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377 Uppsatser om Vegetation changes - Sida 4 av 26

Kolbottnarnas påverkan på vegetationen i utmarken i västra Bergslagen

Uppsats för avläggande av filosofie kandidatexamen i Kulturvård, landskapsvårdens hantverk, 15 hp, [2015].

Vegetationslösningar och andra metoder mot stranderosion :

Today 70 percent of the world's sand beaches are under recession due to erosion. The global warming may have the effect upon the sea level increasing and the erosion increasing on the sand beaches. To save these sand beaches, the erosion must be prevented. Coast erosion shelters like gabions and sea walls are functioning extremely well to protect the land behind the sand beach, but due to the wave reflections, created in front of these so called hard erosion shelters, the erosion of the front beach is accelerated. During the last decades, artificial sand supply (beach nourishment) has been the adopted praxis.

Faktorer som påverkar Vänerns öppna sandstränder och möjligheterna för hög biologisk mångfald ? med mossor som indikatorer på igenväxning

The sandy beaches of Vänern are threatened by overgrowth and thereby the biodiversity is at high risk to decline. This study is based on an inventory of vegetation of overgrowth character and mosses. The frequency and spread of mosses is perceived as an indication of initial or present overgrowth. External factors that have been taken into consideration are wind-, wave- and ice erosion, the slope of the beach, wear and grade of exposure. The purpose of the investigation is to control the beaches grade of overgrowth and find out which external factor is of most importance for the maintenance of the biotope. The results show that the beaches environment is affected by the slope of the beach, grade of exposure, size, wear and overgrowth.

Undersöka förbättringspotential med verktyg från Lean produktion

In the year 1783 a fissure eruption from Laki in the southern part of Iceland produced a large amount of volcanic gases during a period of eight months. The volcanic gases and aerosols spread across the northern hem sphere due to ideal weather conditions and had a substantial impact on the environment, human health and also climate effects. This, so called dry fog, caused severe health problems, which led to death casualties, killing animals, crops and other vegetation. The consequence was a widespread famine which was aggravated by a hard and long winter in 1783/84. Analysis shows that the Icelandic volcanoes are the primary risk to produce dry fog that can affect Sweden.

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.

H?RNERVMOSSA I SANDSJ?BACKA NATURRESERVAT: Analys av h?rnervmossans invasivitet p? ljunghedens vegetationstyper

Heath star moss (Campylopus introflexus) is an alien species in Sweden and is currently classified as composing a "very high risk? of becoming invasive in the country according to SLU, and has in several parts of the world taken over large areas in a short time. The moss is characterized by its preference for disturbed and burned land, something that occurs on the heathland in the Sandsj?backa nature reserve, when burning for nature conservation purposes is carried out annually. Sandsj?backa's heathland is a valuable ecosystem and is one of the few heathlands in a favorable condition that remains in Sweden after strong reforms in modern agriculture in the last century, which led to forest succession of these cultural environments.

Samband mellan dammars egenskaper och trollsländearters förekomst och detekterbarhet

På senare år har intresset för trollsländor ökat. I jämförelse med andra stora och lättstuderade insekter finns dock relativt få vetenskapliga och systematiska studier. Denna studie syftar till att undersöka hur habitatet påverkar trollsländearternas förekomstmönster och detekterbarheten hos olika arters larver samt inventeringsmetodens effektivitet. Med detekterbarhet menas sannolikheten att arten upptäckts givet att den finns på lokalen. Både larver och adulta trollsländor inventerades i 14 dammar i Frihult, Sjöbo kommun i Skåne under juni-augusti 2009.

Skötsel av vägnära skog för trafiksäkerhet och naturupplevelse :

A great deal of the nature experience we get today is from travelling along our roads, which to a large extent go through the forest landscape. This makes the forest along our roads interesting to look at from a nature experience perspective. The main idea of this work is to increase the awareness of how we are affected by the forest when we travel through it and find out how the forest should be adapted to the road environment to create a pleasant nature experience as well as increase traffic safety. 0.9 % of Sweden's total forest area (equivalent to 200 000 hectares) is in close proximity to roads. Additionally, in Sweden 440 million hours are spent behind the wheel of which a great deal probably is spent on roads surrounded by forest in some form.

Vegetation och lutningars påverkan på osäkerheten hos laserdata för en ny nationell höjdmodell

Lantmäteriet har fått i uppdrag att ta fram en Ny Nationell Höjdmodell (NNH) över Sverige. Höjddata samlas in med flygburen laserskanning (FLS) och osäkerheten i höjd ligger generellt sett under 0,1 m på hårda plana ytor, dock kan osäkerheten öka avsevärt i terrängtyper med tät vegetation eller i områden med starkt sluttande terräng. Syftet med detta examensarbete är att kontrollera hur osäkerheten påverkas av olika vegetationstyper samt olika lutningsgrader. Provningen utfördes i delar av Avesta och Hedemora kommun i april 2012, där nio olika provytor kontrollerades enligt den tekniska specifikationen SIS-TS 21145:2007 ?Byggmätning ? Statistisk provning av digital terrängmodell?.

Vulkanisk svaveldimma : Risken att det drabbar Sverige

In the year 1783 a fissure eruption from Laki in the southern part of Iceland produced a large amount of volcanic gases during a period of eight months. The volcanic gases and aerosols spread across the northern hem sphere due to ideal weather conditions and had a substantial impact on the environment, human health and also climate effects. This, so called dry fog, caused severe health problems, which led to death casualties, killing animals, crops and other vegetation. The consequence was a widespread famine which was aggravated by a hard and long winter in 1783/84. Analysis shows that the Icelandic volcanoes are the primary risk to produce dry fog that can affect Sweden.

Det Gröna Torget : Omgestaltning av Ronneby Torg

Ronneby torg är beläget centralt i Ronneby stadskärna i sydöstra Blekinge. På denna plats går det att identifiera tre problem som utgör brist på människor (social hållbarhet), rumslighet (mötesplats) och vegetation (ekologisk hållbarhet). Tidigare har torgets södra del innefattat en stadspark vid namn ?Gröna Torget? medan hela torget idag utgörs av en hårdgjord yta med inslag av träd i dess kanter. Det finns ett behov från Ronneby kommun att utveckla torget som en mötesplats, då kommunen utlyst en förslagstävling av just denna anledning.

Bibaggar i Halländska grustäkter

This report is a result of a first survey of Halland?s gravel pits as an assignment from the County Administrative Board of Halland. The focus has been on Apalus bimaculatus, since the Swedish Environmental Protection Agency are creating a restoration program as it is red listed as Near Threatened. The purpose was also to get an overview of the pits since the County Administrative Board wants to continue this project. Apalus bimaculatus is easy to overlook since it is a short-lived beetle and it lives early in the spring.

Kustnära ekosystem som skydd mot naturkatastrofer : en litteraturstudie från ett riskhanteringsperspektiv

Research suggests that society's vulnerability to natural disasters along coasts could increase as a result of climate change, which is likely to lead to elevated sea levels and possibly an increase in the occurance of meteorological phenomena such as storms and tropical cyclones. Following the Indian Ocean tsunami disaster in 2004 and Hurricane Katrina in 2005, both of which received considerable media attention, empirical data has indicated that coastal vegetation might be able to protect and reduce damages to coastal communities during tsunami events and tropical cyclones.The aim of the essay has been to study the function of coastal ecosystems as protection against tsunami waves and storms from a risk management perspective, meaning that I have, through an overview of scientific articles, compiled current research on how coastal ecosystems can attenuate storm surges and tsunami waves, and analysed how this knowledge can be put into practice in coastal communities from a risk management perspective, i.e. if coastal ecosystems are a viable risk reduction measure, are practically applicable, and if so, how they could be applied.There is empirical evidence suggesting that coastal ecosystems, particularly mangroves, can reduce the strength of a tsunami wave, but full scientific consensus on this issue has not yet been reached. With regard to protection against storm surges, there is extensive scientific evidence that coastal vegetation can mitigate damages and reduce the height of a storm surge, although the wave has to traverse several kilometres inland through thick vegetation for the protection to be effective. A synthesis in the form of a figure regarding the many physical factors that influence wave development through coastal ecosystems has been created in an attempt to simplify and explain the phenomenon.The conservation and restoration of coastal ecosystems can be justified from a risk management perspective, but planting new forest belts for the purpose of disaster mitigation is quite unrealistic and can rarely be sustainable, since, for protection to be effective, the forest belt must extend several kilometres inland from the coast, and would thus likely prove difficult to implement along coastal societies..

Betydelse av lövinslag, död ved och variation i träddiameter för artrikedomen hos småfåglar

Forest management contributes to the changes in forest structure by turning heterogenous forests of varied age into homogenous forests of similar age and thus affect bird species depending on different structures or habitats which are lost during forestry. In this report, a study was made to investigate how the amount of decidious trees, dead wood and variation in tree diameter affect bird diversity. The purpose of this study was to be able to give forest management guidelines to increase bird diversity. This study was conducted by investigating 65 transects in forests of different structure south of Linköping, Sweden. Along the 65 transects, birds were inventoried as well as the vegetation.

Carbon sequestration in the pastoral area of Chepareria, western Kenya : a comparison between open-grazing, fenced pastures and maize cultivations

Carbon sequestration through restoration of degraded pastoral soils is an advocated way of mitigating global warming, and simultaneously alleviating poverty. An often proposed rehabilitation strategy is fencing of pastures, a method that was introduced to the farmers of Chepareria by the Vi-Agroforestry organization in 1987. The landscape of Chepareria changed from eroded, over-grazed grasslands, to a mixture of open-grazed commons, pastoral enclosures and cultivations. The aim of this study was to investigate (1) if the soil organic carbon (SOC) is higher inside the enclosures than on the open-grazed commons, (2) if SOC is affected by duration of fencing and (3) what effect cultivation of pastures has on the SOC. Estimations of vegetation cover and deep profile (100cm) soil sampling was performed on six clusters containing; (1) open-grazing (OG) (2) 1-5 years of fencing (FENCED(1)), (3) 7-10 years of fencing (FENCED(2)), (4) 15-23 years of fencing (FENCED(3)), (5) maize from OG (A(OG)), (6) maize from fenced pasture (A(FENCED)).

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