Skip to main content
ARS Home » Southeast Area » Tifton, Georgia » Southeast Watershed Research » Research » Publications at this Location » Publication #208597
Title: Use of an Unmanned Aerial system for Site-Specific Management of Cotton

Author
item Sullivan, Dana
item FULTON, J - AUBURN
item SHAW, J - AUBURN
item BLAND, G - NASA GSFC

Submitted to: European Conference on Precision Agriculture Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/15/2007
Publication Date: 6/6/2007
Citation: Sullivan, D.G., Fulton, J.P., Shaw, J.N., Bland, G. 2007. Use of an Unmanned Aerial System for Site-Specific Management of Cotton. In: Proceedings of 6th European Conference on Precision Agriculture Proceedings, Skiathos, Greece, June 3-6, 2007.

Interpretive Summary: Thermal infrared remote sensing is a promising technology for precision agriculture management. However, in practice the expense associated with acquiring thermal infrared imagery of sufficient spatial resolution is oftentimes cost prohibitive. Current technological advances in small, unmanned aerial systems equipped with thermal infrared sensors may provide a solution for acquiring frequent, affordable and reliable imagery. The objective of the current study was to evaluate the utility of an unmanned aerial system equipped with a thermal infrared sensor for detecting cotton (Gossypium hirsutum L.) response to irrigation and crop residue management. Preliminary results show that the unmanned aerial system can be used to rapidly and more accurately depict variability in crop response compared to the more time consuming tasks of monitoring soil water content and stomatal conductance.

Technical Abstract: Remote sensing is a promising technology for site-specific management of in situ crop stress. In particular, compared to reflective regions of the spectrum, thermal infrared imagery is a more direct metric of crop response. However, in practice the expense associated with acquiring thermal infrared imagery of sufficient spatial resolution is oftentimes cost prohibitive. Current technological advances in small, unmanned aerial systems equipped with thermal infrared sensors may provide a solution for acquiring frequent, affordable and reliable imagery. The objective of the current study was to evaluate the utility of an unmanned aerial system equipped with a thermal infrared sensor for detecting cotton (Gossypium hirsutum L.) response to irrigation and crop residue management. Thermal infrared emittance was well correlated with canopy cover (r = -0.44, alpha < 0.05) and stomatal conductance (r= -0.48, alpha < 0.05). Data demonstrate that increasing canopy and stomatal conductance result in cooler canopies and a reduction in radiated heat (emittance). More importantly, because thermal infrared data were acquired near-instantaneously, emittance spectra proved more sensitive to variability in cotton response to treatment compared to the more time and labor intensive measurements of soil water content and stomatal conductance. Because canopy cover was variable at the time of remotely sensed data acquisition, an analysis of covariance was conducted to assess the impact of bare soil background contributions. Contributions of emittance from soil background were negligible, resulting in an estimable error of 1.5%. Data provide evidence that a thermal infrared sensor mounted on an unmanned aerial system can be used to identify small differences in canopy response to stress given a minimum canopy closure of 26%.