The potential of spectral reflectance: can we "see" the legacy effects of soil from biomass crops?

Worldwide soils are needed to produce food, consumables and bioenergy. The increased pressure on availability of agricultural land, and secondly, intensification of crop production can cause degradation of soil biodiversity and loss of soil function, hence damage soil ecosystem services. It is therefore imperative to improve biomass crop management in order, not only to increase production for energy, but also to maintain high quality living soils. Here we test the effects of different biomass crops on soil nutrient availability, soil biodiversity, soil disease suppressive capacities and whether we can use spectral reflectance of plant to monitor such effects on the soil. To accommodate this aim, we used soils from a 5-year biomass crop trial on which we grew a commonly used crop in agriculture: winter wheat. The first results of this study show that the effects on this subsequent crop are highly biomass crop-specific. We find a strong positive effect of some biomass crops on soil functioning and crop growth, while others increase vulnerability to diseases (poster Maarten Schrama). These changes are also reflected in the plant spectral measurements. Our results thus show that these legacy effects of biomass crops may be important for evaluation of biomass crop management; both in ecological and economical terms. Using spectral reflectance measurements could be a useful and tool to track such effects.