Vnitřní periferie v České republice jako mechanismus sociální exkluze

Peripheral regions are most often described in terms of economic geography. However, this study stresses more the sociological aspects of peripheries, studying not only the causes, but also the social effects of life in peripheral regions. The authors use the term ‘inner peripheries’ because most of the peripheral regions detected in their analyses are located in the inner parts of the country, mainly along the borders of the administrative regions (kraje). Their approach combines the concept of the life world (espace vécu) as defined by A. Frémont and A. Giddens when describing the social and cultural consequences of living in peripheries, and a modified version of G. Myrdal´s theory of cumulative circular causation when trying to explain the origin and growth of peripheries. In the Czech Republic inner peripheries are usually the peripheral zones of metropolitan areas and regional centre areas. In the mid-1990s population numbers stopped declining in some peripheries as a result of suburbanisation processes, but in other peripheries depopulation processes continued. This last category of inner peripheries can be described as the hard core of Czech peripheral regions and in the authors’ opinion they warrant the development of specifi c regional policy measures, stressing the creation of new jobs, the improvement of public transport, greater accessibility of service centres, and co-operation among communities

Native drivers of fish life history traits are lost during the invasion process

Rapid adaptation to global change can counter vulnerability of species to population declines and extinction. Theoretically, under such circumstances both genetic variation and phenotypic plasticity can maintain population fitness, but empirical support for this is currently limited. Here, we aim to characterize the role of environmental and genetic diversity, and their prior evolutionary history (via haplogroup profiles) in shaping patterns of life history traits during biological invasion. Data were derived from both genetic and life history traits including a morphological analysis of 29 native and invasive populations of topmouth gudgeon Pseudorasbora parva coupled with climatic variables from each location. General additive models were constructed to explain distribution of somatic growth rate (SGR) data across native and invasive ranges, with model selection performed using Akaike's information criteria. Genetic and environmental drivers that structured the life history of populations in their native range were less influential in their invasive populations. For some vertebrates at least, fitness-related trait shifts do not seem to be dependent on the level of genetic diversity or haplogroup makeup of the initial introduced propagule, nor of the availability of local environmental conditions being similar to those experienced in their native range. As long as local conditions are not beyond the species physiological threshold, its local establishment and invasive potential are likely to be determined by local drivers, such as density-dependent effects linked to resource availability or to local biotic resistance

Native drivers of fish life history traits are lost during the invasion process

Rapid adaptation to global change can counter vulnerability of species to population declines and extinction. Theoretically, under such circumstances both genetic variation and phenotypic plasticity can maintain population fitness, but empirical support for this is currently limited. Here, we aim to characterize the role of environmental and genetic diversity, and their prior evolutionary history (via haplogroup profiles) in shaping patterns of life history traits during biological invasion. Data were derived from both genetic and life history traits including a morphological analysis of 29 native and invasive populations of topmouth gudgeon Pseudorasbora parva coupled with climatic variables from each location. General additive models were constructed to explain distribution of somatic growth rate (SGR) data across native and invasive ranges, with model selection performed using Akaike's information criteria. Genetic and environmental drivers that structured the life history of populations in their native range were less influential in their invasive populations. For some vertebrates at least, fitness-related trait shifts do not seem to be dependent on the level of genetic diversity or haplogroup makeup of the initial introduced propagule, nor of the availability of local environmental conditions being similar to those experienced in their native range. As long as local conditions are not beyond the species physiological threshold, its local establishment and invasive potential are likely to be determined by local drivers, such as density-dependent effects linked to resource availability or to local biotic resistance