Location: Soil, Water & Air Resources Research2013 Annual Report
1a. Objectives (from AD-416):
Project objectives are: 1) Measure and model the impact of agricultural systems (animal and cropping) on air quality components to identify and develop potential mitigation strategies, 2) Measure and model the impact of agricultural systems on greenhouse gas emissions and develop and evaluate potential mitigation strategies, and 3) Measure and model soil and atmospheric factors limiting water, nitrogen, and light use efficiency of annual and perennial cropping systems to determine how they can become more resilient to climate change.
1b. Approach (from AD-416):
Studies across the soil-plant-atmosphere continuum in this project will develop new methods for quantifying emission and dispersion (particulates, NH3, VOC’s) from animal and cropping systems, improve methods for measuring different compounds in the air to provide increased quantitative capability to measure impacts of CAFO’s on air quality, determine greenhouse gas emissions (N2O, CH4, CO2) from cropping systems, and quantify effects of changing climate on water, light, and nitrogen use by crops. The initial development of a lidar-based approach to measure plume dynamics from animal facilities will be evaluated to produce a remote-sensing approach that will be used to guide sampling methods that use point-based samplers. These data will be collected over a range of facilities and throughout the day to capture the range of atmospheric stability conditions. Air sampling methods for volatile organic compounds will be accomplished with a range of methods from sorbent tubes and canisters. These will also be coupled with methods to measure the volatile organic compounds attached to particulates. These observations will be collected in different livestock facilities. Greenhouse gas emissions will be quantified using soil chambers for a range of soil management and nitrogen management studies to quantify the emissions throughout a year. Measures of water, nitrogen, carbon accumulation, and light use efficiency will use an integrated approach that blends micrometeorological with physiological measurements. These experiments will be conducted using field-scale environments and will integrate all efficiency factors into a combined assessment. The energy balance approach used in these studies blends the fast response of CO2 and H2O vapor signals with sonic anemometers, net radiation components, soil heat flux, and surface temperature along with remote sensing to obtain growth characteristics of the crop. Studies will be conducted in the rhizotron to assess the impact of rapidly induced temperature changes on crop physiological responses under a range of soil water conditions. Accomplishing these three objectives will result in the development of agricultural practices and mitigation strategies that reduce environmental impact, while maintaining or increasing productivity. Mitigation strategies to reduce GHG emissions will balance agricultural production efficiency and increased carbon capture and nitrogen use efficiency. Climate change and its impact on cropping systems raise additional concerns regarding resilience of current production practices and plant adaption to those changes. Methods are needed to quantify plant-climate interaction to link field observations with simulation models for corn, soybean, wheat, and native prairie systems. Developing a long-term program to quantify plant response to climate anomalies will also establish a database for developing more resilient crop production systems. This research will enhance scientific knowledge and provide information for producers and policymakers to maintain the viability of agricultural systems.
3. Progress Report:
Objective 1. Quantifying accurate particulate and gas emissions to the atmosphere is essential to addressing air quality issues from livestock production facilities. Particulate emissions from animal production buildings do not possess Gaussian characteristics which form the basis of current emission model predictions. New retrieval algorithms for lidar scanned data were developed and are being tested against previous year’s data. Advanced analysis of high frequency turbulence data are being employed to develop turbulence intensity ratings. A study in Delaware combined lidar, turbulence, and active particulate samplers to evaluate the effectiveness of a dense shelterbelt in reducing particulate emissions. A new protocol was developed for analysis of particulate matter (PM). In another study, a new parameterization method that included optimum temperature of extraction, extraction time, and sample size was developed to improve quantification of PM from livestock feedlots. Objective 2. Long-term monitoring of two common pre-emergent herbicides continued for the 15th year. In 2013 weak stability conditions not previously encountered influenced metolachlor and atrazine volatilization. A nitrous oxide (N2O) study during the third year compared the effects of soil N2O emissions from soil cropped to corn treated with enhanced efficiency fertilizers (EEFs) and conventional fertilizers. An eddy covariance N2O flux system was deployed in a corn field in Beltsville, MD. Preliminary N2O flux data were are being analyzed. In addition to the trace gas emissions survey, carbon dioxide (CO2) flux measurements were augmented to include two continuous soil CO2 flux measurement systems in the residue removal study to continue development of temperature sensitivity relationship for CO2 evolution. There is a need to evaluate and refine thermal-based two-source remote sensing models and tools for quantifying water use (evapotranspiration, ET) and root zone water availability and to improve water management strategies for vineyards. A multi-year study was initiated in April 2013 to conduct continuous intensive field experiments over vineyards to measure ET, root zone soil moisture, and biophysical data in concert with high resolution aircraft remote sensing imagery. Objective 3. Interactions of temperature, soil water availability, and nutrients were evaluated for corn and soybean using flux data across different growing season conditions. The effect of increasing minimum temperatures increases the nighttime respiration decreasing the photosynthetic rate the next day and is exaggerated by soil water deficits. Extreme temperatures at different phenological stages impact the rate of senescence and corn grain yield. A study is underway to evaluate the response of corn hybrids from different eras to temperature extremes in a controlled environment. Analysis of yield gaps in soybean from Iowa, Kentucky, and Nebraska showed that soil is a major determinate in the effect of variable weather on grain yield.
Hatfield, J.L. 2012. North American perspectives on potential climate change and agricultural responses. In: Hillel, D., Rosenzweig, C., editors. Handbook of Climate Change and Agroecosystems. Hackensack, NJ: Imperial College Press, World Scientific Publishing. p. 33-55.