experimental Forest of eastern Puerto Rico have very high fluxes of bedrock weathering products. The Río Blanco quartz diorite in the Icacos watershed and the Fajardo volcaniclastic rocks in the Mameyes watershed have some...
Physiography, geology, and land cover of four watersheds in eastern Puerto Rico: Chapter A in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Sheila F. Murphy, Robert F. Stallard, Matthew C. Larsen, William A. Gould
Sheila F. Murphy, editor(s)
2012, Professional Paper 1789-A
Four watersheds with differing geology and land cover in eastern Puerto Rico have been studied on a long-term basis by the U.S. Geological Survey to evaluate water, energy, and biogeochemical budgets. These watersheds are typical of tropical, island-arc settings found in many parts of the world. Two watersheds are located...
Weathering, landscape equilibrium, and carbon in four watersheds in eastern Puerto Rico: Chapter H in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-H
The U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets (WEBB) program research in eastern Puerto Rico involves a double pair-wise comparison of four montane river basins, two on granitic bedrock and two on fine-grained volcaniclastic bedrock; for each rock type, one is forested and the other is developed. A confounding...
Simulating potential structural and operational changes for Detroit Dam on the North Santiam River, Oregon, for downstream temperature management
Norman L. Buccola, Stewart A. Rounds, Annett B. Sullivan, John C. Risley
2012, Scientific Investigations Report 2012-5231
Detroit Dam was constructed in 1953 on the North Santiam River in western Oregon and resulted in the formation of Detroit Lake. With a full-pool storage volume of 455,100 acre-feet and a dam height of 463 feet, Detroit Lake is one of the largest and most important reservoirs in the...
Modeling the mesozoic-cenozoic structural evolution of east texas
Ofori N. Pearson, Elisabeth L. Rowan, John J. Miller
2012, Gulf Coast Assoc of Geological Societies Journal (1) 118-128
The U.S. Geological Survey (USGS) recently assessed the undiscovered technically recoverable oil and gas resources within Jurassic and Cretaceous strata of the onshore coastal plain and State waters of the U.S. Gulf Coast. Regional 2D seismic lines for key parts of the Gulf Coast basin were interpreted in order to...
Demonstration optimization analyses of pumping from selected Arapahoe aquifer municipal wells in the west-central Denver Basin, Colorado, 2010–2109
Edward R. Banta, Suzanne S. Paschke
2012, Scientific Investigations Report 2012-5140
Declining water levels caused by withdrawals of water from wells in the west-central part of the Denver Basin bedrock-aquifer system have raised concerns with respect to the ability of the aquifer system to sustain production. The Arapahoe aquifer in particular is heavily used in this area. Two optimization analyses were...
Flood of August 11–16, 2010, in the South Skunk River Basin, central and southeast Iowa
Kimberlee K. Barnes, David A. Eash
2012, Open-File Report 2012-1202
Severe thunderstorm activity during August 8–11, 2010 in central and southeast Iowa resulted in major flooding from August 11–16, 2010, in the South Skunk River Basin. Rain gages at Ames and Story City recorded 96-hour rainfall amounts of 9.61 and 8.70 inches, respectively. The majority of the rainfall occurred during...
Effects of earthworms on slopewash, surface runoff, and fine-litter transport on a humid-tropical forested hillslope in eastern Puerto Rico: Chapter G in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Matthew C. Larsen, Zhigang Liu Liu, Xiaoming Zou
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-G
Rainfall, slopewash (the erosion of soil particles), surface runoff, and fine-litter transport were measured in tropical wet forest on a hillslope in the Luquillo Experimental Forest, Puerto Rico, from February 1998 until April 2000. Slopewash data were collected using Gerlach troughs at eight plots, each 2 square meters in area....
Land use, population dynamics, and land-cover change in eastern Puerto Rico: Chapter B in Water quality and landscape processes of four watersheds in eastern Puerto Rico
William A. Gould, Sebastián Martinuzzi, Isabel K. Pares-Ramos, Sheila F. Murphy, Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-B
We assessed current and historic land use and land cover in the Luquillo Mountains and surrounding area in eastern Puerto Rico, including four small subwatersheds that are study watersheds of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets (WEBB) program. This region occupies an area of 1,616 square kilometers,...
Water quality and mass transport in four watersheds in eastern Puerto Rico: Chapter E in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Robert F. Stallard, Sheila F. Murphy
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-E
Water quality of four small watersheds in eastern Puerto Rico has been monitored since 1991 as part of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets program. These watersheds represent a montane, humid-tropical environment and differ in geology and land cover. Two watersheds are located on granitic rocks, and...
Occurrence and potential sources of pyrethroid insecticides in stream sediments from seven U.S. metropolitan areas
Kathryn Kuivila, Michelle Hladik, Christopher G. Ingersoll, Nile E. Kemble, Patrick W. Moran, Daniel L. Calhoun, Lisa H. Nowell, Robert J. Gilliom
2012, Environmental Science & Technology (46) 4297-4303
A nationally consistent approach was used to assess the occurrence and potential sources of pyrethroid insecticides in stream bed sediments from seven metropolitan areas across the United States. One or more pyrethroids were detected in almost half of the samples, with bifenthrin detected the most frequently (41%) and in each...
Dissolved organic matter reduces algal accumulation of methylmercury
Allison C. Luengen, Nicholas S. Fisher, Brian A. Bergamaschi
2012, Environmental Toxicology and Chemistry (31) 1712-1719
Dissolved organic matter (DOM) significantly decreased accumulation of methylmercury (MeHg) by the diatom Cyclotella meneghiniana in laboratory experiments. Live diatom cells accumulated two to four times more MeHg than dead cells, indicating that accumulation may be partially an energy-requiring process. Methylmercury enrichment in diatoms relative to ambient water was measured...
The hydrology of a drained topographical depression within an agricutlural field in north-central Iowa
Jason L. Roth, Paul D. Capel
2012, Transactions of the American Society of Agricultural and Biological Engineers (55) 1801-1814
North-central Iowa is an agriculturally intensive area comprising the southeastern portion of the Prairie Pothole Region, a landscape containing a high density of enclosed topographical depressions. Artificial drainage practices have been implemented throughout the area to facilitate agricultural production. Vertical surface drains are utilized to drain the topographical depressions that...
Predicting biological condition in southern California streams
Larry R. Brown, Jason T. May, Andrew C. Rehn, Peter R. Ode, Ian R. Waite, Jonathan G. Kennen
2012, Landscape and Urban Planning (108) 17-27
As understanding of the complex relations among environmental stressors and biological responses improves, a logical next step is predictive modeling of biological condition at unsampled sites. We developed a boosted regression tree (BRT) model of biological condition, as measured by a benthic macroinvertebrate index of biotic integrity (BIBI), for streams...
A basin-scale approach for assessing water resources in a semiarid environment: San Diego region, California and Mexico
L. E. Flint, A. L. Flint, Bernard J. Stolp, W.R. Danskin
2012, Hydrology and Earth System Sciences (16) 3817-3833
Many basins throughout the world have sparse hydrologic and geologic data, but have increasing demands for water and a commensurate need for integrated understanding of surface and groundwater resources. This paper demonstrates a methodology for using a distributed parameter water-balance model, gaged surface-water flow, and a reconnaissance-level groundwater flow model...
Watershed regressions for pesticides (warp) models for predicting atrazine concentrations in Corn Belt streams
Wesley W. Stone, Robert J. Gilliom
2012, Journal of the American Water Resources Association (48) 970-986
Watershed Regressions for Pesticides (WARP) models, previously developed for atrazine at the national scale, are improved for application to the United States (U.S.) Corn Belt region by developing region-specific models that include watershed characteristics that are influential in predicting atrazine concentration statistics within the Corn Belt. WARP models for the...
Investigation of land subsidence in the Houston-Galveston region of Texas by using the Global Positioning System and interferometric synthetic aperture radar, 1993-2000
Gerald W. Bawden, Michaela R. Johnson, Mark C. Kasmarek, Justin T. Brandt, Clifton S. Middleton
2012, Scientific Investigations Report 2012-5211
Since the early 1900s, groundwater has been the primary source of municipal, industrial, and agricultural water supplies for the Houston-Galveston region, Texas. The region's combination of hydrogeology and nearly century-long use of groundwater has resulted in one of the largest areas of subsidence in the United States; by 1979, as...
Compartment-based hydrodynamics and water quality modeling of a northern Everglades wetland, Florida, USA
Hongqing Wang, Ehab A. Meselhe, Michael G. Waldon, Matthew C. Harwell, Chunfang Chen
2012, Ecological Modelling (247) 273-285
The last remaining large remnant of softwater wetlands in the US Florida Everglades lies within the Arthur R. Marshall Loxahatchee National Wildlife Refuge. However, Refuge water quality today is impacted by pumped stormwater inflows to the eutrophic and mineral-enriched 100-km canal, which circumscribes the wetland. Optimal management is a challenge...
Hydrozincite seasonal precipitation at Naracauli (Sardinia – Italy): Hydrochemical factors and morphological features of the biomineralization process
D. Medas, R. Cidu, P. Lattanzi, F. Podda, Richard B. Wanty, G. De Giudici
2012, Applied Geochemistry (27) 1814-1820
Hydrozincite [Zn5(CO3)2(OH)6] precipitation from Naracauli waters (SW Sardinia) is, among other things, promoted by a microbial community made up of a filamentous cyanobacterium (Scytonema sp.) and a microalgae (Chlorella sp.). Hydrozincite bioprecipitation is responsible for the natural removal of harmful metals, especially Zn, from the stream waters. Thus, hydrozincite could be used...
Geologic assessment of undiscovered conventional oil and gas resources--Middle Eocene Claiborne Group, United States part of the Gulf of Mexico Basin
Paul C. Hackley
2012, Open-File Report 2012-1144
The Middle Eocene Claiborne Group was assessed using established U.S. Geological Survey (USGS) assessment methodology for undiscovered conventional hydrocarbon resources as part of the 2007 USGS assessment of Paleogene-Neogene strata of the United States part of the Gulf of Mexico Basin including onshore and State waters. The assessed area is...
Archive of digital boomer subbottom profile data collected in the Atlantic Ocean offshore northeast Florida during USGS cruises 03FGS01 and 03FGS02 in September and October of 2003
Karynna Calderon, Arnell S. Forde, Shawn V. Dadisman, Dana S. Wiese, Daniel C. Phelps
2012, Data Series 670
In September and October of 2003, the U.S. Geological Survey (USGS), in cooperation with the Florida Geological Survey, conducted geophysical surveys of the Atlantic Ocean offshore northeast Florida from St. Augustine, Florida, to the Florida-Georgia border. This report serves as an archive of unprocessed digital boomer subbottom profile data, trackline...