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315 Uppsatser om Habitat preference - Sida 17 av 21

Artrika vägkanter - hur påverkas de av slåtter och underhållsdikning?

ABSTRACT This study is an exam work at the Department of Ecology at the Swedish Agricultural University, Ultuna, Uppsala. The field work was performed in the counties of Uppsala and Västmanland. Grassland areas, exposed to annual mowing, are known to host a variety of rare and red-listed vascular species. The area of these grassland are, however, decreasing in the landscape due to modern farming. The fact that roadside verges maintain regular mowing has proven to be a successful concept for many rare vascular plant species in this habitat. Vascular plants along roadside verges at the State road network were inventoried due to a government mandate during 1995 and 1996. As a result ?Species rich roadsides? were pointed out.

Biodiversitet av evertebrater på vegetativa tak

In a city sometimes conflicts arise between either to save the species-rich vacant lots where many species thrive, or to build new buildings. Green roofs can then serve as a refuge for plants and animals that have had their natural habitat destroyed or diminished. Today we know too little about green roofs contribution to the biodiversity in the cities. We also know very little about how various types of vegetation on roof can increase biodiversity and its ability to attract different species.The aim with this study was to examine how different types of vegetation on the roofs affect the biodiversity of the invertebrate and how species-composition and number of individuals differ between the roof- and groundlevel.This study has been carried out on Augustenborg Botanical Roof Gardens in Malmo, and in an area about 1.5 kilometers away from Augustenborg. Three different types of vegetation on the roof and ground floor were selected: sedum- ruderal and grass.

Deadwood in piles or distributed : does it make any difference to saproxylic beetles?

Piles of deadwood are often retained in forests after management to support the biodiversity ofsaproxylic organisms which depend on deadwood to survive. Any knowledge about the crucial role ofpiles as suitable habitat of saproxylic organisms compared to single distributed deadwood objects thatare around the piles would help conservation actors to motivate more forest owners to supportsaproxylic organisms during their management. Therefore to give facts to this the saproxylic fauna ofdifferent pile positions (up and low) was studied and compared to distributed deadwood samplesaround each pile. Our study was focused on saproxylic beetles. Some other parameters such asdiameter, deadwood volume, pile volume and decay stage were assessed to define any effect.

Inuti den svarta lådan: En studie av beslutsprocesserna bakom EU:s gemensamma handelspolitik

Trade was assigned as a Community responsibility at the founding of the European Community in 1957. It was then recognized that Europe would achieve a greater international influence if it were to negotiate trade deals with one voice. Since then, the basic rule has been that the European Commission negotiates agreements on behalf of the EC, and presents the agreements negotiated for approval in the European Council. Today, the 25-member European Union is the largest trading power in the world, and most member states have decades of experience of coordinating their national trade interests into a common position. However, partly as a result of the complex nature of the trade decision-making processes it is sometimes problematic to identify who or what really influences EU trade policy.

Tickor på död ved

I dag råder det brist på död ved i Sveriges skogar. Detta på grund av det intensiva skogsbruket där man kalhugger och plockar bort all liggande ved. Dock är det viktigt med många döda träd i olika nedbrytningsstadier för många skogslevande arter. Svenska skogar har få urskogar där naturliga avdödningsprocesser av träd får ske och därför minskar den biologiska mångfalden i skogen. Tre arter som endast trivs i naturskog är tickorna ullticka, Phellinus ferrugineofuscus, gränsticka, Phellinus nigrolimitatus och vedticka, Phellinus viticola.

Utvärdering av Naturvårdsverkets bedömningsgrunder för makrofyter i sjöar

According to the Water Framework Directive of the European Union, macrophytes should be used as indicators in the ecological and environmental monitoring of lakes. In the member state Sweden the Environmental Protection Agency has elaborated assessment criteria for determining lake status based on macrophytes. The main focus of this thesis is to evaluate the efficiency of the assessment criteria for macrophytes. In addition the concordance between the ecological status classes of the four quality factors included was analysed.The assessment criteria for macrophytes are based on the total phosphorus preference of the respective species. The focus is thus mainly on the nutrient level of the investigated lakes and the environmental problem monitored is eutrophication.

Välfärd hos växande nötkreatur ? finns den?

During an investigation of animal welfare in animal production, the focus has for a long time been focused on the absence of stress, suffering and injuries, and positive emotions have not been prioritized. However, in recent years that has been drastically changed. The public interest have increased for buying animal products from animals that have had a decent life, which have led to that play, exploratory behavior and other positive behaviours has come to play a significant role in welfare assessment. The welfare of cattle is difficult to assess since there is currently no ancestors to study, it is thus difficult to determine which behaviors can be regarded as natural and thus positively related, acordingly the welfare of cattle have been forgotten and research on positive emotions of cattle have not been prioritized. The aim of this study was to observe which behavior growing cattle performe, and if there was any differences of which kind of behavior that was observed, if the cattle is keept on slatted floor or on a deep straw bedding. Furthermore, antoher purpose was to investigate if the observed behaviours indicate a positive, negative or natural welfare, and if it is possible to use the observed behaviours in a welfare assessment.

Svenska investerares risktolerans : En studie om risktolerans och påverkande faktorer

The Swedish household?s savings has increased the last couple of years, according to Statistiska centralbyrån. But the amount of households that trades on the stock market has decreased from the year 2012 to 2013. The diminished interest in stock trading carries a risk by leading to a smaller yield for the private savers, and also effect the business development and the economic growth. High brokerage fees will aggravate the ability to attract venture capital.

Påverkan på stormusslors (Unionoida) miljö som kan motverka livskraftiga bestånd : En studie över redoxförhållanden och kantzoners sammansättning i fyra vattensystem i Västra Götalands län

Sötvattensmusslor har en viktig roll i akvatiska ekosystem och de anses vara en av de mest sårbara och hotade organismgrupperna i sötvatten. Sverige har nio arter stormusslor, varav fyra är upptagna på den svenska rödlistan. Flest studier har gjorts på flodpärlmusslor (Margaritifera margaritifera) och hoten som den står inför. Undersökningar av de vanligare förekommande arterna i Västra Götalands län, har visat att även allmän dammussla (Anodonta anatina) och spetsig målarmussla (Unio tumidus) har problem med livskraftiga bestånd och föryngring. Stormusslor anses vara som mest sårbara när de som juvenila ligger nedgrävda i sedimenten.Den här studien har mätt kvaliteten av sedimenten i tolv mussellokaler i Västra Götalands län.

Träd och buskar i kantzoner : en undersökning av kanteffekter i några av östersjöregionens skogar

Around the world, forests are generally being fragmented and as plant populations decline in both sizeand number of individuals, the genetic variation will also decrease whitch in the end leads to totalextinction of the plant. In this paper, I wanted to investigate what specific species of trees and shrubsyou usually find in the edge and core habitats in some of the forests in the Baltic Sea region. I alsowanted to identify the edge effects and their sources and finally compare the results between thedifferent regions.The data sources used are derived from the ongoining research project Landscape structures, patterns ofbiodiversity and conservation strategies in the Baltic Sea region by Kari Lehtilä, Patrik Dinnétz ochTiina Vinter who have made a record of all herbaceous plant species in four randomly chosen forestregions situated around the Baltic Sea: Estonia, Skåne, Södermanland and Germany. I made statisticalanalyses, using the computer program R, concerning the distribution of species in the edge habitats ofthe forests as well as in the core habitats. I performed generalized linear models and then variationanalyses with the factors light and biomass in order to investigate wether edge effects might appear dueto these factors.

Utfodring av sällskapskanin. Vilka råd ger vi djurägarna?

The most suitable method to answer the issues of this study was to do a combined literature- and questionnaire study. The literature part of the study was based on Original Research articles, Review Articles and books with a list of reference literature after each chapter and the purpose was to answer the questions ?What feed items should be given to rabbits in different life stages? and ?Which problems may develop from an inadequate diet?? Two questionnaires were constructed. One was sent by e-mail to small animal veterinary hospitals to be answered anonymously by veterinary nurses. The other was linked to from two internet forums, that with rabbits as their focus.

Naturvärdesbedömning av naturreservatet Blänkabacken, i Örebro kommun : Inventering av signalarter med fokus på mossor och lavar som indikerar höga naturvärden i skogsmiljöer.

I dag råder det brist på död ved i Sveriges skogar. Detta på grund av det intensiva skogsbruket där man kalhugger och plockar bort all liggande ved. Dock är det viktigt med många döda träd i olika nedbrytningsstadier för många skogslevande arter. Svenska skogar har få urskogar där naturliga avdödningsprocesser av träd får ske och därför minskar den biologiska mångfalden i skogen. Tre arter som endast trivs i naturskog är tickorna ullticka, Phellinus ferrugineofuscus, gränsticka, Phellinus nigrolimitatus och vedticka, Phellinus viticola.

Problem med att hålla snöleopard (Panthera uncia) i fångenskap

I Centralasien lever det utrotningshotade djuret snöleopard (Panthera uncia). Antalet vilda snöleoparder beräknas ligga under 7000 individer. Snöleoparden brottas med ett antal olika hot i det vilda, med risk att det leder till utrotning. Djuret jagas av tjuvjägare, delvis för sin fina päls, men också för att använda ben och tänder till medicin. Människans utbredning leder till mindre områden för snöleoparden att hitta byten på, samt att den dödas i vedergällning om den skulle anfalla boskapsdjur.

In search for sustainable alternatives to lawns : connecting research and landscape design

A large part of Sweden?s green, urban landscape is covered by lawns. Approximately 80 000 ha of maintained grass lawns are part of public courtyards, schoolyards, parks, golf courses, sport fields and traffic environments. Beyond this figure, the lawn is also an essential element in most private villa-gardens. Lawns have become a universal phenomenon through the dispersion of landscape aesthetics from the Western world.

Mellan lag och verklighet. En studie av svenska kustkommuners f?rvaltning av grunda mjukbottnar i kustzonen.

Grunda mjukbottnar i Sveriges kustvatten utg?r biologiskt v?rdefulla milj?er med funktioner som n?ringsoms?ttning, erosionsskydd och viktiga livsmilj?er f?r fisk. Trots detta ?r dessa habitat kraftigt hotade av ?kad exploatering kopplad till bebyggelse, turism och infrastruktur. Studien syftar till att unders?ka hur svenska kustkommuner hanterar skyddet av grunda mjukbottnar i f?rh?llande till befintlig lagstiftning och nationella riktlinjer.

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