Several species from the Brassica genus are very important agricultural crops in different parts of the world and are also known to be heavy metal accumulators. There have been a large number of studies regarding the tolerance, uptake and defense mechanism in several of these species, notably Brassica juncea and B. napus, against the stress induced by heavy metals. Numerous studies have also been published about the capacity of these species to be used for phytoremediation purposes but with mixed results. This review will focus on the latest developments in the study of the uptake capacity, oxidative damage and biochemical and physiological tolerance and defense mechanisms to heavy metal toxicity on six economically important species: B. juncea, B. napus, B. oleracea, B. carinata, B. rapa and B. nigra.

BackgroundUnderstanding the ecological consequences of roads and developing ways to mitigate their negative effects has become an important goal for many conservation biologists. Most mitigation measures are based on road mortality and barrier effects data. However, studying fine-scale individual spatial responses in roaded landscapes may help develop more cohesive road planning strategies for wildlife conservation.Methodology/Principal FindingsWe investigated how individuals respond in their spatial behavior toward a highway and its traffic intensity by radio-tracking two common species particularly vulnerable to road mortality (barn owl Tyto alba and stone marten Martes foina). We addressed the following questions: 1) how highways affected home-range location and size in the immediate vicinity of these structures, 2) which road-related features influenced habitat selection, 3) what was the role of different road-related features on movement properties, and 4) which characteristics were associated with crossing events and road-kills. The main findings were: 1) if there was available habitat, barn owls and stone martens may not avoid highways and may even include highways within their home-ranges; 2) both species avoided using areas near the highway when traffic was high, but tended to move toward the highway when streams were in close proximity and where verges offered suitable habitat; and 3) barn owls tended to cross above-grade highway sections while stone martens tended to avoid crossing at leveled highway sections.ConclusionsMortality may be the main road-mediated mechanism that affects barn owl and stone marten populations. Fine-scale movements strongly indicated that a decrease in road mortality risk can be realized by reducing sources of attraction, and by increasing road permeability through measures that promote safe crossings.

BackgroundDomestic cats ranging freely in natural areas are a conservation concern due to competition, predation, disease transmission or hybridization with wildcats. In order to improve our ability to design effective control policies, we investigate the factors affecting their numbers and space use in natural areas of continental Europe.Methodology/Principal FindingsWe describe the patterns of cat presence, abundance and space use and analyse the associated environmental and human constraints in a well-preserved Mediterranean natural area with small scattered local farms. We failed in detecting cats in areas away from human settlements (trapping effort above 4000 trap-nights), while we captured 30 individuals near inhabited farms. We identified 130 cats, all of them in farms still in use by people (30% of 128 farms). All cats were free-ranging and very wary of people. The main factor explaining the presence of cats was the presence of people, while the number of cats per farm was mostly affected by the occasional food provisioning with human refuse and the presence of people. The home ranges of eight radio tagged cats were centred at inhabited farms. Males went furthest away from the farms during the mating season (3.8 km on average, maximum 6.3 km), using inhabited farms as stepping-stones in their mating displacements (2.2 km of maximum inter-farm distance moved). In their daily movements, cats notably avoided entering in areas with high fox density.ConclusionsThe presence, abundance and space use of cats were heavily dependent on human settlements. Any strategy aiming at reducing their impact in areas of conservation concern should aim at the presence of settlements and their spatial spread and avoid any access to human refuse. The movements of domestic cats would be limited in areas with large patches of natural vegetation providing good conditions for other carnivore mammals such as red foxes.

a b s t r a c tSixteen wood mice Apodemus sylvaticus were radio-tracked in a Mediterranean cork oak agro-forestrysystem to describe their spatial distribution and organisation as well as their use of different habitat components. Our study, the first to analyse these features of wood mouse spatial ecology in Mediterranean agro-forestry environments using radio-tracking, showed a high variability in home ranges sizes reaching a mean values of 1.124 ± 0.925 ha (mean ± sd), with no inter-sexual differences (8 males and 8 females tracked in March and June 2008). The extent to which different habitat components were used by wood mice varied significantly (−N ln = 22.837, P < 0.0001, n = 6): while cork oak forests without understory were selected by both sexes equally in core areas (−N ln = 32.361, P < 0.0001, n = 6), we also found evidence for a female-driven selection for home ranges to be located in olive groves (−N ln = 59.949, P < 0.0001, n = 6), and movements to be set within cork oak forests with understory (−N ln = 15.091, P < 0.05, n = 6). This habitat preference appears to result from the need of females to ensure access to sufficient food resources, the need of males to ensure access to females, and the need of both sexes for cover protection from predators. Moreover, we also show that the use of arboreal strata, most probably to access food, may also be an important factor to consider in analysing habitat use by wood mice. Implications of the recent evolution of this agro-silvo-pastoral system to the species ecology are emphasized.

One of the most important structures for an individual's survival is a refuge, especially for species subject to significant predatory pressure or living in environments affected by severe climatic conditions. We studied how wood mice (Apodemus sylvaticus), inhabiting a Mediterranean environment, use nests and the factors that could be determining this use. Radiotracking of 16 mice allowed us to detect 24 diurnal nests, which were used with a high fidelity rate (1.75 nests/ animal). Nest sites that had been identified using radiotracking were matched with 24 randomly selected nonnest sites (located within an area defined by the sum of all individual home ranges), and all sites were characterized according to their macro-and micro-habitat parameters. Using a generalized linear model, we tested three hypotheses: (1) a nest's use is influenced by its proximity to food patches; (2) the degree of sheltering provided by each site influences its use; and (3) nest use is constrained by a combination of food-and shelterrelated features. Females had higher nest fidelity than males, and the degree of sheltering provided by each site had a positive significant influence on its use. Nests offering higher protection (e.g., under thick vegetation), good drainage (e.g., sleep slopes), and lower human and predatory disturbance (far from orchards) were most often used. The proximity to food patches seemed to negatively influence nest use. Results indicate the need to preserve patches of natural dense vegetation near riparian habitats, which is in agreement with the focus of mammalian protection plans in Mediterranean agricultural landscapes. These patches are important areas for Apodemus sylvaticus, an acorn disperser species, which is preyed on by raptors and mammalian carnivores.