Vole spatial distribution and dispersal in European organic and conventional farming systems

North European landscapes are highly dominated by agriculture, where small biotopes, e.g. meadows, uncultivated grassland, hedge rows, field boundaries, surroundings of water ponds, only comprise a low percentage. In recent years organic farming has expanded in acreage due to customers increased awareness regarding pesticide and fertilizer use and biodiversity conservation. However, organic farming has changed from an extensive production with small fields, low mechanical impact and high crop diversity towards larger fields, intensive mechanical treatment, lower weed densities and lower field diversity. Still, organic farms could play an important, role in the agricultural landscape as refuges for some small mammal species. We studied the responses of populations to habitat patches of different size and different surrounding management strategies (ecological and conventional farming). Studies were performed at two localities in Denmark, Kalø Estate in Eastern Jutland and the Bjerringbro area in Central Jutland. The sampling sites were represented by cultivated grassland habitat, small biotopes within cultivated fields and hedgerows between fields in rotation. Small mammal species assemblages were low in numbers in cultural farmland, and, on a property basis, not significantly different between organic and conventional farms. Very few species and individuals were present in the field matrix, and the small biotopes were by far the most important source of species richness. Species density was positively correlated with the size of the habitat, and, generally, more voles were found in organic habitat patches than in conventional ones. More field voles were found in organic grassland and more bank voles (Myodes glareolus) in organic hedge rows than in conventional ones. Telemetry studies of field voles showed low rates of dispersal and low colonization rates of the more or less isolated small biotopes at the time of year with no vegetation cover in the surrounding fields. We found no significant correlations between distance to nearest stepping stones/dispersal corridors and small mammal densities or species composition. In agricultural areas landscape structure influences the small mammal species living in this fragmented habitat matrix. The value of organic farms in respect to small mammal biodiversity depends mainly upon the number and area of small biotopes, and only to a minor degree upon the management of the fields. This is presumably related to a more dense and diverse vegetation cover, due to a lack of pesticide and fertilizer treatment in the organically managed small biotopes

Organic farms as refuges for small mammal biodiversity in agro ecosystems

Habitat fragmentation, the process by which relatively continuous habitats is broken into smaller pieces, occurs in natural systems but is to a high degree also human-induced through landscape use. Fragmentation of the landscape produces a series of habitat patches surrounded by a matrix of different habitats and land use regimes. The major landscape consequences of fragmentation are loss of habitat, reduction in habitat patch size, and increasing isolation of habitat patches. In general, population performance declines in response to habitat loss but size of remaining area and isolation effects is known also to influence the population trend. Small mammals are well suited for examination of population responses to habitat fragmentation as they have modest spatial requirements and short generation times. In theory, organic farms could play an important role in the agricultural landscape as refuges for some small mammal species, as the lack of pesticide and fertiliser treatment, less weed control, more diversified crop structure and a general environmental friendly attitude, form a basis for habitats that provide cover and food for small mammals, and thus for larger predators of these species. Furthermore, density and area of small biotopes could be expected to be higher in the organic farms, thus leading to a decreased distance between optimal habitats. This study compares species diversity and abundance of small mammals in conventional farms and intensively and extensively grown organic farms. In a wide range of different fields in conventional and organic farms, the diversity and density of small mammals were investigated by live-trapping sessions, comprising trap lines with 15 meters between each trap. We studied the responses of populations (belonging to 11 species of small mammals) to habitat patches of different size and different surrounding management strategies (ecological and conventional farming). We found a general correlation between the number of small mammal individuals and small biotope size. This correlation applies in autumn as well as in spring. There is only a weak tendency for more small mammals in small biotopes within organic farms compared within conventional farms. The number of small mammal species stabilises at small biotope sizes around 1000 square meters. The value of organic farms in respect to small mammal biodiversity depends mainly upon the number and area of small biotopes, and only to a minor degree upon the treatments of the fields

ORGANIC FARMS AS REFUGES FOR SMALL MAMMAL BIODIVERSITY

Habitat fragmentation, the process by which relatively continuous habitats is broken into smaller pieces, occurs in natural systems but is to a high degree also human- induced through landscape use. Fragmentation of the landscape produces a series of habitat patches surrounded by a matrix of different habitats and/or land use regimes. The major landscape consequences of fragmentation are loss of habitat, reduction in habitat patch size, and increasing isolation of habitat patches. In general, population performance declines in response to habitat loss but size of remaining area and isolation effects is known also to influence the population trend. Small mammals are well suited for examination of population responses to habitat fragmentation as they have modest spatial requirements and short generation times. In theory, organic farms could play an important role in the agricultural landscape as refuges for some small mammal species, as the lack of pesticide and fertiliser treatment, less weed control, more diversified crop structure and a general environmentalfriendly attitude, form a basis for habitats that provide cover and food for small mammals, and thus for larger predators of these species. Furthermore, density and area of small biotopes could be expected to be higher in the organic farms, thus leading to a decreased distance between optimal habitats

Lancering af Supercykelstier

Begrebet Supercykelstier er velkendt i det meste af landet. I flere større byer bliver der anlagt cykelstier, der adskiller sig fra de normale cykelstier ved at være et niveau bedre, have større komfort og bedre fremkommelighed. Der er services, som gør den daglige pendlertur nemmere, tryggere og mere behagelig. I foråret 2017 sker der noget nyt på Supercykelstiområdet. Supercykelstisamarbejdet åbner yderligere fem Supercykelstier og sammen med de allerede eksisterende tre Supercykelstier, får hovedstadsregionen nu et sammenhængende net af Supercykelstier som de første i Danmark. Det skal markeres! Derfor lancerer Region Hovedstaden og de 13 deltagende kommuner en indsats for dels at synliggøre nettets eksistens, dels for at motivere flere pendlere på de middellange distancer (5-20 km) til at hoppe på cyklen og gøre brug af supercykelstierne.Som en del af ovenstående indleder Regionen og kommunerne et samarbejde med flere af de virksomheder, der ligger tæt på ruterne, med det formål at få flere medarbejdere til at tage cyklen til og fra arbejde - til fordel for både virksomhederne, pendlerne og samfundsøkonomien. Dette indlæg vil på baggrund af vedhæftede koncept gennemgå resultaterne fra lanceringen af Supercykelstier i foråret 2017 med særligt fokus på samarbejdet med virksomheder og med fokus på bred kommunikation af lanceringen af Supercykelstier

Three questions to the human brain

An approximately 20% increase in cerebral blood flow (CBF) and the cerebral metabolic rate for oxygen manifest during whole body exercise with determination of brain tissue flow and arterial inflow to the brain. Yet, during intense exercise CBF approaches the resting level in response to the decrease in arterial carbon dioxide tension with the exponential increase in ventilation. Here it is illustrated that the increase in CBF during exercise appears to depend to the ability to raise cardiac output and it is speculated whether there is a sympathetic restrain on CBF when the increase in cardiac output is small. Furthermore, it is considered whether the restrain in CBF during intense exercise affects cerebral oxygenation to an extent that it provokes so-called central fatigue. Finally it is highlighted that the cerebral activation associated with exercise provokes uptake of carbohydrate, notably of lactate, that cannot be accounted for by the concomitant increase in the cerebral metabolic rate for oxygen and it is pointed out that it remains unknown why that apparently surplus carbohydrate uptake by the brain is in need

Wildlife friendly agriculture: which factors do really matter? A genetic study on field vole

The distribution of genetic differentiation and the directions of gene flow were determined mainly by landscape factors: thus the expectation that organic fields act as genetic reservoir was not met. The fact that agricultural area presented more sub-populations than the undisturbed one, together with the importance of connectivity and habitat size in shaping gene flow and genetic differentiation, shows that switching to organic farming might not be enough to ensure the conservation of species in the agricultural environment. These results emphasise the need to include landscape structure in management policies