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2.2.3.1.4 Optical and spectrographic sensors

Microsystems already exist which can monitor and analyse plant growth using cameras and sophisticated software, however these are expensive and can only provide trend analysis, with little real-time data.  A useful system would monitor overall plant health and inform the farmer if growth is retarded, if physiological changes are evident, but not yet manifest on a visual level, and the best time to harvest.

Hyperspectral sensing (imaging spectrometry) was originally developed for mining and geology.  It measures reflected radiance (UV to infrared) as a set of hundreds to thousands of contiguous spectral bands.  From this data it is possible to distinguish between different mineral types.  However, it has more recently been applied to vegetation and can be used to determine plant coverage and growth rates.  Largely this technology depends on aerial or satellite imaging, however portable, ground-based sensors can also be used[i].

At present there do not appear to be any nanotechnology applications in this area.  However, advances discussed in other technology sectors (electronics and security) could be applied here eventually providing for cost effective and sensitive detection and analysis.