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912 Uppsatser om Tree species - Sida 27 av 61

Södras gröna skogsbruksplaner ur ett landskapsperspektiv :

The aim of the "Green forest management plans" is to help forest owners to reach the environmental goal of the forestry act. But are they able to do that? Is it possible to plan preservation of species on single estates? How do single-estate-plans differ from a landscape analysis and how can the landscape approach be used in operative planning? This work was initiated to give an answer to these questions. This study was made in a landscape of 4200 ha in Östergötland county, south-eastern Sweden. A lanscape analysis was made and then compared to the Green forest management plans in the same area. The nature conservation areas (areas that were set aside to be managed with environmenatl goals) differed quite a lot between the two alternatives.

Djurparkernas tillgänglighet av information och dess innehåll: är den tillräcklig?

The purpose of zoos has changed over the decades. From being menageries where wealthy people showed their collections of exotic animals to today?s zoos where science, conservation and education has become a central part of their work. Education in zoos gives them the opportunity to spread the knowledge about ecology, biology and biodiversity to the general public. Their aim is to change the public?s attitudes towards our wildlife and raise awareness about the threats that exists against our planets biodiversity.

Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides

Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides. This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very rare and decreasing, and Norrbotten where this study was conducted.

Några vanliga ogräs : en litteraturstudie av arternas biologi samt förebyggande och direkta kontrollåtgärder

The Swedish Board of Agriculture initiated this undergraduate thesis. There is a database on their homepage that includes chemical treatments for different weed species. There is also space for preventive and mechanical control methods. This is an undergraduate thesis that reviews these control methods for the most important weeds in Sweden. The species reviewed are: Creeping perennials: Common Couch Elytrigia repens (L.) Desv. ex Nevski Creeping Thistle Cirsium arvense (L.) Scop. Perennial Sow-thistle Sonchus arvensis L. Field Horsetail Equisetum arvense L. Colt's-foot Tussilago farfara L. Stationary perennials: Dock Rumex L. Mugwort Artemisia vulgaris L. Dandelion Taraxacum F.

Smittskyddsrutiner vid flytt av djur mellan djurparker

Animals in zoos live in small enclosed areas. If a pathogen is introduced to the zoo, the animals are extremely vulnerable. The highest risk of introducing new pathogens occurs when new animals are introduced to the collection. Therefore it is essential that zoos have a protocol in place for disease prevention. This review has studied literature on the subject of disease prevention protocols when translocating animals between zoos.

Individuell tillväxt och substratval hos en lokalt differentierad population av Asellus aquaticus

Local differentiation may occur during a short period of time and is part of the formation of new species. The isopod Asellus aquaticus is an example of a species in which local adaptation has occurred during a short period of time. An establishment of stonewort (Chara spp.) vegetation in Lake Tåkern (in the 2000) resulted in two different Asellus ecotypes; a lighter pigmented, smaller one that lives among stoneworts grazing periphytic algae, and a darker, larger ecotype that feeds on decaying leaves in reed (Phragmites australis vegetation. The purpose of this study was to examine whether there are differences in growth between ecotypes, depending on whether the food was periphytic algae or leaves, and to study the choice of substrates between the two food types. For the study, animals from both habitats were brought in from Lake Tåkern to the laboratory.

Tales from under the Candy Cane Tree: Diktbok genom storytelling

Jag bestämde mig för att skapa en diktsamling för mina dikter som jag skrivit under en längre tid. Det jag vill undersöka är hur man kan använda sig av Storytelling för att skapa en helhet för en diktbok. Jag ville införa detta element i både innehållet i dikterna, vilken plats de skulle få i boken samt få in det i formgivningen. Jag tog och använde mig av litteratur för vägledning inom hur jag skulle få fram den historia som jag hade att berätta. Resultatet blev en komplett diktbok som med formgivning och placering av dikterna blev en bok som berättade en historia för sig själv i sin helhet..

Generell hänsyn vid avverkning : påverkan av dispens från sexveckorsregeln samt skogsägares kunskap, tankar och åsikter

The forests in Sweden have, for a long time, been managed intensively. This has led to even-aged stands with few Tree species and a lack of dead wood. Therefore, general conservation measures in connection with regeneration felling are important in order to promote biodiversity. Inventories carried out by the Swedish Forest Agency, however, show that about 25 % of the felled area does not reach the level of the Forestry Act, regarding general conservation measures. The aim of my study was to see whether exemptions from the six week notice of reporting regeneration fellings (the Forest Agency demands a report six weeks in advance of fellings), affect the results of the general conservation measures taken.

?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.

Utveckling av skjutdörrskoncept för hemmiljö

This report was written as a result of a Bachelor Degree Project at the School of Technology and Society at University of Skövde, first semester 2007. The assigner was Tibrokök in Tibro, Sweden. The commission was originally to design a sliding door concept for kitchen. Later it was expanded to also include bathrooms.During the feasibility study of the project Internet was used as an information source. Kitchen brochures and magazines were ordered from different companies to give inspiration and ideas.

Stamskador i gallringsbestånd

This study was conducted on a property with a thinning machine team. The purpose was to investigate in which machine, the harvester or the forwarder, that caused most damage to the trees in six different stands. Different factors, related to the damage frequency in the stands, were checked out. For example: basal area per hectare, thinning strength, tree diameter and the rate of production. The harvester drivers were also interviewed about how, when and why stem damages occur and how to minimize them. The study stated that 4.3 percent of the trees were damaged. Out of these 88 percent was caused by the harvester and the rest, 12 percent, by the forwarder..

Nipahvirus : patologi hos en nyupptäckt zoonos

Nipahvirus is most likely spread from bats to other species and causes lethal encephalitis in humans and respiratory illness in pigs. Different species are affected with varying severity but it seems to have an unprecedented zoonotic capacity and the humans affected either die or receive permanent brain damage. Full recovery is possible but very uncommon. Pigs that live and are bread in the areas that these bats frequent are constantly in danger of contracting pneumonias and meningitis and they can spread the virus further on to the people who work with the pigs and process their carcasses. These workers could then infect other humans in their immediate surroundings, their families for instance.

Virkesproduktionen under 80 år i ett fältförsök i Dalarna med olika skogsskötselsystem

I Sverige är trakthyggesbruk med kalhuggning det dominerande skötselsystemetmen intresset för kalhyggesfritt skogsbruk har ökat de senaste åren. Alternativentill kalavverkning är omdiskuterade och kritiseras ofta för att inte vara lönsamma.Målet med detta examensarbete är att analysera ett långtidsförsök med olikaskogsskötselsystem och att diskutera eventuella produktionsskillnader. De fem skötselåtgärdersom undersöktes var 1) kalavverkning med plantering av gran och tall,2) naturlig föryngring under fröträd, 3) blädningsbruk, 4) dimensionsavverkningoch 5) orörd skog (referensyta). Fältförsöket ligger på Siljansfors försökspark iDalarna och anlades 1923. Alla försöksytor har en areal av 1 ha.

Friluftslivet i det nya läraruppdraget

The aim of this essay has been to surrey the perspective of view the special education teachers have on the tree concepts of special education, compensatory-, critical and dilemma perspectiveThe questions that have been covered in this study areWhat does the concept of special education means for the special teachers? What does the concept of mathematic difficulties means for the special teachers?What does the concept of the diagnostics of dyscalculia means for the special teachers?A qualitative research method has been used to answer the questions in this essay. In the purpose to get the most out of the study..

Latitudinal patterns in body size of Roesel?s bush cricketMetrioptera roeselii within and outside the continuous area of its distribution

Over time, species colonize new areas naturally or through humans. The colonizers areoften few and founded populations represent only a fraction of the genetic diversityexisting in the original population. If the established population becomes isolated afterthe colonization event genetic diversity will remain low and if the population, in addition,remains small in size for an extended period this will lead to increased inbreeding andpossibly inbreeding depression. Metrioptera roeselii is a common species with awidespread distribution in continental Europe. During the last century, it has expanded tothe Scandinavian Peninsula which is separated from continental Europe by the Baltic Sea.My aim was to test the hypothesis that individuals in isolated populations in Scandinaviaincluding Denmark and the Baltic Sea islands are smaller than individuals in thecontinuous part of its distribution due to low genetic diversity and lacking incoming geneflow.

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