Hochschule Ravensburg-Weingarten

Strukturbaum

Publikation

Autoren des Beitrags
Titel des Beitrags	Ecosystem response to human- and climate-induced environmental stress on an anoxic coastal lagoon (Etoliko, Greece) since 1930 AD
Titel veröffentlicht in ...	Journal of Paleolimnology
Verlag	Springer Science+Business Media	Verlagsort	Dordrecht
Erscheinungsjahr	2015	Seite (von - bis)	255-270	Publikations-Art	Peer-Reviewed Article	Band/Jahrgang/Volume	2015, Volume 53
URL :	http://link.springer.com/article/10.1007/s10933-014-9823-1
Abstract :	To better constrain the effects of anthropogenic impact on coastal wetlands with respect to natural variability, we here analyze annually laminated sediments from Etoliko lagoon (western Greece, Mediterranean Sea) spanning the last ~80 years. Sub-decadal-scale palynomorph (pollen and dinoflagellate cyst) and seasonal-scale palynomorph (microfacies and μ-XRF) analyses were carried out to investigate the evolution of the aquatic environment and the surrounding terrestrial ecosystem. Based on a robust age model, which was developed using varve counting and 137Cs dating, our results indicate that land-use changes have altered the vegetation dynamics and led to eutrophication of the aquatic environment particularly from the early 1980s onwards. In agreement with instrumental data and reports of fish mass mortality events, our varve composition and high-resolution element scanning data suggest that the ecosystem has been under unprecedented pressure since 1990 AD. In particular, the enhancement of anoxic conditions due to human-induced eutrophication is linked to high accumulation rates of organic matter, an increased presence of bacteria in sediment microfacies, and a decrease in the Fe/Mn ratio in the sediment. In addition, a change in varve type from calcite- to aragonite-dominated in 1983 and a higher Sr concentration during the 1990s indicate an increasingly saline aquatic environment. Comparison with meteorological data suggests that lower precipitation during a persistent positive North Atlantic Oscillation mode along with a gradual increase in mean summer temperature since the 1980s may have enhanced the saline conditions. These findings demonstrate that climate change can intensify the human impact on aquatic ecosystems. In conclusion, our analytical approach provides a valuable tool for evaluating the degree of degradation of Etoliko lagoon and the effectiveness of implemented management plans on the aquatic ecosystem, indicating that the efforts to restore its water circulation have only weakly contributed towards an environmental recovery.
Einrichtungen	Hochschule Ravensburg-Weingarten Bachelorstudiengang Physikalische Technik Masterstudiengang Umwelt- und Verfahrenstechnik Fakultät Technologie und Management Institut für Angewandte Forschung (IAF) Schwerpunkt Energie und Umwelt (IAF)
Beteiligte Personen	Klemt , Eckehard Prof. Dr. rer. nat.
Projekte	Radioökologische Studien und Untersuchungen Wissenschaftliche Veröffentlichungen