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766 Uppsatser om Soil conservation - Sida 27 av 52

Beslag eller buckla? : En studie av platta järnfragment från hallhuset i Birkas Garnison

This paper deals with flat iron fragments from the Viking Age hall situated in Birkas Garrison, Adelsö parish in Uppland. The aim of the study was to identify which objects these flat fragments were originally derived from. The aim was also to discuss the function of these objects and their presence in the hall. This would hopefully increase the knowledge about the hall and the warriors who lived and worked there. In some cases the fragments form and placement in the hall has not provided enough information to classify the object from which they derived.

Flygplansavisningens miljöpåverkan vid svenska flygplatser

The aim of this thesis was to answer a number of questions about the environmental consequences of aircraft de-icing. A further aim was to suggest how the environmental consequences due to the release of de-icing fluids can be measured and reduced.The main impact of the aircraft de-icing on the environment is due to the large oxygen demand for the degradation of glycol based de-icing fluids which are released in the environment. The effect of the increase in oxygen demand depends on where the degradation occurs in the ecosystem. In a sensitive ecosystem, the large demand of oxygen could provide an anaerobic environment which would be harmful for many types of organisms.In order to reduce the negative effects of the applied de-icing fluid, there is some type of collection system at every regular airport in Sweden. The methods of collection can be divided into two general groups, hydrological isolation or vacuum sweeper trucks.

Gränser i Grödinge : Om hägnadsanläggningars funktion med utgångspunkt i en fosfatanalys av RAÄ 78 samt RAÄ 79 i Grödinge sn på Södertörn

This paper deals with the question of when hill forts ? or enclosed mountains ? were built and to what purpose, by examining two enclosed mountains (RAÄ 78 and 79) in Grödinge parish in the province of Södermanland. A phosphate analysis was conducted to trace anthropogenic activities. The analysis showed only a slight elevation of phosphate content in the soil. A histogram indicated that the elevations were not normally distributed, which could suggest that they were caused by anthropogenic activities.

Rumslig fördelning av grov gammal tall i Uppsala stad med tallticka som indikator på höga naturvärden :

Fragmentation and reduction of forest area is a threat for many forest species and their habitat. Deficiencies in forest quality, such as lack of dead wood and old trees, are one explanation of the threat. The most important action to prevent the continued loss of forest types is to protect forest, but also to restore and to create areas that not previously had high nature values. Hence one of the key strategic roles for Fritid- och Naturkontoret, Uppsala municipality, is to monitor biodiversity in the context of urban planning. The majority of the Uppsala municipality residents live in urban areas and most of them spend some of their spare time in natural areas in cities and their immediate surroundings. Exploitation in and around Uppsala is high, but it is important that there is enough nature close to houses to meet the residents? needs of recreation.

Bevarande av naturvärdesträd i enlighet med FSC och Holmen Skogs naturvårdspolicy :

In the end of 1998 the company Holmen Skog AB was certified accordint to the FSC system with an area of 1 036 000 hectare. After that Holmen Skog AB has been working actively with the nature conservation in the forestry. In order to control the quality of the company?s nature conservation in final fellings they started a yearly inventory which is called BAKRUS (Judgement of ecological and culture care in relations to policies for a persevering silviculture). After 1999 the control was expended to include all actions in the forest.

Askgödsling och dess lämplighet i torvmarksskogar tillhörande Sveaskog Förvaltnings AB : en litteraturstudie

During whole-tree harvesting, there is a risk that the soil will become impoverished of nutrients. To prevent this, nutrients are returned to the harvested site as wood ash. This action also reduces the risk of soil acidification. Nevertheless, the ash does not result in any increase of tree growth if it is added on mineral soils, which is where the measure is most commonly used in Sweden. Due to the lack of growth response, the interest from landowners is small, which is why ash amendment today is not done enough to compensate for the need.

Topografins inverkan på markvattenhalten i ett jordbruksdominerat avrinningsområde

Topography is an important parameter for catchment hydrology, since it is a driver for water flow. Moreover, topography serves as a basis for hydrological models, e.g. ?Top-model?, which is based on a topographical wetness index (TWI). Few studies of TWI have been conducted on agricultural catchment scale. Four fields were studied in a Swedish drained agricultural catchment in order to evaluate the influence of topography on soil wetness.

Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark

This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.

Möjligheter att minska kväveutlakningen genom att anpassa kvävegödslingen till variationer inom stråsädesfält

Due to excess precipitation that cause runoff, all soils in Sweden naturally leaches nitrogen.High leaching from arable land is an environmental problem when the runoff reacheswaters. In the international agreement, Baltic Sea Action Plan, the aim is to reduce therunoff of nutrients. Sweden has agreed to reduce its load of e.g. nitrogen to the Baltic Sea.One of the proposed measures is an increased use of site-specific N-fertilization, which hasbeen shown to increase nitrogen use efficiency and therefore also reduce the nitrogen runoff.Either yields are increased with the same total amount of nitrogen, or the total quantityof nitrogen is reduced with preserved yield levels, which is profitable for the farmers.The dynamics of nitrogen leaching differs between top dressing applications above orbelow the economical optimum. There is a consensus about a difference in the dynamics,but not about its magnitude.

Flygbildsanalys av trädskiktets status efter brand : en metodstudie

During the past years fire has been identified as an important factor for nature conservation in the forest landscape. To accurately quantify the size of a burnt area is obviously important, but also to quantify the degree of fire damage to the tree canopy. Such data are important for assessing the conservation value, and to support planning and management of the burned area in the future. I have examined how to estimate the status of tree crowns after fire from interpretation of aerial photographs. This is possible because fire changes the structure of tree crowns and this influences the colours in aerial photographs by spectral reflection. Included in the study are four areas, three of which burned in 2005 and one in 2006.

Risk och krishantering : bevarandepolitik och normaliseringsproduktion

In this essay, Risk and crisis management Conservation policy and normalization production, I discuss how societies, communities and individuals are responsible for the handling of catastrophes and crises. Risk and vulnerability analyzes are parts of modern risk and crisis management. The purpose of these analyzes is to prepare people and organizations for any crises. For managing this it is necessary to comprehend, be able to change mindset in creating concrete tasks and inform others.The purpose of this essay is to analyze modern risk and crisis management by studying empirical material, such as interviews, observations and literature. My aim is to combine these materials and study how they cooperate.One of the findings in this essay is that risk and vulnerability analyzes are of great complexity. These analyzes require a discussion in order to identify the development of the society's crisis management system, as well as the continued support of the individuals that have a responsibility for preventing and preparing their organizations..

Förskolebarns motoriska utveckling : -Hur en förskolegård bör utformas för bästa tänkbara utveckling av barns motorik

The purpose of this study was to interview different groups of people (preschool teatcher, parents and theire childen) involved in preschool about their view on outdoor activity and children´s motoric development, and how a preschool yard should be designed to promote childrens development.All parties regard outdoor activity as very important for the development of children. They also think that the outdoor environment today is good but that it could be improved by including some trees and hills. The yard should also contain soil, sand, clay and water. The children prefer grass on the ground over other substrates. This study also gives good indications to decision makers how to build new or to reconstruct pre-school yards in the future..

Planering för friluftsliv, biologisk mångfald och skogsbruk i skogsmiljö

Vallentuna municipality in Stockholm County, is planning to develop a management plan for a forest area owned by the municipality. The property is an urban forest and the hiking trail Roslagsleden runs through it. Hence the municipality intends to take extra care of the outdoor recreation interests, as well as forest biodiversity, but at the same time use the area for forestry. This study discusses how these three interests, recreation, biodiversity and forestry, differ in their views of how a forest should be managed, where they disagree and how they can coexist in the management of this area. In this study, a vegetation mapping of the area and an assessment of the forest?s conservation values was carried out.

Betula : arter och sorter

As birch is one of the most common trees in Sweden, and probably one of the easiest for someone who lives here to identify, it is interesting to note that most people do not know how variable the genus is and how widely it is distributed across the northern hemisphere. One can find birch growing at both high and low elevations, demanding different soil conditions and preferring varying amounts of sunlight. Many people may also be surprised to hear that the colour of the bark can vary from bight white to almost black, and different shades of pink, orange and red can also be displayed. This, together with the astonishing beauty of the genus, the important role as a pioneer in many ecological systems and the difficulty in sorting out the taxonomy of the genus, constitutes the background of this thesis. The thesis is written at the Department of Landscape Development in Alnarp, Sweden with Kenneth Lorentzon, researcher at the Swedish University of Agriculture as a supervisor. The aim of this thesis is to highlight which species and cultivars within the genus Betula could be appropriate for horticultural use in Sweden.

Är bor nödvändigt vid skogsgödsling i Sverige?

This thesis has been made on behalf of SCA Skog AB to assess the need of boron in Swedishforest fertilization. Boron has been added to Swedish forest fertilizers since the beginning of the1980s. This makes the fertilizers more expensive and therefore has the necessity of boron inSwedish forest fertilization been raised.The Swedish bedrock generally contains small amounts of boron. The boron in the bedrock istightly bound to the mineral tourmaline and mostly unavailable for plants. This leads to that thecontribution of boron to the soil from weathering is very low besides soils with marinesediments.

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