Stephen Kalkhoff (Former Employee)
Science and Products
Filter Total Items: 70
Herbicides and herbicide degradation products in upper midwest agricultural streams during august base-flow conditions Herbicides and herbicide degradation products in upper midwest agricultural streams during august base-flow conditions
Herbicide concentrations in streams of the U.S. Midwest have been shown to decrease through the growing season due to a variety of chemical and physical factors. The occurrence of herbicide degradation products at the end of the growing season is not well known. This study was conducted to document the occurrence of commonly used herbicides and their degradation products in Illinois...
Authors
S. J. Kalkhoff, K. Lee, S. Porter, P. Terrio, E.M. Thurman
It's not just how high; it's how clean: Sampling the spring 2001 flood in the Upper Mississippi River Basin It's not just how high; it's how clean: Sampling the spring 2001 flood in the Upper Mississippi River Basin
Floods can cause water-quality problems because of the large amounts of contaminants (sediment, nutrients, pesticides, and bacteria) that can be transported by floodwaters. during the flood on the Upper Mississippi River in 2001, water-quality and water-quality data were collected during near-record streamflow. This is the first time that samples for determining organic wastewater...
Authors
Glenn Patterson, Dana Kolpin, Stephen Kalkhoff, Kathy Lee, Douglas Schnoebelen, Kimberlee K. Barnes, Richard Coupe
Occurrence and distribution of pesticides in streams of the Eastern Iowa Basins, 1996-98 Occurrence and distribution of pesticides in streams of the Eastern Iowa Basins, 1996-98
The U.S. Geological Survey began collection of water samples in streams of the Eastern Iowa Basins in 1996 for the analysis of pesticides and pesticide degradates as part of the National Water Quality Assessment Program (NAWQA). This study provides some of the first large scale monitoring data on pesticides and pesticide degradates in Eastern Iowa. Three hundred and forty-four samples...
Authors
Douglas Schnoebelen, Stephen Kalkhoff, Kent Becher
The occurrence of chloroacetanilide and triazine herbicide degradates in streams in eastern Iowa The occurrence of chloroacetanilide and triazine herbicide degradates in streams in eastern Iowa
No abstract available.
Authors
Stephen Kalkhoff, Douglas Schnoebelen, Earl Michael Thurman
Water quality in the eastern Iowa basins Water quality in the eastern Iowa basins
This article summarizes major findings about nutrients in surface and groundwater in the eastern Iowa basins (see map) between 1996 and 1998. The data were collected as part of the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA). Water quality is discussed in terms of local and regional issues and compared with conditions found in all 36 National NAWQA...
Authors
Stephen Kalkhoff, Kimberlee Barnes, Kent Becher, Mark Savoca, Douglas Schnoebelen, Eric Sadorf, Stephen Porter, Daniel Sullivan, John Creswell
Water-quality assessment of the eastern Iowa basins– Nitrogen, phosphorus, suspended sediment, and organic carbon in surface water, 1996–98 Water-quality assessment of the eastern Iowa basins– Nitrogen, phosphorus, suspended sediment, and organic carbon in surface water, 1996–98
Twelve sites on streams and rivers in the Eastern Iowa Basins study unit were sampled monthly and during selected storm events from March 1996 through September 1998 to assess the occurrence, distribution, and transport of nitrogen, phosphorus, suspended sediment, and organic carbon as part of the U.S. Geological Survey’s National Water-Quality Assessment Program. One site was dropped...
Authors
Kent Becher, Stephen Kalkhoff, Douglas Schnoebelen, Kimberlee K. Barnes, Von Miller
Influence of natural factors on the quality of midwestern streams and rivers Influence of natural factors on the quality of midwestern streams and rivers
Streams flowing through cropland in the Midwestern Corn Belt differ considerably in their chemical and ecological characteristics, even though agricultural land use is highly intensive throughout the entire region. These differences likely are attributable to differences in riparian vegetation, soil properties, and hydrology. This conclusion is based on results from a study of the upper...
Authors
Stephen Porter, Mitchell Harris, Stephen Kalkhoff
Summary of the major water-quality findings from the Eastern Iowa Basins study unit of the National Water-Quality Assessment Program Summary of the major water-quality findings from the Eastern Iowa Basins study unit of the National Water-Quality Assessment Program
An integrated assessment of the water quality in streams and aquifers in the Wapsipinicon, Iowa, Cedar, and Skunk River basins was conducted in 1996 through 1998 as part of the Eastern Iowa Basins (EIWA) study unit of the U.S. Geological Survey's National Water-Quality Assessment Program (NAWQA). The EIWA study unit is one of 59 study units across the Nation designed to assess the status...
Authors
Stephen Kalkhoff
Major ground-water findings from the National Water-Quality Assessment Program (NAWQA) in Iowa Major ground-water findings from the National Water-Quality Assessment Program (NAWQA) in Iowa
No abstract available.
Authors
Stephen Kalkhoff
Water quality in the eastern Iowa basins, Iowa and Minnesota, 1996-98 Water quality in the eastern Iowa basins, Iowa and Minnesota, 1996-98
The water quality in rivers and streams and in selected aquifers in eastern Iowa and part of southern Minnesota is described and illustrated. Major ions, nitrogen and other nutrients, and pesticides and some of their breakdown compounds were analyzed in both surface and ground water. Biological communities that included fish, invertebrates, and algae, were described in relation to stream...
Authors
Stephen Kalkhoff, Kimberlee K. Barnes, Kent Becher, Mark Savoca, Douglas Schnoebelen, Eric Sadorf, Stephen Porter, Daniel Sullivan
Occurrence of acetochlor and acetochlor metabolites in alluvial aquifers in Iowa Occurrence of acetochlor and acetochlor metabolites in alluvial aquifers in Iowa
No abstract available.
Authors
Stephen Kalkhoff, Mark Savoca, Eric Sadorf, Dana Kolpin, Earl Thurman
Occurrence and distribution of chloroacetanilide and triazine pesticide metabolites in streams in eastern Iowa Occurrence and distribution of chloroacetanilide and triazine pesticide metabolites in streams in eastern Iowa
No abstract available.
Authors
Stephen Kalkhoff, E.M. Thurman
Science and Products
Filter Total Items: 70
Herbicides and herbicide degradation products in upper midwest agricultural streams during august base-flow conditions Herbicides and herbicide degradation products in upper midwest agricultural streams during august base-flow conditions
Herbicide concentrations in streams of the U.S. Midwest have been shown to decrease through the growing season due to a variety of chemical and physical factors. The occurrence of herbicide degradation products at the end of the growing season is not well known. This study was conducted to document the occurrence of commonly used herbicides and their degradation products in Illinois...
Authors
S. J. Kalkhoff, K. Lee, S. Porter, P. Terrio, E.M. Thurman
It's not just how high; it's how clean: Sampling the spring 2001 flood in the Upper Mississippi River Basin It's not just how high; it's how clean: Sampling the spring 2001 flood in the Upper Mississippi River Basin
Floods can cause water-quality problems because of the large amounts of contaminants (sediment, nutrients, pesticides, and bacteria) that can be transported by floodwaters. during the flood on the Upper Mississippi River in 2001, water-quality and water-quality data were collected during near-record streamflow. This is the first time that samples for determining organic wastewater...
Authors
Glenn Patterson, Dana Kolpin, Stephen Kalkhoff, Kathy Lee, Douglas Schnoebelen, Kimberlee K. Barnes, Richard Coupe
Occurrence and distribution of pesticides in streams of the Eastern Iowa Basins, 1996-98 Occurrence and distribution of pesticides in streams of the Eastern Iowa Basins, 1996-98
The U.S. Geological Survey began collection of water samples in streams of the Eastern Iowa Basins in 1996 for the analysis of pesticides and pesticide degradates as part of the National Water Quality Assessment Program (NAWQA). This study provides some of the first large scale monitoring data on pesticides and pesticide degradates in Eastern Iowa. Three hundred and forty-four samples...
Authors
Douglas Schnoebelen, Stephen Kalkhoff, Kent Becher
The occurrence of chloroacetanilide and triazine herbicide degradates in streams in eastern Iowa The occurrence of chloroacetanilide and triazine herbicide degradates in streams in eastern Iowa
No abstract available.
Authors
Stephen Kalkhoff, Douglas Schnoebelen, Earl Michael Thurman
Water quality in the eastern Iowa basins Water quality in the eastern Iowa basins
This article summarizes major findings about nutrients in surface and groundwater in the eastern Iowa basins (see map) between 1996 and 1998. The data were collected as part of the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA). Water quality is discussed in terms of local and regional issues and compared with conditions found in all 36 National NAWQA...
Authors
Stephen Kalkhoff, Kimberlee Barnes, Kent Becher, Mark Savoca, Douglas Schnoebelen, Eric Sadorf, Stephen Porter, Daniel Sullivan, John Creswell
Water-quality assessment of the eastern Iowa basins– Nitrogen, phosphorus, suspended sediment, and organic carbon in surface water, 1996–98 Water-quality assessment of the eastern Iowa basins– Nitrogen, phosphorus, suspended sediment, and organic carbon in surface water, 1996–98
Twelve sites on streams and rivers in the Eastern Iowa Basins study unit were sampled monthly and during selected storm events from March 1996 through September 1998 to assess the occurrence, distribution, and transport of nitrogen, phosphorus, suspended sediment, and organic carbon as part of the U.S. Geological Survey’s National Water-Quality Assessment Program. One site was dropped...
Authors
Kent Becher, Stephen Kalkhoff, Douglas Schnoebelen, Kimberlee K. Barnes, Von Miller
Influence of natural factors on the quality of midwestern streams and rivers Influence of natural factors on the quality of midwestern streams and rivers
Streams flowing through cropland in the Midwestern Corn Belt differ considerably in their chemical and ecological characteristics, even though agricultural land use is highly intensive throughout the entire region. These differences likely are attributable to differences in riparian vegetation, soil properties, and hydrology. This conclusion is based on results from a study of the upper...
Authors
Stephen Porter, Mitchell Harris, Stephen Kalkhoff
Summary of the major water-quality findings from the Eastern Iowa Basins study unit of the National Water-Quality Assessment Program Summary of the major water-quality findings from the Eastern Iowa Basins study unit of the National Water-Quality Assessment Program
An integrated assessment of the water quality in streams and aquifers in the Wapsipinicon, Iowa, Cedar, and Skunk River basins was conducted in 1996 through 1998 as part of the Eastern Iowa Basins (EIWA) study unit of the U.S. Geological Survey's National Water-Quality Assessment Program (NAWQA). The EIWA study unit is one of 59 study units across the Nation designed to assess the status...
Authors
Stephen Kalkhoff
Major ground-water findings from the National Water-Quality Assessment Program (NAWQA) in Iowa Major ground-water findings from the National Water-Quality Assessment Program (NAWQA) in Iowa
No abstract available.
Authors
Stephen Kalkhoff
Water quality in the eastern Iowa basins, Iowa and Minnesota, 1996-98 Water quality in the eastern Iowa basins, Iowa and Minnesota, 1996-98
The water quality in rivers and streams and in selected aquifers in eastern Iowa and part of southern Minnesota is described and illustrated. Major ions, nitrogen and other nutrients, and pesticides and some of their breakdown compounds were analyzed in both surface and ground water. Biological communities that included fish, invertebrates, and algae, were described in relation to stream...
Authors
Stephen Kalkhoff, Kimberlee K. Barnes, Kent Becher, Mark Savoca, Douglas Schnoebelen, Eric Sadorf, Stephen Porter, Daniel Sullivan
Occurrence of acetochlor and acetochlor metabolites in alluvial aquifers in Iowa Occurrence of acetochlor and acetochlor metabolites in alluvial aquifers in Iowa
No abstract available.
Authors
Stephen Kalkhoff, Mark Savoca, Eric Sadorf, Dana Kolpin, Earl Thurman
Occurrence and distribution of chloroacetanilide and triazine pesticide metabolites in streams in eastern Iowa Occurrence and distribution of chloroacetanilide and triazine pesticide metabolites in streams in eastern Iowa
No abstract available.
Authors
Stephen Kalkhoff, E.M. Thurman