Research Accomplishment Reports 2010

Characterizing Mass And Energy Transport at Different Scales

O. O. Wendroth
Department of Plant and Soil Sciences

 

Non-Technical Summary

Wide regions of Kentucky are covered by karst landscapes. Due to the soil genesis, soils are well-drained and exhibit a short connection to the groundwater. We need to quantify, how fast fertilizer nutrients and pesticides applied during agricultural management are transported downward with incoming rainfall, in order to avoid groundwater pollution. The purpose of this long-term-research project is to quantify surface and subsurface fluxes of water, chemicals, and solutes to better understand the water dynamics in these landscapes and to contribute to strategies for managing soils in a way that maintains water quality while minimizing environmental risks. Moreover, since sinkholes and their associated hillslopes and catenas can differ in size and geometry, elevation, and soil profile features, rules for generalizing transport processes for different scales need to be derived.

2010 Project Description

1. Short-term Outcomes Ph.D. Students mentored (main advisor): 5 Ph.D. Students graduated (main advisor): 2 M.S. Students mentored (main advisor): 1 M.S. Students graduated (main advisor): 1 External grants: $ 335,000 ($324,000 were year 2 of a USDA project)

2.Outputs Report to Kentucky Small Grain Growers' Association: "Winter Wheat Development, Grain Yield and Soil Water and Nitrogen Dynamics in a Farmer's Field in Western Kentucky" by Ole Wendroth, Greg Schwab, Lloyd Murdock, and Dennis Egli Ole Wendroth, Vicente Vasquez, and Christopher J. Matocha. 2010. Spatial Variation Scales of Rainfall Characteristics and Bromide Leaching. Poster. American Geophysical Union, Fall 2010, Dec. 13-18, San Francisco. Wendroth, O. 2010. Combined space-time state space model for field soil water storage. Oral Presentation. Annual Meeting, ASA-CSSA-SSSA, Oct. 30 - Nov. 4, 2010, Long Beach, California. Wendroth, O., C.J. Matocha, and V. Vasquez. 2010. Field-Scale Bromide Transport as a Function of Rainfall Amount, Intensity and Application Time Delay. Poster. 19th World Congress of Soil Science, IUSS, Brisbane, Australia, Aug. 01-06, 2010. Wendroth, O., V. Vasquez, and C.J. Matocha. 2010. Impact of rainfall amount, intensity, and time lag on leaching behavior of a surface-applied Bromide tracer. Oral Presentation. Kentucky Water Resources Annual Symposium, March 22, 2010, Griffin Gate Marriott Resort, Lexington, KY

3. Activities Chair of Precision Resources Management Committee, College of Agriculture, University of Kentucky; Program development and review of PRM proposals Associate Editor Soil Science Society of America Journal Associate Editor Vadose Zone Journal Editorial Board Member: Soil and Tillage Research; Journal of Plant Nutrition and Soil Science Manuscript reviews in 2010: 46

4. Milestones

Derived the spatial range of representativity for bromide tracer concentration at the field scale.

Found out that the higher the rainfall intensity, the lower the amount of rainfall, and the longer the time between surface chemical salt and subsequent rainfall, the shallower the leaching depth of surface-applied salt.

Wheat research in Kentucky: Found out, that crop indices monitored in spring time have a closer relationship to crop yield variability than deterministic model-based predictions.

Established a new graduate course PLS 655 at the University of Kentucky in "Spatial and Temporal Statistics".

2010 Impact

Research results show that farmers should pay attention to rainfall forecast before applying fertilizers or pesticides, and if they do they contribute to water quality. New experimental designs allow to study soil processes on-site in natural landscapes and farmers' fields. Using crop sensors in spring time, farmers can save resources by site-specifically applying nitrogen fertilizer. The new course in Spatial and Temporal Statistics has an impact on higher level education in agricultural sciences.

2010 Publications

Wendroth, O., K.C. Kersebaum, G. Schwab, and L. Murdock. 2011. Spatial relationships of soil properties, crop indices and N application pattern with wheat growth and yield in a field. In: Ahuja, L., and L. Ma (Eds.) Methods of Introducing System Models in Field Research, Volume 2 in the Advances in Agricultural System Modeling Series, ASA-SSSA-CSSA, Madison, WI. (in press).

Miller, J.O., A.D. Karathanasis, and O.O.B. Wendroth. 2010. In-situ colloid generation and transport in 30 year old mine soil profiles receiving biosolids. Intl. J. Mining, Reclam. Environ. 24:95-108.

Wendroth, O., S. Koszinski, and V. Vasquez. 2010. Soil spatial variability. In: Huang, P.M., Y.C. Li, and M.E. Sumner (Eds.) Handbook of Soil Science, 2nd ed., CRC Press. (in press).

Wendroth, O., E.L. Ritchey, S. Nambuthiri, J.H. Grove, and R.C. Pearce. 2010. Spatial variability of soil physical properties. In: Gliński, J., J. Horabik, and J. Lipiec (Eds.), Encyclopedia of Agrophysics. Springer, Heidelberg, Germany. (in press).