Sensors for Sustainable Management.

Plants respond to temperature, light, water and nutrients and use carbon dioxide in photosynthesis to produce vegetative biomass, grains and root crops. Over the past several decades, various crop canopy sensors have been developed to quantify crop parameters that were intended to improve management decisions that increase profitability and support environmental stewardship. Research using hyper-spectral instruments has generated many vegetation indices based on the correlation between reflectance data and measured plot or field parameters. Many of these vegetation indices were intended to calculate the degree and variation of photosynthesis and biomass production within a vegetation landscape. The red waveband has been commonly utilized to associate plant vigor with canopy chlorophyll content but is burdened by insensitivity at high leaf areas. For this reason, more versatile crop canopy sensors have been developed to monitor the red-edge portion of the spectra to provide chlorophyll content information. Up until recently, some hand-held research instruments, with red-edge capability, were comprised of a commercially available three-band sensor (Holland Crop Circle ACS-430 or Crop Circle ACS-470 fitted with red-edge and NIR wavebands), datalogger and power supply mounted to an extendable pole. New developments in handheld research instrumentation have integrated these components into an easy-to-use and ergonomically designed instrument. This new instrument is marketed by Holland Scientific as the RapidSCAN CS-45 crop canopy sensor. The RapidSCAN CS-45 integrates a built-in GPS, three band active optical sensor, a long-life lithium battery, and datalogger with large data storage capacity into a single handheld package. The RapidSCAN CS-45 can be configured with user loadable software apps that allow for real-time landscape mapping and fertilizer recommendation options.