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474 Uppsatser om Crop failure - Sida 5 av 32

Inokulmmängdens betydelse för utveckling av vetets stråbasröta orsakad Fusarium graminearum : utvärdering av ett biotest

Fusarium graminearum is one of the most important pathogens on cereals and causes major crop losses around the world. The most cultivated cereal in Sweden is winter wheat. F. graminearum produces both sexual and asexual spores for dispersal. Multiple factors affect the production of these spores.

Restriktioner av växthusgasemissioner : hur påverkas lantbruksföretagens ekonomi och produktionsinriktning?

The agricultural sector accounts for about 13 percent of the total load of greenhouse gas emissions from Sweden (Swedish Environmental Protection Agency, 2007). The Swedish objective to reduce the greenhouse gas emissions with 40 percentage units to the year of 2020, based upon the year of 1990, might imply stricter regulations for Swedish farmers. A regulation or other forms of economic incentives is probably necessary to reduce the emissions originating from the agricultural sector. This study aims to investigate the economic and managerial impact on two agricultural firms with differing production system given that a constraint on green house gas emissions is introduced. Gases included in this study are carbon dioxide, methane and nitrous oxide.

Grund plöjning med Kvernelands Ecomat och Ecomat Seeder : resultat från undersökningar genomförda år 2005

The Kverneland Ecomat and The Ecomat Seeder has been tested in three different field studies. All the studies were conducted on soils with different clay content during 2005 in Säby outside Uppsala. In one of the trial spring ploughing with the Ecomat and spring ploughing and seeding with Ecomat Seeder were compared with conventional autumn mouldboard ploughing and spring mouldboard ploughing to conventional depth (22-23 cm). In this study the quality of the seedbed, the number of emerged plants and weeds, the pentration resistance and the yield were examined. Shallow spring ploughing (10 cm) with the Kverneland Ecomat has shown to be a good alternative to conventional autumn ploughing when growing spring crops. During the season 2005 tilling with the Ecomat resulted in a higher yield than conventional ploughing. In 2002-2005 the average yield for shallow spring ploughing was 4 percent higher than after conventional autumn mouldboard ploughing and 10 percent higher than after spring mouldboard ploughing to conventional depth (22-23 cm). In the other two studies, ploughing to different depth in the autumn with the Ecomat was compared with conventional mouldboard ploughing and stubble discing.

Kvalitetsförändringar hos rajsvingelsorterna Hykor, Perun och Paulita under första skörd :

Today, high-yielding leys of good quality are a must for Swedish dairy and beef enterprises if they are to become profitable. Thus, it is of interest to evaluate the quality of the recently released high-yielding Festulolium hybrids ((Festulolium braunii (K.Rich.) A.Camus). The aim of this project was to determine at what phenological stage three different Festulolium hybrids should be cut in order to get the highest nutritional value. The hybrids studied were Hykor, Perun and Paulita. In the study I also investigated if leaf proportion of the crop could be useful for predictions of the crop content of metabolizable energy. The cultivars were grown in plots within a variety trial with ryegrasses.

Plantering av gran (Picea abies) på kalhyggen och självföryngring under högskärmar av björk (Betula pendula och Betula pubescens) : föryngringsresultat 7-10 år efter avverkning

The aims of the silvicultural method natural regeneration of spruce (Picea abies L. Karst) in birch (Betula pendula and pubescens) shelterwoods are to establish a new stand of tree seedl-ings and to protect those from high groundwater levels, frost damages and grass competition during its first life years. The aim of this work has been to (i) describe how shelterwood and stand characteristics influ-ence the results from using natural regeneration of spruce protected by a shelterwood of birch, and to (ii) compare those regeneration results with planting of spruce after soil scarification in clear-cut areas. Totally 17 harvesting sites have been inventoried and 15 of those included natural regenera-tion in birch shelterwoods, and two were subjects to soil scarification and planting of spruce. The sites represented 7-10 year old final cuts and are located in the coastal (eastern) region of the province of Norrbotten in Sweden. In all areas shelterwood and stand characteristics, as well as the number of main crop seedlings and the height of the highest main crop spruce seedling, were estimated and registered in all areas.

Timeliness cost for agricultural sprayers : weed control in cereal crops

Evaluation of machinery costs is necessary for selecting appropriate farm machinery. Timeliness cost due to untimely operations is an important component of machinery costs. Timeliness costs can be high for crop sprayers, since pesticide application must be carried out within a short time interval. This Master thesis investigated the timeliness cost and the probability of a suitable workday for spraying. Timeliness factors were estimated for four different crops (oats, spring wheat, winter wheat and barley) using historical weed trial data.

Föryngringsresultat och beräknad virkesproduktion i naturligt föryngrade tallbestånd i Västerbotten under mitten av 1990-talet :

According to the Board of Forestry, in Västerbotten, many natural regenerations of Scots pine (Pinus sylvestris) carried out on privately owned forest in the middle of 1990 in Västerbotten have rendered a bad regeneration outcome and will provide a low future forest production. The Board of Forestry believes that the negative result can be explained by the fact that the regeneration has been carried out in wrong locations and that scarification failed to work as planned. In order for an accepted rate of regeneration the guidelines of the Forrest Act require, not less than 10 years after final cutting at natural regeneration, that there should be at least 1300 (site indices 16 m) - 1700 (site indices 20 m) main crop stems per hectare. Main crop stems are defined as stems according to the place of growth and appropriate tree type, in addition with regard to quality, stage of development and damage risk have a prospect of succeeding. In addition main crop stems should be separated by surface so that the proportion sample plots with 3 meters radius, and lack main crop stems, are not more than 10 % of site indices 14 meters or higher.

Medskyldig till folkmord? En studie om internationella samfundets inblandning i folkmordet i Rwanda 1994.

The Rwandan genocide 1994 was a well-planned and ethnic based act that killedapproximately 900 000 people. The UN and the colonial powers are getting much attentionand are worldly discussed about the failure of interference before and during the genocide. Inthis study the history of colonial Rwanda will be analyzed and the UN relation will bediscussed. This will be done by examining how the colonial powers have affected Rwandathrough history and how the UN have responded upon the challenges towards Human Rights.Questions about accountability and failure will also be discussed and analyzed. This has beendone by analyzing highly reliable documents and books by NGOs and scholars.

Varumärkesvård i tider av kris : En fallstudie om återhämtning till följd av ett produktfel

This study is about how a swedish brand within the food industry that experiences a crisis following a product failure. It focuses on three areas following the crisis and these are crisis management, recovery strategies and brand management. This study seeks to explain how these areas interact in relation to massive exposure to mass media and how they interact restore the brand's potential loss of reputation. This study was conducted as a case study with a deductive and qualitative approach. The data gathered to this study was mainly based on newspaper articles and complemented with semi-structured interviews with twelve local retailers of the brand..

KVÄVEUPPTAG HOS FÅNGGRÖDORNA VITSENAP OCH OLJERÄTTIKA VID OLIKA ETABLERINGSMETODER :

The object with this thesis is to evaluate which of the catch crops oil radish and white mustard in combination with establishment method, give the most effective nitrogen uptake. The main purpose of the catch crops is to reduce leakage of nitrogen. They are sown after the main crop and killed before the next crop. In Sweden the farmers gets subsidies to establish catch crops. The thesis is limited to the trail L3-9010 sited at HS- Malmöhus, Borgeby Gård, 237 91 Bjärred, Sweden, 2007. Only treatments with oil radish, white mustard and the reference treatments were studied.

Attitudes towards hedging by diversified and non-diversified farmers : a comparative qualitative study

Deregulation on the market for agricultural products leads to a more globalised market with increasing price fluctuations. This, in turn, places the farmer in positions influenced by new risks but also improved opportunities. The farmers are faced by uncertainty in terms of financial outcome. To be able to utilise these new market conditions it becomes increasingly important for farmers to continuously follow the price trend, and to develop strategies how to manage the risks exposed by a volatile market. Farmers with different conditions perceive risk in different ways. Hence, their risk management behaviour will vary.

Optimering av multiprocessorsystem med hjälp av schemaläggning

A well known optimization-problem of multiprocessor system is scheduling of tasks. In this paper I use a variant of previous known algoritm, (Fast Critical Path) for scheduling real-time tasks on a multiprocessor system. This is made in a simulation study in MATLAB. The system architecture is assumed to be a MIMD- machine, (Multiple Instruction stream Multiple Data stream) with bus-typologi and message-architecture. Scheduling was made on this system where the number of processors varying from five to ten.

TCP/IP i taktiska ad hoc-nät

TCP (Transmission Control Protocol) is a transport protocol designed for the wired Internet. In wireless networks packet losses occur more frequently due to the unreliability of the physical link. The main problem is that TCP treats all losses as congestion, which leads to a lower throughput. Ad hoc networks are multihop wireless networks of mobile nodes, where each node can allow other packets to pass through it. Topology changes often occur and may lead to packet losses and delays, which TCP misinterprets as congestion.

Riskmodell för kabelsträckningar i mellanspänningsnätet i Sverige

The society of today is largely dependent on electricity and the dependence does not show any signs of declining. Reliability of supply will become increasingly important in the future and it is therefore important to investigate factors affecting the failure rates in electrical components.Sweden was hit by several severe storms during the 00?s. As a result of this many overhead lines in forests were cablified. In urban areas underground cable systems have been the norm for many years.

Fysisk aktivitet som egenvårdsåtgärd och dess effekter vid hjärtsvikt hos patienter över 65 år : en litteraturöversikt

BackgroundHeart failure is an increasing chronic disease in the western world due to an aging population and a changed lifestyle. The basic treatment is pharmacological with substantial lifestyle changes. Much is known about physical exercise in middle aged and younger patients but in the patients over the age of 65, little is known. AimThe aim of this study was to investigate the effects of physical exercise on patients aged over 65 with congestive heart failure. MethodA systematic review was undertaken in the databases Cinahl and PubMed.

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