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610 Uppsatser om Cultivated plants - Sida 16 av 41

Spårning av miljöstörande ämnen i Uppsala stads spillvattennät

To the sewer systems households, industries and other activities are connected. The wastewater is collected at treatment plants where a nutritious sludge is produced. The sludge does not only contain nutrients, but also hazardous substances originating from different activities in society. To reduce the flow of hazardous substances to treatment plants and to create a sustainable recycling of plant nutrients the Swedish Water & Wastewater Association has developed the certificate system REVAQ. This certificate requires a good quality of the sludge but also that the treatment plants maps the origin of the unwanted substances.

Klövviltets besöksfrekvens och bete i sydsvenska poppelplanteringar

Energy is an essential part of the society and for a sustainable future we need to use the energy resources in a sustainable way. The forest is Sweden?s most important resource for renewable energy and a higher production combined with shorter rotation periods (time from planting to clear cutting) can increase the access to energy. The tree genus poplar (Populus spp.) is interesting as energy resource as it has both high production and short rotation period. But browsing ungulates are a major threat to the establishment of poplar plants and therefore the poplar plantations need to be fenced in today. To use fences is expensive and time consuming; this makes it interesting to find more cost-effective solutions where there is no need to fence. The aim with this study was to look at the ungulates? occupation rate and browsing pressure in poplar plantations without fence.

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.

Barley starch, structure and properties

Starch is a naturally occurring substance in most plants and is used as energy storage. It is a component that mainly consists of amylose and amylopectin. Together they build a complex pattern which gives starch its specific properties. The proportion of amylose and amylopectin varies in different plants but generally starch consists of 25 % amylose and 75 % amylopectin. There have been discoveries of barley varieties containing 100 % amylopectin called ?waxy starches? or ?waxy barley? as well as varieties that have a high content of amylose, around 70 % and these are called ?amylotypes?.

Stjälkröksvamp (Tulostoma brumale) : stora eller små individer?

The spatial population structure of the saprotrophic basidiomycete Tulostoma brumale was investigated at a site in south eastern Sweden. Sporocarps were mapped and collected, and somatic incompatibility tests between mycelial cultures cultivated from the sporocarps were used to identify genets. Calculations of the size and numbers of genets and their distribution were performed. The spatial distribution of the tested sporocarps and the identified genets are presented graphically in a grid. The total number of identified genets within the investigated area (1210 m2) was 27 based on 48 tested sporocarps.

Fukthalt i GROT - påverkande faktorer :

This study was carried out at the request of the bio energy company Naturbränsle. The company handles annually 750 000 m3 of chips from logging residues from a large area, from Östergötland in the south to Härjedalen in the north. In that area, about 50 bio fuel plants are customers. When Naturbränsle deliver chips from logging residues to their customers, the moisture content varies from 30 % to 60 %. The aim of the study was to sort out the affecting factors on the moisture content in the chips during handling and storage processes.

Odlingsstrategier på organogena jordar : en studie om beslutsfattande bland KRAV-anslutna lantbrukare

This study examines how farmers certified by KRAV face proposed regulations on organic soils put forward by KRAV economic association among others, and how they are affected economically. These soils are, from an environmental perspective, interesting as a target for production regulations as they cause greenhouse gas emissions through decomposition of organic material when cultivated. The regulations advocate that organic soils should be grown with pasture where soil cultivation is only allowed every fith year which implies that possible adjustments of cultivation have to be made in order to fulfill the regualtions. Collection of data have been made through a questionnaire sent out to 574 farmers certified by KRAV. The answers have been analysed using a decision making model and statistical findings suggest that proportion of organic soils, type of production, economic conditions and farmers? goals and values have an influence on whether the regulations and potential cultivation adjustments have been considered or not.

Obtaining high quality textile fibre from industrial hemp through organic cultivation

AbstractThe urgency to find alternative fabrics to conventionally produced cotton is increasing as vast amounts of agrochemicals are used and a lot of irrigation is required. In this literature survey the potential of organic cultivation practices to produce highly qualitative hemp fibre, suitable for the textile industry, was investigated. The definition of a fibre in the textile context as well as of the qualities that are essential for a textile fibre was necessary as a base for the discussion in this thesis. The quality parameters looked at were fineness, strength, length, friction, and colour. The impact of external growth factors and plant development on these quality properties are discussed.

?R KUSTN?RA ALK?RR I BOHUSL?N ETT ?BLUE CARBON? HABITAT?

In coastal wetlands carbon/organic matter can be stored for long periods of time thanks to, among other things, the presence of water which slows down the decomposition. Because of this, restauration and management of such habitats have the potential to decrease the emission of greenhouse gasses and help mitigate climate. Internationally these environments are called ?blue carbon? ecosystems. In Sweden, alder (Alnus glutinosa and Alnus incanata) covered wetlands along the coast is a nature type that potentially could function as a ?blue carbon? habitat.

Undersökning av självspridning av contortatallen i norra Sverige

Over the past 40 years 600 000 ha of lodgepole pine (Pinus contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions. A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.

Energiewendes påverkan på det nordiska kraftsystemet

Both the German and the Nordic power markets are seeing dramatically changed conditions due to an ongoing process of expanding the share of renewable production in the systems. For the German part this comes from heavy subsidies which have led to an explosive development in installed capacity of photovoltaic and wind based production. After the Fukushima incident it has been decided to shut down all Germanys nuclear plants. This capacity drop is however not of the same magnitude as the increase in renewables, but will impact the stability of the power system. The Nordic power system which already has a surplus of power sees an even further increase, coming mainly from construction of new nuclear plants in Finland and a general increase in wind farms.

Energy efficient storage of biomass at Vattenfall heat and power plants

Storage of biomass is often associated with problems such as heat development, dry matter losses and reduction of fuel quality. The rise in temperature can potentially cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles can cause health problems in the surrounding. The dry matter losses and reduction of fuel quality can have economical effects. The aim of this thesis project is to develop guidelines on how to store large amount of biomass at Vattenfalls heat and power plants in an optimal way.

Biodiversitet av evertebrater på vegetativa tak

In a city sometimes conflicts arise between either to save the species-rich vacant lots where many species thrive, or to build new buildings. Green roofs can then serve as a refuge for plants and animals that have had their natural habitat destroyed or diminished. Today we know too little about green roofs contribution to the biodiversity in the cities. We also know very little about how various types of vegetation on roof can increase biodiversity and its ability to attract different species.The aim with this study was to examine how different types of vegetation on the roofs affect the biodiversity of the invertebrate and how species-composition and number of individuals differ between the roof- and groundlevel.This study has been carried out on Augustenborg Botanical Roof Gardens in Malmo, and in an area about 1.5 kilometers away from Augustenborg. Three different types of vegetation on the roof and ground floor were selected: sedum- ruderal and grass.

Tree species traits response to different canopy cover for 34 tree species in an enrichment planted tropical secondary rain forest in Sabah, Malaysia

Tropical rain forests only cover around six percent of the world?s land area and contain around 70 % of the world´s animals and plants. Tropical rainforests have been, and still are, negatively affected by human activities. These activities lead to forest degradation which has negative impacts on production and biodiversity. Between 1970-1980 forests in Borneo, Sabah, Malaysia, was subjected to intense logging.

En bra plats för lek : kreativ och tillgänglig lekplats i Hedemora

For an outdoor environment to function optimally as a playarea requires that it is flexible, that is, contains places and elements that give room for the imagination and for own interpetretations, and also that the children in some way can influence and change their surroundings. It is also important to have variety, both in the sense that the playground has a unique character that distinguishes it from other places, and that it allows many different games and activities. There should for example be room for both wild games of running and moving around where many children can participate, and calm corners to withdraw to for rest or quiet play. A good playground should surprise, challenge and encourage children to discover their surroundings. One way to achive this is to use plants and materials from nature, whose irregular forms and structures can become interesting elements to explore. Vegetation also gives sence-experiences of various kinds, materials like twigs and leafs to play with and a place to play house.

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