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Factors Affecting Stream Nutrient Loads: A Synthesis of Regional SPARROW Model Results for the Continental United States1

Stephen D. Preston, Richard B. Alexander, Gregory E. Schwarz, Charles G. Crawford
2011 Journal of the American Water Resources Association  
We compared the results of 12 recently calibrated regional SPARROW (SPAtially Referenced Regressions On Watershed attributes) models covering most of the continental United States to evaluate the consistency  ...  Overall, we found that the SPARROW model results provide a consistent set of information for identifying the major sources and environmental factors affecting nutrient fate and transport in United States  ...  The United States Geological Survey's (USGS) SPAtially Referenced Regressions On Watershed attributes (SPARROW) model was developed to aid in the interpretation of monitoring data and simulate water-quality  ... 
doi:10.1111/j.1752-1688.2011.00577.x pmid:22457574 pmcid:PMC3307615 fatcat:423fec2f5vclpjjkcxl5aut2zm

Integration of Bayesian Inference Techniques with Mathematical Modeling [chapter]

G. Arhonditsis, S. Stremilov, A. Gudimov, M. Ramin, W. Zhang
2011 Treatise on Estuarine and Coastal Science  
The two eutrophication models are used in conjunction 21 with the SPAtially Referenced Regressions On Watershed attributes (SPARROW) 22 watershed model.  ...  Predictions from the two models 19 are combined using the respective standard error estimates as weights in a 20 weighted model average.  ...  The calibration exercise offered 170 estimates of the export coefficients and the delivery rates from the different 171 subcatchments and thus generated testable hypotheses regarding the nutrient 172 export  ... 
doi:10.1016/b978-0-12-374711-2.00910-4 fatcat:ztvgc5ejsff3ned6sgedmqfrai

Nutrient Inputs to the Laurentian Great Lakes by Source and Watershed Estimated Using SPARROW Watershed Models1

Dale M. Robertson, David A. Saad
2011 Journal of the American Water Resources Association  
To help address these issues, SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed for estimating loads and sources of phosphorus (P) and nitrogen (N) from the United  ...  Watersheds around Lake Erie contributed nutrients at the highest rate (similar to intensively farmed areas in the Midwest) because they have the largest nutrient inputs and highest delivery ratio.  ...  A description of the SPAtially Referenced Regression On Watershed attributes (SPARROW) model. Material S2.  ... 
doi:10.1111/j.1752-1688.2011.00574.x pmid:22457580 pmcid:PMC3307632 fatcat:7js4ouf6bjgvtn4b7vn3suvcge

A Multilevel Model of the Impact of Farm-Level Best Management Practices on Phosphorus Runoff

K.H. Reckhow, S.S. Qian, R.D. Harmel
2009 Journal of the American Water Resources Association  
In summary, the resultant multilevel model can be used to estimate phosphorus loss from farms and hence serve as a useful tool for BMP selection.  ...  For example, it was found that the effect of fertilizer application rate on farmscale phosphorus loss is a function of the application method, the hydrologic soil group, and the land use (crop type).  ...  ACKNOWLEDGMENTS We thank Melissa Kenney, Conrad Lamon, and Craig Stow for helpful reviews.  ... 
doi:10.1111/j.1752-1688.2008.00298.x fatcat:kr4xqrqkvrayrcu3idweeqwdcu

Anthropogenic Phosphorus Inputs to a River Basin and Their Impacts on Phosphorus Fluxes Along Its Upstream-Downstream Continuum

Wangshou Zhang, Dennis P. Swaney, Bongghi Hong, Robert W. Howarth
2017 Journal of Geophysical Research - Biogeosciences  
Key Points: • We describe the spatial variation of phosphorus (P) budgets in a series of nested watersheds • We propose an empirical model for predicting riverine P export in similarly nested catchments  ...  Here we investigated P budgets in a series of nested watersheds draining into Hongze Lake of China and developed an empirical function to describe the relationship between anthropogenic inputs and riverine  ...  model=hrcswj) for providing water quality and hydrological data. We would like to thank the reviewers for their valuable comments.  ... 
doi:10.1002/2017jg004004 fatcat:t24hg7zevra4pejp3fauo3fkqe

Concentrations, Loads, and Associated Trends of Nutrients Entering the Sacramento–San Joaquin Delta, California

Dina Saleh, US Geological Survey, Joseph Domagalski, US Geological Survey
2021 San Francisco Estuary and Watershed Science  
Source modeling of nitrogen and phosphorus identifies agriculture, atmospheric deposition, and wastewater effluent as sources of total nitrogen in the Central Valley.  ...  This increase suggests a possible nitrogen limitation in the northern Delta and a phosphorus limitation in the southern Delta, as indicated by the molar ratios of bioavailable nitrogen to bioavailable  ...  We thank Eric Morway for providing R code used for data interpolation, Daniel Wise for his help with the SPARROW 2012 model, as well as Tamara Kraus and Hank Johnson (USGS reviewers), and Timothy Mussen  ... 
doi:10.15447/sfews.2021v19iss4art6 fatcat:cbav6j6offaqbbdhf6ofafyxlu

A multi-modeling approach to evaluating climate and land use change impacts in a Great Lakes River Basin [chapter]

M. J. Wiley, D. W. Hyndman, B. C. Pijanowski, A. D. Kendall, C. Riseng, E. S. Rutherford, S. T. Cheng, M. L. Carlson, J. A. Tyler, R. J. Stevenson, P. J. Steen, P. L. Richards (+3 others)
2010 Global Change and River Ecosystems—Implications for Structure, Function and Ecosystem Services  
We describe a recently developed "multi-modeling" system for ecological forecasting in a 7600 km 2 watershed in the North American Great Lakes Basin.  ...  We discuss the implications of this result for regional preparations for climate change adaptation, and the extent to which the result may be constrained by our modeling methodology.  ...  Our sincere thanks to all of the many folks who contributed work in the field, on the computer, and in meetings;  ... 
doi:10.1007/978-94-007-0608-8_17 fatcat:4ixaz5emuvfotnivs3savcu3ty

A multi-modeling approach to evaluating climate and land use change impacts in a Great Lakes River Basin

M. J. Wiley, D. W. Hyndman, B. C. Pijanowski, A. D. Kendall, C. Riseng, E. S. Rutherford, S. T. Cheng, M. L. Carlson, J. A. Tyler, R. J. Stevenson, P. J. Steen, P. L. Richards (+3 others)
2010 Hydrobiologia  
We describe a recently developed "multi-modeling" system for ecological forecasting in a 7600 km 2 watershed in the North American Great Lakes Basin.  ...  We discuss the implications of this result for regional preparations for climate change adaptation, and the extent to which the result may be constrained by our modeling methodology.  ...  Our sincere thanks to all of the many folks who contributed work in the field, on the computer, and in meetings;  ... 
doi:10.1007/s10750-010-0239-2 fatcat:r3gs6hhc7vdpln2sarih3vrs5y

Modeling dissolved oxygen dynamics and coastal hypoxia: a review

M. A. Peña, S. Katsev, T. Oguz, D. Gilbert
2009 Biogeosciences Discussions  
Modeling dissolved oxygen and hypoxia M. A. Pe ña et al.  ...  We thank SCOR for supporting the Working Group 128 on "Natural and Human-Induced Hypoxia and Consequences for Coastal Areas" and all members of this SCOR group for their contribution.  ...  Beauchemin for a careful literature survey and to W. Crawford, K. Denman, and J. Zhang whose comments helped to improve this paper.  ... 
doi:10.5194/bgd-6-9195-2009 fatcat:smjkziclvbhufbdblc5y2rnmqe

Modeling dissolved oxygen dynamics and hypoxia

M. A. Peña, S. Katsev, T. Oguz, D. Gilbert
2010 Biogeosciences  
Because hypoxia occurs in a variety of environments and can be persistent, periodic or episodic, models differ significantly in their complexity and temporal and spatial resolution.  ...  Here we review oxygen dynamics models that have significantly contributed to a better understanding of the effects of natural processes and human perturbations on the development of hypoxia, factors controlling  ...  We thank SCOR for supporting the Working Group 128 on "Natural and Human-Induced Hypoxia and Consequences for Coastal Areas" and all members of this SCOR working group for their contribution.  ... 
doi:10.5194/bg-7-933-2010 fatcat:5am57d5iaveg5jf5f2mlhe3rnq

Mapping invasive Phragmites australis in the coastal Great Lakes with ALOS PALSAR satellite imagery for decision support

Laura L. Bourgeau-Chavez, Kurt P. Kowalski, Martha L. Carlson Mazur, Kirk A. Scarbrough, Richard B. Powell, Colin N. Brooks, Brian Huberty, Liza K. Jenkins, Elizabeth C. Banda, David M. Galbraith, Zachary M. Laubach, Kevin Riordan
2013 Journal of Great Lakes research  
The goal of the present study is to focus on the short-term variability in DO depletion and its link to the rate of vertical mixing.  ...  These data emphasize the necessity of considering non-steady state accumulation dynamics for future bioenergetics and kinetics modeling of mercury. ON, L7R 4A6.  ...  HydroSPARROW, a forecasting tool that enables SPARROW (SPAtially Referenced Regression On Watershed attributes) to simulate the effects of various land-use and climate scenarios, was developed to describe  ... 
doi:10.1016/j.jglr.2012.11.001 fatcat:nkzrhb6i4fdp7eje2qd5qsahwu

INTEGRATED ASSESSMENT OF CLIMATE CHANGE AND HUMAN ACTIVITIES IMPACTS ON WATER RESOURCES AND QUALITY

Wei Li Duan
and aquatic losses/storage), and outputs (riverine nutrient export), the SPARROW modeling approach performs a nonlinear least-squares multiple regression to describe the relation between spatially referenced  ...  (5) To develop a spatially explicit, regional empirical model of suspended sediment for the Ishikari River basin in Hokkaido, on the basis of the Spatially Referenced Regression on Watershed Attributes  ... 
doi:10.14989/doctor.k18565 fatcat:dsfr7xmubvetnbunjnruppdp5m

Bulletin de veille du réseau d'écotoxicologie terrestre et aquatique N°48

Colette Bertrand, Christian Mougin, Annette Bérard, Céline Pelosi, Soizic Morin, Olivier Crouzet, Pascale Karmasyn-Veyrines
2020
The derived multiple linear regression models for estimating dissipation half-lives (DT50,S) for citalopram, clindamycin, fexofenadine, irbesartan and sulfamethoxazole always included at least one microbial  ...  We model the transport properties by two approaches: (1) we use a numerical model to simulate the structure of allophane aggregates. The algorithm is based on a cluster-cluster aggregation model.  ...  We present here a Bayesian belief network that was developed in a cooperative process between researchers specializing in Bayesian modelling, soil sciences, agronomy, and diffuse pollutants to provide  ... 
doi:10.15454/zx91-bw13 fatcat:i4d4hhsu5fh4vpljsifrfetlke