Exploitation of annual and perennial herbaceous species for the rehabilitation of a sand quarry in a Mediterranean environment.

Commercial seeds are widely used for re-vegetation interventions in Mediterranean areas. This seeds mostly consist of species and varieties of non-local provenance. The current practice relies mainly on forage or turf and fast growing species, even if it is often inefficient. Twenty-two local populations or commercial varieties of annual and perennial species belonging to the botanical families Leguminosae, Graminaceae and Compositae, were evaluated in a four-year field experiment, in order to investigate their potential in terms of establishment and persistence in the re-vegetation of an inactive sand quarry. Native species showed better performances than commercial varieties and encourage further actions for the valorisation of local plant biodiversity. Among legumes, the best adapted species was the perennial Lotus cytisoides that showed high persistence in combination with other positive traits. A few annual species i.e. Melilotus indica, Trifolium subterraneum and Ornithopus sativus performed well and persisted until the end of the experiment. Among perennial grasses, Cynodon dactylon survived to drought and low soil nutrients. Both native annual grasses Lolium rigidum and Aegilops geniculata performed very well during the first two years of experiments. Both forbs, the perennial Cichorium intybus and the annual Chrysanthemum coronarium did not guarantee a satisfactory persistence. Some native species were evidenced, that may play an important role in the re-vegetation of sand quarries and have good potential to be further characterised before introduction in the seed market.