Author
MIDDLETON, E.M. - National Aeronautics And Space Administration (NASA) | |
CHENG, Y. - Collaborator | |
CAMPBELL, P. - University Of Maryland | |
HUEMMRICH, K.F. - University Of Maryland | |
ZHANG, Q. - Collaborator | |
LANDIS, D.R. - Collaborator | |
Kustas, William - Bill | |
Daughtry, Craig | |
Russ, Andrew - Andy |
Submitted to: International Symposium on Recent Advances in Quantitative Remote Sensing
Publication Type: Proceedings Publication Acceptance Date: 12/30/2014 Publication Date: 3/5/2015 Citation: Middleton, E.M., Cheng, Y., Campbell, P., Huemmrich, K.F., Zhang, Q., Landis, D.R., Kustas, W.P., Daughtry, C.S., Russ, A. 2015. Directional hyperspectral observations to detect plant stress with the PRI and SIF in a cornfield [abstract]. Proceedings of 4th Recent Advances in Quantitative Remote Sensing (RAQRS’IV). P. 9. Interpretive Summary: No interpretive summary needed. Technical Abstract: We examined the impact of drought stress and temperature on plant hyperspectral, fluorescence, and photosynthetic responses during the 2012 growing season at an experimental USDA (United States Department of Agriculture) cornfield in Beltsville, MD USA. The manipulations included 4 nitrogen (N) application levels (0%N, 50%N, 100%N, and 200%N) and two water availabilities (W, drip irrigation; or NW, no irrigation) to produce 8 treatments. Hyperspectral observations were made in the solar principal plane at 7 view zenith angles: nadir (0 dgrees) ±30, ±45, and ±60 degrees during morning and afternoon periods of 10 days throughout the season. Significant anisotropy was observed for the Photochemical Reflectance Index (PRI) and the far-red solar induced fluorescence (SIF760), and diurnal and seasonal trends were obtained. We found that the nadir viewing configuration was optimal to discriminate among these 8 field treatments when environmental stresses were strongly expressed due to extreme drought and high temperatures. Nadir observations remained sufficient to describe responses even under more favorable conditions with lower environmental stresses, although values were similar among all treatments (and viewing configurations). The diurnal differences for each indicator, as well as the degree of anisotropy observed, can be largely attributed to drought induced changes in the canopy geometries of the treatment plots. |