Recent habitat degradation in karstic Lake Uluabat, western Turkey : a coupled limnological-palaeolimnological approach

The Ramsar site of Lake Uluabat, western Turkey, is suffering from eutrophication, industrial pollution and water abstraction, and its naturally-fluctuating water levels are now managed artificially. Here we combine monitoring and palaeolimnological techniques to investigate spatial and temporal limnological variability and ecosystem impact, using an ostracod and mollusc survey to strengthen interpretation of the fossil record. A combination of low invertebrate Biological Monitoring Working Party scores (<10), low ostracod and mollusc diversity across the lake basin, and the dominance of eutrophic diatoms confirms the lake’s poor ecological status. Analysis of organic and carbonate content, diatoms, stable isotopes, ostracods and molluscs in a radiometrically-dated sediment core (ULU20A) indicates a 20th century trend towards increased sediment accumulation rates and eutrophication which was probably initiated by deforestation and agriculture. The most marked ecological shift occurs in ca. 1962, however. A subtle rise in diatom-inferred total phosphorus, coupled with an inferred reduction in submerged aquatic macrophyte cover, accompanies a major increase in sediment accumulation rate; an associated marked shift in ostracod stable isotope data indicative of reduced seasonality and a change in hydrological input indicates impact from artificial water management practises, all of which appears to have culminated in the sustained loss of submerged macrophytes since 2000. We discuss the implications for lake restoration in the context of the EU Water Framework Directive. In a wider context, the results have important implications for the conservation of shallow karstic lakes, the functioning of which is still poorly understood

Bridging Biodiversity Conservation Objectives with Landscape Planning Through Green Infrastructures: A Case Study from Sardinia, Italy

The definition of Green Infrastructure (GI) provided by the European Commission in its 2013 Communication “Green Infrastructure: Enhancing Europe’s Natural Capital” regards GI as a network having the Natura 2000 sites at its core, able of delivering numerous ecosystem services, and “strategically planned”, stressing the importance of GI in integrating ecological connectivity, biodiversity conservation, and multi-functionality of ecosystems. Consequently, the spatial identification and management of GI is an important issue in planning, and especially in landscape planning as understood in the European Landscape Convention. Building on a previous work by Arcidiacono et al. (2016), this paper tests a methodology whereby the spatial configuration of a GI is identified in relation to four aspects (conservation value, natural value, recreation value, anthropic heritage) which summarize the multifaceted character of landscape. The methodology is tested in the Italian region of Sardinia, by applying it in the coastal landscape units defined in the Regional Landscape Plan currently in force which overlap the metropolitan area of Cagliari. We argue that this methodology can effectively help integrate biodiversity conservation objectives into spatial planning by implementing article 10 of the Habitats Directive, stating that relevant features of the landscape should be managed so as to improve the ecological coherence of the Natura 2000 network

Impacts of marine aquaculture at large spatial scales: Evidences from N and P catchment loading and phytoplankton biomass

While several studies point at off-shore aquaculture as a possible source of impacts on the local marine environment, very few have analysed its effects at large scales such as at the bay, gulf or basin levels. Similar analyses are hampered by the multiple sources of disturbance that may concomitantly affect a given area. The present paper addresses these issues taking the Gulf of Castellammare (Southern Tyrrhenian Sea) as an example. Nitrogen (N) and phosphorous (P) loads were calculated for the period 1970e2007, and compared to chlorophyll-a concentration as measured inside and outside the Gulf over the same period. Results indicate that N and P catchment loading has constantly decreased because of improved environmental management. Nevertheless, nutrient concentration in the Gulf has steadily increased since the establishment of aquaculture facilities in 1999. Chlorophyll-a concentration followed this trend, showing a marked increase from 2001 onwards. In the same period, chlorophyll-a concen- trations measured inside and outside the Gulf have significantly diverged. As all the other possible causes can be ruled out, aquaculture remains the sole explanation for the observed situation. This paper demonstrates for the first time ever that off-shore aquaculture may affect the marine ecosystem well beyond the local scale and provides an additional element of concern to be kept into consideration when allocating oceans’ space for new fish-farming activities