For decades, scientists have used high-resolution reflectance spectra of minerals and soils to determine soil mineralogy, and to assess soil physical properties. A major breakthrough in these studies has been the use of visible-near infrared spectroscopy to develop quantitative calibrations for rapid characterization of soil nutrients and various physical properties of soils. The coupling of this technology with remote sensing data, georeferenced ground surveys, and new spatial statistical methods has resulted in the improved capability for large area soil assessments. Rapid spectroscopic soil analysis breaks the bottleneck of sample collection and lab testing, and permits the assessment of soil quality on a large number of representative samples covering expansive geographic areas.
Expansive spectral libraries continue to be developed for the interpretation and application of spectra to soils analysis. The spectral library approach allows calibrations based on small numbers of selected samples to be applied to the rapid analysis of thousands of samples. These studies overlap into many practical applications, including hazardous waste and environmental applications, agricultural analysis, hydrology, and soil fertility assessment.
Plant physiology-related applications include the analysis of plant tissue to assess water, nutrient and disease status. These applications are based on both canopy-level and leaf-level measurements of reflectance. Vegetative indices and the same type of quantitative modeling techniques used to develop soil nutrient calibrations have been used by researchers for determination of a wide range of plant biochemicals, including chlorophyll, xanthophylls (and other pigments), lignin, cellulose, and total nitrogen content (as related to protein concentration). In addition to analysis of photosynthetic biomass, these methods have also been applied to rapid analysis of seed composition for crops such as corn, wheat, rice, soybeans, and canola.
Crop photosynthetic modeling is another application in which ASD systems excel. These studies require the measurement of photosynthetic radiation above, below, and within a crop canopy. By measuring spectral irradiance, rather than just a single integrated reading, researchers can better study the interplay of the various secondary pigments.
The ability to accurately perform reflectance and radiometric measurements of vegetation and soil in the field is critical to all of these applications. The ASD FieldSpec® line of spectroradiometers offers a wide range of configuration options for both contact measurements (such as leaves or in a soil profile pit) and stand-off measurements (such as those needed to measure canopy reflectance). The FieldSpec uses a flexible fiber optic cable that can be used with many different accessories and configurations, giving researchers many options for acquiring critical data. ASD systems provide unmatched portability and spectral quality to allow researchers to work in some of the most remote regions of the planet while producing excellent spectral data..
Plant breeding researchers and genetics companies utilize ASD systems to allow characterization of new varieties and for production of the best quality seed. Our wide variety of sample probes allows the measurement of natural products without the need to grind or otherwise destroy the sample. Agriculture applications demand high throughput and low cost analyses. ASD systems typically can measure natural materials in as little as 5 seconds with no consumables and no sample preparation expense. Crops and animal feeds are also typical applications for ASD systems.
Scientists around the world use ASD instruments in their soils and crops research. Learn more by visiting one of the sections linked below.