The forestry is the main use of forests in Sweden which results in a number of positive aspects but also a number of negative effects on our nature. Aquatic ecosystems are specifically exposed to land use by the forest industry. The problem areas that arise are mainly discharge of nutrients, mercury, change in hydromorphology and local environment, sludge transport, absence of dead wood in streams and altered solar radiation. In order to reduce negative impact and protect natural populations of species but also to protect important ecosystems, there are a number of national prospective objectives and laws. From the year 2014, a number of prospective aims have been introduced to get a common view of the problem factors, but also to get a common representation of how the forestry measures should be carried out. This work evaluated the width of the riparian buffer zone left along the 138 streams at final clearcutting in the Vindelälven catchment, comparing three periods: period 1 (year 2001-2007), period 2 (year 2008-2013) and period 3 (year 2014-2018). The work also included a count of the number of dead wood objects that occur in 16 of the 138 streams in the study area. The method of the study is based on remote sensing using ArcGIS software, along with a field inventory to verify the remote sensing with reality. The results found from the study were that a significant increase in average minimum-width was shown between periods 1 and 3 (ANOVA, n = 138, df = 2, F = 5.083 and p = 0.007). The results from the average width were not significantly different but suggest a positive correlation between lower age of final clearcutting and the average width of the riparian zone. The density of dead wood in the streams of the study site did not give any significant differences or correlations depending on time period. What could be explained from the result was that the presence of beaver (Castor fiber) positively affected the amount of dead wood. To conclude, positive effects of the introduction of new objectives for riparian buffer zone management were indicated. This is a sign that the forestry industry is moving towards implementing more sustainable methods. In addition, a method based on remote sensing for measuring riparian buffer zone widths was found to provide reliable estimates in the Vindelälven catchment, Västerbotten County. / Grip on Life IP
| Identifer | oai:union.ndltd.org:UPSALLA1/oai:DiVA.org:umu-161041 |
| Date | January 2019 |
| Creators | Samuelsson, Valdemar |
| Publisher | Umeå universitet, Institutionen för ekologi, miljö och geovetenskap |
| Source Sets | DiVA Archive at Upsalla University |
| Language | Swedish |
| Detected Language | English |
| Type | Student thesis, info:eu-repo/semantics/bachelorThesis, text |
| Format | application/pdf |
| Rights | info:eu-repo/semantics/openAccess |
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