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Carry-over effects take place when events occurring in one season influence individual performance in a subsequent season. Blood parasites (e.g. Plasmodium and Haemoproteus) have strong negative effects on the body condition of their hosts and could slow the rate of feather growth on the wintering grounds. In turn, these winter moult costs could reduce reproductive success in the following breedin

Background: The major histocompatibility complex (MHC) is an important component of the vertebrate immune system and is frequently used to characterise adaptive variation in wild populations due to its co-evolution with pathogens. Passerine birds have an exceptionally diverse MHC with multiple gene copies and large numbers of alleles compared to other avian taxa. The Nesospiza bunting species comp

In the present study, we aim at relating Forbes' remarkable paper on "The lake as a microcosm", published 125 years ago, to the present status of knowledge in our own research group. Hence, we relate the observations Forbes made to our own microcosm, Lake Krankesjon in southern Sweden, that has been intensively studied by several research groups for more than three decades. Specifically, we focus

BACKGROUND: Patterns of spatial variation in discrete phenotypic traits can be used to draw inferences about the adaptive significance of traits and evolutionary processes, especially when compared to patterns of neutral genetic variation. Population divergence in adaptive traits such as color morphs can be influenced by both local ecology and stochastic factors such as genetic drift or founder ev

There is growing interest in the use of arbuscular mycorrhizal fungi (AMF) for ecological restoration. Numerous commercial AMF products are now available and are often used in preference to collecting indigenous AMF in treating restoration plants. Commercial AMF products are typically based on AMF strains exotic to the plant species and locations where they are used. We treated rooted cuttings of

Pollination contributes to an estimated one third of global food production, through both the improvement of the yield and the quality of crops. Volatile compounds emitted by crop flowers mediate plant-pollinator interactions, but differences between crop varieties are still little explored. We investigated whether the visitation of crop flowers is determined by variety-specific flower volatiles u

This paper investigates the interactive relationships among China energy price shocks, stock market, and themacroeconomy using multivariate vector autoregression.The results indicate that there is a long cointegration among them. A 1% rise in the energy price index can depress the stock market index by 0.54% and the industrial value-adding growth by 0.037%. Energy price shocks also cause inflation

Nannandry is a sexual system where males ("dwarf males") are much smaller than the conspecific females. Dwarf males occur in a wide range of unrelated organisms but the evolutionary advantages of this condition are poorly understood. The dwarf male sexual system results in differences in the mode of dispersal and establishment as well as the life span between males and females. Such differences mu

The critical levels for ozone effects on vegetation have been reviewed and revised by the LRTAP Convention. Eight new or revised critical levels based on the accumulated stomatal flux of ozone (POD gamma, the Phytotoxic Ozone Dose above a threshold flux of Y nmol m(-2) PLA s(-1), where PLA is the projected leaf area) have been agreed. For each receptor, data were combined from experiments conducte

We tested the habitat filtering hypothesis by measuring the phylogenetic structure in marine bacterial communities before and after experimentally induced stress. The habitat filtering hypothesis predicts that phylogenetic clustering (mean relatedness) should increase as the environment becomes suitable for only a subset of the original community. We show that community composition and phylogeneti

Computer vision applications are very useful to study animal movements, but due to their intrinsic complexity they are challenging to design, implement, and use properly. We here describe a calibration procedure for a laboratory stereo vision system for tracking zooplankton in three dimensions (3D). We demonstrate the crucial importance of using a correct calibration for proper interpretation of a

Aims Vegetation stimulates, in general, soil mineral weathering. It has been hypothesized that plant-associated microorganisms, especially ectomycorrhizal fungi play a major role in this process. We studied apatite dissolution in a vegetation gradient in southern Norway to test the role of ectomycorrhizal vegetation on mineral weathering. Methods A natural occurring lead contamination, probably pr

Calcicole plant species are vulnerable to acidification and fertilization, caused by deposition and changes in land use, since they are adapted to nutrient-poor calcareous conditions. In this study we used vegetation data (vascular plants, bryophytes and lichens) from 1964 and 1985 and stored soil samples from 1966 to investigate long-term soil chemistry and vegetation changes in a semi-natural, s

Biochar application to soils has potential to simultaneously improve soil fertility and store carbon to aid climate change mitigation. While many studies have shown positive effects on plant yields, much less is known about the synergies between biochar and plant growth promoting microbes, such as mycorrhizal fungi. We present the first evidence that arbuscular mycorrhizal (AM) fungi can use bioch

The activity of saprotrophic fungi and bacteria, and the balance between them, can affect decomposition. Arbuscular mycorrhizal (AM) fungi are also important for the nutrient and energy transfer in soil. Microbial community composition and activity are believed to have seasonal patterns, and are known to be highly influenced by environmental factors such as pH and nutrient conditions. To evaluate

Political institutions are keen to use the best available scientific knowledge in decision-making. For environmental policy, relevant scientific evidence can be complex and extensive, so expert judgment is frequently relied upon, without clear links to the evidence itself. We propose a new transparent process for incorporating research evidence into policy decisions, involving independent synopsis

Large plants are often more conspicuous and more attractive for associated animals than small plants, e.g. due to their wider range of resources. Therefore, plant size can positively affect species richness of associated animals, as shown for single groups of herbivores, but studies usually consider intraspecific size differences of plants in unstandardised environments. As comprehensive tests of

The integrated model WORLD and Hubbert's model were used for assessment of future supply for different metals: iron, nickel, manganese, chromium, molybdenum, tantalum, niobium, rhenium, zir- conium, tungsten, cobalt, copper, zinc, lead, aluminium and the technology metals derived from copper ezinc mining (tellurium, selenium, gallium, indium, antimony, bismuth, tin, germanium, selenium). The conne

Mate choice for major histocompatibility complex (MHC) compatibility has been found in several taxa, although rarely in birds. MHC is a crucial component in adaptive immunity and by choosing an MHC-dissimilar partner, heterozygosity and potentially broad pathogen resistance is maximized in the offspring. The MHC genotype influences odour cues and preferences in mammals and fish and hence olfactory