James Larson
Science and Products
Temperature and invertebrate community composition at nearshore Great Lakes sites, 2013-2016
Data on ambient water temperatures and invertebrate community composition from ~40 sites in the western basin of Lake Erie, Saginaw Bay (Lake Huron), Grand Traverse Bay (Lake Michigan) and Green Bay (Lake Michigan). These samples were collected as part of a study on spatial variation in ecosystem processes.
Code associated with analysis and modeling of benthic and pelagic inorganic nutrient processing rates at the interface between a river and lake
In this data release the authors have code and 'data' that are used to model how sediment flux and water column processing of soluble reactive phosphorus (SRP), ammonium (NH4/NHX) and nitrate (NOX).
The file 'README.md' contains background information on how to access and use the data and code files.
Data Release Sediment and water column flux data from the Fox Rivermouth (Green Bay, WI; 2017)
These are data associated with water column incubation experiments performed in the Fox rivermouth. The Fox River is a Lake Michigan tributary that enters Green Bay. These experiments are used to measure the transformation of inorganic and total dissolved nutrients occurring in the surface water of the rivermouth. Experiments had light and dark treatments, and some experiments were paired with
Mercury and water level fluctuations in lakes of northern Minnesota - sampling site land cover and inundated area data
These data tables summarize land cover classifications, slope measurements, and inundated area estimates for several lakes in northern Minnesota, as part of a larger project seeking to identify associations between young-of-year Yellow Perch mercury content and water level metrics, temperature, and annual deposition data in a multivariate analysis. One table presents inundated area estimates for a
Data for dam passage analysis of bigheaded carps in Pools 15-19 of the upper Mississippi River during 2014-2017
Acoustic telemetry data (Vemco, Inc) were collected on invasive silver carp (Hypophthalmichthys molitrix), bighead carp (H. nobilis) and their hybrids in the upper Mississippi River (navigation pools 15-19) to determine movement patterns and preferred habitats during September 2013 through November 2017. We consolidated these data into intervals of fish within-pool residency and intervals of fish
Hydrogeochemical mixing data from Lake Michigan tributaries 2011
This dataset describes the hydrogeomorphic structure and lake-tributary mixing in three intermediate-sized Lake Michigan rivermouths: Ford River, Manitowoc River, and Pere Marquette River. Data were collected from May to October 2011. Water chemistry variables were measured with a multiparameter sonde along longitudinal, lateral, and vertical transects. Magnesium, boron, and stable water isotope c
Ecological Process Monitoring in the Western Basin Lake Erie, 2013.
This dataset includes information collected from “ecological process monitoring stations� located across the western basin of Lake Erie (originating at the Maumee River and reaching as far east as the Bass Islands). Nine worksheets are included in this file, of which 1 is a meta-data sheet that describes the variab
Filter Total Items: 38
Episodic nutrient addition affects water column nutrient processing rates in river-to-lake transitional zones
Storm-driven nutrient loading from tributaries can fuel eutrophication in nearshore and open water areas of lentic ecosystems. However, nutrient processing in river-to-lake transitional zones can substantially alter the amount and composition of nutrients transported to lakes from upstream surface waters. We measured the removal of nutrients and dissolved organic carbon (DOC) from the water column
Timing and hydrological conditions associated with bigheaded carp movement past navigation dams on the upper Mississippi river
As the range of non-native bigheaded carps (Hypophthalmichthys spp.) continues to expand throughout river systems of the United States, managers are tasked with preventing or slowing the spread of these invasive species. Main stem navigation dams on the upper Mississippi River, long considered a deterrent to fish migration, may slow or prevent the spread of invasive fish species. As discharge incr
Benthic and planktonic inorganic nutrient processing rates at the interface between a river and lake
The interface between lotic and lentic ecosystems is often a zone of intense metabolic activity, as primary production in streams and rivers can be light limited whereas nutrients often limit primary production in lake ecosystems. Our objective was to model the influence that rivermouths (the lotic-lentic interface) could have on the loads of soluble reactive phosphorus (SRP) and dissolved inorgan
Mercury and water level management in lakes of northern Minnesota
Water level (WL) fluctuations substantially alter the fauna, flora, and microbial community of nearshore aquatic ecosystems. Water level management therefore has the potential to strongly influence a wide variety of ecosystem processes. Many northern temperate lake food webs experience substantial methylmercury contamination, which is partially mediated by the action of sulfate-reducing bacteria o
Stoichiometric ecotoxicology for a multisubstance world
Nutritional and contaminant stressors influence organismal physiology, trophic interactions, community structure, and ecosystem-level processes; however, the interactions between toxicity and elemental imbalance in food resources have been examined in only a few ecotoxicity studies. Integrating well-developed ecological theories that cross all levels of biological organization can enhance our unde
Land use effects on sediment nutrient processes in a heavily modified watershed using structural equation models
Contemporary land use can affect sediment nutrient processes in rivers draining heavily modified watersheds; however, studies linking land use to sediment nutrient processes in large river networks are limited. In this study, we developed and evaluated structural equation models (SE models) for denitrification and phosphorus retention capacity to determine direct and indirect linkages between curr
Preliminary analysis to estimate the spatial distribution of benefits of P load reduction: Identifying the spatial influence of phosphorus loading from the Maumee River (USA) in western Lake Erie
Since the early 2000s, Lake Erie has been experiencing annual cyanobacterial blooms that often cover large portions of the western basin and even reach into the central basin. These blooms have affected several ecosystem services provided by Lake Erie to surrounding communities (notably drinking water quality). Several modeling efforts have identified the springtime total bioavailable phosphorus (
Phosphorus, nitrogen and dissolved organic carbon fluxes from sediments in freshwater rivermouths entering Green Bay (Lake Michigan; USA)
Transitional areas between ecosystem types are often active biogeochemically due to resource limitation changes. Lotic-to-lentic transitions in freshwaters appear active biogeochemically, but few studies have directly measured nutrient processing rates to assess whether processing within the rivermouth is important for load estimates or the local communities. We measured oxic fluxes of inorganic n
Estimating the degree to which distance and temperature differences drive changes in fish community composition over time in the upper Mississippi River
Similarity in community composition declines as distance between locations increases, a phenomenon that has been observed in a wide variety of freshwater, marine and terrestrial ecosystems. One driver of the distance-similarity relationship is the presence of environmental gradients that alter the suitability of sites for particular species. Although some environmental gradients, such as geology
Influence of a high-head dam as a dispersal barrier to fish community structure of the Upper Mississippi River
In river systems, high‐head dams may increase the distance‐decay of fish community similarity by creating nearly impermeable dispersal barriers to certain species from upstream reaches. Substantial evidence suggests that migratory species are impacted by dams, and most previous studies in stream/river networks have focused on small streams and headwaters. Here, we assess whether a high‐head dam (L
Seasonal patterns in hydrochemical mixing in three Great Lakes rivermouth ecosystems
Rivermouth ecosystems in the Laurentian Great Lakes represent complex hydrologic mixing zones where lake and river water combine to form biologically productive areas that are functionally similar to marine estuaries. As urban, industrial, shipping, and recreational centers, rivermouths are the focus of human interactions with the Great Lakes and, likewise, may represent critical habitat for larva
Precipitation and temperature drive continental scale patterns in stream invertebrate production
Secondary production, the growth of new heterotrophic biomass, is a key process in aquatic and terrestrial ecosystems that has been carefully measured in many flowing water ecosystems. We combine structural equation modeling with the first worldwide dataset on annual secondary production of stream invertebrate communities to reveal core pathways linking air temperature and precipitation to seconda
Science and Products
- Data
Temperature and invertebrate community composition at nearshore Great Lakes sites, 2013-2016
Data on ambient water temperatures and invertebrate community composition from ~40 sites in the western basin of Lake Erie, Saginaw Bay (Lake Huron), Grand Traverse Bay (Lake Michigan) and Green Bay (Lake Michigan). These samples were collected as part of a study on spatial variation in ecosystem processes.Code associated with analysis and modeling of benthic and pelagic inorganic nutrient processing rates at the interface between a river and lake
In this data release the authors have code and 'data' that are used to model how sediment flux and water column processing of soluble reactive phosphorus (SRP), ammonium (NH4/NHX) and nitrate (NOX). The file 'README.md' contains background information on how to access and use the data and code files.Data Release Sediment and water column flux data from the Fox Rivermouth (Green Bay, WI; 2017)
These are data associated with water column incubation experiments performed in the Fox rivermouth. The Fox River is a Lake Michigan tributary that enters Green Bay. These experiments are used to measure the transformation of inorganic and total dissolved nutrients occurring in the surface water of the rivermouth. Experiments had light and dark treatments, and some experiments were paired withMercury and water level fluctuations in lakes of northern Minnesota - sampling site land cover and inundated area data
These data tables summarize land cover classifications, slope measurements, and inundated area estimates for several lakes in northern Minnesota, as part of a larger project seeking to identify associations between young-of-year Yellow Perch mercury content and water level metrics, temperature, and annual deposition data in a multivariate analysis. One table presents inundated area estimates for aData for dam passage analysis of bigheaded carps in Pools 15-19 of the upper Mississippi River during 2014-2017
Acoustic telemetry data (Vemco, Inc) were collected on invasive silver carp (Hypophthalmichthys molitrix), bighead carp (H. nobilis) and their hybrids in the upper Mississippi River (navigation pools 15-19) to determine movement patterns and preferred habitats during September 2013 through November 2017. We consolidated these data into intervals of fish within-pool residency and intervals of fishHydrogeochemical mixing data from Lake Michigan tributaries 2011
This dataset describes the hydrogeomorphic structure and lake-tributary mixing in three intermediate-sized Lake Michigan rivermouths: Ford River, Manitowoc River, and Pere Marquette River. Data were collected from May to October 2011. Water chemistry variables were measured with a multiparameter sonde along longitudinal, lateral, and vertical transects. Magnesium, boron, and stable water isotope cEcological Process Monitoring in the Western Basin Lake Erie, 2013.
This dataset includes information collected from “ecological process monitoring stations� located across the western basin of Lake Erie (originating at the Maumee River and reaching as far east as the Bass Islands). Nine worksheets are included in this file, of which 1 is a meta-data sheet that describes the variab - Publications
Filter Total Items: 38
Episodic nutrient addition affects water column nutrient processing rates in river-to-lake transitional zones
Storm-driven nutrient loading from tributaries can fuel eutrophication in nearshore and open water areas of lentic ecosystems. However, nutrient processing in river-to-lake transitional zones can substantially alter the amount and composition of nutrients transported to lakes from upstream surface waters. We measured the removal of nutrients and dissolved organic carbon (DOC) from the water columnTiming and hydrological conditions associated with bigheaded carp movement past navigation dams on the upper Mississippi river
As the range of non-native bigheaded carps (Hypophthalmichthys spp.) continues to expand throughout river systems of the United States, managers are tasked with preventing or slowing the spread of these invasive species. Main stem navigation dams on the upper Mississippi River, long considered a deterrent to fish migration, may slow or prevent the spread of invasive fish species. As discharge incrBenthic and planktonic inorganic nutrient processing rates at the interface between a river and lake
The interface between lotic and lentic ecosystems is often a zone of intense metabolic activity, as primary production in streams and rivers can be light limited whereas nutrients often limit primary production in lake ecosystems. Our objective was to model the influence that rivermouths (the lotic-lentic interface) could have on the loads of soluble reactive phosphorus (SRP) and dissolved inorganMercury and water level management in lakes of northern Minnesota
Water level (WL) fluctuations substantially alter the fauna, flora, and microbial community of nearshore aquatic ecosystems. Water level management therefore has the potential to strongly influence a wide variety of ecosystem processes. Many northern temperate lake food webs experience substantial methylmercury contamination, which is partially mediated by the action of sulfate-reducing bacteria oStoichiometric ecotoxicology for a multisubstance world
Nutritional and contaminant stressors influence organismal physiology, trophic interactions, community structure, and ecosystem-level processes; however, the interactions between toxicity and elemental imbalance in food resources have been examined in only a few ecotoxicity studies. Integrating well-developed ecological theories that cross all levels of biological organization can enhance our undeLand use effects on sediment nutrient processes in a heavily modified watershed using structural equation models
Contemporary land use can affect sediment nutrient processes in rivers draining heavily modified watersheds; however, studies linking land use to sediment nutrient processes in large river networks are limited. In this study, we developed and evaluated structural equation models (SE models) for denitrification and phosphorus retention capacity to determine direct and indirect linkages between currPreliminary analysis to estimate the spatial distribution of benefits of P load reduction: Identifying the spatial influence of phosphorus loading from the Maumee River (USA) in western Lake Erie
Since the early 2000s, Lake Erie has been experiencing annual cyanobacterial blooms that often cover large portions of the western basin and even reach into the central basin. These blooms have affected several ecosystem services provided by Lake Erie to surrounding communities (notably drinking water quality). Several modeling efforts have identified the springtime total bioavailable phosphorus (Phosphorus, nitrogen and dissolved organic carbon fluxes from sediments in freshwater rivermouths entering Green Bay (Lake Michigan; USA)
Transitional areas between ecosystem types are often active biogeochemically due to resource limitation changes. Lotic-to-lentic transitions in freshwaters appear active biogeochemically, but few studies have directly measured nutrient processing rates to assess whether processing within the rivermouth is important for load estimates or the local communities. We measured oxic fluxes of inorganic nEstimating the degree to which distance and temperature differences drive changes in fish community composition over time in the upper Mississippi River
Similarity in community composition declines as distance between locations increases, a phenomenon that has been observed in a wide variety of freshwater, marine and terrestrial ecosystems. One driver of the distance-similarity relationship is the presence of environmental gradients that alter the suitability of sites for particular species. Although some environmental gradients, such as geologyInfluence of a high-head dam as a dispersal barrier to fish community structure of the Upper Mississippi River
In river systems, high‐head dams may increase the distance‐decay of fish community similarity by creating nearly impermeable dispersal barriers to certain species from upstream reaches. Substantial evidence suggests that migratory species are impacted by dams, and most previous studies in stream/river networks have focused on small streams and headwaters. Here, we assess whether a high‐head dam (LSeasonal patterns in hydrochemical mixing in three Great Lakes rivermouth ecosystems
Rivermouth ecosystems in the Laurentian Great Lakes represent complex hydrologic mixing zones where lake and river water combine to form biologically productive areas that are functionally similar to marine estuaries. As urban, industrial, shipping, and recreational centers, rivermouths are the focus of human interactions with the Great Lakes and, likewise, may represent critical habitat for larvaPrecipitation and temperature drive continental scale patterns in stream invertebrate production
Secondary production, the growth of new heterotrophic biomass, is a key process in aquatic and terrestrial ecosystems that has been carefully measured in many flowing water ecosystems. We combine structural equation modeling with the first worldwide dataset on annual secondary production of stream invertebrate communities to reveal core pathways linking air temperature and precipitation to seconda