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494 Uppsatser om Excavated soil - Sida 26 av 33

Fosforförluster från lantbruket och dess bidrag till övergödning av sjöar och vattendrag i Växjö kommun

The possibility for plants to utilize phosphorus in soil is a prerequisite for conducting agricultural production, both small scale and professional. Spreading of phosphorus fertilizers and manure is therefore seen as a necessity in today's agriculture in order to achieve high yield. Manure management, livestock farming and manure storage could contribute to the eutrophication of lakes and rivers. For instance, when the ground becomes saturated, phosphorus leakage could be seen in surface runoff or in point sources resulting from inadequate manure storage management.In the municipality of Växjö there is still many bodies of water that do not reach the Swedish environmental water quality standard of "good ecological status". This thesis has therefore analyzed the manure management and storage on agricultural farms which may have contributed to eutrophication in the municipality.The method for this thesis was a literature study, a questionnaire survey with 820 receivers and a summary of issued inspection reports from 2013.The results highlight the ways in which agriculture may have contributed to the eutrophication of lakes and streams in the municipality of Växjö.

Do retention trees affect the composition of ectomycorrhizal fungi? : a comparison between clear-cuts areas with and without retention trees in pine forests

Under det senaste årshundradet har de svenska skogarna genomgått en omfattande förvandling, från mer eller mindre naturligt dynamiska till hårt brukade skogar bestående av monokulturer av tall eller gran. Denna förändring har lett till en minskning av den biologiska mångfalden, att många arter som är beroende av skog har minskat radikalt och hotas av utrotning. Som ett försök att främja variation, biologisk mångfald i allmänhet och förhindra minskningen av rödlistade skogsarter introducerades i början av 90-talet en viss naturvårdshänsyn i brukade skogar. I den här studien utvärderas den påverkan som kalavverkning har och den betydelse hänsynsträd har på artsammansättningen och förekomsten av ektomykorrhizasvampar (EMF) under de första 20 åren efter kalavverkning. Studien utfördes genom extrahering och identifiering av svamp-DNA från jordprover tagna på kalavverkade ytor, nära hänsynsträd och i gammal skog i ett begränsat geografiskt område i norra Sverige.

Marknaden för skogsvårdstjänster : en undersökning bland privata markägare inom en region i Värmland

This work broadly illuminates the conditions for increasing the commissions of forestry services within the whole, or parts of, the western regions of Stora Enso?s operating area. Through a questionnaire, a survey was made examining whether the owners of the forests themselves do the forestry on their woodlands. This foremost concerns the pre-commercial thinning, but also planting and soil scarification. The survey also shows who are buying the most part of their forestry services and who are carrying it out themselves.

Vattensork och åkersork - skadegörare i svensk fruktodling

There are two species of voles that cause damage in Swedish fruit production: the water vole (Arvicola terrestris) and the field vole (Microtus agrestis). Both species make the most damage during the winter season. The water vole makes subterranean burrows and cause serious damage by gnawing on the tree roots. The field vole seldom makes burrows and gnaws the bark at the base of the tree trunk. In recent years there have been several reports about increasing vole damage.

Identifiering av deponerat material i en deponi samt metodikförslag för upprättande av vattenbalans.

Högbytorp is Ragn-Sells? largest waste facility and it is located north of Stockholm. There is an old landfill still in use, but at the end of this year it will be closed. The waste deposited on the landfill can, through decomposition, give rise to a large amount of methane gas, which is an energy rich gas that can be used for heat and electricity production. To receive a relatively large amount of gas, the decomposition requires a high moisture content in the waste.

Påverkan från den förväntade klimatförändringen på tillväxten i norra Sveriges skogar : En litteraturanalys

This is a literature review of how the climate change affects the forest growth innorthern Sweden. The temperature will rise about 5 °C with the largest increase in thewinter season (December - February) and the CO2level in the atmosphere is expected tobe doubled. Precipitation patterns will change and increase with 25-35 % and theprecipitation will be in form of rain rather than snow. Today the forests in northernSweden are entirely dominated by coniferous stands. This may shift with the climatechange and results in a larger number of deciduous trees, preferably birch will becomestronger and grow better and faster.

Nya träd för stadsmiljö

Trees in urban environment are exposed to extreme conditions, foremost the ones that grow in the hard packed soil along our streets. They are also exposed to damaging insects and fungal diseases both local and new ones spreading from South Europe. The global warming with warmer temperatures provides a longer growing season, making it easier for insects and fungus to establish a habitat. Based on these facts new tree species need to be available for future urban plantings.To determine what these trees would be an interview study began. Six people were selected who have experience in the field of urban environment planting.

Övergödning av Mälaren : Betydelsen av antalet beviljade dispenser av stallgödselspridning vid Sagån

Eutrophication was recognized in the early 1900's and results in severe algal blooms, increased biomass production and eventually leads to an altered ecosystem. In Mälardalen we find the most eutrophic lakes. Most of the applied phosphorus and nitrogen into seas and oceans comes from agriculture, and the nutrients losses are affected by local weather conditions and soil type. Guidelines for storage and distribution of manure were introduced in the 80s, and the rules were strengthened January 1, 2010. Localities and previous county administrations can whether there are special reasons, grant an exemption for manure application during winter-periods despite the current ban.In this essay I have examined how many exemptions of manure application that has been granted at the Sagån river, and what implications it has for the eutrophication of Lake Mälaren.

Vallört som växtnäringskälla : växtnäringsförsök och litteraturstudie

Russian comfrey, Symphytum x uplandicum, was tested as a plant nutrient source in a trial with tomatoes. Comfrey liquid was produced by Stiftelsen Holma i Höör. Tomato plants of the cultivar Aromata planted in a medium of soil:peat (1:1) enriched with organic nutrients and lime, were fed with comfrey liquid plus Biofer, in three different concentrations. Two different concentrations of BioRika were used as comparison, along with an unfertilized control group. In the comfrey treatment I a total amont of 1g N, 0,23 g P, 0,84 g K, was given to the tomatoes.

Fungiciders påverkan på kvävehalten i höstvete : hur påverkar användandet av fungicider utnyttjandet och inlagringen av kväve i höstvete?

A common perception is that fungicide treatments increases yield, but that the nitrogen of the particular grain is diluted so that the overall removal of grain nitrogen from the field remains unchanged. The aim of this paper is to demonstrate that a healthy crop reduces the risk of nutrient loss from agricultural land. The results from genotype and plant protection trials often show constant nitrogen content in the grain, although the yield has been increased. Results from such experiments are therefore processed in order to confirm this and show that it is no statistically significant difference between the protein content (and also nitrogen content) in crops which have undergone fungicide treatment compared to crops which remained untreated. The trials processed have been carried out in the southernmost part of Sweden and are distinguished to concern winter wheat production.The explanation to the results is that a healthy crop is able to maintain the biological functions of the plant in a more efficient way than a crop damaged by a fungal infection.

Inventering och riskklassning av nedlagda deponier enligt Metod för Inventering av Förorenade Områden (MIFO), Uppsala kommun : Spridningsförutsättningar och transportprocesser i deponier samt ansvaret för förorenad mark

This master thesis encompasses an inventory and risk classification of four disused landfills within the municipality of Uppsala, Sweden. The model of the classification; ?Method of Surveying Contaminated Sites? is developed by the Environmental Protection Agency and can be used as a framework to investigate and describe the environmental damage and the level of risk for each object. The risk classification model has a rating from 1 to 4, where 1 represents a very high risk while 4 is a small risk. Risk class depends largely on the type of land use that exists on the object, and hence, various benchmarks must be taken into account.

Cooking banana farming system in rural Uganda : a comparison between agroforestry systems and non agroforestry systems

The demand for food, feed, fibre and fuel has increased in Uganda over the past 50 years due to population growth. Recurring extreme climate events such as drought and flooding, in combination with large-scale land degradation, have led to declining crop yields. Lack of equipment, money and socio-economic issues has contributed to low yields. However, the soils in Uganda have the potential to produce much higher yields than they do today. This study, which was carried out in April-June 2013 in Kkingo District, south-east Uganda, examined the effects of agroforestry on yield of cooking bananas in small-holder farming systems. Six farms practising agroforestry and six farms with no agroforestry, which were chosen in cooperation with the NGO Vi Agroforestry, were compared.

Fortsatt gran eller självföryngrad björk efter stormfällning? : en ekonomisk analys

The southern part of Sweden, Skåne, is frequently exposed to storms causing great damage to Norway spruce (Picea abies L. Karst.) stands. A storm during the winter 1999/2000 raised the attention of the problem. A lot of forest owners got large areas of spruce stands wind thrown during this storm. Can naturally regenerated birch (Betula sp.) be an alternative on these wind-exposed sites? This was the main question I was facing when discussilig the problems with Esben Möller Madsen, Söderåsens forest district. The aim of this master thesis was to present an economic analysis of Norway spruce versus birch.

Arboga Mekaniska Verkstad : Förslag på saneringsåtgärder gällande gjuteriet och plåtverkstaden

The industrialization in Sweden has increased the large number of areas that have been contaminated with various types of pollution. One of those sites are the property Höjen 3:24 in Arboga where ?Arboga Mekaniska Verkstad? once been. The property wants to increase the use of the old former foundry building with the adjacent ?plate-workshop? and believe there are two options for the building: That the building either should be used as a warehouse/concert hall, or rebuilt into a cultural center. An environmental evaluation has shown that the levels of heavy metals are over the Swedish environmental protection agency guidelines of less sensitive land.

A survey of cassava plants in the coastal region of Tanzania showing severe symptoms of cassava mosaic disease

Cassava (Manihot esculenta Crantz) is a root crop that plays an important role in many households in Africa. It is sometimes called ?Africa´s food insurance?. The advantages with the crop are that cassava is drought-resistant and it can grow in a semi-dry land. It is a perennial crop and does not require much labor.

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