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703 Uppsatser om Species richness - Sida 19 av 47

Tetratermmodellering och regressionsanalyser mellan topografi, tetraterm och tillväxt hos sitkagran och lärk : en studie i norra Island

This study was made in an attempt to give the forest research centre Mógilsá a producedtetratherm map and a better understanding of how topography and temperature influencethe growth of two tree species. The digital tetratherm map model, covering the northernpart of Iceland, was developed to investigate the correlation between tetratherm and thegrowth of Picea sitchensis and Larix (sukaczewii + sibirica). The study confirms theusefulness of digital terrain models in providing data for a lot of different factors and forthe tetratherm model. Hopefully will this tetratherm map be used in future studies.Secondly, investigations were made correlating the growth of the two species againsttopographic factors representing height above sea level, distance to the sea, slope andtopex. Thirdly, investigations were made comparing the aspect and the ground shape tothe growth.The growth rate of Larix had strong significant correlations to the tetratherm and thedistance to the sea- factors.

Tillväxtreaktion på kvarlämnade träd i Hagners "Naturkultur" försök :

The primary goal of this study was to investigate how the radial growth of retained trees responds after thinning-from-above. The National Board of Forestry which initiated this study, was interested in whether there were differences in the growth-response between the tree species Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.). Another question of issue was if there were differences in the growth response between trees of different sizes. It is within the framework of the National Board of Forestry?s, Continuous Forests Project that these urgent questions are to be answered.

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.

Alnarps rehabiliteringsskog : ett gestalningsförslag

The understanding of the role of nature for rehabilitation of both physical and psychological afflictions has greatly increased in the last few years. There?s a lot of science that describes the healing effects of nature. The rehabilitation garden in Alnarp has contributed with very positive results from the treatments of patients with burnout syndrome. In the first stages of rehabilitation, the need for calm is very important and a demand-less and stress-free environment is of essence.

Fältinstruktion för skogsbruksplanering av inhemska skogar i Andinska Patagonien :

The thesis first objective was to develop field instructions for forest planning of native forests in Andean Patagonia, and the second objective was to test the plan on an actual property in the area. The thesis was limited to studies in the province of Rio Negro. Today, there are no official forest management plans for native forests in the Argentinean province of Rio Negro; thus, there is an obvious need for an official forest management plan with clear guidelines. To be granted permission to manage, i.e. through thinning, the native forests on a property it is required to have a forest management plan that is approved by the Forestry Board in the province in question (Thill, B.

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.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Nyckelbiotoper - urskogsrester eller kulturprodukter? : beståndshistorik i tolv nyckelbiotoper i Lycksele kommun

Since 1993 the Swedish Forestry Administration conducts a nation-wide inventory of wood-land key habitats covering all forest land in Sweden. The inventory aims at mapping and describing habitats where redlisted species occur or can be expected to occur. According to the inventory stand history is crucial to the presence of red-listed species. However, the current knowledge of stand history in woodland key habitats is very limited. The purpose of this work is to describe stand history in woodland key habitats, i.e. fire history, human activities - mainly cuttings - and structural changes.

Locally valued habitats, species and sites and their significance for collaborative land use planning around Manusela National Park, Central Seram Island, Moluccas, Indonesia

When new land use policies are made, opinions of stakeholders need to be taken in account, to avoid future conflicts. The motivations of commercial enterprises are often clear and easily communicated but due to inaccessibility and language barriers the indigenous people?s perspectives and needs are harder to reveal. This study therefore aims to identify species and sites of importance for the local people in Masihulan village on Seram Island, East Indonesia. This is a first step to facilitate better integration of local people´s needs into local government decision-making processes.Researchers at the Center of International Forestry Research (CIFOR), with headquarter in Indonesia, have developed an approached called ?Multidisciplinary Landscape Assessment? that aims to assess important natural resources for local communities in tropical countries.

Bokhögstubbar i Klåveröds strövområde : utbredning, egenskaper och betydelse för rödlistade vedlevande skalbaggar

Lack of dead wood is the main cause of decaying or loss of populations for many forest species. To increase the amount of dead wood is a prerequisite to maintain biodiversity in forests of northern Europe. In summer 2006 the recreation area Klåveröd, at Söderåsen in Skåne, Sweden, has been inventoried for high stumps (snags) of beech, (Fagus sylvatica). The result of the inventory has been compared with data of the real estate and forest management directories from the owner, region Skåne. The results have also been matched with the results from an inventory of saproxylic beetles in 2005, performed with windowtraps on selected snags both in the area and the adjacent national park Söderåsen. 594 snags were found on 747 ha.

Identifiering av gallringsbehov med hjälp av flygburen laserskanning :

Thinning is one of the most important silvicultural activities in middle aged forests, partly to minimize damages and partly because it leads to earlier harvesting revenues and increases the value of the remaining trees. There are many different indices used to describe stand density and thereby the need of thinning in forests today. Studies have shown that forest variables can be estimated with high accuracy using airborne laser scanning and it is likely that the method could also be used to estimate forest density indices. In this study, the possibility of using the forest density index ?H² to determine and map priorities for thinning operations for a forest area was examined.

Brandgravar : Yngre järnålder i Broe, Halla socken, på Gotland : en studie i olika metoder, med fokus på kremeringen

This essay concerns the osteological cremated skeletal remains from Broe, Halla parish, Gotland of  The Late Iron Age.The focus of this essay is to determine the position of the corpse on the pyre, whether the cremated bones were crushed after or prior to the cremation and if the individual was buried in the pyre. In addition the species, age, sex and skeletal abnormalities of the bones in question will be studied.The result of the research has yielded that the cremated bones did not need to be crushed to result in the small fragment sizes. Crushing of the bones may have happened during the cremation, this conclusion has been drawn through the comparison of a pyre experiment were bone fragmentation is evident with cremated foxes, and dogs in the cremation graves from Broe. The construction of the pyre and the position of the corpse could not be determined through colouring and fragmentation of the bones.The human's were commonly buried in the pyre, and in some cases it is possible that the "grave" in fact is the remainder of a pyre. The species found are dog, horse, cow, sheep/goat and bear.

Perfluoroalkyl substances in Arctic birds : a comparison between glaucous gulls and black guillemots from Svalbard

Perfluoroalkyl substances (PFASs) are ubiquitous in the environment today and they have been detected even in remote areas such as the Arctic. PFASs can be transported by the atmosphere and ocean currents but the transport mechanism is not fully understood. PFASs may be harmful to organisms due to their persistence in the environment, bio-accumulation potential and toxicity. Studies have shown that PFASs can cause adverse effects on the metabolism as well as the endocrine- and reproduction systems in organisms. In this study, PFASs were investigated in glaucous gull (Larus hyperboreus) (n=5) and black guillemot (Cepphus grylle) (n=4) from Svalbard.

Att beskriva upplevelsen av stadens rum :

The city is complex, multi-faceted and fascinating. The same can be said about the rooms of the city. The experience of the rooms of the city can be described in as many ways as there are individuals. The question concerned in this essay is How can you describe the rooms of the city as a phenomenon and how can you describe the experience of these rooms in general? The concepts city and room are widely understood and neither of them has a description that can be used in all situations.

Kontroll av rengöring med ATP-luminometer hos livsmedelsverksamheter med pizzaberedning i Sundbybergs kommun

This BSc thesis is a part of an initial step of a collaboration between Skansen and Kenyan Wildlife Service (KWS) and constitutes of an inventory of the Nairobi Animal Orphanage run by KWS. Animal Orphanage takes care of orphaned and injured animals arriving from throughout Kenya. The project started out as a refuge and as a temporary place for animals in need of care and help. With time it has evolved to an establishment that resembles and functions more like an animal zoo. The aim of this inventory is to focus on how the biological needs of Congo grey parrots ( Psittacus erithacus erithacus) and cheetahs (Acinonyx jubatus) are met, in terms of management and housing.

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