A5062794094- Fish Ecology and Management Studies
- Aquatic Ecosystems and Phytoplankton Dynamics
- Soil and Water Nutrient Dynamics
- Freshwater macroinvertebrate diversity and ecology
- Marine and coastal ecosystems
- Water Quality and Pollution Assessment
- Hydrology and Watershed Management Studies
- Hydrology and Sediment Transport Processes
- Aquatic Invertebrate Ecology and Behavior
- Environmental DNA in Biodiversity Studies
- Species Distribution and Climate Change
- Flood Risk Assessment and Management
- Coastal wetland ecosystem dynamics
- Soil erosion and sediment transport
- Coal and Its By-products
- Marine Biology and Ecology Research
- Smart Materials for Construction
- Mine drainage and remediation techniques
- Heavy metals in environment
- Environmental Toxicology and Ecotoxicology
- Coastal and Marine Management
- Toxic Organic Pollutants Impact
- Aquatic Ecosystems and Biodiversity
- Peatlands and Wetlands Ecology
- Ecology and biodiversity studies
Environmental Protection Agency
2014-2024
District of Columbia Water and Sewer Authority
2017-2022
National Center for Environmental Assessment (EPA)
2009-2012
University of Wisconsin–Madison
2004-2005
Wright State University
1998
We describe continental-scale increases in lake and stream total phosphorus (TP) concentrations, identified through periodic probability surveys of thousands water bodies the conterminous U.S. The increases, observed over period 2000-2014 were most notable sites relatively undisturbed catchments where TP was initially low (e.g., less than 10 μg L(-1)). Nationally, percentage length with ≤ L(-1) decreased from 24.5 to 10.4 1.6% 2004 2009 2014; lakes 24.9 6.7% between 2007 2012. Increasing...
Abstract Lakes process terrigenous carbon. The carbon load processed by lakes may partially offset estimates made for terrestrial net ecosystem exchange ( NEE ). balance within between burial and evasion to the atmosphere determines whether are sinks or sources of atmospheric Here we develop a model study processing both autochthonous allochthonous in lakes. We run over gradients dissolved organic DOC ) total phosphorus TP concentrations found Northern Highlands Lake District Wisconsin. In...
The linkage of trait responses to stressor gradients has potential expand biomonitoring approaches beyond traditional taxonomically based assessments that identify ecological effect provide a causal diagnosis. Traits-based information may have several advantages over methods. These include providing mechanistic linkages biotic environmental conditions, consistent descriptors or metrics across broad spatial scales, more seasonal stability compared with taxonomic measures, and seamless...
Abstract Understanding the factors that affect water quality and ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how will respond to changes not only requires data, but also information about context of individual bodies across broad spatial extents. Because lake usually sampled in limited geographic regions, often for time periods, assessing controls compilation many data sets regions into integrated database. LAGOS-NE accomplishes...
Abstract Elevated allochthonous inputs of organic matter are increasingly recognized as a driver ecosystem change in lakes, particularly when concurrent with eutrophication. Evaluation lakes nutrient‐color paradigm (i.e., based on total phosphorus and true color) enables more robust approach to research management. To assess temporal spatial patterns status for U.S. associated food web attributes, we analyzed the Environmental Protection Agency's National Lakes Assessment (NLA) data. With...
Abstract Lake trophic state is a key ecosystem property that integrates lake’s physical, chemical, and biological processes. Despite the importance of as gauge lake water quality, standardized machine-readable observations are uncommon. Remote sensing presents an opportunity to detect analyze with reproducible, robust methods across time space. We used Landsat surface reflectance data create first compendium annual for 55,662 lakes at least 10 ha in area throughout contiguous United States...
Abstract There has been limited research on the abiotic and biotic factors affecting prevalence of phago-mixotrophy (prevMixo) among nanophytoplankton across freshwater ecosystems. In recent years, large-scale sampling campaigns like EPA-National Lakes Assessment NSERC LakePulse survey have generated surface water community composition data for hundreds lakes North America, covering large environmental gradients. We present results from our analyses these two surveys, focusing a taxonomic...
Abstract Streams, riparian areas, floodplains, alluvial aquifers, and downstream waters (e.g., large rivers, lakes, oceans) are interconnected by longitudinal, lateral, vertical fluxes of water, other materials, energy. Collectively, these called fluvial hydrosystems. Physical chemical connectivity within hydrosystems is created the transport nonliving materials sediment, nutrients, contaminants) which either do or not chemically change (chemical physical connections, respectively). A...
Freshwater ecosystems are linked at various spatial and temporal scales by movements of biota adapted to life in water. We review the literature on aquatic organisms that connect different types freshwater habitats, focusing linkages from streams wetlands downstream waters. Here, streams, wetlands, rivers, lakes, ponds, other habitats viewed as dynamic ecosystem mosaics (FEMs) collectively provide resources needed sustain life. Based existing evidence, it is clear biotic throughout FEMs have...
Summary The occurrence of high cyanotoxin concentrations can severely impair the use a waterbody for drinking water and recreational purposes. Cyanotoxins are likely to occur under specific environmental conditions, so identifying these conditions facilitate management reduce likelihood concentrations. We analysed data collected from lakes across contiguous United States identify variables that strongly associated with common cyanotoxin, microcystin ( MC ). Since many different covary , we...
Abstract The relationship between zooplankton biomass and phytoplankton can provide insight into the structure function of lake biological communities. We used a Bayesian network model to analyze continental‐scale data set estimate changes in ( Z ) P biomasses along eutrophication gradient. allowed us combine two different measurements (chlorophyll concentration directly observed biovolume) improve precision estimates true within each sample. also separate relationships abundance mean...
Summary 1. The use of species traits to interpret biological changes in invertebrate assemblages across environmental gradients has been suggested as a method improve discrimination over existing composition methods. One reason for greater potential and predictive ability is the assumed universality range spatial temporal scales. We explore this assumption by comparing consistency stressor–response relationships trait characteristic (percent clinging taxa) common taxonomy‐based metric...
Lake water levels are integral to lake function, but hydrologic changes from land and management may alter fluctuations beyond natural ranges. We constructed a conceptual model of multifaceted drivers water-levels evaporation-to-inflow ratio (Evap:Inflow). Using structural equation modeling framework, we tested our on 1) national subset lakes in the conterminous United States with minimal describe hydrology 2) five ecoregional subsets explore regional variation effects. Our fit datasets...
Ecosystem-based disaster risk reduction (eco-DRR) exemplifies the transformative potential of nature-based solutions (NBS) by bringing together reduction, climate adaptation, and human development needs. As a cornerstone NBS, eco-DRR leverages sustainable use, restoration, conservation ecosystems to reduce risks while enhancing ecological social resilience. Beyond physical hazard mitigation, addresses sources vulnerability improving food water security, diversifying livelihoods, fostering...
Abstract Connectivity is a fundamental but highly dynamic property of watersheds. Variability in the types and degrees aquatic ecosystem connectivity presents challenges for researchers managers seeking to accurately quantify its effects on critical hydrologic, biogeochemical, biological processes. However, protecting natural gradients key range services that ecosystems provide. In this featured collection, we review available evidence connections functions by which streams wetlands affect...
Abstract While there are many local and regional sampling efforts in lakes across the U.S., it is often difficult to compile this information into a cohesive framework make national‐ or continental‐scale conclusions. To address gap, U.S. Environmental Protection Agency partners with States Tribes implement National Lakes Assessment, which national‐scale, coordinated lake program. The resulting data include colocated biological, chemical, habitat, human use measures that available scientific...
We describe a collection of aquatic and wetland habitats in an inland landscape, their occurrence within terrestrial matrix, as "freshwater ecosystem mosaic" (FEM). Aquatic any FEM can vary widely, from permanently ponded lakes, to ephemerally wetlands, groundwater-fed springs, flowing rivers streams. The matrix also vary, including its influence on flows energy, materials, organisms among ecosystems. Biota occurring specific region are adapted the unique opportunities challenges presented...
Abstract Establishing baseline hydrologic characteristics for lakes in the United States (U.S.) is critical to evaluate changes lake hydrology. We used U.S. Environmental Protection Agency National Lakes Assessment 2007 and 2012 surveys assess of a population ~45,000 conterminous based on probability samples ~1,000 lakes/yr distributed across nine ecoregions. Lake study variables include water‐level drawdown (i.e., vertical decline horizontal littoral exposure) two water stable...
Quantitative models that predict cyanotoxin concentrations in lakes and reservoirs from nutrient would facilitate management of these resources for recreation as sources drinking water. Development field data has been hampered by the high proportion samples which are below detection limits variability within individual lakes. Here, we describe a national-scale hierarchical Bayesian model addresses issues predicts microcystin summer mean total nitrogen phosphorus concentrations. This accounts...
Lakes face multiple anthropogenic pressures that can substantially alter their hydrology. Dams and land use in the watershed (e.g., irrigated agriculture) modify lake water regimes beyond natural ranges, changing climate may exacerbate stresses on However, we lack cost-effective indicators to quantify hydrologic alteration potential lakes at regional national extents. We developed a framework rank by for dams hydrology (HydrAP) be applied scale. The HydrAP principles are 1) primary drivers...
Changes in phosphorus concentrations affect periphytic diatom composition streams, yet we rarely observe strong relationships between richness and phosphorus. In contrast, changes conductivity are strongly associated with differences both richness. We hypothesised that could better understand the mechanisms control phosphorus-richness relationship by examining occurrence of individual taxa, comparing these taxon occurrence, documenting how niche breadths taxa patterns. estimated using DNA...