|ARMSTRONG, KEVIN - John Deere Technology Innovation Center|
|HENDRICKSON, LARRY - John Deere Technology Innovation Center|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/22/2014
Publication Date: N/A
Interpretive Summary: Farmers currently manage inputs in spatially variable fields using measured variation in soil properties. Crop yields often vary due to topographic variation and including this topographic effect in management recommendations should improve input use efficiency. A study was conducted in Nebraska to better understand the relationship between soil properties and topographic position on crop yield and to begin developing recommendations for managing irrigation using this information. Soil properties were determined at select locations across three fields to a depth of three feet. Water redistribution along a topographic gradient was also monitored using a Field Connect (Deere & Company, Moline, IL) sensor. The analysis of several years of crop yield data along with the measured soil properties and topographic information suggests that inputs can be managed more efficiently by including topographic information.
Technical Abstract: Precision irrigation management is currently accomplished using spatial information about soil properties through soil series maps or electrical conductivity (EC measurements. Crop yield, however, is consistently influenced by local topography, both in rain-fed and irrigated environments. Utilizing a combination of both soil properties and local topography has been hypothesized to provide a more detailed description of crop yield patterns, this influencing irrigation management. A study was developed in Fall 2013 on two fields in Western, NE (both planted to what) and one field in Eastern, NE (planted to soybean) to investigate the respective roles of soil properties and local topography in determining crop yield. Previously collected EC measurements along with local topography were used to guide sampling of 32 soil cores (100 cm deep) collected on each field. Field Connect (Deere & Company, Moline, IL) systems were further installed to monitor soil moisture variability. Combined with multi-year, data analysis suggests irrigation management can be improved by including local topography information. We believe this has implications not only on irrigation application, but also for monitoring soil moisture variability.