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27 Uppsatser om Dispersal - Sida 2 av 2

Grodsamhällen längs vattendrag på Borneo : En identifiering av habitatkaraktärer viktiga för diversitet och abundans av grodor i tropisk regnskog

The stretch from the riparian zone of a major river, through the mouth and upstream in tributaries forms a range of differing habitats. The aim of this study was to investigate the effect of these different habitats on the riparian frog community in primary rain forest in Borneo; i.e. examine whether any gradients could be demonstrated in terms of species composition, diversity and density of frogs, as well as which environmental characteristics that seem to be of most importance in forming habitats of high conservational value. A major river, Segama, and three of its tributaries were investigated. The surveys were carried out at night by searching for frogs visually and acoustically along the streams, from the shore of the Segama river and 400 metres upstream in the tributaries.

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.

Spatt relaterad till tarsalledens vinkel

The effectiveness of Phlebiopsis gigantea to prevent spore infections from Heterobasidionannosum and Heterobasidion parviporum on hybrid larch stumps were investigated in fivestands in southern Sweden. All sites are former forest land and the age of the trees wasbetween 9 and 13 years.The study was implemented in August 2010, a month where spore Dispersal should be great.The five sites were located in previously un?thinned monocultures of hybrid larch. The sporeload in the air was studied with the help of spore traps from three different tree species;Norway spruce, Scots pine and hybrid larch. A total of 146 spore traps, evenly distributed inall five sites were analyzed.

Efficacy of Phlebiopsis gigantea treatment on spore infections of Heterobasidion spp. on Larix X eurolepis

The effectiveness of Phlebiopsis gigantea to prevent spore infections from Heterobasidionannosum and Heterobasidion parviporum on hybrid larch stumps were investigated in fivestands in southern Sweden. All sites are former forest land and the age of the trees wasbetween 9 and 13 years.The study was implemented in August 2010, a month where spore Dispersal should be great.The five sites were located in previously un?thinned monocultures of hybrid larch. The sporeload in the air was studied with the help of spore traps from three different tree species;Norway spruce, Scots pine and hybrid larch. A total of 146 spore traps, evenly distributed inall five sites were analyzed.

En inventering av säregna trädformer funna i Sverige

In Sweden and in Scandinavia the amount of tree species are rather few. However many different forms of trees arise due to mutations and gives rare appearances like cut-leaved and hanging forms. In some cases these trees are interesting as cultivars and a few of them have become popular garden trees. The knowledge of the original trees and early propagation is meagre.In this study a selected group of trees were found through search of literature. Eight tree forms were chosen and investigated in situ.

Spridning av bekämpningsmedel i banvall : Modellutveckling och känslighetsanalys

The stability of railway embankment is essential for safe transport. In order to ensure safe transport, water should be allowed to freely drain. Furthermore, as the engine driver has to be able to see signs, and people working on the embankment are supposed to easily see flaws on the rails to ensure safety for the passing trains, plants should not be allowed to grow on the embankment. In Sweden there are 12 000 kilometers of railway tracks and 25?30 % of them are treated for weed control every year.

Minskad utbredning av apollofjäril, Parnassius apollo, i södra Stockholms län : En studie av möjliga faktorer utifrån artens habitatkrav

The Apollo butterfly, Parnassius apollo, is categorized as Near Threatened (NT) in IUCN Red List. Today in Sweden it is found only in strongly fragmentized populations. In the county of Stockholm, P. apollo exists exclusively in some islands of the archipelago and with one mainland population in Stora Vika. This study has the purpose of expanding the knowledge of the local conditions for the butterfly in the south parts of the county of Stockholm and thereby contributes to a sustainable land management that can preserve the Apollo butterfly.A comparative study was done between areas where the butterfly today have: a stable population (Stora Vika, Utö and Ålö), has disappeared (Muskö and Yxlö) or is strongly declining (north part of Ornö).

Kartläggning av föroreningars förekomst och spridning i Gräsötippen enligt MIFO

It is estimated that 22 000 contaminated areas exist in Sweden today. In order to classify the risk of contaminant migration from these areas and to prioritize which of these contaminated areas should first be treated, the Swedish Environmental Protection Agency (EPA) has designed a method, for the investigation of contaminated areas (MIFO). One of these contaminated areas is the landfill Gräsötippen outside Köping. The landfill has been used by both Yara AB and the Köping municipality between the years 1945 and 1975, and both industrial and household waste have been deposited there. The aim of this report is to survey which contaminants that can be found in the soil and water in the landfill Gräsötippen and to evaluate the migration of these contaminants.

Kan en standard för miljökommunikation förbättra miljöprestanda? : Ett examensarbete i samarbete med NQA Nordic AB

Mankind has always been communicating, it is almost impossible to not communicate. The communication tree has grown a new branch, the environmental communication branch, and an ISO standard, the ISO 14 063 Environmental communication- guidelines and examples was issued October 2006. The purpose of this thesis is commissioned by the managing director of NQA Nordic AB in order to examine and analyse how organisations communicate environmental issues today, and how big the need for ISO 14 063 actually is, and further more if there are needs and wishes to make ISO 14 063 a certifiable standard. The main conclusion is that the there is a need for the standard, but it is difficult to say in which form since the knowledge about the standard is far to low among the organisations examined in this thesis. Clarity and transparency as ISO 14 063 promotes are important ingredients in organisations? environmental work, so sure a standard for environmental communication can help improve environmental performance, for example through opening up for two-way communication and from that on take part of the stakeholders? opinions.This study is based on a literature study and a questionnaire survey where 70 organisations (in this case authorities, corporations and non-governmental organisations) randomly chosen from the seven criteria, which ISO 14 001 defines as the environment: land, water, air, flora, fauna, natural resources and man and his collaboration with those.

Inventering och riskklassning av förorenade områden i Öna och Östnor :

This work consists of a survey and risk classification of eleven metal industries including foundries, finishers and engineering industries in two industrial areas in Mora. The study follows a method called MIFO (Method of Surveying Contaminated Sites) composed by the Swedish Environmental Protection Agency. In the method assessments of the degree of hazard posed by the pollutants, the level of pollution, the conditions of Dispersal, sensitivity and the degree to which the area is worthy to protect are made for each contaminated site (object). The assessment classify the objects into four risk classes in which risk class 1 denotes a very large risk, 2 large risk, 3 moderate risk and risk class 4 little risk. The work of surveying using MIFO is divided into two phases.

Landskapsplanering och konnektivitetsförbättringar inom värdetrakter i Västerbottens län :

According to the Swedish strategy for forest protection, additionally 40 000 ha productive forestland will be protected in the county of Västerbotten, between 1999 and 2010. A national project was carried out to distinguish the proportion of forest with a high biological value, in all counties. The project resulted in demarcation of small landscape areas or small ?biological value regions? (bvr), with higher concentrations of forests with conservation values and red listed species than the surroundings. In Västerbotten, 26 such bvr?s were identified and the Counties Agency and Forest Agency in Västerbotten developed a regional strategy for forest conservation to standardize the forest protection process.

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.

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