Nitrogen fertilization is one of the primary factors responsible for the increased yields in the United States in the past 15 years. Four levels of fertilization, 0, 67, 134, and 202 kg/hectare, providing a range from distinctly deficient to abundant have been selected from a long term fertilization experiment. The specific objectives of the experiment were to (1) determine the threshold of spectral detection of nitrogen deficiency and (2) determine kind and magnitude of changes in reflectance and thermal response as a function of level of nitrogen nutrition. Three replications were used.
Measurements were made at approximately 10 day intervals throughout the growing season with the Exotech 20C spectroradiometer over the 0.4 to 2.4 mu m wavelength range. Radiant temperature of the canopy was also measured. In addition to the standard agronomic data (leaf area index, etc.) leaf nitrogen and chlorophyll concentrations were determined. Also, leaf reflectance measurements were made on several dates.
The test took place in 1979.
The supporting docs include a brief summary of used instruments, a wavelength table (Wavelength_ASCII.txt), reflectance note and reflectance tables (ReflectanceTable206.txt and ReflectanceTableMulti.txt), and file format description (ExperimentDataFormat3.txt). The format description file is in ASCII format in lines of 80 characters.
This research dataset is part the Field Research Data Library that consists of over 200,000 spectral observations of soils and vegetation that have been collected since 1972 till 1991 as part of the research focused on vegetation and soils at the Laboratory for Applications of Remote Sensing (LARS) located at the Purdue University.
Cite this work
Researchers should cite this work as follows:
- Location: Purdue Agronomy Farm, West Lafayette, IN
- County: Tippecanoe
- Latitude/Longitude: 0402813N 0865927W
- Illumination: Solar
- Spectrometer: Exotech 20C-SW
- Wavelength Range: 0.40-2.40 um
- Experiment Type: Crops - Corn