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766 Uppsatser om Soil conservation - Sida 44 av 52

Mångbruksplan Äspinge 2:2

This plan of multiple-use is made on the private owned forestproperty Äspinge 2:2 in the middle of Skåne. The term ?multiple-use? came to Sweden in the beginning of the twentieth century and has slowly grown until about 30 years ago when the laws of nature conservation and sustainability was written into the forest law. The so called ecoturism got more and more popular and people began to seek space and silence in difference to the life in the highly populated areas. This also encouraged foreign tourists to come to Sweden. Mostly danish, german, and dutch people.

Det blåser kring vindkraft! : En kontroversstudie om vindkraftsetablering på Västkusten

Vårt syfte med denna studie är att undersöka de kontroverser som uppstått vid vindkraftsetableringar på Västkusten. Detta syfte innefattar frågeställningar om vilka argument och aktörer som är inblandade och vad som formar en aktörs åsikter.Anledningen till att vi valde detta område var på grund av ett förslag vi fick från en konsult inom området. När vi studerat ämnet närmare insåg vi att det existerar kontroverser kring de olika etableringar som skett och även runt de som endast är i planeringsstadiet. Dessutom insåg vi att det inte fanns mycket aktuell forskning inom området.Studien är baserad på material som har insamlats i form av samrådsredogörelser, artiklar, insändare och fyra utförda intervjuer. Tolkning av materialet har skett utifrån en diskursanalys som gett resultat i form av tre olika diskurser inom kontroversen; Miljödiskursen, Lekmannadiskursen och den Ekonomiska diskursen.

Survey of Fusarium species on yellow onion (Allium cepa) on Öland

It has been observed by both onion producers and a plant protection advisor on Öland (an island off the east coast of Sweden) that basal rot is the largest contributory factor to reduced onion quality and yield. Basal rot is mainly caused by species of Fusarium fungi. The aim of this study was to: a) investigate which species of Fusarium that can be found in onion produced on Öland, b) describe the symptoms caused by the different Fusarium fungi found and c) explore, through interviews with the onion producers on Öland, the mechanisms that may be involved in the observed increase in basal rot.Onion bulbs (Allium cepa) were sampled on two occasions. In total 181 onions from 11 different fields were analysed. In addition, eight onion producers were interviewed.

Naturreservat : en bra naturvårdsåtgärd för att bevara enskilda arter och/eller bevara den biologiska mångfalden?

The examination of the adequate nature conservation methods in a natural reserve, to conserve a specific species and / or increase biological diversity is the subject of this study. This work is based on four species, that can be found during the Spring season, liverleaf, wood anemone, brimstone and woodpecker. The incidence and availability is studied and closely observed for these species in twenty forests, i.e. ten forests which are nature reserves and ten forests with the similar characteristics as the nature reserves habitat, but are not nature reserves in Gnesta mucipality, Södermanland. Measurements of the tree crown and the diameter of the tree trunks where noted to study how these factors could affect the outcome of the abundance and incidence of the four species.

Transporttidsmodellering vid provpumpning i heterogen jord : spårämnesförsök i en isälvsavlagring

When protection zones for wells are delineated, it is important to acquire good knowledge about possible travel time from different points in the catchment area to the well. Often, simple analytical methods are used for estimating travel times and the assumption is made that the hydraulic conductivity is relatively homogenous within the aquifer. Nevertheless, many aquifers are strongly heterogeneous which may lead to differences between estimates and actual travel times. As a part of the process to develop improved methods for delineating protection zones for groundwater supply wells, a tracer experiment was performed in a glaciofluvial esker formation in Järlåsa. On the basis of the experiment, a numerical flow model was created for the test site.The purpose of this master?s thesis was to apply the flow model to an aquifer where the hydraulic conductivity shows great variability and should be described by a stochastic distribution.

Regional utvecklingsplanering och grönstruktur : en studie av de gröna kilarna i Stockholms län

The aim of the thesis is to analyze the role of regional development planning concerning a regional perspective of green structure and to reflect on its future role. The target group of the study is foremost practitioners but also students of regional planning and development. Three questions are examined. 1) What view concerning green structure has the regional planning body of Stockholm County Council (RTK) communicated through the years? 2) Has this view contributed to generating a common understanding concerning green structure among the actors in the county? 3) Has this common understanding been referred to by actors in discussions concerning how this green structure should develop? The empirical material consists of documents from rtk, the County Administrative Board, the municipalities of the county, a network of ngo:s, as well as interviews with representatives from the above mentioned organizations.

XRF-analys av förorenad mark : undersökning av felkällor och lämplig provbearbetning

X-ray fluorescence (XRF) detection of heavy metals is a cost- and time-effective method for investigation of polluted areas. Compared to laboratory analysis, XRF analysis is limited by high detection limits and uncertainties in some situations. Preparation of samples is known to affect the results of measurements.The purpose of this thesis is to bring a deeper understanding of how different factors affect the results of XRF-analysis. A large number of measurements have been made with the instruments Niton XLt 700 and Niton Xli 700. Results from measurements of lead, zinc and copper have been analysed.This study has shown that a greater moisture content will give a lower measured concentration for the same sample.

Är förekomst av knäckesjuka i tallföryngringar mindre på stora naturvårdsaspar än på aspsly?

Pine twisting rust (Melampsora pinitorqua) is a parasitic rust fungus found all across Sweden causing damage resulting in lower quality and reduced tree growth in pine stands. In Sweden, the fungus is dependent on two alternate hosts; European aspen (Populus tremula) and Scots pine (Pinus sylvestris). Pine twisting rust has five different spore stages, two of them (uredinio- and teliospores) on the leaves of aspen. Injures on aspen caused by pine twisting rust is not extensive. On the other hand, when it infects the annual shoots of Scots pine it often results in a bent steam or even a top shoot breakage.

Skogen Brun : ett nedslag i västsvensk skogshistoria

After the last is age there was a long period when there was no shortage of forest for peoples needs. People living in Sweden could use the forest resources at their will. Around 4000 years BC the inhabitants of southern Sweden started to use the agricultural system and people become more stationary. The farms were located together in groups and together they formed a social association, the village. Successively the population grew and in some areas the forest started to become a finite resource.

Konceptstudie av drivmodul till bandskotare med hybriddrift

BAE Systems Hägglunds has a long history of producing high performance terrain tracked vehicles (mostly for military applications), and they are now aiming at developing a tracked forwarder with similar techniques.The forwarder will be of series hybrid type where a diesel engine via a generator will power the motors (one for each drive wheel). Thanks to individually controlled motors and the gentle rubber tracks, this forwarder is calculated to have a considerably higher average speed in the terrain and to be more gentle to the soil. The forwarder with a weight of 11 metric tons and a load capacity of 15 metric tons is specified to have an average working speed of 7-10 km/h, a top speed in terrain of 15 km/h and a top speed on roads of 40 km/h.This master?s thesis aims at developing a conceptual design of the forwarder?s drive module which includes electric motor, gear unit, brake and drive wheel.To investigate if the requirements can be fulfilled a study of the dimensioning loading scenarios has been carried out. The resulting needs regarding the torque has been considered in order to determine the required gear ratios for different motor options.

Större svartbagge Upis ceramboides i norra Hälsingland : förekomst, substratkrav och effekter av skogsbrukets naturvårdsåtgärder

Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.

Uptake of 137Cs by fungi and plants due to potassiumfertilization in Heby municipality in response to theChernobyl nuclear accident

The fallout from the Chernobyl nuclear accident resulted in large deposits of caesium, iodineand strontium as well as noble gases in various parts of Sweden. 137Cs has a radioactive halflifeof about 30 years and is therefore one of few radio-fission products remaining inmeasurable quantities in the Swedish soil. Radiocaesium behaves similarly to potassium insoil-plant systems and is easily absorbed by plants. It is important to understand how 137Csbehaves in different ecosystems in order to minimize the risk toward humans.The aim of this study was to determine how potassium fertilization influences radiocaesiumcontent in different forest plants and fungi. Potassium fertilizer was spread once in 1992 withapproximately 200 kg KCl per ha.

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.

Utveckling i Ammerån : att skapa ett hållbart fiske med hög kvalitet

Ammerån which is a small forest river in eastern Jämtland is a well-known river that has been a popular fishing river for a long time. The actual Ammerån begins downstream the lake Solbergsvattnet at Hammerdal and flows into the Indalsälven 10 km upstream Hammarstrand. The river environment switches between forests with wilderness feeling and open agricultural land. The entire Ammerån is today a nature reserve and protected from hydropower development. Fishing in Ammerån has mainly been focused on trout and grayling, and is so even today.

Fältinstruktion för skogsbruksplanering av inhemska skogar i Andinska Patagonien :

The thesis first objective was to develop field instructions for forest planning of native forests in Andean Patagonia, and the second objective was to test the plan on an actual property in the area. The thesis was limited to studies in the province of Rio Negro. Today, there are no official forest management plans for native forests in the Argentinean province of Rio Negro; thus, there is an obvious need for an official forest management plan with clear guidelines. To be granted permission to manage, i.e. through thinning, the native forests on a property it is required to have a forest management plan that is approved by the Forestry Board in the province in question (Thill, B.

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