The recent history of the Tarquinia Salterns offers the opportunity to investigate parallel changes at the habitat and biodiversity levels

Abstract

1 - Salterns, although artificial habitats, can be considered as coastal wetlands from an ecological, functional and conservational point of view, according to the Ramsar Convention Bureau (1990). Salterns need to be actively managed to survive and, being at the interface between land and sea, experience the impacts of both environments. For these reasons their extension and quality are severely reducing along the Mediterranean coasts. 2 - The Tarquinia Salterns, on the Tyrrhenian coasts of central Italy, suffered a progressive habitat degradation starting with a serious flood in 1987 and getting worse from 1997, when the salt production ceased, to 2003, when a three years long project for their environmental rehabilitation was implemented (2003 – 2006). 3 - To recover the salterns habitat, the water flow, previously slow and laminar, was re-established. Also, the depth of the water column was reinstated through the removal of the excess of organic matter and mud deposited in the pans. 4 - The recent history of the Tarquinia Salterns provides the opportunity to carry on multi-disciplinary studies on the response of biotic and abiotic habitat components under the temporal oscillations of the environmental quality. A first result is that the recovery succeeded in restoring the abiotic conditions characterizing the salterns before their abandon and degradation. 5 - The biodiversity at the genetic level, investigated on the killifish Aphanius fasciatus, at the species level, as shown by the abundance of wintering birds; and at the community level, as assessed by the diversity of benthic community, was seriously affected by the environmental degradation. After the ecological recovery, the species and community reverted quickly to the previous diversity levels, while the genetic variation of the target killifish remained at the low levels reached in 2005. This confirms that the different aspects of biodiversity react similarly to the disturbance but display different times of recovery.