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5 Uppsatser om Ditching - Sida 1 av 1
Artrika vägkanter - hur påverkas de av slåtter och underhållsdikning?
ABSTRACT
This study is an exam work at the Department of Ecology at the Swedish Agricultural University, Ultuna, Uppsala. The field work was performed in the counties of Uppsala and Västmanland.
Grassland areas, exposed to annual mowing, are known to host a variety of rare and red-listed vascular species. The area of these grassland are, however, decreasing in the landscape due to modern farming. The fact that roadside verges maintain regular mowing has proven to be a successful concept for many rare vascular plant species in this habitat.
Vascular plants along roadside verges at the State road network were inventoried due to a government mandate during 1995 and 1996. As a result ?Species rich roadsides? were pointed out.
Metod för inventering av underhållsbehov för skogsdiken
Large areas have been ditched in Sweden during the past 100 years to improve the forest production. Ditching and also maintenance of old ditches are operations having mainly negative effects on water quality, flora and fauna and changing characteristics of soil. The purpose of this study was to suggest a method for inventory of the need for Ditching maintenance in old forest ditches that takes biodiversity, water protection and forest production into consideration. Inventory methods from five Swedish and Finnish forest companies, agencies and organisations were compared. Their employees were interviewed about their handling with ditches, forest production and nature conservation.
Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)
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..
Vattenkvalitén i Fredstorpsbäcken - dikad bäck på fastigheten Rämningstorp i Skara kommun :
The estate of Rämningstorp in the region of Västergötland in southern Sweden is administered by the holding trust company Skogssällskapet i Skövde. In 1999 measures were taken by Skogssällskapet to drain the stream Fredstorpsbäcken as a means to increase the forest productivity of the surrounding lands, which are situated on the estate of Rämningstorp. Almost immediately after the drainage, the streamwater turned turbid and a landowner downstream reported the issue to the county administrative board of the region.
The aim of this thesis was firstly to analyse the suspended matter that appeared during summer/autumn and secondly to explain why it came to be. Initial hypotheses for the explanation to the greyish turbid water were that it was either 1) a chemical/biochemical precipitate, or 2) an bacterial/algal blooming.
Vattensänkningar : en analys av orsaker och effekter
There are records of lowering of the water level in a lot of the Swedish lakes from the middleof the 1700th century. The aim was gaining more areable land to meet the needs of more foodto support the expanding population. In areas with top soil which contents of clay or loam asin the southwest of Scania in southern Sweden this was proven to be a successful wayexpanding the total outcome of the harvest.The studied area in the northeast of Scania, though, consists of morain with a lot of mires -much less nutritious conditions. When the water level is lowered the atmosphere gets accessto the peat. The dissolving of the organic matter that has been suppressed by the lack ofoxygene below water level continues.