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127 Uppsatser om Dehydration of soils - Sida 9 av 9

GIS och statistik vid dräneringsområdesvis kväveläckagebeskrivning i Halland

The last decades have shown increased nitrogen leeching from soil to water recipients. This is inSweden mainly due to over-manuring of agriculture land, effectivization of drainage systems and thedeclining extent of wetlands. The accumulated amount of nitrogen in water doesn?t only make itunsuitable for use by humans and cattle, but also decreases the biological diversity as well as negativelyaffect tourism and fish industry. In the most severe cases shallow maritime grounds can be completelydepleted of oxygen due to decomposition of the increased amount algae and plankton growth.This study have the aim to describe and quantify the nitrogen leeching from the Genevad drainagebasin, located in southern Halland, Sweden.

Utvärdering av osäkerhet och variabilitet vid beräkning av riktvärden för förorenad mark

I Sverige finns cirka 80 000 identifierade förorenade områden som i vissa fall behöver efterbehandling för att hantera föroreningssituationen. Naturvårdsverket publicerade 2009 ett reviderat vägledningsmaterial för riskbedömningar av förorenade områden tillsammans med en beräkningsmodell för att ta fram riktvärden. Riktvärdesmodellen är deterministisk och genererar enskilda riktvärden för ämnen under givna förutsättningar. Modellen tar inte explicit hänsyn till osäkerhet och variabilitet utan hanterar istället det implicit med säkerhets­faktorer och genom att användaren alltid utgår från ett rimligt värsta scenario vid val av parametervärden.En metod för att hantera osäkerhet och variabilitet i riskbedömningar är att göra en så kallad probabilistisk riskbedömning med Monte Carlo-simuleringar. Fördelen med detta är att ingångsparametrar kan definieras med sannolikhetsfördelningar och på så vis hantera inverkan av osäkerhet och variabilitet.

Optimerad höstveteetablering : en litteratursammanställning om såtid, radavstånd och utsädesmängd

This bachelor thesis is intended to gather the knowledge and experimental data on the winter wheat crop production relevant for Swedish conditions, with focus on sowing time, row spacing and seed rate. This essay is a literature study with a minor component based on interviews with farmers producing winter wheat. The work is divided into a background part where basic knowledge of winter wheat physiology, development and environment interactions are described and one part where results of field trials studies are presented. Optimal date of sowing winter wheat depends on annual weather variations. Because it is difficult to forecast the weather the choice of sowing date should be based on weather statistics, production experience and previous results depending on sowing date.

Svampar associerade med raps : betydelse för uppkomst och grödetablering

Oilseed rape is an important crop in Sweden and is grown on about 90000 ha today. The interest in oil seed pro-duction is increasing because of growing demand and high prices for oil seed both in Sweden and Europe. However, an increased intensity in the oil seed production can bring higher risk of yield losses due to fungal diseases. The purpose of this study was to investigate what different fungi are associated with oilseed rape under field conditions and if their incidence is correlated to crop establishment problems. This study was carried out in three parts: 1) investigations on fungal community structure in roots and rhizosphere soils from young spring- and winter rape plants sampled in failed respectively good establishment patches in four fields, 2) investigations on the pathogenicity of fungi isolated from oilseed rape in controlled environment and 3) investigations on the effect of different fungicide seed treatments on germination and early plant development in a field soil naturally infested with damping off- and Verticillium wilt pathogens. The studies on community structure using a combined approach of standard fungal isolation techniques and DNA based methods revealed a high fungal diversity in three out of four studied fields of spring rape and winter rape. For some unknown reason, very few fungal species were identified from the fourth field.

Rekreation och utomhuspedagogik i tätortsnära skog : planering av skolskog och rekreationsanalys för Sätra, en stadsdel i Gävle

This Masters Thesis includes a survey of recreational habits and the attitudes towards forests of the people of Sätra, a suburb of the city of Gävle. The study also includes the planning and design of a forest suited for education in the same part of the city. The thesis is a part of a project called Tätortsnära skog, commissioned by the Swedish forest agency. The project aims to survey the recreational habits of the general public in the regions of Dalarna and Gävleborg. Tätortsnära skog is focused on cities with a population of more than 20 000 inhabitants, of which Gävle, Sandviken, Falun and Borlänge all fall within the category.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Stureholm - en herrgårdsträdgårds historia, utveckling och framtida skötselmål :

Stureholm Manor and garden is a relatively young farming unit on clay soil in the north western part of Skåne, a province in Southern Sweden. Since the middle of the 19th century the landscape has been actively cultivated and has been transformed from oak forrest into farmingland of high efficiency. The industrial era during the 19th and 20th centuries meant new posssibilites for cultivation of these clay soils. With equipment like steam ploughs and the possibility to obtain fertilizers, the harvest increased considerably. This increased prosperity provided estate Stureholm with a beatuiful corps de logi, a manor. The trends prevailing in Europe around the turn of the century 1800-1900 against the growing industrialism, was turned into a artisan movement known as Arts and Craft. The Swedish followers idealized our Swedish history and they took the turn of a national romantic movement that later turned into neoclassicism.

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