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92 Uppsatser om Habitats - Sida 5 av 7
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.
Död ved i ett referensvattendrag
The purpose with this study is to find out how much dead wood we can expect us to find in a Russian reference river and compare with studies from Swedish streams. Dead wood are an important structure for the biodiversity in forest streams, studies have shown that population of trout can increase with up to 300 % when the amount of dead wood are increasing from 0 to 8 ? 16 LWD (Large woody debris)/100 m2. Dead wood are also an important structure for the stream character, formations of dams and pools which are important Habitats and reproduction areas for salmon and brown trout.
The study where taken place in tributaries to the Russian river Varzuga in the North West part of Russia outside Murmansk. Varzuga has low impact of human activity and is considered to be a reference river to rivers in northern Sweden.
Sand pits as habitat for ground beetles (Carabidae) : does the area affect species number and composition?
Sand pits are a valuable habitat which can hold many sand living species including several endangered ones. As many sand Habitats with exposed sand are declining, sand pits have a potential as a substitute habitat. This study was conducted to see what effect the area of a sand pit has on species number and composition of ground beetles (Coleoptera: Carabidae). Also, the effects of other environmental variables were tested, for example the proportion open sand, vegetation cover, sun exposure and tree cover. The study was conducted in the county of Uppsala in 2008 and included 13 sand pits with areas between 200 and 180,000 m2.
Habitat use and ranging behaviour of GPS tracked juvenile golden eagles (Aquila chrysaetos)
Throughout its wide distribution in the northern hemisphere, the golden eagle occurs in a diverse range of environments, e.g., mountainous, forest and open areas. The literature on juvenile golden eagles is limited, and this study provides further knowledge on habitat use and ranging behaviour during the post-fledging period in boreal Sweden. A total of 14 golden eagle juveniles were tagged with GPS transmitters during 2010 and 2011, and nine could be followed during the entire post-fledging period from fledging until migration.
The juveniles fledged at the end of July and beginning of August and initiated migration during October and beginning of November. The length of the post-fledging period, until migration started, ranged from 49 to 97 days. During this period, the juveniles? distance from their natal nest and their GPS height increased with time as their flying abilities developed.
Rondellen och dess växtmaterial
Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned Habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.
AHA in northern Sweden ? a case study : conservation values of deciduous trees based on saproxylic insects
AHA is a Swedish abbreviation of "reveal threatened park and avenue trees" and is a method to assess the conservation value of individual trees, mainly in the park environments but also in natural stands. This method has previously only been practiced in southern Sweden (Sörensson 2008). To see if this method could provide satisfactory results in northern Sweden, I have studied it in areas around the Umeå River. This was done by studying the relationship between trees with different classifications of conservation value (as classed by the AHA method) and their content of species (species richness and abundance). Insects were collected using trunk window traps in a period of 13 weeks during the summer of 2014.
Comparison of bird communities in stands of introduced lodgepole pine and native Scots pine in Sweden
The introduced lodgepole pine (Pinus contorta) occupies more than 650 000 hectares in Sweden. There are some differences between lodgepole pine and Scots pine (Pinus sylvestris) forests which could affect bird assemblages, for example differences in canopy density and ground vegetation. Birds were surveyed in 14 localities in northern Sweden, each characterized by one middle-aged stand of lodgepole pine next to a stand of Scots pine. The two paired stands in each locality were planted by the forestry company SCA at the same time and in similar environment to evaluate the potential of lodgepole pine in Sweden. In those 14 localities, one to three point count stations were established in both the lodgepole pine and the Scots pine stand, depending on the size of the area.
GIS-baserad habitatmodell för mindre hackspett, ett verktyg för att bevara skyddsvärda lövskogar inom Umeälvlandskapet :
Deciduous forests are, according to the National Environmental Quality Objectives, a priority area. Deciduous forests are rich in species and the occurrence of dead wood is an important factor for biodiversity. In order to identify valuable deciduous forests for bio-diversity, conservation needs good analyses and planning tools. Habitat models combined with geographic information systems can be used to study the spatial structure of suitable habitat. The Lesser spotted woodpecker (Dendrocopos minor) has been proposed as an indicator species for deciduous forests, since this species is highly specialized on insect larvae in dead wood and requires large areas of deciduous-rich environments.
Many riparian forest with high species richness and high nature conservation values are found along the Ume river in Umeå municipality.
Finns det något samband mellan stormusslors (unionoida) föryngring och utsläpp i närheten av dess levnadsmiljö? : en jämförelse mellan vattendrag i Västra Götaland
Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned Habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.
Gullrisbock (Phytoecia nigricornis) i grus- och sandtäkter i Halland.
This dissertation is done as a preparatory step for the action plan of environmental protection shall issue to preserve the Phytoecia nigricornis in the country when it is red-listed and classified as vulnerable (VU). My task was to investigate the prevalence of the Phytoecia nigricornis in Halland County. They wanted to see if it existed in Halland (Ehnström, 1999). If it did not exist they wanted to know how to improve its habitat.the Phytoecia nigricornis is difficult to inventory because when it is larvae it lives in the roots and lower parts of the trunk of the Solidago Virgaurea plant and the adult beetles only keeps to Solidago Virgaurea by mating and egg laying and larval caterpillars when they hatch (Bily, 1989; Molander, 1999). Often it is overlooked or missed, and one question was whether it existed in the whole country or only in those parts where it was previously found in, Skåne, Blekinge and Östergötland (Ehnström, 1999).One problem for the Phytoecia nigricornis is that their Habitats is declining.
ALK?RR - K?LLA ELLER S?NKA F?R V?XTHUSGASERNA METAN OCH LUSTGAS? Empirisk studie av v?xthusgasutbyte i kustn?ra alk?rr p? den svenska V?stkusten.
Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon Habitats also contribute to coastal carbon sink capacity.
Förändring av grönområden i Västerås tätort det senaste seklet : Konsekvenser av att grönområden förändras
This thesis was done after a request from the county?s administrative board of Västmanland to provide the board with a better understanding of how green areas have changed within Västerås municipality over time.The purpose and goal of this study was thus to measure and analyze how much of the green areas within Västerås municipality that have disappeared during the past one hundred years as well as to provide a review of previous studies regarding the importance of green areas for humans as well as the biological diversity.In order to answer these questions I have in this study used a combination of a literature study, cartographic analysis as well as a time series analysis. The computer software used to do the measurements of the green areas was ArcGIS which is a geographical information system.In the cartographic and times series anlaysis measurements and analysis was made of the district map of 1911, the economic map of 1950 and the property map of 2011. The measurements show that the municipality has grown with 46,3 km2 over the last one hundred years. New neighborhoods? have emerged and the municipality has expanded.
Förändringar i vegetationens sammansättning efter en våtmarksrestaurering : Changes in the vegetation composition after a wetlandrestoration
The loss of such great wetlands, which has arose in Sweden the last decades, has created a situation that threats both the function and the biological diversity within the wetlands. Many ecological niches can be found in the wetlands and it is one of the Habitats where most different species exist. In the 17th Century people started to ditch damp environments, such as bogs, to create a productive cultivated ground. Further ditches were made when the forestry gave large economical profits. The wetlands were impoverished from both groundwater and nourishment, and this led to a great loss of species.In a corporation with WWF and Skogsstyrelsen in Arvika, the University of Karlstad has participated in the Laskerudproject, a hydrological restoration-project in a forest landscape.
A Green Belt of synergies : a study on the implementation of a contemporary Green Belt
The prevailing urban migration is a worldwide process. This results in growing cities and a diminishing proportion of people living in the countryside. As the urbanization continues a large amount of the world?s population is expected to live in urban settlements of informal character by 2050. Green Belt has for many years been used to control urban growth and to secure the sustention of larger green areas around towns and cities.
Habitat preference and dispersal of a sandassociated beetle, Apalus bimaculatus
Species that have a high degree of specialization and poor dispersal ability can be more prone to extinction than more generalist species and good dispersers. How these species traits affect the viability of populations is dependent on landscape factors,such as isolation and connectivity. Additionally, interactions between species (e.g. symbiosis), and how these interactions vary spatially and temporally can have a large impact on populations. When the range and habitat areas of a species continuously decrease, management strategies are often needed if the species shall be able to survive.