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1038 Uppsatser om Signal species - Sida 12 av 70

Thuja plicata - etableringsförsök av jättetuja med fyra olika provenienser

Future climate changes may lead to an interest of alternative and foreign forest tree species in order to spread the risks in forestry. Douglas fir, Sitka spruce, Freemont cottonwood and hybrid aspen are examples of popular foreign tree species that along with western red cedar could have a future in the Swedish forests.Södra Skogsägarna and SLU have collaboration in establishment of foreign species in Swedish forests.The purpose of this study was to analyze and present the establishment of western red cedar, and to survey and illustrate injuries of freeze drying and other damages like deer browsing, vegetation and insect attacks. The study included four different provenances, and spruce as a reference, planted in two locations ? Asa and Släne.Western red cedar is despite its name a conifer of the cupressaceae family with defined secondary characteristic and gets along well with an overstory. Western red cedar grows often in mixed stands with similar conifers and its natural habitat is within and in the area near to British Columbia.The study included two series of field inventories, one made in the summer and one in the autumn 2013, three growing seasons after plantation.

Automatisk mätning och detektering av röjande signaler

This master thesis has been performed at Sectra Communications AB in Linköping where they manufacture electronic encryption devices. In cryptology it is essential that an eavesdropper cannot find the plain text. To assure that a system is safe, all devices are thoroughly examined so that they don?t emit any secret information, so called Compromising Emanations (CE). This is done by comparing the secret signal with measured signals on the screen of an oscilloscope, a process that is very time consuming and furthermore, the risk of missing compromising emanations is high.

Inokulering med två hjorttryfflar på arginingödslade täckrotsplantor i Gideå plantskola :

The effect of inoculation on containerized pine and spruce seedlings in a nursery with two ectomycorrhizal fungi was investigated in regard to the development of mycorrhiza and plant growth. The fungi were Elaphomyces muricatus and Elaphomyces granulates and the inoculated seedlings were compared to an uninoculated control. These seedlings were all fertilized with arginine. Five mycorrhiza species were found after DNA sequencing of the mycorrhizal root tips with different found morphotypes on seedlings from all treatments. Thelephora terrestris was the type which had the greatest distribution on pine seedlings and Tylospora asterophora was found at big extent on spruce seedlings. The inoculated species was not found, if it was due to the species hadn?t colonized the roots or if the DNA sequencing failed we can only speculate about.

Naturvärden i en värmländsk bruksskog : en skogshistorisk studie av Åbengtshöjden/Bogranghöjden

In this study I have analysed the history of a forest belonging to Saxåhyttan in Värmland. The study area is 448 hectares and has been used by iron industry since the 16th century. A forest that has been used by man during at least 400 years should have few ecological values. This inventory however shows the opposite. The aim of the study is to interpret the history of the forest in the area, i. e.

Två år efter restaurering:Vad har förändrats i bottenfaunan?

The aim of the study was to examine if the benthos in a restored portion of a small lowland stream south of Linkoping differed from two non restored reference areas two years after restoration. The reference areas were one stretch downstream and one upstream stretches of the restored stream. The benthic invertebrates were collected using standardized kick sampling. In order to classify the communities and estimate any differences, three different indices were exercised. In addition rank-abundance curves and checklists were used to get a picture of species composition.

Nyttan av kurserna på naturbruksprogrammets djurvårdsinriktning

The aim of this study is to find out if the former students think that they have made use of the courses they have taken at the Natural Resource Use Programme specialised in Animal Husbandry at Lillerudsgymnasiet or if the courses should be exchanged. In the study it is assumed that a course can be useful professionally, for further studies and in private life.The main questions are: Have the former students made use of the courses they took at the Natural Resource Use Programme specialised in Animal Husbandry at Lillerudsgymnasiet? Was it the right decision to replace the course Horses?I have sent a questionnaire to all the students who graduated between 2003 and 2007. Out of 107 questionnaires I received 66 replies (62 %). All students have studied the same mandatory courses but different eligible courses.

Konstruktion av datainsamlingskort för mätsystemet COMET

During test flights SAAB uses the data acquisition system COMET 16. The part of the system that receives the signals from the sensors and converts them is called KSM 15. The purpose of this thesis is to develop a data acquisition module on stacked PC/104 modules with a lower production cost. Our work has been divided into one part about analog signal conditioning and a second part with digital filtering and memory management of the sampled data. The analog part, designed of regular components like instrument amplifiers, voltage references, operational amplifiers and multiplexers, adjusts the sensors signal levels for the ADC?s that converts the signals.

Epixylic lichens and bryophytes in young managed forests : substrate preferences and amounts of dead wood

Dead wood is important for many species. The amount of coarse dead wood (diameter >10 cm) is much lower in managed forest than in unmanaged forests. Stumps constitute the largest proportion of the volume of coarse dead wood in managed forests. Since stump harvest for biofuel may increase, the amount of dead wood will decrease even more, which may threaten biodiversity. The first aim of this study was to compare the amounts of fine woody debris (FWD, .

Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen

Climate on earth is getting warmer, which effects earth?s energy balance and so forth the ocean and atmospheric circulation.  In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations.

The welfare of bottlenose dolphins and killer whales in captivity

The aim of this paper was to investigate whether or not it is possible to keep bottlenose dolphins and killer whales in captivity while maintaining good animal welfare. Today, many zoos and aquariums claim that their primary function is to conserve species and educate people about conservation and threatened species. The keeping of wild animals is justified by conservation programs and by the information spread to the zoo visitors. This does however not seem to be the case for marine mammals such as bottlenose dolphins (Tursiops sp.) and killer whales (Oricnus orca) since these species are not threatened in the wild and neither of them are listed as threatened in IUCN's Red List. Bottlenose dolphins and killer whales are entirely aquatic carnivores and are distributed in all coastal and pelagic waters from the Arctic ice in the north to the Antarctic ice in the south.

Viltets inverkan på vegetationsutvecklingen i en Sydsvensk skogsföryngring :

Herbivore impact on the Swedish forest has under a long time been a common subject of debate. There are many different opinions depending on what direction the forest owner has with his/her forest. Populations of moose and roe deer have increased significantly in Sweden during the last decades. The purpose of this study is to get a full picture of the herbivore impact on the regeneration areas. The field work was done once a year for seven years (1999?2005).

Ternära koder för variabelt felskydd

Ternary codes for unequal error protection is a part of a communication system where different parts of the information to be transmitted can receive different amount of error protection. There are a lot of applications where the channel conditions fluctuate so that reliable or acceptable communication can not be guaranteed. Regardless whether the fluctuations of the channel are intentional or not the idea is to let the coderate decrease so that the error correcting capability can increase for the part of the information to be more protected. By using the support, the nonzero positions of the ternary code, a new binary code can be extracted with properties different from the ternary code in the sense of cardinality and minimum Hamming distance. When the channel conditions are good the receiver decodes the message using ternary decisions and receives all information included in the codeword.

DYNAMIKEN OCH EFFEKTEN AV MARINA V?RMEB?LJOR P? TROPISKA KORALLER (SCLERACTINIA)

Marine heatwaves (MHW) have become increasingly common in recent decades due to greenhouse gas emissions that have caused climate change. A marine heatwave is when the sea surface temperature rises, which damage many different ecosystems in the sea. One ecosystem that is sensitive to temperature changes is tropical coral reefs, which are at risk of bleaching during marine heatwaves. Coral bleaching is when its symbionts leave the coral and they lose their color, while also starving to death as they lose their food source. The purpose of this report was therefore to investigate what the connection between marine heatwaves and coral bleaching looks like, and to see if there are any geographical differences.

Vandring av vårlekande fisk och jämförelse av fångst mellan ryssja och strömöversiktsnät i Hammerstaån, Stockholms län

During the last two hundred years many wetlands and streams in Sweden have been lowered to provide land for agriculture and forestry. Some of the coastal wetlands and streams probably served as spawning sites for certain species of fish in the Baltic Sea, but the present situation is not well known. As standardized methods to monitor fish in running waters are carried out during late summer or autumn, there is a need for methods to sample spring-spawning fish in these streams.The aim of this study was to survey the lower kilometer stretch of Hammerstaån in Stockholm, to investigate the extent to which the stream is used by spring-spawning fish. Furthermore, the study aims to evaluate a new type of survey fishing gill net called strömöversiktsnät (SÖN). This was done by comparing the catch of fish by SÖN with that of fyke nets.

Stubbehandling med pergamentsvamp och urea mot sporinfektioner av rotticka i bestånd av hybridlärk

Root rot is a big hurter and a huge economic problem for the Swedish and European forestry. The severest hurter is Heterobasidion annosum (Fr.) Bref and it occurs as two different species in Sweden. Commonly referred to as the P-type (Heterobasidion annosum s.s. (Fr.) Bref.) and the S-type (Heterobasidion parviporum Niemelä & Korhonen). Therefore a lot of research has been carried out in this topic to find a solution and reduce this problem, one alternative that have shown to be profitable is stump treatment in thinnings.

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