El yali national reserve: A system of coastal wetlands in the southern hemisphere affected by contemporary climate change and Tsunamis

El Yali is a complex wetlands system composed by more than 14 waterbodies, located in central Chile and delimited by two basins of the most important rivers of the region. Among the waterbodies is a coastal lagoon, some estuaries, artificial wetlands, salt mine and inner lagoons that were coastal lagoons in the past but due to tectonic processes have been moved and raised to their current location. The damming of the river that delimits the system to the south in 1968 cutoff the natural the sedimentary supply to the extensive beach and dunes, leaving the wetlands in a situation of vulnerability before climate change and variability, anthropic pressure, ocean swells and tsunamis. In the present chapter is illustrated the degradation that the wetlands system is suffering, by means of the estimation of tendencies of the long term records available in the zone, antecedents about its natural history, anthropic pressure and natural disasters like earthquakes, tsunamis, ocean swells and ENSO, along with field monitoring that has been carried out with the objective of implementing an ecological restoration. These antecedents show a decrease of precipitations and river discharges, an increase of ambient temperature and sea surface temperature, a rising of sea level and a change of the incident waves.