Posted by: Anne Jefferson | July 20, 2012

I’ve moved…and so has this blog

I’m now part of the Department of Geology at Kent State University. As part of my move, I’ve established a new website at http://all-geo.org/jefferson/.

All new updates will occur at http://all-geo.org/jefferson/blog/.

Please update your bookmarks. Thanks!

Ph.D. student Colin Bell will be presenting the following poster at the American Ecological Engineering Society meeting this week in Syracuse, New York.

Using Watershed Modeling to Optimize Management of Urban Stormwater to Control Stream Nitrogen

Colin Bell
Dr. Sara McMillan
Dr. Christina Tague
Dr. Anne Jefferson
Dr. Sandra Clinton

Urban infrastructure expansion causes the alteration of hydrologic and nutrient regimes, elevating nitrogen (N) concentrations in the streams that receive stormwater runoff. The inclusion of stormwater Best Management Practices (BMPs) in urban watersheds has been found to help ameliorate these problems by retaining water and reducing N concentrations through denitrification and uptake. The Regional Hydro-Ecological Simulation System (RHESSys) is currently being used to test the impact of different BMP implementation strategies and fertilizer application regimes to simulate their effects on instream N in an urbanizing, residential watershed in Charlotte, NC. RHESSys is a distributed, process-based model that simulates natural and anthropogenic N and carbon (C) sources, processing and export. Watershed characterization of two watersheds with contrasting land uses (suburban and forested), along with field monitoring of instream and BMP water chemistry is currently being completed. This will allow us to parameterize the influences of existing BMPs on instream N concentrations, and allow RHESSys to scale up their observed functionality. RHESSys will test multiple, spatially-explicit scenarios to identify the combination of N loading and BMP treatment that minimizes aquatic ecosystem degradation so that land developers can urbanize responsibly.

I will be at the CUAHSI 3rd Biennial Colloquium on Hydrologic Science and Engineering on July 16-18, 2012 in Boulder, Colorado. I’ve been asked to speak in a session on the co-evolution of geomorphology and hydrology. This is a cool opportunity for me, as I’ve been thinking about co-evolution in both volcanic landscapes and Piedmont gullies for the past couple of years. I’m going to attempt to stitch those two very different landscapes and timescales together in one conceptual framework in the talk, and I guess we’ll see how it goes.

Timescales of drainage network evolution are driven by coupled changes in landscape properties and hydrologic response
Anne J. Jefferson

In diverse landscapes, channel initiation locations move up or downslope over time in response to changes in land surface properties (vegetation, soils, and topography) which control the partitioning of water between subsurface, overland, and channelized flowpaths. In turn, channelized flow exerts greater erosive power than overland or subsurface flows, and can much more efficiently denude and dissect the landscape, leading to altered flowpaths and land surface properties. These feedbacks can be considered a fundamental aspect of catchment coevolution, with the headward extent of the stream network and landscape dissection as prime indicators of the evolutionary status of a landscape.

Photo by Ralph McGee, used with Permission.

Gullying in a Piedmont forest, downslope from a pasture. Cabin Creek headwaters, Redlair. Photo by Ralph McGee, used with permission.

Drainage network evolution in response to landscape change may occur over multiple timescales, depending on the rapidity of change in the hydrogeomorphic drivers. Climate and lithology may also modify the rates at which drainage networks respond to change in land surface properties. On basaltic landscapes, such as the Oregon Cascades, timescales of a million years or more can be necessary to evolve from an undissected landscape with slow, deep groundwater drainage to a fully-dissected landscape dominated by shallow subsurface stormflow and rapid hydrograph response in streams. This evolution seems to be driven by a slow change in land surface properties and permeability as a result of weathering, soil development, and mantling by low permeability materials, but may also reflect the high erosion resistance of crystalline bedrock. Conversely, rapid or near-instantaneous changes in land surface properties , such as accompanied the beginning of intensive agriculture in the southeastern Piedmont, can propagate into rapid (1-10 year) changes in channel network extent on clay-rich soils. Where agriculture has been abandoned in this region and forests have regrown, downslope retreat and infilling of extensive gully networks is occurring on decadal timescales.

Posted by: Anne Jefferson | April 25, 2012

Alea Tuttle to defend her M.S. on Monday, April 30th

Earth Science M.S. student, Alea Tuttle, will defend her thesis

POST-PROJECT EVALUATIONS OF URBAN STREAM RESTORATION SITES IN THE SOUTHEASTERN PIEDMONT: STREAMBED SEDIMENT DENITRIFICATION AND GEOMORPHIC COMPLEXITY

on Monday, April 30th, 2012 at 9:30 am in the 4th floor conference room of McEniry Hall on the UNC Charlotte campus.

Alea has been primary advised by Dr. Sara McMillan and I have been her co-advisor. I’ve also had the pleasure of having Alea as my teaching assistant in Fluvial Processes and Hydrogeology this year.  Alea will be remaining at UNCC this summer to act as a technician on a newly-funded project focused on floodplains. We know that she will have great success wherever she heads to after grad school.

Posted by: Anne Jefferson | April 25, 2012

AGU 2011 abstract from our NSF stormwater project

I’m not claiming credit for this project, as it was as undergraduate summer research project advised by my collaborator Sara McMillan, but it is one tangible bit of results that have come out of our NSF-funded stormwater project. More good things are coming soon.

The following poster was presented at the AGU 2011 fall meeting.

The influence of stormwater management practices on denitrification rates of receiving streams in an urban watershed

AU: *Cronenberger, M S
AF: Environmental Sciences, Winthrop University, Rock Hill, SC, USA
AU: McMillan, S K
AF: Engineering Technology, University of North Carolina at Charlotte, Charlotte, NC, USA

Increasing urbanization and the subsequent disruption of floodplains has led to the need for implementing stormwater management strategies to mitigate the effects of urbanization, including soil and streambank erosion, increased export of nutrients and contaminants and decreased biotic richness. Excessive stormwater runoff due to the abundance of impervious surfaces associated with an urban landscape has led to the ubiquitous use of best management practices (BMPs) to attenuate runoff events and prevent the destructive delivery of large volumes of water to stream channels. As a result, effluent from BMPs (i.e. wetlands and wet ponds) has the potential to alter the character of the receiving stream channel and thus, key ecosystem processes such as denitrification. The purpose of this study was to determine the extent to which BMPs, in the form of constructed wetlands and wet ponds, influence in-stream denitrification rates in the urban landscape of Charlotte, NC. Four sites, two of each BMP type, were evaluated. Sediment samples were collected upstream and downstream of the BMP outflow from May-July 2011 to determine the effect of wetland discharge on in-stream nitrogen removal via denitrification. Denitrification rates were determined using the acetylene block method; water column nutrient and carbon concentrations and sediment organic matter content were also measured. Generally, wetland sites exhibited higher denitrification rates, nitrate concentrations and sediment organic matter content. Our work and others has demonstrated a significant positive correlation between nitrate concentration and denitrification rates, which is the likely driver of the higher observed rates at the wetland sites. Geomorphology was also found to be a key factor in elevated denitrification rates at sites with riffles and boulder jams. Sediment organic matter was found to be higher downstream of BMP outflows at all four sites, but demonstrated no significant relationship with denitrification rates. We are continuing to investigate these spatial (e.g. BMPs, streams) and temporal (e.g. storm pulse, delayed wetland release) patterns, particularly in the context of factors that influence the specific drivers of denitrification. Understanding these patterns is critical to managing stormwater in urban landscapes as we aim to improve water quality while enhancing ecosystem functions.

Join the exciting Ecology and Biogeochemistry of Watersheds research group at UNC Charlotte in learning about the effects of stormwater management on urban stream ecosystems.  We are looking for one or more student research assistants for full or part-time work. This is a great opportunity for students looking for hands-on research experience and will be a good resume boost for those intending to go to grad school.

The research assistant will be responsible for helping with some or all of the following:

  • Maintaining field equipment including autosamplers, water level loggers, and temperature probes
  • Collecting discharge (streamflow) data and water samples during and following storms and wet weather
  • Assisting with sediment, water and biological sampling in the field and lab
  • Assisting with laboratory tasks, including sample preparation and analysis
  • Maintaining instrument logs and good records of field and laboratory measurements

We are searching for students interested in part-time or full-time work for the summer. There is also the opportunity to begin work immediately and continue into the next academic year on a part-time basis. Your summer schedule should have enough flexibility to allow you to participate in field work as weather conditions dictate. You must provide your own transportation to and from field sites, but you will be reimbursed for gas. Research assistants will be paid $10/hour.  While desirable, previous experience is not required for these positions.

To apply for these positions, please email your (1) resume, (2) list of relevant coursework,  (3) list of past field and research experiences, and (4) availability for full-time or part-time work in the spring, summer and fall to Sara McMillan (smcmillan at uncc dot edu), Anne Jefferson (ajefferson at uncc dot edu), or Sandra Clinton (sclinto1 at uncc dot edu).  Incomplete applications will not be reviewed.  If you have questions about the work, please email us before applying. You can learn more about our group here: http://coefs.uncc.edu/smcmil10/research/.

We will begin considering applications immediately.

Muddy Creek: A restored urban stream and one of our field sites

Posted by: Anne Jefferson | March 20, 2012

Galapagos Conference Website

I’m working on a review paper on evolution of volcanic ocean islands coming out of the Chapman Conference on the Galapagos I participated in last summer. Rather handily, the conference organizers have put together a nice website with all of the talks, posters, and field trip guides. If you are interested in any of the earth science aspects of volcanic ocean islands, ridge-plume interactions, etc., check out the website. Later this year there will also be an AGU monograph arising from the Conference. I’ll post details when it is published.

basalt, water, waves, and mangroves

Lagoon-Ocean tie channel, Isabella Island, Galapagos, July 2011. Photo by A. Jefferson. Click the image to see more Galapagos photos from me on flickr.

Posted by: Anne Jefferson | March 14, 2012

What do you use Twitter for?

  1. Share
    Off to tell 1st year faculty about benefits/perils of social media. Anyone want to share why you use Twitter? @highlyanne with your reply.
  2. And here’s the answers I got.
  3. Share
    @highlyanne networking & following progress/ideas/field trips with global geotweeps :)
  4. Share
    @highlyanne for work, I’ve used twitter to get mineral spectra, access to journal articles, and rapid programming help.
  5. Share
    @highlyanne Quick feedback/answers to simple Q’s; breaking news & info, geo/science links; fun, intelligent humor.
  6. Share
    @highlyanne Single quickest way to broaden your network beyond ‘usual suspects’ — I’d never have met all these amazing tweeps otherwise
  7. Share
    @highlyanne …it’s like the network of people you *don’t* know.
  8. Share
    @highlyanne – Here’s an overview of some pros/cons re: researchers & social media: bit.ly/xlytGh Hope it’s useful!
  9. Share
    @highlyanne I use Twitter because it puts my finger on the pulse of the research community.
  10. Share
    @highlyanne Also, I think someone at #scio12 said, “It’s not ‘Publish or perish’ now; it’s “Be visible or vanish.'”
  11. Share
    @highlyanne when I’m feeling down or uninspired, the endless excitement for science on twitter reminds me why I love it
  12. Share
    @highlyanne one of my profs had the Starbucks logo on his PPT. I pointed at it and said “that logo changed today.” I knew because of Twitter
  13. Share
    @highlyanne textbooks are static. Twitter makes the topics I study dynamic.
  14. Share
    @highlyanne during my undergrad degree, we saw the death of famous amnesiac H.M. and 40th anniversary of the Stanford Prison Experiment.
  15. Share
    @DoctorZen @highlyanne See my time line early yesterday evening. Real time technical help from experts in my field.
  16. I think many of the folks at the session were still in the “being overwhelmed by it all” stage, but several participants asked very good questions. Maybe even some future bloggers and Tweeters in the group. Not a bad way to spend part of an afternoon.
  17. Share
    Thanks for the twitter reasons everyone. I think there were some takers at the workshop. Plus, I finally got to meet @jamesdtabor.
  18. For my take on what I use Twitter for, and why and how I blog, you can read the post I wrote to prepare myself for the session.
Posted by: Anne Jefferson | March 14, 2012

How I use “new media”

Ironically, I write a blog post about it. I’ve been asked to talk to first year faculty about “Communications Strategies: Using the Internet, Email and New Media in Teaching and Scholarship.” My mandate is vague, so I thought I’d focus on how I use “social media” in my professional life. I’m not going to talk about email. Because, honestly, if they aren’t using email effectively by now, I’m not sure how they got a faculty position. And managing the email-beast is way beyond my expertise.

Instead, let’s talk about blogging and Twitter and the like.

Watershed Hydrogeology Blog (here)

I’ve maintained a “lab blog” here since May 2008. It’s purpose has evolved somewhat, but presently I view it fulfilling the following needs:

  • a place to brag about the cool things my students and I are doing;
  • a place for prospective students to get an idea of what I’m interested in and working on;
  • a place for me to post all of my abstracts, papers, etc. so that I can easily find them again when I need to reference them;
  • a place to post links to interesting miscellany (REU announcements, videos, etc.) that I think might be of interest to me, my students, or other hapless folks who read this site.

At one point, I thought I would use this site as a way to aggregate all of my on-line writing. But I haven’t always kept up with that. However, I still do sometimes cross-post between here and my other blog, Highly Allochthonous. I should be better about it actually.

I haven’t asked my students to write on the blog, though I could probably let them know it is available to them if they want to do so. I figure graduate students have enough on their plates without being obligated to write a blog. I would be open to any student who did want to write posts here, though I’d probably want to work out a system for vetting posts so that they wouldn’t contain regrettable or unpublished material.

Highly Allochthonous

I write this blog along with another geologist. Here I am writing for an audience that ranges from professional geoscientists, to K-12 teachers, to the interested public, to whoever Google search delivers. We tend to write things that we are interested in and we think others might be too. Our writing there is less technical than the scientific literature (or the lab blog), but posts there are more in-depth and analytical than here. I also pay more attention to my writing style. 

I’ve written a lot about current events, scientific papers, and particular places on the landscape, and a little bit about issues of diversity in science, the lives of academic scientists, and the way I teach. We also periodically do compilations of things we’ve linked to on Twitter.

My pace of writing at Highly Allochthonous ebbs and flows depending on my workload and inspiration. The last few months have been pretty sparse, but I suspect it will pick up again in the summer and fall. I’ve been blogging there since spring 2008 as well.

Twitter 

I tweet as @highlyanne – mostly about water science and resource issues, geology, geomorphology, climate, and science careers. Basically things that I find interesting when I am reading on-line or off-line. I also usually Twitter a lot more socially than blogs. A lot of my tweets will be replies to friends or colleagues on Twitter. Both my PhD advisor and undergraduate advisor are on Twitter actually, though one is more active than the other.

What I get out of all of it

  • A collegial atmosphere with more diverse scientists and interested citizens than I see in real life
  • Knowledge of a wider breadth of current events in science than I would get from reading journals
  • Practice writing for a variety of audiences (blogging has undoubtedly made me a better writer)
  • Spill-over knowledge into my teaching
  • More visibility than your average assistant professor (media interviews, book reviews, attention from my scientific societies)
  • Quick answers to questions either scientific or pedagogical (“crowd-sourcing”)

 

Posted by: Anne Jefferson | March 7, 2012

Spring Break: tracer injection in Beaver Dam Creek

Spring Break: tracer injection in Beaver Dam Creek

Some of our students are in the field this week, injecting Cl- and Br- into a restored reach and an unrestored reach in tributaries of Beaver Dam Creek. Our goal is to understand the role of wood jams versus restoration structures in promoting stream-hyporheic exchange.

In the photo are Alea, Xueying, and Mackenzie. Photo by Brittany. They’ve got it so capably handled they didn’t even need Sandra or I out there with them today, but I’m going tomorrow for an excuse to be in the field as much as anything.

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