Jonathan M Friedman, PhD
Jonathan Friedman is a Hydrologist at the Fort Collins Science Center.
Since joining the Fort Collins Science Center in 1993, Jonathan has devoted his career to studying interactions among riparian vegetation, river flow and channel change. Present research topics include use of riparian tree rings to reconstruct past river flow, and determination of the effect of riparian vegetation on bank stability.
Professional Experience
1993–present, Research Hydrologist, USGS Fort Collins Science Center, Fort Collins, CO
1990–1993, Hydrologist, USGS Water Resources Division, Lakewood, CO
1988–1990, Community College Instructor, Bellevue Community College, Olympic College and Front Range Community College, Washington and Colorado.
1988 Assistant Natural Area Scientist, Washington Natural Heritage Program, Olympia, Washington
Education and Certifications
Ph.D. Environmental, Population and Organismic Biology, University of Colorado, Boulder, 1993
M.S. Oceanography and Limnology, University of Wisconsin, Madison, 1987
B.S. Biology, Massachusetts Institute of Technology, 1983
Affiliations and Memberships*
Ecological Society of America
American Geophysical Union
Science and Products
Filter Total Items: 92
Dating floodplain sediments using tree-ring response to burial
Floodplain sediments can be dated precisely based on the change in anatomy of tree rings upon burial. When a stem of tamarisk (Tamarix ramosissima) or sandbar willow (Salix exigua) is buried, subsequent annual rings in the buried section resemble the rings of roots: rings become narrower, vessels within the rings become larger, and transitions between rings become less distinct. We combined observ
Authors
J. M. Friedman, K.R. Vincent, P.B. Shafroth
Dominance of non-native riparian trees in western USA
Concern about spread of non-native riparian trees in the western USA has led to Congressional proposals to accelerate control efforts. Debate over these proposals is frustrated by limited knowledge of non-native species distribution and abundance. We measured abundance of 44 riparian woody plants at 475 randomly selected stream gaging stations in 17 western states. Our sample indicates that Tamari
Authors
J. M. Friedman, G.T. Auble, P.B. Shafroth, M.L. Scott, M.F. Merigliano, M.D. Freehling, E.R. Griffin
Use of individualistic streamflow-vegetation relations along the Fremont River, Utah, USA to assess impacts of flow alteration on wetland and riparian area
We analyzed the transverse pattern of vegetation along a reach of the Fremont River in Capitol Reef National Park, Utah, USA using models that support both delineation of wetland extent and projection of the changes in wetland area resulting from upstream hydrologic alteration. We linked stage-discharge relations developed by a hydraulic model to a flow-duration curve derived from the flow history
Authors
G.T. Auble, M.L. Scott, J. M. Friedman
Delayed effects of flood control on a flood-dependent riparian forest
The downstream effects of dams on riparian forests are strongly mediated by the character and magnitude of adjustment of the fluvial–geomorphic system. To examine the effects of flow regulation on sand-bed streams in eastern Colorado, we studied the riparian forest on three river segments, the dam-regulated South Fork Republican River downstream of Bonny Dam, the unregulated South Fork Republican
Authors
Gabrielle L. Katz, Jonathan M. Friedman, Susan W. Beatty
Vegetation responses to dam removal
No abstract available.
Authors
Patrick B. Shafroth, Jonathan M. Friedman, Gregor T. Auble, Michael L. Scott
Potential responses of riparian vegetation to dam removal
Throughout the world, riparian habitats have been dramatically modified from their natural condition. Dams are one of the principal causes of these changes, because of their alteration of water and sediment regimes (Nilsson and Berggren 2000). Because of the array of ecological goods and services provided by natural riparian ecosystems (Naiman and Decamps 1997), their conservation and restoration
Authors
P.B. Shafroth, J. M. Friedman, G.T. Auble, M.L. Scott, J.H. Braatne
Extreme floods, channel change, and riparian forests along ephemeral streams
The geomorphic effectiveness of extreme floods increases with aridity and decreasing watershed size. Therefore, in small dry watersheds extreme floods should control the age structure and spatial distribution of populations of disturbance-dependent riparian trees. We examined the influence of extreme floods on the bottomland morphology and forest of ephemeral streams in a semiarid region. Along si
Authors
J. M. Friedman, V.J. Lee
Effects of physical disturbance and granivory on establishment of native and alien riparian trees in Colorado, USA
In western North America, the alien Elaeagnus angustifolia L. invades riparian habitats usually dominated by pioneer woody species such as Populus deltoides Marshall ssp. monilifera (Aiton) Eckenwalder. We conducted manipulative field experiments to compare the importance of physical disturbance and granivory for seedling establishment of these two species. We planted seeds of both species in dist
Authors
G.L. Katz, J. M. Friedman, S.W. Beatty
Classification of river regimes: A context for hydroecology
Over the past 30 years, ecologists have demostrated the importance of flow and temperature as primary variables in driving running water, riparian and floodplain ecosystems. As it is important to assess the size and timing of discharge variations in relation to those in temperature, a method is proposed that uses multivariate techniques to separately classify annual discharge and temperature regim
Authors
W. R. Osterkamp, J. M. Friedman
Floods, flood control, and bottomland vegetation
Bottomland plant communities are typically dominated by the effects of floods. Floods create the surfaces on which plants become established, transport seeds and nutrients, and remove establish plants. Floods provide a moisture subsidy that allows development of bottomland forests in arid regions and produce anoxic soils, which can control bottomland plant distribution in humid regions. Repeated f
Authors
Jonathan M. Friedman, Gregor T. Auble
High flow and riparian vegetation along the San Miguel River, Colorado
Riparian ecosystems are characterized by abundance of water and frequent flow related disturbance. River regulation typically decreases peak flows, reducing the amount of disturbance and altering the vegetation. The San Miguel River is one of the last relatively unregulated rivers remaining in the Colorado River Watershed. One goal of major landowners along the San Miguel including the Bureau of L
Authors
J. M. Friedman, G.T. Auble
The disparity between extreme rainfall events and rare floods - with emphasis on the semi-arid American West
Research beginning 40 years ago suggested that semi-arid lands of the USA have higher unit discharges for a given recurrence interval than occur in other areas. Convincing documentation and arguments for this suspicion, however, were not presented. Thus, records of measured rainfall intensities for specified durations and recurrence intervals, and theoretical depths of probable maximum precipitati
Authors
W. R. Osterkamp, J. M. Friedman
Science and Products
Filter Total Items: 92
Dating floodplain sediments using tree-ring response to burial
Floodplain sediments can be dated precisely based on the change in anatomy of tree rings upon burial. When a stem of tamarisk (Tamarix ramosissima) or sandbar willow (Salix exigua) is buried, subsequent annual rings in the buried section resemble the rings of roots: rings become narrower, vessels within the rings become larger, and transitions between rings become less distinct. We combined observ
Authors
J. M. Friedman, K.R. Vincent, P.B. Shafroth
Dominance of non-native riparian trees in western USA
Concern about spread of non-native riparian trees in the western USA has led to Congressional proposals to accelerate control efforts. Debate over these proposals is frustrated by limited knowledge of non-native species distribution and abundance. We measured abundance of 44 riparian woody plants at 475 randomly selected stream gaging stations in 17 western states. Our sample indicates that Tamari
Authors
J. M. Friedman, G.T. Auble, P.B. Shafroth, M.L. Scott, M.F. Merigliano, M.D. Freehling, E.R. Griffin
Use of individualistic streamflow-vegetation relations along the Fremont River, Utah, USA to assess impacts of flow alteration on wetland and riparian area
We analyzed the transverse pattern of vegetation along a reach of the Fremont River in Capitol Reef National Park, Utah, USA using models that support both delineation of wetland extent and projection of the changes in wetland area resulting from upstream hydrologic alteration. We linked stage-discharge relations developed by a hydraulic model to a flow-duration curve derived from the flow history
Authors
G.T. Auble, M.L. Scott, J. M. Friedman
Delayed effects of flood control on a flood-dependent riparian forest
The downstream effects of dams on riparian forests are strongly mediated by the character and magnitude of adjustment of the fluvial–geomorphic system. To examine the effects of flow regulation on sand-bed streams in eastern Colorado, we studied the riparian forest on three river segments, the dam-regulated South Fork Republican River downstream of Bonny Dam, the unregulated South Fork Republican
Authors
Gabrielle L. Katz, Jonathan M. Friedman, Susan W. Beatty
Vegetation responses to dam removal
No abstract available.
Authors
Patrick B. Shafroth, Jonathan M. Friedman, Gregor T. Auble, Michael L. Scott
Potential responses of riparian vegetation to dam removal
Throughout the world, riparian habitats have been dramatically modified from their natural condition. Dams are one of the principal causes of these changes, because of their alteration of water and sediment regimes (Nilsson and Berggren 2000). Because of the array of ecological goods and services provided by natural riparian ecosystems (Naiman and Decamps 1997), their conservation and restoration
Authors
P.B. Shafroth, J. M. Friedman, G.T. Auble, M.L. Scott, J.H. Braatne
Extreme floods, channel change, and riparian forests along ephemeral streams
The geomorphic effectiveness of extreme floods increases with aridity and decreasing watershed size. Therefore, in small dry watersheds extreme floods should control the age structure and spatial distribution of populations of disturbance-dependent riparian trees. We examined the influence of extreme floods on the bottomland morphology and forest of ephemeral streams in a semiarid region. Along si
Authors
J. M. Friedman, V.J. Lee
Effects of physical disturbance and granivory on establishment of native and alien riparian trees in Colorado, USA
In western North America, the alien Elaeagnus angustifolia L. invades riparian habitats usually dominated by pioneer woody species such as Populus deltoides Marshall ssp. monilifera (Aiton) Eckenwalder. We conducted manipulative field experiments to compare the importance of physical disturbance and granivory for seedling establishment of these two species. We planted seeds of both species in dist
Authors
G.L. Katz, J. M. Friedman, S.W. Beatty
Classification of river regimes: A context for hydroecology
Over the past 30 years, ecologists have demostrated the importance of flow and temperature as primary variables in driving running water, riparian and floodplain ecosystems. As it is important to assess the size and timing of discharge variations in relation to those in temperature, a method is proposed that uses multivariate techniques to separately classify annual discharge and temperature regim
Authors
W. R. Osterkamp, J. M. Friedman
Floods, flood control, and bottomland vegetation
Bottomland plant communities are typically dominated by the effects of floods. Floods create the surfaces on which plants become established, transport seeds and nutrients, and remove establish plants. Floods provide a moisture subsidy that allows development of bottomland forests in arid regions and produce anoxic soils, which can control bottomland plant distribution in humid regions. Repeated f
Authors
Jonathan M. Friedman, Gregor T. Auble
High flow and riparian vegetation along the San Miguel River, Colorado
Riparian ecosystems are characterized by abundance of water and frequent flow related disturbance. River regulation typically decreases peak flows, reducing the amount of disturbance and altering the vegetation. The San Miguel River is one of the last relatively unregulated rivers remaining in the Colorado River Watershed. One goal of major landowners along the San Miguel including the Bureau of L
Authors
J. M. Friedman, G.T. Auble
The disparity between extreme rainfall events and rare floods - with emphasis on the semi-arid American West
Research beginning 40 years ago suggested that semi-arid lands of the USA have higher unit discharges for a given recurrence interval than occur in other areas. Convincing documentation and arguments for this suspicion, however, were not presented. Thus, records of measured rainfall intensities for specified durations and recurrence intervals, and theoretical depths of probable maximum precipitati
Authors
W. R. Osterkamp, J. M. Friedman
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government