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Forest ecological studies on drained peat land in the province of Uppland, Sweden : Skogsekologiska studier på dikad torvmark i Uppland /Holmen, Hilmar, January 1964 (has links) (PDF)
Diss. Uppsala : Univ.
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Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)Miekk-oja, Olli January 2013 (has links)
Peat lands are a great potential resource for increased forest growth in Sweden, there are approximately 6.5 million hectares of peat lands, whereof around 70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste land. There are over 200 000 hectares of peat land that is already drained and wooded, and that may be suitable for fertilization. Forest production on peat soils usually requires drainage and fertilization. Dewatering requires ditching the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The purpose of this work was to examine the effects of potassium fertilization on the growth of spruces that were planted on drained peat land and how different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance transport in the tree. Potassium is also important for the carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter resistance of many species. Potassium is not found in any organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was left without fertilization. All plots that were fertilized with potassium grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality estimation of wetlands after ditching (dikningsbonitering). The plot with most potassium produced after fertilizationaproximately in level with theoretical estimations. Key words: Peat land, Fertilization, Ditching, Growth, site quality.
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How does drainage affect hydrology and hydrochemistry in boreal peatlands?Enetjärn, Albin January 2018 (has links)
Boreal peatlands are substantial terrestrial carbon storages. They are also important for the function of several large-scale cycles and systems that humanity benefits from. Drainage affects peatlands by establishing a new, lower equilibrium for the groundwater table. As a consequence of a lowered groundwater table and physical disturbance from the ditch, a chain of events is triggered, causing a number of changes in the hydrology and hydrochemistry of peatlands. The review aimed at gathering the most relevant literature on how boreal peatlands are affected by drainage. This was carried out by searching for scientific articles on online databases and libraries. Besides reviewing hydrology and hydrochemistry, a compilation of boreal peatland characteristics and a background on the history of Swedish peatland drainage are handled in the report. The results show that concentrations and loads for a long range of water quality parameters are affected by drainage. The effects vary a lot depending on different peatland characteristics. Both runoff and chemical changes depends largely on whether ditches reach mineral soil beneath the peat. The most obvious and adverse effect on chemistry is a large increase in suspended solid concentration and export. Other changes include increases of mineralized nitrogen, decreased organic carbon transport, increased annual runoff and increased levels for a number of elements, such as Mg, Ca, K and Mn.
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