Assessing the risks to Mediterranean islands ecosystems from non-native plant introductions.

Peer Reviewe

A case study of artificial reefs as a potential tool for maintaining artisanal fisheries in the French Mediterranean Sea

International audienceThe aim of this study was to obtain information allowing an initial assessment of the potential of French Mediterranean artificial reefs (ARs) as a management tool to aid artisanal fishermen. The study focuses on 3 ARs located along the Gulf of Lion coastline in the French Mediterranean Sea. At the end of spring 2012, experimental fishing with trammel nets was conducted at ARs and natural rocky areas (NRs) at various distances from the ARs/NRs (0, 300 and 900 m). The yields of fish and invertebrates were analyzed at the AR sites to identify significant changes along a distance gradient and to determine whether there was a significant difference between ARs and NRs. The AR yields of species preferring rocky substrates were generally higher between 0 and 300 m from the ARs than beyond 300 m, whereas the yields of species preferring sandy substrates or of invertebrates did not differ between 0 and 900 m from the ARs. Furthermore, the AR yields were equal to the NR yields or were between 1.5- and 1.8-fold higher than the NR yields. Overall, this study indicates that success varied by species, fishing locality and distance from the reef. ARs could be a potentially effective tool for enhancing artisanal fishing along the French Mediterranean coasts. However, it would be necessary to establish management measures to avoid overexploitation. For instance, in terms of the configuration of the AR areas in a given locality, a no-take area could be established within a radius of 300 m around the ARs

Exploring the potential of biobeds for the depuration of pesticide-contaminated wastewaters from the citrus production chain: Laboratory, column and field studies

The high wastewater volumes produced during citrus production at pre- and post-harvest level presents serious pesticide point-source pollution for groundwater bodies. Biobeds are used for preventing such point-source pollution occurring at farm level. We explored the potential of biobeds for the depuration of wastewaters produced through the citrus production chain following a lab-to-field experimentation. The dissipation of pesticides used pre- or post-harvest was studied in compost-based biomixtures, soil, and a straw-soil mixture. A biomixture of composted grape seeds and skins (GSS-1) showed the highest dissipation capacity. In subsequent column studies, GSS-1 restricted pesticides leaching even at the highest water load (462 L m(-3)). Ortho-phenylphenol was the most mobile compound. Studies in an on-farm biobed filled with GSS-1 showed that pesticides were fully retained and partially or fully dissipated. Overall biobeds could be a valuable solution for the depuration of wastewaters produced at pre- and post-harvest level by citrus fruit industries. (C) 2012 Elsevier Ltd. All rights reserved

Hexavalent chromium leads to differential hormetic or damaging effects in alfalfa (Medicago sativa L.) plants in a concentration-dependent manner by regulating nitro-oxidative and proline metabolism

Chromium has been proven to be extremely phytotoxic. This study explored the impacts of increasing Cr(VI) exposure (up to 10 mg L−1 K2Cr2O7) on the growth and development of alfalfa plants and adaptation responses employed, in an environmentally relevant context. The threshold concentration of K2Cr2O7 in irrigation water beyond which stress responses are initiated is 1 mg L−1. Lower Cr(VI) exposure (0.5 mg L−1 K2Cr2O7) induced hormesis, evident through increased biomass and larger leaves, likely mediated by increased NO content (supported by elevated NR enzymatic activity and overexpression of NR and ndh genes). Elevated Cr(VI) exposure (5 and 10 mg L−1 K2Cr2O7) resulted in reduced biomass and smaller leaves, and lower levels of photosynthetic pigment (10 mg L−1 K2Cr2O7). Higher levels of lipid peroxidation, H2O2 and NO contents in these plants suggested nitro-oxidative stress. Stress responses included increased SOD and CAT enzymatic activities, further supported to some extent by MnSOD, FeSOD, Cu/ZnSOD and CAT transcripts levels. GST7 and GST17 gene expression patterns, as well as proline content, P5CS enzymatic activity and corresponding P5CS and P5CR gene expression levels emphasized the role of proline and GSTs in the adaptation responses. Results highlight the importance of managing Cr(VI) levels in irrigation water. © 2020 Elsevier Lt