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geomorphology

GSA abstract: Abundance and Geomorphic Function of Wood in Urban Stream Systems

Later this month, Caytie, Garrett, and I will be representing the Watershed Hydrology Lab at the Geological Society of America Annual Meeting in Seattle, Washington. Garrett will be presenting the following talk on Monday at 2:55 in Conference Center Chelan 5.

Abundance and Geomorphic Function of Wood in Urban Stream Systems

Blauch, G. and Jefferson, A.

Large wood serves important geomorphic and ecologic functions in streams, as established by research set in relatively undisturbed watersheds. However, the dynamics and function of wood in urban streams has not received similar attention. Previous studies have not clearly distinguished between the effects of low recruitment potential due to developed riparian zones and hydrograph flashiness increasing wood mobility. In order to focus on the effects of hydrograph flashiness, our study focuses on wood abundance and function across urban northeastern Ohio streams where protected riparian buffers offer recruitment opportunities. Impervious surface cover is used as a proxy for urbanization’s effect on the stream hydrology. The frequency and geometry of large wood was surveyed within the bankfull channels in 11 stream reaches, with watersheds that span 0.39 – 88 km2 and 0.56 – 40.1% impervious cover. Geometry measurements cover length, diameter, and planform orientation for individual pieces and smaller jams, as well as 3D structure of significant wood jams in 7 of the 11 streams using Structure-from-Motion techniques. Measurements of the long profiles, stream banks, and streambed sediments provide indications of the geomorphic context of large wood with respect to pool formation, bank erosion, and sediment storage. Preliminary results show a decrease in the occurrence of large wood pieces from 36 per 100m of stream length in the least developed watershed to as little as 1 piece per 100m at higher impervious surface covers. Of those streams with wood stored as both individual pieces and as part of jams, 73% of the total wood (by count) is stored as jams on average. In the most developed, urban watersheds, early re-surveys show that even these larger jams can be mobilized. These results suggest that even though wood is available to the stream, flashy urban hydrographs still have an influence on the presence of wood within urban streams. With large wood often considered in management and restoration practices, protection of the riparian buffer is not enough to maintain the presence of wood – and the geomorphic and ecologic benefits provided by it – in these flashy urban systems.

wood jam spanning a stream, man on right side gravel bar looking at something in his hands.

Garrett get ready to take some data on this wood jam in West Creek, August 2017.

GSA abstract: Soils and Geomorphology of Five Reclaimed Surface Mine Sites in the Cuyahoga Valley National Park, Ohio

Later this month, Caytie, Garrett, and I will be representing the Watershed Hydrology Lab at the Geological Society of America Annual Meeting in Seattle, Washington. Caytie will be presenting the following poster on Tuesday, October 24th in spot 257-4 in the Washington State Convention Center.

Soils and Geomorphology of Five Reclaimed Surface Mine Sites in the Cuyahoga Valley National Park, Ohio

Ruhm, C., Jefferson, A., Blackwood, C., Minerovic, A., and Davis, C.

Abandoned mine lands are common to human-altered landscapes. Despite the improvement of remediation techniques, the geomorphic and ecological function of historical abandoned mines persist as a concern to many regions. Cuyahoga Valley National Park (CVNP) is home to ~50 abandoned gravel, sand, and topsoil mines. After mining ceased, these sites were backfilled, compacted, and seeded. Following reclamation, rills and gullies appeared on some steep slopes within the sites. Additionally, reforestation efforts at these sites have not been successful. The causes of these failures are not well understood. Previous studies of coal mines have pointed toward altered chemical properties as a cause of reforestation failure. However, since the CVNP sites lack coal and associated tailings, further research is required to understand how the mining and reclamation affect erosion control and reforestation efforts.
Our research is investigating the geomorphology and soil quality of five of the abandoned mine sites within CVNP relative to four reference sites with similar slope and aspect, but mature forest. We aim to (1) determine the quality of the soils within the sites in comparison to the reference locations, (2) determine if the sites are currently undergoing erosion in exceedance of the reference locations, and (3) inform future reclamation projects to assist in the creation of successful practices.

We have collected ~250 soil samples from the five sites and four reference locations to analyze for grain size distribution, soil pH, concentrations of extractable Al, Ca, Fe, K, Mg, and P, and total C and N. Preliminary results indicate a marked difference in soil pH between the mined (pH 7-8) and forested reference (pH 3.6-6) sites. Measurements of infiltration capacity and bulk density are underway. Preliminary results of bulk density indicate that the density is very high (>2000 kg/m3) in the mined sites, which may be impeding plant growth and promoting overland water flow. Pressure transducers in three gullies on the mined sites indicate water flow during and following intense rainfall, and silt fences are allowing us to quantify sediment flux. Mapping of gully long profiles and cross-sections will enable us to calculate the volume of sediment removed by the gullies since reclamation occurred.

Geological Society of America Abstracts with Programs. Vol. 49, No. 6
doi: 10.1130/abs/2017AM-303598

Grassy hill with trees in the background. Cloudy sky.

One of the sites that Caytie is studying, as it appeared in October 2016. The several acre site was host to invasive Phragmites reeds and a failed tree planting.

Anne’s top papers of 2016 + 3 she co-wrote

Yesterday, I posted an epic analysis of my scientific reading habits in 2016, but I didn’t tell you about the papers I read last year that made my heart sing. And I didn’t take much time to brag about my own contributions to the scientific literature. So I’m going to rectify that omission today.

My top 3 papers of 2016 are (in no particular order):

Of rocks and social justice. (unsigned editorial) Nature Geoscience 9, 797 (2016) doi:10.1038/ngeo2836

The whole thing is absolutely worth reading (and it’s not behind a paywall) but here’s where it really starts to hit home:

Two main challenges stand in the way of achieving a diverse geoscience workforce representative of society: we need to attract more people who have not been wearing checkered shirts, walking boots and rucksacks since secondary school, and we need to retain them.

Waters, C. N., Zalasiewicz, J., Summerhayes, C., Barnosky, A. D., Poirier, C., Ga?uszka, A., … & Jeandel, C. (2016). The Anthropocene is functionally and stratigraphically distinct from the Holocene. Science, 351(6269), aad2622.

Want an up-to-date, data-rich, and condensed summary of why many scientists think it is time for a new geologic epoch? This is the paper to read.

Wu, Q., Zhao, Z., Liu, L., Granger, D. E., Wang, H., Cohen, D. J., … & Zhang, J. (2016). Outburst flood at 1920 BCE supports historicity of China’s Great Flood and the Xia dynasty. Science, 353(6299), 579-582.

I am a sucker for a good mega-paleo-flood story, and this one ticks all of the right boxes. An earthquake generates a landslide, which dams a river, and then fails, resulting in one of the largest floods of the last 10,000 years and alters the course of Chinese history. Geology, archaeology, and history combine in this compelling story.

Plus, a bonus paper, that was definitely one of the best papers I read in 2016.

Shields, C., and C. Tague (2015), Ecohydrology in semiarid urban ecosystems: Modeling the relationship between connected impervious area and ecosystem productivity, Water Resour. Res., 51, 302–319, doi:10.1002/2014WR016108.

I’m cheating a little bit here, because this paper came out in 2015. But I read this paper in 2015, and then I read it twice more in 2016. That’s how much I like it. Why? Because it’s a really nice illustration of how physically-based models can reveal the complex and unexpected ways that ecosystems and watersheds respond to urban environments. In a semi-arid environment, deep rooted vegetation can take advantage of the bonus water that gets delivered from rooftop downspouts that drain out onto the land. The additional water use boosts net primary productivity, potentially enough to offset the loss of productivity that occurred when parts of the landscape were paved and built upon. But while deep rooted vegetation, native to the semi-arid landscape, can take advantage of the bonus water, grass can’t. It’s a cool story, with implications for the way we develop and manage urban landscapes – and the way we model them. (This paper is open access as of January 1, 2017!)

I was thrilled to be able to contribute to 3 papers in 2016. 

Turner, V.K., Jarden, K.M., and Jefferson, A.J., 2016. Resident perspectives on green infrastructure in an experimental suburban stormwater management programCities and the Environment, 9(1): art. 4.

In 2015, my team published a paper showing how the installation of bioretention cells, rain gardens, and rain barrels on a residential street in the Cleveland area substantially decreased stormwater runoff. This paper represents the other side of the story – the side that is, just as important (if not more so) – how the people on the street responded to the addition of this green infrastructure. In short, getting residents on board with stormwater management is a big challenge that we’re going to face as we scale-up from demonstration projects to widespread deployment of these technologies. (This paper is open access and free to all.)

Bell, C.D., McMillan, S.K., Clinton, S.M., and Jefferson, A.J., 2016. Hydrologic response to stormwater control measures in urban watershedsJournal of Hydrology. Online ahead of print. doi: 10.1016/j.jhydrol.2016.08.049.

Bell, C.D., McMillan, S.K., Clinton, S.M., and Jefferson, A.J., 2016. Characterizing the Effects of Stormwater Mitigation on Nutrient Export and Stream ConcentrationsEnvironmental Management. doi:10.1007/s00267-016-0801-4

I’m thrilled that first author Colin Bell completed his doctorate in 2016 and got two papers out to boot. These papers are the culmination of 5 years of research in Charlotte, North Carolina. In the Journal of Hydrology, we try to disentangle the effects of stormwater management from the overall signal of urbanization across 16 watersheds. It turns out that for the level of stormwater management we see in the real world, it’s not enough to counter-act the effects of impervious surfaces (pavement and rooftops) as a driver of the hydrologic behavior of urban streams. In Environmental Management, we aim to understand the influence of stormwater ponds and wetlands on water quality in the receiving streams. This turns out to be quite tricky, because the placement of stormwater management structures spatially correlates with changes in land use, but based on differences in concentration between stormwater structure outflow and the stream, we show that it should be possible. This echoes the findings from our 2015 paper using water isotopes to understand stormwater management influences at one of the same sites. Colin will have another paper or two coming out of his modeling work in the next year or so, and we’re still analyzing more data from this project, so keep your eyes out for more work along these lines.

AGU Abstract: Dynamic Hydraulic Conductivity, Streambed Sediment, and Biogeochemistry Following Stream Restoration

The Watershed Hydrology Lab will be represented at the AGU Fall Meeting in December in the session on “Groundwater-Surface Water Interactions: Identifying and Integrating Physical, Biological, and Chemical Processes.”

Dynamic Hydraulic Conductivity, Streambed Sediment, and Biogeochemistry Following Stream Restoration

Anne Jefferson, Stuart Baker, and Lauren Kinsman-Costello, Kent State University, Kent, OH, United States

Stream restoration projects strive to improve water quality and degraded habitat, yet restoration projects often fall short of achieving their goals. Hyporheic exchange facilitates biogeochemical interaction which can contribute to positive water quality and habitat, but there are limited data on how restoration affects hyporheic processes. Hyporheic flowpaths can be altered by the processes and products of stream restoration, as well as the transport of fine sediment through the stream bed post-restoration. In two northeastern Ohio headwater streams, variations in hydraulic conductivity and pore water chemistry were monitored following restoration, as measures of hyporheic functioning. A second-order stream restored in August 2013, had a slight decrease in average hydraulic conductivity but an increase in heterogeneity from pre-restoration to four months post-restoration. Data collected 10 and 15 months post-restoration show continued declines in hydraulic conductivity throughout large constructed riffles. These piezometers also indicate dominance of downwelling throughout the riffles with only isolated upwelling locations. Grain size analysis of freeze cores collected in streambed sediments show differences suggesting fluvial transport and sorting have occurred since construction was completed. Pore water sampled from piezometers within the riffles had Mn2+ concentrations ten times higher than surface water, suggesting redox transformations are occurring along hyporheic flowpaths. A first-order stream reach, immediately downstream of a dam, restored in April 2014 had no significant change in average hydraulic conductivity between 1 and 2 months post-restoration, but many individual piezometers had increases of over 100% in high gradient positions or decreases of over 50% in low gradient positions. Changes in hydraulic conductivities in both restored streams are thought to be an adjustments from disturbance to a new dynamic equilibrium influenced by the morphology and sediment regime established by restoration, suggesting these are important processes to consider in the design of such projects.

One of the study streams, 3 months post-restoration.

One of the study streams, 3 months post-restoration.

After the dam comes down: groundwater-stream interactions and water quality effects of restored and unrestored reaches in northeastern Ohio

The Watershed Hydrology lab will be out in force for the Geological Society of America annual meeting in Vancouver in October. For the last few days, we’ve been sharing the abstracts of the work we are presenting there.

AFTER THE DAM COMES DOWN: GROUNDWATER-STREAM INTERACTIONS AND WATER QUALITY EFFECTS OF RESTORED AND UNRESTORED REACHES IN NORTHEASTERN OHIO

BROWN, Krista Marie, Geology, Kent State University, Kent, OH 44240, kbooth@kent.edu and JEFFERSON, Anne J., Department of Geology, Kent State University, 221 McGilvrey Hall, Kent, OH 44240

Over that past decade, dam removals have become increasingly popular, as many dams near the end of their life expectancy. With an anticipated increase of dam removals in coming years, this study aims to develop an understanding of groundwater-stream interactions and water quality in former reservoirs after dam removal. Low head dams were removed in 2009 on Plum Creek and Kelsey Creek, tributaries to the Cuyahoga River. Kelsey Creek reservoir remains unaltered and consists of a stream channel flowing through riparian-wetland environments, while Plum Creek reservoir underwent channel restoration in 2011. At Kelsey Creek, 20 piezometers and 3 wells were installed within the former reservoir. Since October 2013, hydraulic heads have been recorded semi-weekly for aquifer modeling and water samples have been taken in the wells and stream. Water quality is being evaluated with field-measured parameters and ion chromatography. Plum Creek is being used to understand the water quality effects of channel restoration.
At Kelsey Creek, interaction between the stream and shallow groundwater is evident. The stream tends to contribute shallow groundwater flow toward the western side of the site and north, parallel to the stream. The well closest to the stream shows variability in specific conductance, indicating bidirectional groundwater-stream exchange and all wells show rapid response to precipitation events. Hydraulic conductivity calculated using the Hvorslev method ranged 2.84×10-2to 7.38×10-6 m/s and poorly correlate with the bulk sediments in Kelsey Creek.
Despite the wetland and groundwater-stream exchange in the unrestored Kelsey Creek, there is little change in stream water quality within the former reservoir site, similar to the restored Plum Creek site. This suggests that there is little water quality benefit to be gained from stream restoration at dam removal sites. Left unaltered, Kelsey Creek provides flood control and groundwater recharge in wetland areas.

Changes in hyporheic exchange and subsurface processes following stream restoration

The Watershed Hydrology lab will be out in force for the Geological Society of America annual meeting in Vancouver in October. Over the next few days, we’ll be sharing the abstracts of the work we are presenting there.

CHANGES IN HYPORHEIC EXCHANGE AND SUBSURFACE PROCESSES FOLLOWING STREAM RESTORATION

BAKER, Stuart B., Department of Geology, Kent State University, 221 McGilvrey Hall, 325 S. Lincoln St, Kent, OH 44242, sbaker51@kent.edu and JEFFERSON, Anne J., Department of Geology, Kent State University, 221 McGilvrey Hall, Kent, OH 44240
Stream restoration is a billion dollar industry with major goals of improving water quality and degraded habitat, yet restoration often falls short of significant improvements in toward these objectives. At present, there are limited data and understanding of the physical and biogeochemical responses to restoration that constrain the potential for water quality and ecological improvements. Hyporheic exchange, the flow of water into and out of the streambed, is an important stream process that serves a critical role in naturally functioning streams, allowing for stream water to interact with the substrate in various processes. Hyporheic flowpaths can be altered by the transport of fine sediment through the stream bed and are thus susceptible to changes in sediment regime and hydraulics, as well as the changes wrought by construction of a restoration project. The goal of this research is to determine the effect of restoration on hyporheic exchange and associated biogeochemical processes. Preliminary results from Kelsey Creek, OH, a second-order stream restored in August 2013, show a slight decrease in average hydraulic conductivity but an increase in heterogeneity from pre-restoration (geometric mean 8.47×10-5 m/s, range 2.67×10-5-3.05×10-4) to four months post-restoration (geometric mean 4.40×10-5 m/s, range 1.18×10-6-1.19×10-3) to ten months post-restoration (geometric mean 1.41×10-5 m/s, range 1.11×10-6-6.40×10-4) in piezometer nests through large constructed riffle structures. These piezometers also indicate dominance of downwelling throughout riffle structures with only isolated locations of upwelling. A stream in Holden Arboretum, OH restored in April 2014 had no significant change in average hydraulic conductivity between 1 and 2 months post-restoration, but many individual piezometers had increases of over 100% or decreases of over 50%. The greater variation in hydraulic conductivities in both restored streams may be adjustment from disturbance to a new dynamic equilibrium. Transient storage and hyporheic exchange were also measured with resazurin injections pre-restoration and post-restoration, and nutrient injections of NH4Cl will compare the nitrogen uptake rates of the restored reach to an unrestored reach downstream.

Damnation film screening in Cleveland on Wednesday

If you haven’t seen it yet, and you are at all interested in dams and dam removal (or are even wondering why people would be interested in dam removal), I encourage you to watch the film Damnation. The film highlights some of the environmental issues associated with dams, showcases the growing movement to get them removed, and shows us the results when dams do come out. Plus, it features gorgeous scenery of Pacific Northwest Rivers. So check out the screening in Cleveland this week (info below) or ask Anne how to get access to her copy of the film.

Here’s the trailer:

The award-winning documentary, Damnation, is coming to Cleveland’s Capitol Theater on Wednesday, September 24th at 7 p.m. The movie tells the story of the use of dams around the United States and the impact that dams have on rivers. It was produced by Yvon Chouinard who, among many other conservation accolades, is the founder of Patagonia.

Kdudley Media is hosting the presentation of the movie at the Capitol and they have graciously invited Friends of the Crooked River to be their special guest. FOCR will have an informational display in the lobby before the showing and have a Q&A session after the movie focusing on local dam removal efforts. In addition, Kdudley has decided to donate any funds raised from the showing of the movie to FOCR in support of our conservation efforts. Here is a link to more information about the film: www.damnationfilm.com

Tickets will be available at the door, as well as on line.

The Capitol Theater is located at W. 65th and Detroit in Cleveland’s District, Gordon Square District. This area is also home to several good restaurants ranging from casual to upscale so you may want to come early and make a night of it.

Hope to see you on September 24th

Social Hour at 6 PM

Film at 7 PM

Q&A concerning dams on the Cuyahoga following show

Development of hyporheic exchange and nutrient uptake following stream restoration

Next week, the Watershed Hydrology Lab will be well represented at the CUAHSI 2014 Biennial Colloquium. We’ll be presenting four posters, so here come the abstracts…

Development of hyporheic exchange and nutrient uptake following stream restoration

Stuart Baker and Anne Jefferson

Stream restoration is a multi-million dollar industry in Ohio, with major goals of improving water quality and degraded habitat. Yet restoration often falls short of significant improvements in water quality and biodiversity. It is thus important to improve the theory and practice of stream restoration in order to achieve greater benefits per dollar spent, yet there are limited data and understanding of the physical and biogeochemical responses to restoration that constrain the potential for water quality and ecological improvements. Hyporheic exchange, the flow of water into and out of the streambed, is an important stream process that serves critical roles in naturally functioning streams, allowing for stream water to participate with the substrate in various processes. Hyporheic flowpaths can be altered by the transport of fine sediment through the stream bed and are thus susceptible to changes in sediment regime and hydraulics, as well as the changes wrought by construction of a restoration project. The goal of this research is to determine the effectiveness of restoration in enhancing hyporheic flow and associated biogeochemical processes to improve water quality. Preliminary results from Kelsey Creek, OH, a second-order stream restored in August 2013, show a decrease in average hydraulic conductivity but an increase in heterogeneity from pre-restoration (geometric mean 8.47×10-5 m/s, range 1.18×10-6-1.19×10-3) to post-restoration (geometric mean 4.41×10-5 m/s, range 2.67×10-5-3.05×10-4) in piezometer nests through large constructed riffle structures. These piezometers also indicate dominance of downwelling throughout riffle structures with only isolated locations of upwelling. Transient storage and hyporheic exchange will be measured with resazurin injections for comparison between pre-restoration and post-restoration, and nutrient injections of NH4Cl at time points following the restoration will compare the nitrogen uptake rates of the restored reach to an unrestored reach downstream. Additional sites are planned for study to include restoration projects of different ages to examine the development of hyporheic exchange and biogeochemistry after completion of restoration projects.

After the dam comes out: groundwater-stream interactions and water quality impacts of former reservoir sites

Next week, the Watershed Hydrology Lab will be well represented at the CUAHSI 2014 Biennial Colloquium. We’ll be presenting four posters, so here come the abstracts…


After the dam comes out: groundwater-stream interactions and water quality impacts of former reservoir sites

Krista Brown and Anne Jefferson

Over that past decade, dam removals have become increasingly popular, as many dams near the end of their life expectancy. With an increasing number of anticipated dam removals coming in the near future this study aims to develop an understanding of groundwater-stream interactions and water quality in former reservoir sites after dam removals have occurred. Low head dams (~2 m) were removed in 2009 from Plum Creek in Kent, Portage County, Ohio and on Kelsey Creek in Cuyahoga Falls, Summit County, Ohio. Kelsey Creek reservoir has been unaltered since the dam removal and consists of a stream channel flowing through riparian- wetland environments, while Plum Creek reservoir underwent channel restoration in 2011. At Kelsey Creek, 20 piezometers and 3 wells were installed in the stream and riparian areas. Pressure transducers were also deployed in each well and stream from November 20, 2013 to January 5, 2014. Hydraulic conductivity was calculated using the Hvorslev method. Since October 2013, hydraulic heads have been recorded semi-weekly and water samples have been taken in the wells and stream. Water quality is being evaluated with field-measured pH, temperature, specific conductance, and dissolved oxygen, and ion chromatography of chloride, bromide, nitrate, sulfate and phosphate concentrations. Plum Creek is being used to understand the water quality effects of channel restoration at former reservoir sites.
At Kelsey Creek, hydraulic conductivity ranges five magnitudes, from 10?2 to 10?6 m/s, but wells near the channel, in an off-channel wetland, and on an adjacent hillslope respond similarly during high flow events. However, the well closest to the stream shows substantial variability in specific conductance, indicating bidirectional groundwater-stream exchange. Despite the wetlands and presumed greater groundwater-stream exchange in the unrestored Kelsey Creek, stream water quality is similar to the restored Plum Creek site. This suggests that the water quality measures considered here should not determine whether to restore channels within former reservoir sites. Findings from this research may be applicable when considering options for future dam removal sites.

Bedload transport videos FTW

Today in Fluvial Processes, I’ll be talking about sediment transport. It’s one of those subjects that can easily get bogged down in lots and lots of math, but I prefer to start out with getting students to watch and describe the processes that occur as grains move along the bed before we start in on the physics and math.

Here’s the grainy video I’ve been showing for years, but it’s still a great way to picture bedload transport: http://geofaculty.uwyo.edu/heller/SedMovs/Dietrich.htm. Kind of sorry about the grainy pun.

Here’s a nice close up video of some large bed sediments, from John Gaffney:

And some much smaller sediments moving across a coarse bed:

There are more videos by John Gaffney where those came from: http://www.youtube.com/user/flyer0lines/videos?view=pl

You can also enjoy this nice top down and cool sidelit view of sand and fine gravel: http://serc.carleton.edu/details/files/31376.html

Curious about how it all happens? Watch a quick primer from Dawn Summer at UC Davis:

Dawn has also got a great set of lecture notes available too. Or, consider taking my Fluvial Processes class at some point down the road.