Rehabilitation of abandoned areas from a Mediterranean nature reserve by Salicornia crop: Influence of the salinity and shading

In Reserva Natural de Castro Marim e Vila Real de Santo Antonio (SE of Portugal), most of the salt marshes and saltpans are abandoned contributing to their degradation and, consequently, alteration of some ecological conditions. Rehabilitation of these areas by a Salicornia crop can contribute to their economic and environmental improvement by stimulation of biogeochemical processes and biomass commercialization. However, the development of agro-techniques adjusted to species and variable environmental conditions from Mediterranean are needed in order to improve the Salicornia crop. This study aimed to evaluate: i) potential use of seedlings from greenhouse in the field cultivation; and ii) survival, growth and yield of Salicornia under shading and different salinity conditions of the soils and irrigation waters. Autochthonous Salicornia species (S. ramosissima and S. patula) were tested. Germination tests under controlled conditions and in situ mesocosm assays were carried out. Assays were realized with a low density of seedlings from natural conditions and greenhouse, and soils and waters from estuary both with different salinities. Intermediate and high salinities (25-45dS/m) affected only S. patula germination. In general, Salicornia growing in soils with low salinity had great fresh biomass accumulation independently of seedling source (from natural conditions and greenhouse) and/or growing season. The shading seems to improve the fresh biomass accumulation and yield. Under Mediterranean conditions, the transplantation of Salicornia from greenhouse to the field was a promising technique, independently of the salinity conditions. This study demonstrated that the abandoned and saline areas can be rehabilitated by a sustainable crop of Salicornia.project "Cultivo sustentavel de halofitas na Reserva Natural do Sapal de Castro Marim e Vila Real de Santo Antonio" from Programa POAlgarve 21 [ALG-02-0931-FEDER-000022]