A universal Model-R Coupler to facilitate the use of R functions for model calibration and analysis
Yiping Wu, Shuguang Liu, Wende Yan
2014, Environmental Modelling and Software (62) 65-69
Mathematical models are useful in various fields of science and engineering. However, it is a challenge to make a model utilize the open and growing functions (e.g., model inversion) on the R platform due to the requirement of accessing and revising the model's source code. To overcome this barrier, we...
Evapotranspiration variability and its association with vegetation dynamics in the Nile Basin, 2002–2011
Henok Alemu, Gabriel B. Senay, Armel T. Kaptue, Valeriy Kovalskyy
2014, Remote Sensing (6) 5885-5908
Evapotranspiration (ET) is a vital component in land-atmosphere interactions. In drylands, over 90% of annual rainfall evaporates. The Nile Basin in Africa is about 42% dryland in a region experiencing rapid population growth and development. The relationship of ET with climate, vegetation and land cover in the basin during 2002–2011...
Geophysical investigations of the geologic and hydrothermal framework of the Pilgrim Springs Geothermal Area, Alaska
Jonathan M.G. Glen, Darcy McPhee, Paul A. Bedrosian
2014, Conference Paper, Proceedings, Thirty-Ninth Workshop on Geothermal Reservoir Engineering
Pilgrim Hot Springs, located on the Seward Peninsula in west-central Alaska, is characterized by hot springs, surrounding thawed regions, and elevated lake temperatures. The area is of interest because of its potential for providing renewable energy for Nome and nearby rural communities. We performed ground and airborne geophysical investigations of...
Spatio-temporal patterns and climate variables controlling of biomass carbon stock of global grassland ecosystems from 1982 to 2006
Jiangzhou Xia, Shuguang Liu, Shunlin Liang, Yang Chen, Wenfang Xu, Wenping Yuan
2014, Remote Sensing (6) 1783-1802
Grassland ecosystems play an important role in subsistence agriculture and the global carbon cycle. However, the global spatio-temporal patterns and environmental controls of grassland biomass are not well quantified and understood. The goal of this study was to estimate the spatial and temporal patterns of the global grassland biomass and...
A design for a sustained assessment of climate forcings and feedbacks on land use land cover change
Thomas Loveland, Rezaul Mahmood
2014, Bulletin of the American Meteorological Society (95) 1563-1572
Land use and land cover change (LULCC) significantly influences the climate system. Hence, to prepare the nation for future climate change and variability, a sustained assessment of LULCC and its climatic impacts needs to be undertaken. To address this objective, not only do we need to determine contemporary trends in...
Land cover characterization and mapping of South America for the year 2010 using Landsat 30 m satellite data
Chandra Giri, Jordan Long
2014, Remote Sensing (6) 9494-9510
Detailed and accurate land cover and land cover change information is needed for South America because the continent is in constant flux, experiencing some of the highest rates of land cover change and forest loss in the world. The land cover data available for the entire continent are too coarse...
Estuarine removal of glacial iron and implications for iron fluxes to the ocean
Andrew W. Schroth, John Crusius, Ian Hoyer, Robert Campbell
2014, Geophysical Research Letters (41) 3951-3958
While recent work demonstrates that glacial meltwater provides a substantial and relatively labile flux of the micronutrient iron to oceans, the role of high-latitude estuary environments as a potential sink of glacial iron is unknown. Here we present the first quantitative description of iron removal in a meltwater-dominated estuary. We...
Monitoring conterminous United States (CONUS) land cover change with Web-Enabled Landsat Data (WELD)
M.C. Hansen, Alexey Egorov, P.V. Potapov, S.V. Stehman, A. Tyukavina, S.A. Turubanova, David P. Roy, S.J. Goetz, Thomas R. Loveland, J. Ju, A. Kommareddy, Valeriy Kovalskyy, C. Forsyth, T. Bents
2014, Remote Sensing of Environment (140) 466-484
Forest cover loss and bare ground gain from 2006 to 2010 for the conterminous United States (CONUS) were quantified at a 30 m spatial resolution using Web-Enabled Landsat Data available from the USGS Center for Earth Resources Observation and Science (EROS) (http://landsat.usgs.gov/WELD.php). The approach related multi-temporal WELD metrics and expert-derived...
New ichnological, paleobotanical and detrital zircon data from an unnamed rock unit in Yukon-Charley Rivers National Preserve (Cretaceous: Alaska): Stratigraphic implications for the region
Anthony R. Fiorillo, Federico Fanti, Chad Hults, Stephen T Hasiotis
2014, Palaios (29) 16-26
A paleontological reconnaissance survey on Cretaceous and Paleogene terrestrial units along the Yukon River drainage through much of east-central Alaska has provided new chronostratigraphic constraints, paleoclimatological data, and the first information on local biodiversity within an ancient, high-latitude ecosystem. The studied unnamed rock unit is most notable for its historic...
Structure and seismic hazard of the Ventura Avenue anticline and Ventura fault, California: Prospect for large, multisegment ruptures in the Western Transverse Ranges
Judith Hubbard, John H. Shaw, James F. Dolan, Thomas L. Pratt, Lee J. McAuliffe, Thomas K. Rockwell
2014, Bulletin of the Seismological Society of America (104) 1070-1087
The Ventura Avenue anticline is one of the fastest uplifting structures in southern California, rising at ∼5 mm/yr. We use well data and seismic reflection profiles to show that the anticline is underlain by the Ventura fault, which extends to seismogenic depth. Fault offset increases with depth, implying that the...
Sulfur and oxygen isotopic study of Paleozoic sediment-hosted Zn-Pb(-Ag-Au-Ba-F) deposits and associated hydrothermal alteration zones in the Nome Complex, Seward Peninsula, Alaska
W.C. Pat Shanks III, John F. Slack, Alison B. Till, Roland Thurston, Pamela Gemery-Hill
2014, GSA Special Papers (506) 235-258
Results of sulfur and oxygen isotope studies of sedimentary exhalative (SEDEX) Zn-Pb(-Ag-Au-Ba-F) deposits hosted in metamorphosed Paleozoic clastic and carbonate rocks of the Nome Complex, Seward Peninsula, Alaska, are consistent with data for similar deposits worldwide. Stable isotopic studies of the Nome Complex are challenging because the rocks have...
Normative standards for land use in Vermont: Implications for biodiversity
Charles A. Bettigole, Therese M. Donovan, Robert Manning, John Austin
2014, Biological Conservation (169) 392-400
The conversion of natural lands to developed uses poses a great threat to global terrestrial biodiversity. Natural resource managers, tasked with managing wildlife as a public trust, require techniques for predicting how much and where wildlife habitat is likely to be converted in the future. Here, we develop a methodology to estimate the “social carrying...
Predicting impacts of future human population growth and development on occupancy rates of forest-dependent birds
Michelle L. Brown, Therese Donovan, W. Scott Schwenk, David M. Theobald
2014, Biological Conservation (170) 311-320
Forest loss and fragmentation are among the largest threats to forest-dwelling wildlife species today, and projected increases in human population growth are expected to increase these threats in the next century. We combined spatially-explicit growth models with wildlife distribution models to predict the effects of human development on 5 forest-dependent...
The curved 14C vs. δ13C relationship in dissolved inorganic carbon: A useful tool for groundwater age- and geochemical interpretations
Liang-Feng Han, Niel Plummer, Pradeep Aggarwal
2014, Chemical Geology (387) 111-125
Determination of the 14C content of dissolved inorganic carbon (DIC) is useful for dating of groundwater. However, in addition to radioactive decay, the 14C content in DIC (14CDIC) can be affected by many geochemical and physical processes and numerous models have been proposed to refine radiocarbon ages of DIC in...
Correlations in distribution and concentration of calcium, copper and iron with zinc in isolated extracellular deposits associated with age-related macular degeneration
Jane M Flinn, Peter Kakalec, Ryan Tappero, Blair F. Jones, Imre Lengyel
2014, Metallomics (6) 1223-1228
Zinc (Zn) is abundantly enriched in sub-retinal pigment epithelial (RPE) deposits, the hallmarks of age-related macular degeneration (AMD), and is thought to play a role in the formation of these deposits. However, it is not known whether Zn is the only metal relevant for sub-RPE deposit formation. Because of their...
Combined global change effects on ecosystem processesin nine U.S. topographically complex areas
Melannie D. Hartman, Jill S. Baron, Holly A. Ewing, Kathleen Weathers
2014, Biogeochemistry (119) 85-108
Concurrent changes in climate, atmospheric nitrogen (N) deposition, and increasing levels of atmospheric carbon dioxide (CO2) affect ecosystems in complex ways. The DayCent-Chem model was used to investigate the combined effects of these human-caused drivers of change over the period 1980–2075 at seven forested montane and two alpine watersheds in...
Self-recognition in corals facilitates deep-sea habitat engineering
Sebastian J Hennige, Cheryl L. Morrison, Armin U. Form, Janina Buscher, Nicholas A. Kamenos, J. Murray Roberts
2014, Scientific Reports (4) 1-7
The ability of coral reefs to engineer complex three-dimensional habitats is central to their success and the rich biodiversity they support. In tropical reefs, encrusting coralline algae bind together substrates and dead coral framework to make continuous reef structures, but beyond the photic zone, the cold-water coral Lophelia pertusa also...
13.3 – Stable Isotope Geochemistry of Mineral Deposits
W.C. Pat Shanks III
2014, Book chapter, Reference module in earth systems and environmental sciences: Treatise on geochemistry (Second Edition)
In this chapter, the intent is to summarize the results of traditional stable isotope studies (mainly H, B, O, C, and S) that have greatly contributed to the understanding of ore-forming processes over the last 60 years and to provide an up-to-date assessment of the application of new nontraditional isotope...
Distributed Evaluation of Local Sensitivity Analysis (DELSA), with application to hydrologic models
O. Rakovec, Mary C. Hill, M.P. Clark, A. H. Weerts, A. J. Teuling, R. Uijlenhoet
2014, Water Resources Research (50) 409-426
This paper presents a hybrid local-global sensitivity analysis method termed the Distributed Evaluation of Local Sensitivity Analysis (DELSA), which is used here to identify important and unimportant parameters and evaluate how model parameter importance changes as parameter values change. DELSA uses derivative-based “local” methods to obtain the distribution of parameter...
Changes in vegetation and biological soil crust communities on sand dunes stabilizing after a century of grazing on San Miguel Island, Channel Island National Park, California
Kristine L. Zellman
2014, Monographs of the Western North American Naturalist (7) 225-245
San Miguel Island is the westernmost of the California Channel Islands and one of the windiest areas on the west coast of North America. The majority of the island is covered by coastal sand dunes, which were stripped of vegetation and subsequently mobilized due to droughts and sheep ranching during...
Evaluation of statistically downscaled GCM output as input for hydrological and stream temperature simulation in the Apalachicola–Chattahoochee–Flint River Basin (1961–99)
Lauren E. Hay, Jacob H. LaFontaine, Steven L. Markstrom
2014, Earth Interactions (18) 1-32
The accuracy of statistically downscaled general circulation model (GCM) simulations of daily surface climate for historical conditions (1961–99) and the implications when they are used to drive hydrologic and stream temperature models were assessed for the Apalachicola–Chattahoochee–Flint River basin (ACFB). The ACFB is a 50 000 km2 basin located in the...
USGS48 Puerto Rico precipitation - A new isotopic reference material for δ2H and δ18O measurements of water
Haiping Qi, Tyler B. Coplen, Lauren V. Tarbox, Jennifer M. Lorenz, Martha A. Scholl
2014, Isotopes in Environmental and Health Studies (50) 442-447
A new secondary isotopic reference material has been prepared from Puerto Rico precipitation, which was filtered, homogenised, loaded into glass ampoules, sealed with a torch, autoclaved to eliminate biological activity, and calibrated by dual-inlet isotope-ratio mass spectrometry. This isotopic reference material, designated as USGS48, is intended to be one of...
Effects of iron on optical properties of dissolved organic matter
Brett Poulin, Joseph N. Ryan, George R. Aiken
2014, Environmental Science & Technology (48) 10098-10106
Iron is a source of interference in the spectroscopic analysis of dissolved organic matter (DOM); however, its effects on commonly employed ultraviolet and visible (UV–vis) light adsorption and fluorescence measurements are poorly defined. Here, we describe the effects of iron(II) and iron(III) on the UV–vis absorption and fluorescence of solutions...
The temperature-productivity squeeze: Constraints on brook trout growth along an Appalachian river continuum
J. Todd Petty, David Thorne, Brock M. Huntsman, Patricia M. Mazik
2014, Hydrobiologia (727) 151-166
We tested the hypothesis that brook trout growth rates are controlled by a complex interaction of food availability, water temperature, and competitor density. We quantified trout diet, growth, and consumption in small headwater tributaries characterized as cold with low food and high trout density, larger tributaries characterized as cold with...
Equations for calculating hydrogeochemical reactions of minerals and gases such as CO2 at high pressures and temperatures
C.A.J. Appelo, David L. Parkhurst, V.E.A. Post
2014, Geochimica et Cosmochimica Acta (125) 49-67
Calculating the solubility of gases and minerals at the high pressures of carbon capture and storage in geological reservoirs requires an accurate description of the molar volumes of aqueous species and the fugacity coefficients of gases. Existing methods for calculating the molar volumes of aqueous species are limited to...
