Conclusions
Require an assimilation scheme with the characteristics of the Kalman-filter (ie. a scheme which can potentially alter the entire profile)
Require as linear forecasting model as possible to ensure stable updating with the Kalman-filter (ie. _-based model rather than a _-based model)
Updating of model is only as good as the models representation of the soil physics
Usefulness of near-surface soil moisture observations for improving the soil moisture estimation has been verified