63 uppsatser · sida 1 av 5
… ecological importance and increase the anthropogenic negative impacts on these species. Because of technical and environmental reasons (nutrient leakage, erosion) guidelines for stump harvesting recommend to retain stumps standing in wet parts of clear cuts. However, stumps in …
does the area affect species number and composition?
Sand pits are a valuable habitat which can hold many sand living species including several endangered ones. As many sand habitats with exposed sand are declining, sand pits have a potential as a substitute habitat. This study was conducted to see what effect the area of a sand …
In a city sometimes conflicts arise between either to save the species-rich vacant lots where many species thrive, or to build new buildings. Green roofs can then serve as a refuge for plants and animals that have had their natural habitat destroyed or diminished. Today we know …
En jämförande studie från dal till topp i ett nordligt och sydligt svenskt fjäll
… birds in the Swedish mountain area. Three questions were asked: 1) Which bird species can be found during the breeding season along a low mountain slope from a forested valley to a mountaintop with bare mountain environment? 2) Do the number of species and individuals differ in …
… limestone forest on Seram Island in respect to (1) forest structure, (2) tree species richness and (3) tree species composition. We set up 5 plots, each of 0.2 ha, at one site, Mawalai, and collected data on tree variables (tree diameter ?10 cm) as well as for some other life …
The species in the genus bumblebees (Bombus) are important pollinators. In the world there are 250 bumblebee species and there are 34 species in Norway. The purpose of this study is 1) to assess changes in the species composition of bumblebees in twenty different places in …
… a timber shortage in Sweden and a large scale introduction of the exotic tree species lodgepole pine started. An introduction of a foreign tree species means a risk of a negative influence on the forests ecosystem. Today, the stands that were established in the 70?s are …
Changes in the vegetation composition after a wetlandrestoration
… be found in the wetlands and it is one of the habitats where most different species exist. In the 17th Century people started to ditch damp environments, such as bogs, to create a productive cultivated ground. Further ditches were made when the forestry gave large economical …
Hur viltvård kan påverka variationen av lövträd och buskar
… fragmentation and reduction of deciduous forests in Sweden is threatening many species. Particularity worrying is the loss of broad-leaf trees, since a diversity of species is often associated to them. Today many deciduous trees are situated along the border between forested and …
… has always influenced the surrounding areas, the forest as well. Structure and species composition have changed during human land use. Knowledge regarding these changes should be of great interest for conservation and forestry. We have analyzed human impact on the tree species …
… the study aimed to qualify the effect of wild boar rooting on cover ratio, species richness and species composition in a temperate deciduous forest. The rooting frequency did increase from 0% in 2010 to 61% in 2013. The results indicated a general cover loss of both spring …
… for macrophytes are based on the total phosphorus preference of the respective species. The focus is thus mainly on the nutrient level of the investigated lakes and the environmental problem monitored is eutrophication. Macrophytes are one of the five biological quality factors …
Carabidae) i hävdade strandnära gräsmarker :
… different management regimes, either late or continous grazing, or meadow. The species composition was analysed by ordination analyses, i.e. DCA and CCA. Diversity was calculated both as species richness and as the Shannon diversity index. Most differences were found between the …
… Research for Northern Sweden. The aim of the study was to determine how plant species richness and diversity influence the nitrogen pools and nitrogen fluxes in the soil. Plant and soil samples from a biodiversity experiment in grasslands were used. Thirty plots with 12 …
… of vascular plants, amount of dead wood and the abundance of signal-species were measured and registered. The species composition and especially the composition of tree species, differed between forests with different exposition and different historical use. Abundance and …
