In a model ecosystem experiment Schulin and coworkers showed that soil can play a key role in the growth and evapotranspiration responses of young forest vegetation on elevated atmospheric carbon dioxide.Up to then soil had been neglected as a factor in the response of vegetation to elevated carbon dioxide.
In another model ecosystem experiment Schulin's team found that moderate topsoil pollution by heavy metals significantly reduced evapotranspiration of a young forest vegetation due to reduced root growth, in particular during periods of drought stress, and that roots compensated for metal toxicity in the topsoil by increasing water extraction from the subsoil. It could also be demonstrated that the biodegradable chelant EDDS can be used to enhance phytoextraction of polluting metals by mobilizing the metals in the soil, although metal-EDDS complexes are less available for uptake by roots through the symplastic pathway than free metal ions.