Effects of Vineyards and Olive Plantations on Reptiles in a Mediterranean Agroecosystem

Morphological variations and demographic responses of the Mediterranean pond turtle Mauremys leprosa to heterogeneous aquatic habitats

Human activities affect terrestrial and aquatic habitats leading to changes at both individual and population levels in wild animal species. In this study, we investigated the phenotype and demographics of the Mediterranean pond turtle Mauremys leprosa (Schweigger, 1812) in contrasted environments of Southern France: two peri-urban rivers receiving effluents from wastewater treatment plants (WWTP), and another one without sewage treatment plant. Our findings revealed the presence of pesticides and pharmaceuticals in the three rivers of investigation, the highest diversities and concentrations of pollutants being found in the river subsections impacted by WWTP effluents. Principal component analysis and hierarchical clustering identified three levels of habitat quality, with different pollutant concentrations, thermal conditions, nutrient, and organic matter levels. The highest turtle densities, growth rates, and body sizes were estimated in the most disturbed habitats, suggesting potential adult benefits derived from harsh environmental conditions induced by pollution and eutrophication. Conversely, juveniles were the most abundant in the least polluted habitats, suggesting adverse effects of pollution on juvenile survival or adult reproduction. This study suggests that turtles living in polluted habitats may benefit from enhanced growth and body size, at the expense of reproductive success.

Environmental challenges of intensive woody crops: The case of super high-density olive groves

Super high-density olive groves (>800 trees ha^-1) are rapidly expanding in olive oil producer countries, which entails a strong modification of the olive growing system with important agronomic, economic, sociocultural, and environmental consequences. Among them, the latter is particularly unknown. The aim of this paper is to bring the attention on the environmental impacts of super high-density olive groves, by systematically reviewing the current evidence and identifying knowledge gaps yet to be filled. As a result, we can argue that new super high-density olive plantations reduce habitat heterogeneity and complexity, and the younger trees of these plantations impoverish habitat quality for farmland biodiversity. In addition, the high input use (e.g. phytosanitary treatments, fertilisers and water supply) may entail ecological impacts as well. Therefore, we conclude that i) new highly intensive olive groves should be limited to areas with lower ecological value; ii) consumers should have more information concerning how is produced the olive oil they buy, including the environmental impacts produced; iii) agricultural policies should be reformulated following the provider-gets principle; iv) input use (fertilisers, pesticides, water, etc.) should be gradually optimised to reduce the environmental impact; and finally, v) more research is necessary to foster decisions based on science.