Soil-Plant Spectral Diagnostics Laboratory
The Soil-Plant Spectral Diagnostics Laboratory builds on over ten years of development by World Agroforestry Centre (ICRAF) of infrared spectroscopy techniques for rapid soil and plant analysis and their application to large area surveillance of land health. The laboratory has recently extended its research on photon-based techniques to x-ray and laser applications for rapid prediction of soil functional properties. The laboratory serves as the main analytical centre for the Africa Soil Information Service (AfSIS) (www.AfricaSoils.net) as well as supporting an increasing number of land management projects in Africa.
The overall goals of Soil-Plant Spectral Diagnostics Lab are to:
(i) Develop soil-plant spectral analytical methods and diagnostic tools for rapid and reliable assessment of soil and plant health; and
(ii) Demonstrate their application for evidence-based agroforestry and land management policy and practice in developing countries.
The nearer term goals are to:
(a) Develop high-throughput spectral analytical methods requiring minimal use of sample preparation and chemicals.
(b) Apply spectral analytical techniques in decision support tools for diagnosis of soil and plant health problems in the tropics.
(c) Provide high quality spectral analytical services for the Globally Integrated African Soil Information Service (AfSIS) and other CGIAR research projects, including serving as a spectral reference laboratory.
(d) Strengthen national capacity in spectral diagnostic methods and their application for improved land management at technical, graduate and postgraduate levels.
Infrared spectroscopy methods in use span visible, near infrared and mid infrared diffuse reflectance spectroscopy and attenuated total reflectance spectroscopy. The ICRAF laboratory supports a network of infrared spectroscopy laboratories located in national institutions in Africa, currently: Cote D'Ivoire, Kenya, Malawi, Mali, Mozambique, Nigeria, and Tanzania. An online soil spectral prediction service will be launched shortly to support this network.
New techniques in progress in the spectral laboratory include soil particle size and aggregate stability analysis using laser diffraction spectroscopy; quantitative mineral composition using bench top x-ray diffraction spectroscopy; and total element composition using total x-ray fluorescence spectroscopy.
The spectral laboratory provides capacity building and advisory services to both developing and developed countries. For example, ICRAF's standard operating procedures were recently provided to the US National Soil Survey Center (NSSC) to set up a national soil mid-infrared spectroscopy system. ICRAF is also helping to design a soil monitoring system for the Global Agricultural Monitoring System being led by the Bill & Melinda Gates Foundation and Conservation International.
There is growing demand for soil spectral analytical and calibration services, research and technical support, and capacity building as our soil health baselines become incorporated into an increasing number of sustainable land management projects and programmes. There is strong interest in climate change mitigation and adaptation projects in our protocols for measuring and monitoring soil carbon stocks in agricultural landscapes (http://www.unep.org/climatechange/carbon-benefits/). Conservation groups and other stakeholders are beginning to recognize that monitoring of soil health in landscapes is now feasible at low cost. Projects are also underway in partnership with the private sector to develop spectrally-based soil testing services to smallholder farmers.
Plans to scale out the soil spectral techniques across CGIAR centres have been incorporated into the CGIAR Research Programme 5 on Water, Land & Ecosystems, within which ICRAF leads the Information Systems Strategic Research Portfolio, and we are already receiving requests to help other CGIAR centres to set up satellite laboratories.
Future needs include development of global calibration libraries, capacity building in soil spectral methods and soil health surveillance across the tropics; development of lower cost and field-based spectral applications, and advancement of intelligent scientific work flows and digital mapping techniques that explicitly express uncertainties.