Search for dissertations about: "Biologiska effekter"

Showing result 1 - 5 of 138 swedish dissertations containing the words Biologiska effekter.

2. 1. Remote sensing of grassland communities : integrated effects of soil nutrients and habitat age

   Author : Oskar Löfgren; Biodiversitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Remote sensing; Plant ecology; semi-natural grassland; Nitrogen; Phosphorus; Semi-natural grassland; Plant ecology; Remote sensing; Nitrogen; Phosphorus; Spectral reflectance; grassland specialists; Succession;

   Abstract : Semi-natural grasslands are characterized by high fine-scale plant species richness. The richest grassland communities, with many habitat-specialist species, are found in ancient grassland sites that have a long continuity of grazing management and low levels of soil nutrients. Grazed grasslands were widespread in the historical landscape. READ MORE

4. 2. Effects of created habitats on farmland biodiversity

   Author : Annelie Jönsson; Biodiversitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; agricultural intensification; brown hare; common pheasant; farming intensity; granivorous passerines; grey partridge; habitat creation; landscape heterogeneity; pollinators;

   Abstract : Agricultural intensification has caused severe declines among biodiversity in European farmland over the last half century. The transformation of the agricultural landscape has led to reduced availability of key resources such as food, nesting habitat and shelter. READ MORE

5. 3. Effects of farmland heterogeneity at multiple spatial and temporal scales on house sparrow (Passer domesticus) population ecology

   Author : Maria von Post; Biodiversitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Farmland heterogeneity; house sparrow; agricultural intensification; farm specialisation; landscape complementation; resource separation; population limitation;

   Abstract : Strong declines of European farmland birds in recent decades are assumed to be caused by decreased food availability resulting from agricultural intensification and concomitant loss of farmland heterogeneity. One of the species suffering particularly strong declines in NW European countries is the house sparrow. READ MORE

6. 4. Biodiversity in Agricultural Landscapes: Landscape and Scale-Dependent Effects of Organic Farming

   Author : Maj Rundlöf; Biodiversitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Djurekologi; Natural science; Naturvetenskap; Ekologi; Animal ecology; plants; spatial scales; species richness; Ecology; landscape ecology; agri-environment schemes; farming practice; conservation; butterflies; bumble bees;

   Abstract : Declines in the distribution and abundance of many farmland species during recent decades have been attributed to agricultural intensification. Agri-environment schemes are commonly used in Europe to reduce this loss of farmland biodiversity, but their effectiveness may depend on several external factors. READ MORE

7. 5. The threat from non indigenous species - ecosystem vulnerability, global distribution and co-occurrence with other major threats

   Author : Helena Berglund; Biodiversitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; threats; distribution range; isolation; endemism; invasions; invaders; vulnerability; non indigenous species; rarity; threatened species;

   Abstract : We live in a globalised world where people and goods travel large distances. Various species are brought along on these journeys, intentionally or as hitchhikers. Some of these species establish populations in regions to which they could not have spread without human assistance, and where they are considered to be non indigenous species (NIS). READ MORE