Water p-ROOF is a project born because of the COVID pandemics and it is the result of combining two projects that were funded by the Planetary Wellbeing Initiative of the Universitat Pompeu Fabra. The aim of this new project is to create a small experimental station for growing plants on the roof of the Mercè Rodoreda Building, in the Ciutadella Campus of the UPF. These facilities will consist of some large planters and a small station of 60 lysimeters, which will be used initially to grow drought-tolerant cereals under different water regimes. These experiments will be comparable with those being performed within the project RANDROPS and will give us an idea of plant's physiological responses to water stress and differential production of biogenic silica in relation to water availability. The results of these experiments will be used to build a methodology to infer water regimes for dryland crops in the past, thus allowing us a better reconstruction of the beginning and development of agriculture in dry areas of the world.  This is part of the PhD research of Francesca D'Agostini who is pursuing a joint PhD between the Department of Humanities of UPF and the GAIA doctoral school in Biodiversity, Agriculture, Food, Environment, Earth, Water of the University of Montpellier.