Search results for "Rif"
showing 10 items of 4029 documents
Elevated oxidative stress in pied flycatcher nestlings of eumelanic foster fathers under low rearing temperatures
2019
Striking variation in melanin coloration within natural populations is likely due to the different fitness outcomes of alternative phenotypes in varying environmental conditions. There are two types of melanin: eumelanins yield blackish hues, whereas pheomelanins yield reddish hues. The production of eumelanins requires low levels of glutathione (GSH), which is the most important intracellular antioxidant, whereas the production of pheomelanins requires high levels of GSH. We investigated the oxidative status of male pied flycatchers (Ficedula hypoleuca) with different degrees of melanin coloration under different temperatures during the nestling period. Moreover, we assessed the oxidative …
Avoiding perceived past resource use of potential competitors affects niche dynamics in a bird community
2014
Abstract. Background: Social information use is usually considered to lead to ecological convergence among involved con- or heterospecific individuals. However, recent results demonstrate that observers can also actively avoid behaving as those individuals being observed, leading to ecological divergence. This phenomenon has been little explored so far, yet it can have significant impact on resource use, realized niches and species co-existence. In particular, the time-scale and the ecological context over which such shifts can occur are unknown. We examined with a long-term (four years) field experiment whether experimentally manipulated, species-specific, nest-site feature preferences (sy…
Skylarks trade size and energy content in weed seeds to maximize total ingested lipid biomass
2014
International audience; tThe trade-off between forage quality and quantity has been particularly studied in herbivore organisms,but much less for seed eating animals, in particular seed-eating birds which constitute the bulk of win-tering passerines in European farmlands. The skylark is one of the commonest farmland birds in winter,mainly feeding on seeds. We focus on weed seeds for conservation and management purposes. Weedseeds form the bulk of the diet of skylarks during winter period, and although this is still a matter fordiscussion, weed seed predation by granivorous has been suggested as an alternative to herbicides usedto regulate weed populations in arable crops. Our objectives wer…
Phenotypic Divergence among West European Populations of Reed Bunting Emberiza schoeniclus: The Effects of Migratory and Foraging Behaviours
2013
[EN] Divergent selection and local adaptation are responsible for many phenotypic differences between populations, potentially leading to speciation through the evolution of reproductive barriers. Here we evaluated the morphometric divergence among west European populations of Reed Bunting in order to determine the extent of local adaptation relative to two important selection pressures often associated with speciation in birds: migration and diet. We show that, as expected by theory, migratory E. s. schoeniclus had longer and more pointed wings and a slightly smaller body mass than the resident subspecies, with the exception of E. s. lusitanica, which despite having rounder wings was the s…
Interbreeding between local and translocated populations of a cleaner fish in an experimental mesocosm predicts risk of disrupted local adaptation
2019
Source at https://doi.org/10.1002/ece3.5246. Translocation of organisms within or outside its native range carries the risk of modifying the community of the recipient ecosystems and induces gene flow between locally adapted populations or closely related species. In this study, we evaluated the genetic consequences of large‐scale translocation of cleaner wrasses that has become a common practice within the salmon aquaculture industry in northern Europe to combat sea lice infestation. A major concern with this practice is the potential for hybridization of escaped organisms with the local, recipient wrasse population, and thus potentially introduce exogenous alleles and breaking down coadap…
Mediterranean sponges from shallow subtidal rocky reefs: Cystoseira canopy vs barren grounds
2018
Abstract Porifera richness was investigated in Cystoseira canopies vs barren grounds considering different substrates at 6 areas in the Central-Western Mediterranean Sea. In total 31 sponge taxa were recorded at 2–7 m depth and the sponge community structure and composition were characterized by a notably low richness with 25 taxa in the Cystoseira forest and 15 in the barren area. As for the sponge habitus, the massive sponges were dominant in both facies, whereas encrusting, and cavity dwelling sponges were found in higher numbers in the Cystoseira forest. Results revealed that rocky substrata seem to play a key role in driving the sponge community composition and diversity in both facies…
Seed germination, salt stress tolerance and seedling growth of Opuntia ficus - indica (Cactaceae), invasive species in the Mediterranean Basin
2017
Abstract The present study, focuses on seed germination ecology and seedling growth of Opuntia ficus-indica (Cactaceae), a native species of arid and semi-arid regions of Mexico and invasive in the Mediterranean Basin. Shortly after collecting seeds in December 2014, scarification as well as the intra-specific variability in the responses of germination to light, temperature, salt stress and germination recovery were evaluated among three naturalized populations of this species in the Mediterranean. Moreover, seedling biomass production and the growth rate were measured. The most suitable method of scarification resulted the nail-clippers chipping. For all the populations, the germination t…
Agro-ecological benefits of faba bean for rainfed Mediterranean cropping systems
2017
This paper reviews the main results from a set of experiments carried out in a semiarid Mediterranean environment during the past 25 years on faba bean (<em>Vicia faba</em> L.), a crop traditionally grown in southern Italy and Sicily under rainfed conditions. These experiments focused on the residual effects of faba bean on subsequent crop(s) and assessment of the nitrogen (N) balance during the crop cycle, paying attention to both the environmental release of N (losses via volatilisation and denitrification) and estimates of N2 fixation as influenced by tillage system, intercropping, and presence/absence of mycorrhizal inoculum. Faba bean relied on N2 fixation more than other g…
Integrated Fixed Film Activated Sludge (IFAS) membrane BioReactor: The influence of the operational parameters
2020
Abstract The present paper investigated an Integrated Fixed Film Activated Sludge (IFAS) Membrane BioReactor (MBR) system monitored for 340 days. In particular, the short-term effects of some operational parameters variation was evaluated. Results showed a decrease of the removal rates under low C/N values. Respirometry results highlighted that activated sludge was more active in the organic carbon removal. Conversely, biofilm has a key role during nitrification. The major fouling mechanism was represented by the cake deposition (irreversible).
Plant species identities and fertilization influence on arbuscular mycorrhizal fungal colonisation and soil bacterial activities
2016
International audience; Plant species influence soil microbial communities, mainly through their functional traits. However, mechanisms underlying these effects are not well understood, and in particular how plant/ microorganism interactions are affected by plant identities and/or environmental conditions. Here, we performed a greenhouse experiment to assess the effects of three plant species on arbuscular mycorrhizal fungal (AMF) colonization, bacterial potential nitrification (PNA) and denitrification activities (PDA) through their functional traits related to nitrogen acquisition and turnover. Three species with contrasting functional traits and strategies (from exploitative to conservat…