Sökresultat:
52 Uppsatser om Endangered - Sida 2 av 4
Habitatpreferenser hos tjockskalig målarmussla (Unio crassus) med avseende på vattendjup och beskuggning.
The thick-shelled river mussel (Unio crassus) is a red listed species classified as Endangered (EN) and is also considered within the Habitats Directive. The distribution in Sweden is fragmented and it is mostly occurring in the south eastern parts. We investigated the presence of Unio crassus in a section of the stream Storån, Östergötland County, from Falerum to the inflow into Lake Åkervristen. The environmental parameters investigated were water depth, bottom substrate, shading, water velocity and the slope over the water surface. In this thesis I have focused mainly on water depth and shading, comparing sites with and without mussels.
Rekonditionering av IBC
This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.
Standardisering av dragarinstallation
This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.
Ett alternativt lågtrycksbränslesystem
This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.
Förutsättningar för återintroduktion av stora gräsätare i Sverige
Biodiversity is under threat in Sweden and many species are on the brink of extinction. This is mainly due to the large-scale drainage projects during the 19th and 20th century and the increasingly intensive land use in agriculture and forestry. The intensive land use with sharply defined boundaries between the production units has in many cases led to either overgrazing or overgrowing. As a result many species have been pushed back to "leftover" habitats like shooting ranges, power line corridors, roadsides, dumps, embankments and other similar areas. Therefore the question has been raised, wether or not it is needed to re-introduce large herbivores into the wild in order to maintain the biodiversity that is related to the extensive land use.This study has been conducted as a literature review and will focus on the European bison?s (Bison bonasus) impact on other species and biodiversity; conditions for reintroducing large herbivores in Sweden are also discussed.Free roaming populations of large herbivores have a positive impact on plants, insects and many other groups of organisms.
Konstruktion av instrument för dragprov på nervceller
This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.
Flodpärlmusslans status i Laxtjärnbäcken : Effekter på flodpärlmusslan av sedimentbelastning och förekomst av bäckröding
The aim of this present study was to determine and evaluate whether the presence of brooktrout (Salvelinus fontinalis) and sediment load may be a threat against the reproduction anddistribution of freshwater pearl mussel (Margaritifera margaritifera) in a creek located innorthern Sweden. Freshwater pearl mussel is an Endangered species and is dependent ofbrown trout (Salmo trutta) to reproduce. Therefore there are concerns of indirect effects onthe population of pearl mussel by competition between brown trout and brook trout. Ditchesfrom a nearby gravel road have been fixed to lower the sediment load into the creek. I tried toevaluate this action plan.
Resonans
This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.
Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?
The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.
Påverkas mosippa (Pulsatilla vernalis) negativt av igenväxning?
Pulsatilla vernalis is one of several Endangered plant species that benefit from wildfires and small scale disturbance events that repel competing vegetation and create open patches in the vegetation cover. Previous studies argue that Pulsatilla vernalis is decreasing in numbers due to vegetation changes associated with the decrease in wildfires, forest grazing and changes in forest management. In this study, 17 populations of P. vernalis were inventoried in order to examine if soil and/or vegetation structures affect the population structure of P. vernalis (i.e.
Att rädda världens djur : en retorisk analys av Parken Zoo:s kriskommunikation
Crisis communication can make a crisis turn into a double crisis. The purpose of the thesis is to analyze by which rhetorical means a double crisis can occur. With the Swedish zoo Parken Zoo as a specific example, this essay examines the crisis communication during the crises that started with the tv-show Kalla fakta. The tv-show revealed that Parken Zoo killed and slaughtered Endangered and sacred animals. When asked about the specific animals, the head of the zoo gave different answers ? which contrasted with former employees testimony.
Verktygsanvändning som miljöberikning för gulbröstad kapucin (Cebus xanthosternos)
That animals should be able to express their natural behaviours, even in captivity, has become a more important issue lately. Nowadays Zoos work much more with educating people and helping conservation projects for Endangered species. This is two important reasons for making the environment as natural as possible for zoo animals. Both in captivity and in the wild capuchin monkeys have been seen to use tools such as stones and sticks to get food and are therefore seen as a natural and important behaviour for them.
This study was carried out to evaluate a specific sort of environmental enrichment where a group of three capuchins had to use sticks to get different kinds of food out of bottles.
Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population
The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural
forests. In Sweden, it is red-listed as Endangered (EN) and an action plan for its preservation
has been done by the Swedish Environmental Protection Agency. In this work I have
therefore investigated how a translocation of the species succeeded after 17 years. I aimed
to study the species dispersal biology, its substrate preferences and the supply of suitable
wood on this site. The study was performed during 2012 in Pansaruddens nature reserve
close to Uppsala in Sweden, which is a spruce dominated forest.
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.
Zoonotic respiratory infections and great ape conservation - an emerging challenge
The conservation of great apes faces many challenges, one of which is the threat of infectious disease outbreaks. Zoonotic transmission of respiratory diseases from humans to wild great apes has recently been confirmed. Since respiratory disease is one of the major causes of
death in both gorillas and chimpanzees, this gives reason for major concern.
Little is known about the risks of disease transmission from humans to great apes in natural environments, and there is a need for systematic risk evaluation. Researchers, conservation staff and tourists spend time in very close proximity of wild great apes, sometimes during
long time periods, which poses a potential risk of disease spillover. However, the presence of researchers and tourists has been shown to decrease the risk of poaching, making the matter increasingly complex.