our research
Translation Ecology Grounded in a Field-Based Approach
Key research themes
1) Biogeochemistry of streams and rivers
2) Influence of agricultural land use and conservation on streams
3) Stream Restoration
4) Using experiments to quantify stream transport at ND-LEEF
2) Influence of agricultural land use and conservation on streams
3) Stream Restoration
4) Using experiments to quantify stream transport at ND-LEEF
Selected Research projects:
1. The effect of cover crops in reducing nutrient loss from agricultural fields and improve water quality
Funding: USDA Conservation Innovation Grant (CIG); start 9/12
Challenge: Channelized agricultural streams export excess nitrogen (N), phosphorus (P), and sediments to downstream ecosystems where they can contaminate drinking water, threaten sensitive species, and fuel harmful algal blooms. In the Midwest, excess fertilizer nutrients often enter streams via tile drains, especially during Winter and Spring when fields are normally bare. Subsurface tile drainage improves agricultural productivity by removing excess water from fields, but also facilitates the transport of fertilizer N and P, acting as “hotspots” of nutrient export.
How are we tackling this issue?
Challenge: Channelized agricultural streams export excess nitrogen (N), phosphorus (P), and sediments to downstream ecosystems where they can contaminate drinking water, threaten sensitive species, and fuel harmful algal blooms. In the Midwest, excess fertilizer nutrients often enter streams via tile drains, especially during Winter and Spring when fields are normally bare. Subsurface tile drainage improves agricultural productivity by removing excess water from fields, but also facilitates the transport of fertilizer N and P, acting as “hotspots” of nutrient export.
How are we tackling this issue?
- Cover crops, like ryegrass, can be planted after corn harvest, providing ground cover during Winter and Spring, when fields would normally be bare. Cover crops have the potential to reduce nutrient loss from tile drains by retaining nutrients on fields that would otherwise be lost during snowmelt and storms.
- We are conducting a watershed-scale experiment to isolate and quantify how shifting land use from bare soil to cover crops impacts nutrient export from tile drains to streams.
- We planted cover crops on 67% of the croppable acres in the Shatto Ditch Watershed (Kosciusko Co., IN) and are using a comprehensive sampling regime that allows us to determine how changing land cover (e.g., cover crops) impact both tile drain and in-stream nutrient export.
2. Pairing watershed-scale cover crops with the two-stage ditch to improve water quality in agricultural streams.
Funding: USDA Regional Conservation Partnership Program (RCPP); start 6/15
Challenge: During the past 150 years, the Midwestern US has undergone extensive land use change as vast wetlands and prairies have been converted to productive cropland. While these croplands have played a crucial role in feeding the country and the world, nutrient runoff from these fields has also significantly impaired adjacent stream water quality, threatened aquatic species, and jeopardized downstream habitats. Excess nutrients exported to sensitive downstream areas like Lake Erie and the Gulf of Mexico have been linked to recurring algal blooms and hypoxic “dead zones” causing ecological and economic problems.
How are we tackling this issue?
Goal: Our goal is to determine quantify the water quality benefits of “stacking” two complementary conservation practices, implemented at the watershed-scale, in two contrasting Indiana watersheds.
Challenge: During the past 150 years, the Midwestern US has undergone extensive land use change as vast wetlands and prairies have been converted to productive cropland. While these croplands have played a crucial role in feeding the country and the world, nutrient runoff from these fields has also significantly impaired adjacent stream water quality, threatened aquatic species, and jeopardized downstream habitats. Excess nutrients exported to sensitive downstream areas like Lake Erie and the Gulf of Mexico have been linked to recurring algal blooms and hypoxic “dead zones” causing ecological and economic problems.
How are we tackling this issue?
- We are pairing the watershed-scale implementation of winter cover crops and two-stage ditch to reduce nutrient leaching from fields to tile drains to streams.
- Cover crops reduce nutrient runoff by retaining fertilizer nutrients on fields, and preventing losses during snowmelt and storms.
- The two-stage ditch is an in-stream practice that transforms conventionally-managed, trapezoidal ditches into stable systems by constructing “mini” floodplains within the stream. These floodplains improve bank stability while reducing sediment and nutrient export.
Goal: Our goal is to determine quantify the water quality benefits of “stacking” two complementary conservation practices, implemented at the watershed-scale, in two contrasting Indiana watersheds.
3. Climate change and hydrology: The critical connection between greenhouse gas (GHG) emissions and the hyporheic zone at the stream network scale in two watersheds of contrasting land use
Funding: NSF Division of Earth Sciences (EAR); Start 5/14
Challenge: Previous research has shown that stream processing of reactive nitrogen, primarily bioavailable ammonium and nitrate, is a potentially important source of the potent GHG nitrous oxide (N2O), but few studies have measured GHG emissions at the stream-network scale, and in basins of contrasting land use.
How are we tackling this issue?
Goal: Our goal is to quantify the role of human land use on nitrogen processing at the stream/river network scale using a combination of novel field data and analytical-modeling simulations.
Challenge: Previous research has shown that stream processing of reactive nitrogen, primarily bioavailable ammonium and nitrate, is a potentially important source of the potent GHG nitrous oxide (N2O), but few studies have measured GHG emissions at the stream-network scale, and in basins of contrasting land use.
How are we tackling this issue?
- We are using a novel synoptic sampling regime in two Midwestern river basins, the Manistee River (MI) and the Tippecanoe River (IN), that have varying influence of agricultural land use (<17% and 82% of total area, respectively).
- Seasonally, we use a team-approach to collect water chemistry, dissolved gas samples, and physical site characteristics at 80 individual stream/river sites in each watershed in a 24 hour period, and we conduct this sampling seasonally.
- This large empirical dataset will parameterize a watershed-scale model designed to accurately predict the fate of reactive nitrogen, and greenhouse gas emissions across basins of varying land use.
Goal: Our goal is to quantify the role of human land use on nitrogen processing at the stream/river network scale using a combination of novel field data and analytical-modeling simulations.
4. Monitoring the dispersal of genetically engineered organisms and their byproducts using Light Transmission Spectroscopy
Funding: USDA Biotechnology Risk Assessment Grants (BRAG); start 9/13
Challenge: Understanding and monitoring the dispersal of genetically engineered (GE) organisms (e.g., AquaAdvantage salmon) is a critical component of the safe and responsible use of transgenic technology in the environment. However, we currently lack the ability to rapidly and adequately track the movement of GE organisms in the environment, even though research has demonstrated that they can escape their intended range and disperse throughout river networks.
How are we tackling this issue?
Challenge: Understanding and monitoring the dispersal of genetically engineered (GE) organisms (e.g., AquaAdvantage salmon) is a critical component of the safe and responsible use of transgenic technology in the environment. However, we currently lack the ability to rapidly and adequately track the movement of GE organisms in the environment, even though research has demonstrated that they can escape their intended range and disperse throughout river networks.
How are we tackling this issue?
- Environmental DNA (eDNA) techniques have been successfully used to “fingerprint” invasive species (e.g., Asian carp) in aquatic environments. We will use eDNA techniques to detect the presence of GE organisms by developing new markers for GE organisms, such as the AquaAdvantage salmon.
- Additionally, we will develop a field-based detection technique for GE-eDNA by adapting novel Light Transmission Spectroscopy (LTS) technologies, which have shown promise for DNA-based detection of aquatic invasive species.
- LTS can measure the size, shape, and number of nanoparticles suspended in water, in real-time. We will modify for target species detection by measuring nanoparticles that specifically bind to target species DNA.
5. Linking improved soil health to water quality via the planting of cover crops in the Shatto Ditch Watershed, Kosciusko Co, IN.
Funding: Indiana Water Resources Research Center; start 3/14
Problem: Agricultural watersheds in the Midwestern US underwent extensive change when artificial tile drainage systems and increased availability of synthetic fertilizers became ubiquitous in the early 1900s. These changes have had enormous positive impacts on the agricultural economy and the expansion of agricultural exports. However, intensive cropland activity contributes to soil quality degradation and excess runoff of nutrients from agriculture fields that result in water quality problems including contaminated drinking water, algal blooms, and associated periods of hypoxia in receiving waters.
How are we tackling this issue?
Problem: Agricultural watersheds in the Midwestern US underwent extensive change when artificial tile drainage systems and increased availability of synthetic fertilizers became ubiquitous in the early 1900s. These changes have had enormous positive impacts on the agricultural economy and the expansion of agricultural exports. However, intensive cropland activity contributes to soil quality degradation and excess runoff of nutrients from agriculture fields that result in water quality problems including contaminated drinking water, algal blooms, and associated periods of hypoxia in receiving waters.
How are we tackling this issue?
- Conservation practices, like the planting of cover crops, improve soil health while reducing nutrient and sediment export from agricultural fields.
- Specifically, cover crops, planted after cash crop harvest, reduce soil erosion, decrease soil compaction, increase soil organic matter, and suppress weed growth.
- Increased uptake by cover crops of residual soil nitrogen and phosphorus during the winter and spring, when fields are normally bare, also reduces nutrient concentrations in the soil and potentially reduces leaching to streams.
- We are implementing watershed-scale planting of winter cover crops in two Indiana watersheds to determine the effects on soil nutrient content and nutrient leaching to tile drains, sampling soils year-round (including winter and spring) when we have observed the highest nutrient export.