The 2012 GA Harris Research Instrumentation Fellowship winners are:
Kristina Hopkins, University of Pittsburgh
Evaluation of Green Stormwater Infrastructure Impacts on Urban Hydrology
Clarification of urban hydrologic budgets is needed to improve water management in complicated urban systems. The aim of this research is to clarify changes in water inputs and outputs in an urbanized catchment and evaluate green infrastructure effectiveness in rerouting water to slower, subsurface flow paths. Green infrastructure uses vegetation and soil amendments to reduce stormwater runoff at the source and promote infiltration and water storage. Soil moisture sensors and water depth loggers, will be installed in two rain gardens and a control site at the Phipps Conservancy, located in Pittsburgh, PA. Sensors will continuously monitor soil moisture, water depth, temperature and conductivity at each site. Data collected will be used to characterize soil water dynamics and rain garden water storage. Results from this study will clarify the benefits of green infrastructure as a stormwater management practice.
Alison Doniger, Oregon State University
Establishing Irrigation Criteria for Corn Lily
In recent years, corn lily (Veratrum californicum) has garnered increased interest from the medical community because of its cancer fighting properties. Preliminary trials of the corn lily based drug IPI-926 (Infinity Pharmaceutical) on human subjects have yielded very promising results in the treatment of both basal cell carcinoma and pancreatic cancer. Establishing cultivation criteria for corn lily will be crucial in order to guarantee a steady supply of IPI-926. The Oregon State University Malheur Experiment Station (MES) has conducted drip irrigation trials on corn lily for the past two growing seasons with the aim of characterizing the range of soil water tension that produces maximum corn lily growth. Decagon instrumentation will be used to measure soil water tension and soil moisture content in each of five treatments in the irrigation trial plots.
Elise Wygant, University of Georgia
Investigating the lack of trade-off betwen drought resistance and maximum productivity
Changes in global precipitation patterns are predicted to affect plant productivity in both natural and agricultural systems throughout the world. One of the major concerns of these precipitation changes is that some species will face increased water limitations causing decreases in plant productivity. It has been demonstrated that species which are more drought resistant tend to have a low maximum productivity when grown under well watered conditions. However preliminary evidence suggests that Helianthus porteri, a species which is found on the hot, dry granite outcrops of the Southeastern US, does not exhibit this tradeoff. Comparing drought resistant responses of H. porteri to its two closest relatives, H. agrestis and H. carnosus, which inhabit moist soils, can provide useful information for future agricultural. My assessment of these species, especially H. porteri, will expand efforts to mine wild Helianthus species for drought resistance traits for agricultural purposes. My goal is to provide insight into which traits may be useful for enhancing agricultural productivity in areas where water limitation is expected to become problematic in the future.
Kate Cassity, University of Georgia
Calibrating Leaf Wetness Sensors to Measure Dew Quantity in a Study of Ammonia Volatization from Suface-Applied Broiler Litter
Large quantities of broiler litter are produced annually from commercial chicken production. It commonly used as fertilizer and is a good source for plant available nitrogen in pastures and crops. The amount of plant available nitrogen and nitrogen loss to the atmosphere through ammonia volatilization is dependent soil characteristics, application rates, and environmental factors. Understanding the importance of rain, relative humidity, temperature, soil moisture, and dew deposition on volatilization and other nitrogen transformations in litter will lead to a better understanding of nitrogen applied to pasture and modeling for more precise application rates.
Cornelius Adewale, Washington State University
Monitoring N Leaching Under Organic Farm Management
Nitrogen is the most vital nutrient used in agricultural systems and contributes greatly to the economic viability, sustainability, and improvement of cropping systems throughout the world. Its management however has been linked to myriad of global problems ranging from groundwater pollution as a result of N leaching beyond root zones, eutrophication as result of its losses in surface runoff/erosion and its huge contribution to global climate change in the form of N20 emission. Optimizing N management in organic systems is a challenge because of high N sensitivity and the unpredictability of N mineralization from organic fertilizers and soil organic matter. Also application of compost and organic fertilizers to increase soil fertility which is prevalent in organic systems may increase the potential for unintended groundwater contamination by nitrate leaching. There is thus a need for evaluation of the impact of organic farming practices on soil organic matter, Greenhouse gases emissions, and nutrient fate. Using the Decagon Drain Gauge G3, I will be monitoring the flux of water and nitrogen draining from the vadose zone to help determine the nutrient availability and effects of common inputs, crops and practices used on N leaching in 5 organic focus farms located in various parts of Washington State. Data from this research will help us to parameterize and evaluative predictive models for improvement of organic fertilizer management.
Tim Aston, University of Wyoming
Improving Crop Growth Under Drought: an approach using genetics and the precise measurement and control of soil moisture
There is potential and impetus to develop crops either through breeding or genetic engineering that have traits that allow for greater growth under conditions of drought. While moving through a plant, much of the resistance that water experiences is from passing through membranes in the leaves and roots. Plants are able to decrease their overall resistance to water flow by creating proteins, called aquaporins, that insert themselves into these membranes and act as water channels. Crop genotypes that have a greater capacity to utilise these proteins to decrease their overall resistance to water flow, may be able to assimilate carbon for a greater amount of time each day before their water potentials reach the point where their stomata need to close. Genotypes of an important crop, rapeseed oil (Brassica rapa), have been identified with varying levels of aquaporin function. These genotypes will be grown under carefully controlled combinations of soil and atmospheric drought in a custom made automated system utilising Decagon soil moisture probes, to determine if this trait allows droughted crops to fix greater amounts of carbon and hence grow faster.
Iain Hawthorne, University of British Columbia
Biochar Impacts on Soil Water Dynamics and Leaching in a Douglas-Fir Forest Soil
Biochar is a very stable form of organic carbon (C) produced by pyrolysis of biomass. Its use in agricultural soils has been suggested as a means for reducing nutrient leaching losses and greenhouse gas emissions while increasing crop yields and soil carbon storage. I seek to evaluate the potential use of biochar derived from Douglas-fir and applied to Douglas-fir forest soils to improve soil water dynamics and soil C storage. Decagon MPS-2 and GS3 sensors will be installed at a well established research site to measure soil water characteristics for four treatments: (i) 5 t ha-1 biochar, (ii) 200 Kg N ha-1 of Urea fertilizer, (iii) biochar plus fertilizer each at aforementioned application rates, and (iv) control. Soil cores taken from biochar treated field soils will be brought to the Decagon laboratories (Pullman, WA) where soil water characteristics curves will be determined using the Decagon Hyprop and WPC4. By focusing on Douglas-fir we are representing the forest type with the largest latitudinal range of any commercial coniferous forest in North America. Results of this study are anticipated to help in directing forest harvesting away from dwindling areas of old-growth forest by evaluating strategies for improving the sustainability of Douglas-fir production within existing managed forest areas.
Thair B. Patros, University of Guelph
Analysing and Improving the Water Table Fluctuation Method of Estimating Groundwater Recharge
Groundwater recharge (GWR) measurements in urban and rural areas are crucial for many applications, including understanding the spatial and temporal dynamics of groundwater availability and developing source water protection guidelines. Substantial gaps exist in our knowledge of GWR and accurate estimates are elemental for the characterization of the hydrological budget. A novel technique is under development so that recharge (R) can be quantified accurately at the local scale on a 5 min basis (averaged hourly) year-round using the water table fluctuation (WTF) method in combination with the soil water budget monitoring. The ability to measure R frequently over the entire year for multi-years is critical as often substantial R occurs over a short time period of robust dynamic. The expected outcomes and the significance of the project are; (1) obtaining GWR measurements at the local scale on a year-round basis, which are currently scarce or even completely lacking for many regions of Ontario and thus would provide a valuable database for guiding development or any policy requiring GWR, (2) using this database to calibrate and test estimates of the spatial and temporal variability in regional-scale (watershed scale) GWR from approximate statistical techniques or deterministic means using precipitation and soil texture, for example, and, (3) providing guidance on how to supplement equipment at pre-existing weather stations to measure GWR at the station. Guidance might include how many water-table wells, piezometers, soil water content and temperature sensors, tensiometers, and Drain Gauges need to be installed to estimate GWR within a desired confidence interval.