I’m interested in the interactions between soil, water and vegetation in drylands, in both natural and agricultural ecosystems. Our goal is to understand how the basic processes and feedbacks influence how the system changes in time, and how this knowledge can be used to control those systems. ​

The common theme between my different research projects is land/ecosystem degradation caused by human activity.

Our research is based on “simple” mathematical models, that strive to capture the essential physical processes, while providing deep insight into the dynamics of the system. Some of the tools we use in the modeling of environmental questions come from dynamical systems, statistical physics and optimal control theory.

We are recruiting excellent students to our group! Here you can find some more detail on our current projects.


Soil salinization

Every week, the world loses an area greater than Manhattan to salt-related soil degradation. It is estimated that 20% of all irrigated lands are affected by salinity, with an even higher fraction of salt-degraded soils in arid and semiarid regions. Salt accumulation in the soil, usually induced by insufficient drainage and poor-quality irrigation water, imposes severe restrictions on food production.

Some of the questions we’d like to answer are: On what time scales the salinization process occurs, and what is the effect of a drier and more extreme climate on the salt buildup? What are the critical thresholds for (irreversible) soil degradation? How can we rehabilitate a degraded soil by making optimal use of the resources available? What role can treated wastewater have on dryland agriculture that is sustainable with respect to the ecosystem services? ​

Nutrient dynamics

Nitrogen management is of critical importance to food security and environmental sustainability. Because of artificial fertilizers, we have seen a sharp increase in agricultural production in the last century. However, the same nitrogen available to plant uptake, can polute the groundwater, streams and lakes, and be released as nitrous oxide, a potent greenhouse gas.

We would like to understand how the nonlinear dynamics of nitrogen and carbon cycling is influenced by the hydrological cycle. In particular, we would like to study the influence of random rainfall events and a changing climate in driving these cycles.