Sök:

Sökresultat:

857 Uppsatser om Plantöverlevnad - Sida 24 av 58

Artrika vÀgkanter - hur pÄverkas de av slÄtter och underhÄllsdikning?

ABSTRACT This study is an exam work at the Department of Ecology at the Swedish Agricultural University, Ultuna, Uppsala. The field work was performed in the counties of Uppsala and VĂ€stmanland. Grassland areas, exposed to annual mowing, are known to host a variety of rare and red-listed vascular species. The area of these grassland are, however, decreasing in the landscape due to modern farming. The fact that roadside verges maintain regular mowing has proven to be a successful concept for many rare vascular plant species in this habitat. Vascular plants along roadside verges at the State road network were inventoried due to a government mandate during 1995 and 1996. As a result ?Species rich roadsides? were pointed out.

Effect of botanically diverse pastures on the milk fatty acid profiles in New Zealand dairy cows

Botanically diverse pastures are commonly used in New Zealand to reduce the ruminant environmental impact by reducing the methane production from the rumen digestion. In order to evaluate the effects diverse pasture species have on the milk fatty acid profile seventy-two lactating Friesian-Jersey crossbred dairy cows were used in a randomised block design with two replicates of six treatments. Six different pasture mixtures were fed at a daily allowance of approximately 15 kg DM/cow/day. The mixtures were categorised as either a simple or a diverse pasture. The simple mixtures all contained white clover with the addition of either a standard diploid perennial ryegrass (RG), a diploid high sugar ryegrass (HS) or tall fescue (TF).

Optimering av biologisk fosfor och kvÀvereduktion i ett reningsverk för hushÄllsspillvatten

In connection with Henriksdals wastewater treatment plant (WWTP) a smaller plant is situated called Sjöstadsverket where new methods for wastewater treatment are tested and evaluated in different process lines. On one of the lines experiments with enhanced biological phosphorous removal (EBPR), have been carried out to evaluate if it is a good alternative to traditional chemical phosphorus removal. This thesis evaluates the results from the experiments conducted during fall 2005.The incoming water from Hammarby Sjöstad consists of only household wastewater, which gives a wastewater with high concentrations of nutrients and organic carbon. This is partly positive, because one of the limiting factors for effective biological phosphorus removal is the lack of easily biodegradable organic carbon. The high concentrations of ammonium and phosphorus demand a high reduction to achieve the requirements of outgoing concentration.To optimize the process experiments with different recirculations and different aeration techniques have been made.

Vad behöver vÀxter för att vÀxa och överleva? : En studie om förskolebarns tankar om vÀxters behov

The purpose with this study was to examine what kind of knowledge children in preschool have regarding what plants are, and what plants need in order to grow and survive. By means of qualitative interviews I have let 12 children in the ages of 3 to 5 years answer questions regarding the subject.From the results it is obvious that the children in the early age groups already have some knowledge of what a plant is and can also mention a few basic factors for a plants survival. In addition, the results show that their knowledge increases with the childs age and that the conversations become more distinct with more resulting questions the older the children are.Keywords. Enviroment, plants needs, Preeschool, science..

Nya urbana tr?darters ?terh?mtning av fotosynteser efter v?rmeb?lja.

Tr?d ?r viktiga f?r att skapa h?llbara st?der. De utf?r ekosystemtj?nster som gynnar oss m?nniskor genom ?kat fysiskt och psykiskt v?lm?ende samt genom att bidra positivt till v?r ekonomi. Utformningen av st?der medf?r ett flertal utmaningar f?r urbana tr?d, d?r v?rmeb?ljor, torka och generellt h?ga temperaturer ?r n?gra faktorer som f?rsv?rar tr?dens ?verlevnad.

Optimization of Burner Kiln 7, Cementa Slite

In this report focus is put on the combustion process at a cement plant. Combustion is the heart of the cement making process and absolutely crucial to have under full control and well optimized. The fuel is put into the process through a burner pipe and this burner pipe is modified to reach a more efficient combustion. The primary target is to enable burning of heterogeneous alternative fuels and increase the production level. Other positive effects from this type of optimization is lowered specific fuel consumption and lowered CO2 emissions. A redundant burner is chosen for the project and overall the project steps are the following: 1. Installing a Jet air nozzle ring in a way so it can move both axially and radially due to temperature changes. 2.

Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes

Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.

Hydrolys av primÀrslam för förbÀttrande av biologisk fosforreduktion vid behandling av hushÄllsavloppsvatten [Hydrolysis of primary sludge for enhancement of biological phosphorus removal in household wastewater]

Hammarby Sjöstad is a new district of southern Stockholm built with focus on reduced environmental impact by recirculation of materials and sustainability. The environmental goals aim to cut the water consumption by half and a separate storm water treatment. Thus, the wastewater will be more concentrated and will originate from the households only. The Sjöstad project includes the idea of a local treatment plant for the household wastewater. To evaluate this possibility, Sjöstadsverket, an experimental treatment plant was constructed.

VÀxters upptag av spÄrÀmnen frÄn rödfyr : ett odlingsförsök vid tre rödfyrshögar i VÀstra Götalands lÀn

Burnt alun shale and lime is the residual product that was formed when alun shale was used as fuel to convert limestone to quick lime. The material contains arsenic, vanadium, molybdenum, cadmium, nickel, lead, and uranium among other elements. The aim of this paper is to examine the uptake of trace elements in vegetables grown on burnt alun shale and lime to determine whether or not the surrounding environment and humans are exposed to these elements by eating plant products. A cultivation trial was carried out where onion, carrot, and lettuce were grown on three mounds of burnt alun shale and lime in the Falköping area in Sweden. The treatments were burnt alun shale and lime mixed with peat, only burnt alun shale and lime, and a reference soil. The reference plots were natural soil mixed with peat adjacent to the mounds.

KartlÀggning av markberedning i svÄr terrÀng pÄ SCA Skog

Due to the requirement for reduced use of insecticides and the lack of competitive mechanical plant protection, you need a scarification with good result. This is often no problem to perform in normal terrain without technical barriers. However, in difficult terrain with large number of rocks and steep slopes, the result would be worse. The purpose of the study is, that in these areas with difficult terrain, to find out the scarified areas quality, describe the non-scarified areas conditions and find out where the limit is for the use of a traditional disc trencher. Findings indicate that there are usually not the machine that is the limit, but the driver of this.

Flödesanalys av laser- och limcell pÄ Volvo CE i Eskilstuna

Volvo Construction Equipment AB Component Division (CMP) I Eskilstuna har idag det globala ansvaret för utveckling och tillverkning av drivlinor till anlÀggningsmaskiner. De nya kraven pÄ nÀsta generations transmissioner har dock krav pÄ sig att vara mindre och lÀttare samt ha mindre inre förluster Àn den föregÄende. För att kunna möta detta krav krÀvs det att kopplingsaxlarna i tranmissionerna blir mindre. För att leva upp till detta samt en förbÀttring hos kvalitén pÄ förbanden sÄ introduceras tvÄ nya fogningsmetoder enligt laser- och lim/krympförband. I denna rapport klargörs flödet genom de tvÄ fogningscellerna.

Olfactory responses of the parasitic wasp, Trybliographa rapae (Hymenoptera: Figitidae)

Delia flies (Diptera: Anthomyiidae) are economically important pests in several horticultural crops. The control is commonly relying on chemical insecticides, though there are possibilities with biological control from the natural enemies in the field. An important natural enemy is the parasitic wasp, Trybliographa rapae Westwood (Hymenoptera: Figitidae) that lays eggs in the Delia fly larvae. The parasitoid larva and the host larva have a parallel development until the host dies within its puparium and an adult parasitoid emerges. The aim of this thesis was to understand the attraction to host- and food-associated plant volatiles of T. rapae, in order to enhance the effectiveness of the parasitic wasp as a biological control agent.

KvalitetssÀkring av hushÄllsnÀra avloppsfraktioner : vad krÀver livsmedelsbranschen?

On-site sewage systems are common on the countryside of Sweden with approximately one million on-site systems installed. Due to insufficient function, these contribute significantly to the total discharge of phosphorus to rivers and lakes, causing eutrophication. In order to reduce eutrophication and to fulfil one of the environmental quality objectives, the decision was taken by the Swedish Government in 2005 that 60 % of phosphorous in sewage sludge is to be recycled to arable land before 2015. To make recycling a reality, new solutions have to be found. Federation of Swedish Farmers (LRF) takes an active interest in this issue and has initiated this study. One problem is that the food industry is sceptical towards recirculation due to the risks that products from sewage systems may contain pathogens, heavy metals and unwanted chemical compounds, e.g.

Stenmaterial vid asfalttillverkning

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger pĂ„ tvĂ„ kopplade differentialekvationer som under arbetets gĂ„ng anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment pĂ„verkas av avvikelsen frĂ„n den optimala kombineringskurvan för vinklarna pĂ„ turbinens ledskena och löphjul, och Ă€r anpassad för ett referensaggregat med tillgĂ€ngliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sĂ€tts samman med frekvensregulator och elnĂ€t för att simulera aggregatets reglerstabilitet i önĂ€tsdrift.Verifieringen av turbinmodellen sker genom försök att Ă„terskapa de befintliga verkningsgradskurvorna med hjĂ€lp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med nĂ„got lĂ€gre maximal verkningsgrad.Verifieringen av önĂ€tmodellen sker genom att prova stabiliteten i nĂ€tfrekvens och turbineffekt vid stegpĂ„lastningar. Resultatet ger en stabilare reglerstabilitet Ă€n i verkligheten, men uppfyller Ă€ndĂ„ förvĂ€ntningarna pĂ„ en fungerande modell.This report describes the development of a new kaplan turbine model.

Portrayal of animal communication in wildlife documentary

Many people turn to documentaries for knowledge about animals, but do documentaries give us a truthful portrayal of animals and their behavior? This study looks at how the communication behavior of the portrayed animals is depicted in three episodes of The Life of Mammals. These episodes were observed after which the contents were compared to scientific literature on the same topics. The results show that quite little communication is actually shown in the episodes about plant predators and meat eaters and relatively much of it is shown in the episode named Social Climbers, involving primates. The matching literature suggests that based on the narrative and the accompanying footage, the viewer is getting a realistic picture, with the exception of a few questionable cases..

<- FöregÄende sida 24 NÀsta sida ->