A5050971254- Soil and Water Nutrient Dynamics
- Marine and coastal ecosystems
- Hydrology and Watershed Management Studies
- Atmospheric and Environmental Gas Dynamics
- Groundwater and Isotope Geochemistry
- Aquatic Ecosystems and Phytoplankton Dynamics
- Hydrocarbon exploration and reservoir analysis
- Wastewater Treatment and Nitrogen Removal
- Fish Ecology and Management Studies
- Methane Hydrates and Related Phenomena
- Peatlands and Wetlands Ecology
- Noise Effects and Management
- Oceanographic and Atmospheric Processes
- Microbial Community Ecology and Physiology
- Water-Energy-Food Nexus Studies
- Constructed Wetlands for Wastewater Treatment
- Phosphorus and nutrient management
- Groundwater flow and contamination studies
- Air Quality and Health Impacts
- Indoor Air Quality and Microbial Exposure
- Urban Stormwater Management Solutions
- Microbial metabolism and enzyme function
- Water Quality and Pollution Assessment
- Cryospheric studies and observations
- Species Distribution and Climate Change
St. Mary's Hospital
2023
Washington State University Vancouver
2013-2022
Washington State University
2008-2020
Brunel University of London
2020
Environmental Protection Agency
2016
Chongqing Institute of Green and Intelligent Technology
2016
Liverpool John Moores University
2012
Environmental Research Institute
2010
Rutgers, The State University of New Jersey
2003-2008
University of Tennessee Health Science Center
2008
An integrated modeling approach was used to connect socioeconomic factors and nutrient management river export of nitrogen, phosphorus, silica carbon based on an updated Global NEWS model. Past trends (1970–2000) four future scenarios were analyzed. Differences among the for in agriculture a key factor affecting magnitude direction change DIN export. In contrast, connectivity level sewage treatment P detergent use more important differences DIP particulate calculated decrease all scenarios,...
Collectively, reservoirs created by dams are thought to be an important source of greenhouse gases (GHGs) the atmosphere. So far, efforts quantify, model, and manage these emissions have been limited data availability inconsistencies in methodological approach. Here, we synthesize reservoir CH4, CO2, N2O emission with three main objectives: (1) generate a global estimate GHG from reservoirs, (2) identify best predictors emissions, (3) consider effect methodology on estimates. We that water...
An overview of the first spatially explicit, multielement (N, P, and C), multiform (dissolved inorganic: DIN, DIP; dissolved organic: DOC, DON, DOP; particulate: POC, PN, PP) predictive model system river nutrient export from watersheds (Global Nutrient Export Watersheds (NEWS)) is presented. NEWS models estimate 5761 globally as a function land use, inputs, hydrology, other factors; regional global scale patterns 1995 are presented here. Watershed sources their relative magnitudes differ by...
This paper presents estimates for global N and P emissions from sewage the period 1970–2050 four Millennium Ecosystem Assessment scenarios. Using country‐specific projections population economic growth, urbanization, development of systems, wastewater treatment installations, a rapid increase in is predicted, 6.4 Tg 1.3 per year 2000 to 12.0–15.5 2.4–3.1 2050. While North America (strong increase), Oceania (moderate Europe (decrease), Asia (decrease) show contrasting developments, developing...
This paper presents a multiple linear regression model developed for describing global river export of sediments (suspended solids, TSS) to coastal seas, and approaches estimating organic carbon, nitrogen, phosphorous transported as particulate matter (POC, PN, PP) associated with sediments. The model, river‐basin spatial scale 1‐year temporal scale, is based on five factors significant influence TSS yields (the extent marginal grassland wetland rice, Fournier precipitation, slope,...
Here we describe, test, and apply a spatially explicit, global model for predicting dissolved inorganic nitrogen (DIN) export by rivers to coastal waters (NEWS‐DIN). NEWS‐DIN was developed as part of an internally consistent suite nutrient models. Modeled measured DIN values agree well (calibration R 2 = 0.79), is relatively free bias. predicts: yields ranging from 0.0004 5217 kg N km −2 yr −1 with the highest occurring in Europe South East Asia; 25 Tg , 16 anthropogenic sources; biological...
Here we describe, test, and apply a system of spatially explicit, global models for predicting river export three dissolved organic matter (DOM) components: carbon (DOC), nitrogen (DON), phosphorus (DOP). The DON DOP represent the first attempt to model in manner. DOC, DON, explain 88%, 77%, 91% variability yield (kg C, N, or P km −2 yr −1 ) from validation basins, respectively, all are relatively bias free. When applied globally, these predict that 170 Tg C , 10 N 0.6 exported by rivers...
We explored the role of aquatic systems in global N cycle using a spatially distributed, within‐basin, nitrogen (N) removal model, implemented within Framework for Aquatic Modeling Earth System (FrAMES‐N). The model predicts mean annual total (TN) by small rivers (with drainage areas from 2.6–1000 km 2 ), large rivers, lakes, and reservoirs, 30′ latitude × longitude river network to route process material continental source coastal zone. Mean TN (for mid‐1990s time period) is determined...
Nearly all freshwaters and coastal zones of the US are degraded from inputs excess reactive nitrogen (Nr), sources which runoff, atmospheric N deposition, imported food feed. Some major adverse effects include harmful algal blooms, hypoxia fresh waters, ocean acidification, long-term harm to human health, increased emissions greenhouse gases. Nitrogen fluxes areas nitrous oxide waters have in response inputs. Denitrification sedimentation organic sediments important processes that divert...
Water-level fluctuations due to reservoir management could substantially affect the timing and magnitude of methane (CH4) fluxes atmosphere. However, effects such on CH4 emissions have received limited attention. Here we examine emission dynamics in six Pacific Northwest U.S. reservoirs varying trophic status, morphometry, regimes. In these systems, show that water-level drawdowns can, at least temporarily, greatly increase per-area atmosphere, can account for more than 90% annual flux a...
Abstract Collectively, reservoirs constitute a significant global source of C‐based greenhouse gases (GHGs). Yet, estimates reservoir carbon dioxide (CO 2 ) and methane (CH 4 emissions remain uncertain, varying more than four‐fold in recent analyses. Here we present results from application the Greenhouse Gas Reservoirs (G‐res) model wherein estimate per‐area per‐reservoir CO CH fluxes, by specific flux pathway spatially temporally explicit manner, as function characteristics. We show: (a)...
Algal blooms increasingly threaten lake and reservoir water quality at the global scale, caused by ongoing climate change nutrient loading. To anticipate these algal blooms, models to project future worldwide are required. Here we present state-of-the-art in projection modelling explore requirements of an ideal model. Based on this, identify current challenges opportunities for such model development. Since most building blocks present, foresee that any earth can be developed near future....
Abstract Globally, there are millions of kilometres drainage ditches which have the potential to emit powerful greenhouse gas methane (CH 4 ), but these emissions not reported in budgets inland waters or drained lands. Here, we synthesise data show that spanning a global latitudinal gradient and across different land uses large quantities CH atmosphere. Area-specific comparable those from lakes, streams, reservoirs, wetlands. While it is generally assumed negates terrestrial emissions, find...
Summary Methanotrophic bacteria play a key role in limiting methane emissions from lakes. It is generally assumed that methanotrophic are mostly active at the oxic‐anoxic transition zone stratified lakes, where they use oxygen to oxidize methane. Here, we describe methanotroph of genera Methylobacter performing high‐rate (up 72 μM day −1 ) oxidation anoxic hypolimnion temperate Lacamas Lake (Washington, USA), stimulated by both nitrate and sulfate addition. Oxic incubations showed species,...
1. Anthropogenic-derived nutrient inputs to coastal environments have increased dramatically worldwide in the latter half of 20th century and are altering ecosystems. We evaluated effects nitrogen loading on changes macrophyte community structure associated fauna a north temperate estuary. found that shift primary producers from eelgrass macroalgae response alters habitat physical chemical food webs. As load we macroalgal biomass, decreased shoot density fish decapod abundance diversity. 2....