Thursday, February 27, 2014

Research Highlights: Biofuels and Midwestern Water Use

Photo by Irene Miles

On its millions of acres of farmland, Illinois grows enough corn and soybeans to produce more ethanol than any other state in the US. If Illinois farmers decided to grow perennial grasses for biofuel rather than corn and soybeans, though, how might the way Illinois uses water and fertilizer change? That’s what Andy VanLoocke and Carl Bernacchi wanted to know, and they won an IWRC Annual Small Grant to fund their search for an answer. At the end of their project, Andy and Carl told us about their findings, what the research could mean for Illinois water resources, and what Andy is doing with his new PhD.  


What exactly does “cellulosic biofuel feedstock” mean?

A cellulosic biofuel feedstock is a crop that is grown primarily to convert the cellulose, most of a plant’s structural material, into a fuel like ethanol. This is in contrast to the “grain or oil” being used to produce ethanol or biodiesel, because with cellulosic feedstocks the energy source isn’t limited to the seed of the crop, like with corn or soybean. 

Would you please give us a quick overview of the whole project, not just the IWRC-funded piece?
The overall goal of this project was to come up with a quantitative way to assess large-scale land use shifts across the Midwest that are associated with biofuel production. We also looked at the impacts this could have on the critical aspects of our agro-ecosystems, such as the cycling of carbon, water, and nutrients. Within the context of the IWRC funding, we were particularly focused on ecosystem water use, such as determining how producing cellulosic bioenergy crops would alter stream flows and water quality of our rivers. 

Would you talk about the models you used a little bit: what is IBIS, how do you determine model inputs, and how accurate are the results?
Because we are asking questions on such a large scale, and with numerous hypothetical scenarios, we had to use computer models to answer our research questions. To model the production of the crops we chose an ecosystem model called Agro-IBIS, which stands for the Integrated BIoSphere model – Agricultural version. We ran this model in conjunction with a stream flow and nutrient transport model called Terrestrial Hydrology Model with Biogeochemistry (THMB).
To conduct this research, we fed the ecosystem model (Agro-IBIS) climate data including temperature and precipitation. The model then simulated the uptake of carbon through photosynthesis, the loss of water through transpiration and evaporation, and a range of other outputs. We also input management information into Agro-IBIS, such as crop type and fertilization rates that are used with the climate data to determine how much carbon, nitrogen, and water are entering and leaving a given location (typically the size of a county). The results of Agro-IBIS are then given as inputs into THMB, which simulates the movement of water and nitrogen runoff from each location, through the various rivers and streams of the Mississippi River Basin, and eventually out to the Gulf of Mexico. 
We compare the model results to any available observations we can find to insure the model is accurate. For the new cellulosic biofuel crops, information is limited, but we have been able to compare the model predictions for key components of the carbon, water, and nitrogen cycles for a few locations in Central Illinois. So far the models do a pretty good job simulating what we have seen in the field. Given the limited data, there are uncertainties when scaling from the well-measured areas to the whole region. We can increase the confidence in the model over larger spatial scales by modeling existing crops (corn, soy, and wheat), which we have much more information on, and determine how well the modeled data and measured data agree.

What were your major findings? 
The primary question we were trying to address is: What impact would large-scale production of cellulosic feedstock in the Midwest have on water quality and quantity in the Mississippi River Basin? We know from observations that Miscanthus and Switchgrass, the two major leading candidate cellulosic feedstocks and our study focus, use more water than corn and soybean, but require less fertilizer to achieve high yields. When we expanded the study with the computer models we found that, as long as we kept production less than the current fraction levels (i.e. ~40% of corn grain goes to ethanol each year), there was a minimal impact on streamflow for most of the Mississippi River Basin. At the same time we saw that we could significantly improve water quality if we followed these production scenarios. 

Thursday, February 13, 2014

6 Ways to Love your Watershed



This Valentine’s Day, why not spare a thought for your watershed when considering the loved ones in your life? That area of land around you that drains to a common water body, your watershed, does hard work to give you clean and sustaining water. But rather than chocolate and flowers, it would probably prefer you invest in some of these goodies:  

  1. You should probably learn the name of the object of your affection. EPA’s Surf Your Watershed will allow you to do so by searching your zip code, city name, local stream name, or even its Hydrologic Unit Code (HUC). 
  2. Once you’ve found your watershed, you have the opportunity to look at your watershed’s health. Impairments listed for each watershed will tell you what ails your beloved. IWRC’s watershed is afflicted with high phosphorus and nitrogen levels and a very small number of scary things like DDT.
  3. Knowing what hurts your watershed means that you can help heal it. And when it comes to watersheds, the little things really do count, like washing your car at the carwash where the water gets treated. You could also try doing the things you hear about all the time: don’t litter, don’t dump, especially around storm drains, turn off the water when brushing your teeth (or find out your water footprint and cut down on all your water use), use natural lawn care, and safely dispose of unwanted medicines.
  4. Like making anyone feel appreciated, a little quality time can work wonders. Your local non-profits, schools, and municipalities probably sponsor watershed cleanup days. Consider participating. You can find cleanup opportunities all over the nation through organizations like American Rivers, which runs the National River Cleanup, or the Ocean Conservancy, which coordinates the International Coastal Cleanup. More locally, the Alliance for the Great Lakes runs the Adopt-a-Beach program to both clean and monitor the Great Lakes. And if you really want to get crazy, the National Great Rivers Research and Education Center runs a citizen science program to monitor Illinois’s streams called RiverWatch. Trainings teach volunteers how to use macroinvertebrates and water chemistry to determine the health of their local watersheds.
  5. We talk about the things we love. Want to gab about your watershed? Why not join us at Illinois Water 2014, or sign-up for updates from your local watershed groups (helpfully listed on Surf Your Watershed)? Have an idea for what to talk about at Water 2014? Let us know!
  6. But most of all, don’t forget your watershed. Don’t just think about it on Valentine’s Day. What you do upstream will end up in someone else’s downstream, whether that’s his or her back yard, drinking water, food, habitat, national park, or means of making a living. Our actions always draw a reaction. It’s a basic law of physics, and it’s true for water, too.