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The human population dynamic in the North of Neuquén is characterized by well-documented seasonal transhumance movements, although the routes that connect lowland and upland areas as well as the factors influencing their selection remain largely unknown. In this study, we compare movement routes between lowlands and upland pastures in Tromen massif as described in interviews and participatory mapping with local herders with routes modelled by least cost paths (LCPs) on several cost surfaces based on Ensemble Distribution Modelling (EDM). Altitude and vegetation (cover and productivity) are two of the most important variables contributing to the potential for movement across the landscape. The LCPs calculated using the inverse of EDM surface – which mainly represents the contribution of altitude, distance to permanent rivers, and vegetation – display a good concordance with the ethnographic routes. Conversely, neither the LCPs estimated from a traditional multi-cost surface nor the LCPs based on each of three main variables separately predicted appropriately the location of the ethnographic routes. We showed that a modelling approach can contribute to a deeper understanding of the practice of transhumance in North Neuquén. [ABSTRACT FROM AUTHOR]

Following the Chernobyl accident in 1986, restrictions were placed on the movement and slaughter of sheep within upland areas of the UK because radiocaesium activity concentrations in their meat exceeded 1000Bqkg−1 fresh weight. Some farms remain under restriction in 2007. From 1991 to 1993 detailed studies were conducted on three sheep farms within the restricted area of west Cumbria to systematically assess the various parameters which may contribute to the observed variability in radiocaesium activity concentrations within sheep flocks. This paper reports the spatial variation in soil and vegetation activity concentrations across the grazed areas at these farms and determines the influence of grazing behaviour on variability in 137Cs activity concentrations between individual sheep within the flocks. Together with previously reported results, these new data are used to draw conclusions on the factors determining variability within the three flocks. However, the factors are too site specific to be able to generalise the findings to other farms within the restricted areas of the UK. [Copyright &y& Elsevier]

Abstract Seasonal cutting treatments were imposed on abandoned perennial ryegrass/white clover swards at three sites in the UK to determine the impact on species diversity and the contribution of different species to biomass. Before the cutting experiment, the abandoned swards had received no fertilizer applications and had been neither grazed nor cut for 3 years. The original sown species, Lolium perenne and Trifolium repens , had virtually disappeared during this period. Self-sown grasses, including Agrostis capillaris , Dactylis glomerata , Festuca rubra , Holcus mollis , Poa pratensis and P. trivialis , had become dominant at two sites. Ranunculus repens was the dominant species at the third site, and self-sown grasses, such as Holcus lanatus and P. trivialis , and Juncus and Carex species were also present. The standing herbage in 2·5 m × 2·5 m subplots was cut to 2·5 cm above ground level and removed annually in either June or October for 7 years at two sites and 6 years at the third site. Total biomass removed was generally < 4 t dry matter (DM) ha-1 , and both total and live biomass decreased over time in the June cutting treatment at two sites. There were large changes in species composition after initiating the two cutting treatments. The numbers of grass and dicot species increased, although many new species had a low frequency of occurrence. The contribution of species to biomass changed over time, with species showing a vegetative regenerative strategy decreasing over time at one site. At this site, annual cutting in June was slightly more effective than cutting in October in reducing the dominance of R. repens ; cutting in early October effectively reduced Juncus spp. At two sites, there was a decrease in the contribution of the species group showing seasonal regeneration by seed, and differences between cutting dates for two species within this group at one site. L. perenne and T. repens remained at much lower... [ABSTRACT FROM AUTHOR]