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Understanding limiting factors and interspecific interactions is fundamental to wildlife management and can be inferred from multiscale patterns of resource selection. We studied winter resource selection and overlap of white-tailed deer (Odocoileus virginianus) and translocated female elk (Cervus elaphus) over 2 winters in central Ontario, Canada. Microhabitat data were collected along 4 organism-centered spatial scales: site, trail, feeding station, and diet. Although winter conditions varied between years, white-tailed deer consistently traveled and fed in habitats with greater coniferous basal area than elk. Neither species demonstrated selection for coniferous basal area or snow depth across scales. At successively...
A new transportation demand model is described showing a simple data-base structure. It only requires input data referring to the fleets and the engine characteristics of the transportation park. The main characteristic of the model is its expertise in analysing the effects of different policies oriented to the reduction of the pollution levels and to the energy savings in the transportation sector. The results are provided both in terms of energy consumption and quantities of pollutant released to the environment. The effects of different transportation scenarios can be easily analysed using a simple "electronic sheet" way of representation.
We have conducted a detailed analysis of costs associated with today’s technology for CO2 separation and capture at three types of power plants: integrated coal gasification combined cycles (IGCC), pulverized coal-fired simple cycles (PC), and natural gas-fired combined cycles (NGCC). The analysis was based on studies from the literature that analyzed the economics of capturing CO2 emitted at power plants. In this paper, we present a composite cost model and perform a sensitivity analysis to identify the cost-drivers for capture. We conclude that with new developments, CO2 capture and sequestration can become a cost-effective mitigation pathway.
We have conducted a detailed analysis of costs associated with today’s technology for CO2 separation and capture at three types of power plants: integrated coal gasification combined cycles (IGCC), pulverized coal-fired simple cycles (PC), and natural gas-fired combined cycles (NGCC). The analysis was based on studies from the literature that analyzed the economics of capturing CO2 emitted at power plants. In this paper, we present a composite cost model and perform a sensitivity analysis to identify the cost-drivers for capture. We conclude that with new developments, CO2 capture and sequestration can become a cost-effective mitigation pathway.
Reciprocal selection pressures often lead to close and adaptive matching of traits in coevolved species. A failure of one species to match the evolutionary trajectories of another is often attributed to evolutionary lags or to differing selection pressures across a geographic mosaic. Here we show that mismatches in adaptation of interacting species–an obligate brood parasitic duck and each of its two main hosts–are best explained by the evolutionary dynamics within the host species. Rejection of the brood parasite's eggs was common by both hosts, despite a lack of detectable cost of parasitism to the hosts. Egg rejection markedly reduced parasite fitness, but egg mimicry experiments revealed no phenotypic natural...
A new transportation demand model is described showing a simple data-base structure. It only requires input data referring to the fleets and the engine characteristics of the transportation park. The main characteristic of the model is its expertise in analysing the effects of different policies oriented to the reduction of the pollution levels and to the energy savings in the transportation sector. The results are provided both in terms of energy consumption and quantities of pollutant released to the environment. The effects of different transportation scenarios can be easily analysed using a simple "electronic sheet" way of representation.
Abstract (from http://rspb.royalsocietypublishing.org/content/282/1799/20142454): Hybridization between native and non-native species has serious biological consequences, but our understanding of how dispersal and selection interact to influence invasive hybridization is limited. Here, we document the spread of genetic introgression between a native ( Oncorhynchus clarkii) and invasive ( Oncorhynchus mykiss) trout, and identify the mechanisms influencing genetic admixture. In two populations inhabiting contrasting environments, non-native admixture increased rapidly from 1984 to 2007 and was driven by surprisingly consistent processes. Individual admixture was related to two phenotypic traits associated with fitness:...
This paper analyzes the determinants and barriers of energy conservation investment behaviour. A number of barriers were found in a literature survey. A three-phase investment model on the micro level was constructed. Hypotheses derived from the model were empirically tested by analyzing a survey of more than 300 Dutch Firms. Economic variables seem to determine investment behaviour to a large extent.
Eight major industrial processes areresponsible for over 50% of industrial energy consumption in most countries. The energy efficiency of these processes was determined in a number of countries, with appropriate corrections for structural differences between countries. It is shown that considerable differences occur between countries, but that manufacturing industry in Eastern Europe in general is less efficient than in EU countries. In all cases efficiency is worse than what is technically and economically feasible. International comparisons provide information on energy efficiency differences, insight into technological differences between countries and into costs requirements for efficiency improvements. The...
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Bromus tectorum (cheatgrass or downy brome) is an exotic annual weed that is abundant in western USA. We examined variation in six microsatellite loci for 17 populations representing a range of habitats in Utah, Idaho, Nevada and Colorado (USA) and then intensively sampled four representative populations, for a total sample size of approximately 1000 individuals. All loci were homozygous, indicating that the species is strongly selfing. Populations consisted of a few common genotypes and variable numbers of rare genotypes. Small sample sizes (n = 10 individuals) were adequate for distinguishing among populations, but larger sample sizes were needed to characterize more diverse populations, particularly in terms...
Current climate models predict a shift to warmer, drier conditions in the southwestern US. While major shifts in plant distribution are expected to follow these climate changes, interactions among species and intraspecific genetic variation rarely have been incorporated into models of future plant distributions. We examined the drought-related mortality of pinyon pine (Pinus edulis) in northern Arizona focusing on trees that showed genetically-based resistance or susceptibility to a nonlethal herbivore, the shoot-boring moth, Dioryctria albovittella. Because moth resistant trees have outperformed susceptible trees during 20 years of study, and herbivory has been shown to increase drought related mortality, we expected...


    map background search result map search result map Ecological significance of microsatellite variation in western North American populations of Bromus tectorum Ecological significance of microsatellite variation in western North American populations of Bromus tectorum