Jonathan 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, quantification of federal reserved water rights, 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
Genetic and environmental influences on leaf phenology and cold hardiness of native and introduced riparian trees
Progression of stream bank erosion dudring a large flood, Rio Puerco, New Mexico
Erosional consequence of saltcedar control
Influence of flow variability on floodplain formation and destruction, Little Missouri River, North Dakota
Latitudinal variation in cold hardiness in introduced Tamarix and native Populus
Transverse and longitudinal variation in woody riparian vegetation along a montane river
Use of individualistic streamflow-vegetation relations along the Fremont River, Utah, USA to assess impacts of flow alteration on wetland and riparian area
Delayed effects of flood control on a flood-dependent riparian forest
Dating floodplain sediments using tree-ring response to burial
Modeling effects of bank friction and woody bank vegetation on channel flow and boundary shear stress in the Rio Puerco, New Mexico
Dominance of non-native riparian trees in western USA
Dating floodplain sediments using tree-ring response to burial
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
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Filter Total Items: 88
Genetic and environmental influences on leaf phenology and cold hardiness of native and introduced riparian trees
To explore the roles of plasticity and genetic variation in the response to spatial and temporal climate variation, we established a common garden consisting of paired collections of native and introduced riparian trees sampled along a latitudinal gradient. The garden in Fort Collins, Colorado (latitude 40.6°N), included 681 native plains cottonwood (Populus deltoides subsp. monilifera) and introdAuthorsJ. M. Friedman, J. E. Roelle, B.S. CadeProgression of stream bank erosion dudring a large flood, Rio Puerco, New Mexico
In August 2006, a large flood following saltcedar control efforts through a 12-km long segment of the Rio Puerco arroyo resulted in extensive lateral erosion of the streambanks. Almost all woody vegetation on the floodplain and channel banks had been killed by aerial spraying with herbicide in September 2003. During the flood, dead woody bank stems were either removed by the >4-m-deep flood flow oAuthorsEleanor R. Griffin, J. Dungan Smith, Jonathan M. Friedman, Kirk R. VincentErosional consequence of saltcedar control
Removal of nonnative riparian trees is accelerating to conserve water and improve habitat for native species. Widespread control of dominant species, however, can lead to unintended erosion. Helicopter herbicide application in 2003 along a 12-km reach of the Rio Puerco, New Mexico, eliminated the target invasive species saltcedar (Tamarix spp.), which dominated the floodplain, as well as the nativAuthorsK.R. Vincent, J. M. Friedman, E.R. GriffinInfluence of flow variability on floodplain formation and destruction, Little Missouri River, North Dakota
Resolving observations of channel change into separate planimetric measurements of floodplain formation and destruction reveals distinct relations between these processes and the flow regime. We analyzed a time sequence of eight bottomland images from 1939 to 2003 along the Little Missouri River, North Dakota, to relate geomorphic floodplain change to flow along this largely unregulated river. AtAuthorsJ.R. Miller, J. M. FriedmanLatitudinal variation in cold hardiness in introduced Tamarix and native Populus
To investigate the evolution of clinal variation in an invasive plant, we compared cold hardiness in the introduced saltcedar (Tamarix ramosissima, Tamarix chinensis, and hybrids) and the native plains cottonwood (Populus deltoidessubsp. monilifera). In a shadehouse in Colorado (41°N), we grew plants collected along a latitudinal gradient in the central United States (29–48°N). On 17 occasions betAuthorsJonathan M. Friedman, James E. Roelle, John F. Gaskin, Alan E. Pepper, James R. ManhartTransverse and longitudinal variation in woody riparian vegetation along a montane river
This study explores how the relationship between flow and riparian vegetation varies along a montane river. We mapped occurrence of woody riparian plant communities along 58 km of the San Miguel River in southwestern Colorado. We determined the recurrence interval of inundation for each plant community by combining step-backwater hydraulic modeling at 4 representative reaches with Log-Pearson analAuthorsJ. M. Friedman, G.T. Auble, E.D. Andrews, G. Kittel, R.F. Madole, E.R. Griffin, Tyler M. AllredUse 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 historyAuthorsG.T. Auble, M.L. Scott, J. M. FriedmanDelayed 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 RepublicanAuthorsGabrielle L. Katz, Jonathan M. Friedman, Susan W. BeattyDating 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 observAuthorsJ. M. Friedman, K.R. Vincent, P.B. ShafrothModeling effects of bank friction and woody bank vegetation on channel flow and boundary shear stress in the Rio Puerco, New Mexico
[1] We have applied a physically based model for steady, horizontally uniform flow to calculate reach-averaged velocity and boundary shear-stress distributions in a natural stream with woody vegetation on the channel banks. The model calculates explicitly the form drag on woody plant stems and includes the effects of vegetation on the boundary shear stress, velocity, and turbulence fields. AverageAuthorsE.R. Griffin, J. W. Kean, K.R. Vincent, J.D. Smith, J. M. FriedmanDominance 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 TamariAuthorsJ. M. Friedman, G.T. Auble, P.B. Shafroth, M.L. Scott, M.F. Merigliano, M.D. Freehling, E.R. GriffinDating 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 observAuthorsJ. M. Friedman, K.R. Vincent, P.B. ShafrothNon-USGS Publications**
Friedman, J.M., M.L. Scott, and W.M. Lewis, Jr. 1995. Restoration of riparian forest using irrigation, artificial disturbance, and natural seedfall. Environmental Management. 19(4): 547-5.Auble, G.T., J.M. Friedman, and M.L. Scott. 1996. Test of a hydroperiod relation to predict changes in riparian vegetation. From big rivers to small streams. Kansas City, Missouri: Society of Wetland Scientists. p. 25-26.Friedman, J.M., G.T. Auble, and M.L. Scott. 1995. Geomorphic requirements for establishment and maintenance of cottonwood forest. Proceedings of the 46th annual meeting of the Great Plains Agricultural Council Forestry Committee. Great Plains Agricultural Council Publication No. 149. Manhattan, KS: Great Plains Agricultural Council. p. 80-88.
Friedman, J.M., M.L. Scott, G.T. Auble, and L.S. Ischinger. 1995. Plains cottonwood regenerates from natural seedfall on disturbed, irrigated sites. NBS Information Bulletin. Washington, DC: National Biological Service. 3 p.Auble, G.T., J.M. Friedman, and M.L. Scott. 1995. Regeneration processes and conservation of riparian forests in the Great Plains. Proceedings of the biodiversity conservation strategies for the Great Plains symposium. Austin, TX: The Nature Conservancy. p. 36-37.Auble, G.T., J.M. Friedman, M.L. Scott, and L.S. Ischinger. 1994. Geomorphic processes determine instream flow effects on cottonwood regeneration. NBS Information Bulletin 83. Washington, DC: U.S. Geological Survey. 1-3 p.Auble, G.T., M.L. Scott, J.M. Friedman, and L.S. Ischinger. 1994. Modeling effects of flow alteration on riparian vegetation. Research Information Bulletin 65. Washington, DC: National Biological Survey. 3 p.Shafroth, P.B., J.M. Friedman, and L.S. Ischinger. 1994. River salinity has little influence on establishment of cottonwood and saltcedar. Research Information Bulletin 94-95. NBS Information Bulletin.**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
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*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