RESUMEN
This paper aims to determine the content and bioaccumulation patterns of eight trace elements (Li, Cr, Co, As, Se, Cd, Pb and Hg) and one radioisotope (U) in kidney, liver and muscle tissues of two fish species (Squalius orpheus and Barbus strumicae) from Nestos River (northern Greece), and the potential human health risk due to the fish muscle consumption. Kidney and liver accumulate higher element concentrations, except Hg. The site closer to the river-mouth presents higher concentrations since it receives effluents from agricultural activities. The upstream station shows lower element concentrations, due to obstruction of the free transportation of sediments and suspended matter downstream the irrigation dam. The sediment inhabitant and feeder B. strumicae showed elevated concentrations compared to the water column resident S. orpheus. According to calculated hazard indices, the consumption of the fish edible tissue poses zero health risk in developing chronic undesired effects in humans.
RESUMEN
Worldwide, states are gazetting new Marine Protected Areas (MPAs) to meet the international commitment of protecting 30% of the seas by 2030. Yet, protection benefits only come into effect when an MPA is implemented with activated regulations and actively managed through continuous monitoring and adaptive management. To assess if actively managed MPAs are the rule or the exception, we used the Mediterranean and Black Seas as a case study, and retrieved information on monitoring activities for 878 designated MPAs in ten European Union (EU) countries. We searched for scientific and grey literature that provides information on the following aspects of MPA assessment and monitoring: ecological (e.g., biomass of commercially exploited fish), social (e.g., perceptions of fishers in an MPA), economic (e.g., revenue of fishers) and governance (e.g., type of governance scheme). We also queried MPA authorities on their past and current monitoring activities using a web-based survey through which we collected 123 responses. Combining the literature review and survey results, we found that approximately 16% of the MPA designations (N = 878) have baseline and/or monitoring studies. Most monitoring programs evaluated MPAs based solely on biological/ecological variables and fewer included social, economic and/or governance variables, failing to capture and assess the social-ecological dimension of marine conservation. To increase the capacity of MPAs to design and implement effective social-ecological monitoring programs, we recommend strategies revolving around three pillars: funding, collaboration, and technology. Following the actionable recommendations presented herein, MPA authorities and EU Member States could improve the low level of MPA monitoring to more effectively reach the 30% protection target delivering benefits for biodiversity conservation.