Natural and human-induced environmental change in southern Albania for the last 300years — Constraints from the Lake Butrint sedimentary record

Abstract

a b s t r a c t a r t i c l e i n f oA sediment core from Lake Butrint in southwestern Albania contains an annually-layered sequence covering the last ∼ 300 years. It provides thus an exceptionally well-dated time series to study past climate-driven environmental changes, as well as anthropogenic perturbations along the coast of the Ionian Sea. The varves are composed of organic-rich carbonate couplets and detritus-dominated clay layers. The first are deposited during spring-to-fall, and reflect the chemistry of the lake, which, in turn, is sensitive to 1) the relative importance of marine versus freshwater inputs, 2) relative evaporation rates, and 3) the productivity cycle within the lake. The detrital laminae are deposited during winter, reflecting precipitation and runoff conditions during the wet season. A 2-3‰ stable carbon isotope ratio shift in both bulk organics and authigenic carbonates was attributed to increasing eutrophication towards the end of the 20th century, and validated by historical and instrumental data. An increase in the δ 18 O of authigenic carbonates by more than 8‰ indicates the progressive salinization of the lake, which can primarily be attributed to man-made perturbations that reduced the freshwater input to the lake and/or enhanced the exchange with seawater from the nearby Ionian Sea. A recent increase in the relative evaporation versus precipitation rates may have additionally contributed to the observed 18 O enrichment in the Lake Butrint carbonates. The interdecadal cyclicity in the thickness of the detrital laminae seems to be at least partially controlled by NAO and/or ENSO-like phenomena that modulate precipitation patterns in the eastern Mediterranean. Thus, this study demonstrates the potential of combining microstratigraphic and stable isotopic tools to disentangle anthropogenic and natural environmental changes in Lake Butrint, validated by historical records.

Analysis of Long-Term Water Level Variation in Dongting Lake, China

“…However, because of the combined impact of climatic change and anthropogenic activities, many lakes around the world are changing [5][6][7][8]. Climate warming and anthropogenic activities (e.g., overexploitation, dams and diversions) will adversely affect water quality and quantity.…”

“…In some regions, wetlands area will decrease or disappear and water tables will decline. Habitats for wetland species will be changed in some lakes [5][6][7][8]. These changes may affect the availability of fresh water and regional eco-environments, thus having a critical influence measured inflow and outflow discharge data from 2003 to 2014 and two scenarios simulated by our numerical model.…”

Mapping Dynamics of Inundation Patterns of Two Largest River-Connected Lakes in China: A Comparative Study

“…In recent years, many freshwater lakes throughout the world have been undergoing dramatic changes in their water inundation and morphology [3][4][5]. These changes greatly affect the spatial availability of freshwater resources, which can disturb terrestrial and aquatic environments, thereby altering wildlife ecosystems and posing threats to regional sustainable development [6,7]. Therefore, understanding spatio-temporal inundation patterns and processes are critical for lake ecological conservation, flood/drought prevention and water resource management and planning [8][9][10].…”

Laminated lake sediments in northeast Poland: distribution, preconditions for formation and potential for paleoenvironmental investigation

“…Despite numerous studies of lake sediment cores from other Polish lakes, only short laminated sections were occasionally found and are related to early stages of lake development (Więckowski 1978). Recently, an intermittently laminated core was reported from Lake Miłkowskie in the Land of Great Masurian Lakes (Wacnik 2009), and (Petterson 1996, Zillén et al 2003; 2 Finish lakes (Ojala et al 2000); 3 Tougjärv (Veski et al 2004); 4 Loch Ness (Cooper and O'Sullivan 1998); 5 Loe Pool (Simola et al 1981); 6 Lake Diss Mere (Peglar et al 1984); 7 Belauer See (Dörfler et al 2012); 8 Hämelsee (Merkt and Müller 1999); 9 Woseriner See (Dreibrodt et al 2002); 10 Sacrower See (Lüder et al 2006); 11 Lake Goscią _ z (Ralska-Jasiewiczowa et al 1998); 12 Meerfelder Maar (Brauer et al 1999); 13 Holzmaar (Zolitschka et al 2000); 14 Frickenhauser See (Enters et al 2006); 15 Steisslinger See (Eusterhues et al 2002); 16 Ammersee (Czymzik et al 2010); 17 Baldeggersee (Lotter et al 1997); 18 Soppensee (Lotter 1989); 19 Lac Pavin (Stebich et al 2005); 20 Lac Bramant (Guyard et al 2007); 21 Lac D'Annecy (Brauer and Casanova 2001); 22 Seebergsee (Hausmann et al 2002); 23 Silvaplana See (Leemann and Niessen 1994); 24 Mondsee (Wolff et al 2006); 25 Längsee (Schmidt et al 2002); 26 Lake Butrint (Ariztegui et al 2010); 27 Lake Montcortés (Corella et al 2011); 28 Lake La Cruz (Romero-Viana et al 2008); 29 Lake Zoñar (Martín-Puertas et al 2009) conditions for deposition of laminated sediments in meromictic Lake Suminko in the Kashubian Lakeland were investigated by Tylmann et al (2012).…”