Coastal upwelling in the Rías Bajas, NW Spain: Contrasting the benthic regimes of Rías de Arosa and de Muros

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Modéliser le potentiel des régions de basses altitudes d'Europe Occidentale pour le retour du lynx eurasien (Lynx lynx)

In the last forty years, tolerance of anthropic environment has allowed large carnivores to recolonize and expand their distribution in Western Europe. To assess the full potential and consequences of this return, habitat use and landscape modeling are particularly useful tools that allow conservationists to come up with reliable prediction, and policy makers to anticipate management planning. The considerable power of dispersal and important space requirements of these species necessitate large-scale modeling, but it is essential to work in parallel at very fine scale, as carnivores’ impact on human societies is mostly felt at local level. Management of large carnivores must therefore be multi-scalar, with different decisions taken at multiple levels. With the return of the Eurasian Lynx (Lynx lynx) to lowland Western Europe, in regions of relatively high human densities, conservation- planning decisions must be knowledge based. Different approaches will be followed to analyze data at finer and larger scales. These include differential distribution and tolerance of lynx to fragmentation and anthropization, influence of landscape on lynx predation and the development of a conceptual model aiming at responding efficiently to conflicts with human populations. Results will permit the development of a lowland Western Europe habitat model, and to propose conservation measures adapted to the return of this emblematic carnivore. Results will permit the development of a lowland Western Europe habitat model, and to propose conservation measures adapted to the return of this emblematic carnivore

Drought tolerance in selected aerobic and upland rice varieties is driven by different metabolic and antioxidative responses

Main conclusions: Sugar-mediated osmotic acclimation and a strong antioxidative response reduce drought-induced biomass loss at the vegetative stage in rice. Abstract: A clear understanding of the physiological and biochemical adaptations to water limitation in upland and aerobic rice can help to identify the mechanisms underlying their tolerance to low water availability. In this study, three indica rice varieties-IR64 (lowland), Apo (aerobic), and UPL Ri-7 (upland)-, that are characterized by contrasting levels of drought tolerance, were exposed to drought at the vegetative stage. Drought-induced changes in biomass, leaf metabolites and oxidative stress markers/enzyme activities were analyzed in each variety at multiple time points. The two drought-tolerant varieties, Apo and UPL Ri-7 displayed a reduced water use in contrast to the susceptible variety IR64 that displayed high water consumption and consequent strong leaf dehydration upon drought treatment. A sugar-mediated osmotic acclimation in UPL Ri-7 and a strong antioxidative response in Apo were both effective in limiting the drought-induced biomass loss in these two varieties, while biomass loss was high in IR64, also after recovery. A qualitative comparison of these results with the ones of a similar experiment conducted in the field at the reproductive stage showed that only Apo, which also in this stage showed the highest antioxidant power, was able to maintain a stable grain yield under stress. Our results show that different metabolic and antioxidant adaptations confer drought tolerance to aerobic and upland rice varieties in the vegetative stage. The effectiveness of these adaptations differs between developmental stages. Unraveling the genetic control of these mechanisms might be exploited in breeding for new rice varieties adapted to water-limited environments.</p