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751 Uppsatser om Threatened species - Sida 12 av 51
Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden
Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was
studied on 12 sites in coastal areas of northern Sweden. On each site, sample
plots were placed in adjacent Norway spruce and Scots pine stands with similar
ages in between. Basal area, tree height, Site Index, volume production,
simulated maximum mean annual increment (MAImax) and tree vitality were
compared for the two species. Average basal area at the time of measurement
was 30.4% larger for Scots pine stands than for Norway spruce stands. The
difference between the two species in basal area increment during the last 10
years was related to stand age.
Bok- och grankonkurrens i Sydsverige - markegenskaper och naturlig föryngring :
In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.
Effects of brown bear (Ursus arctos) odour on the patch choice and behaviour of different ungulate species
The return of large predators to regions where they were previously extirpated has created a need for knowledge about their effect on prey species, not only their lethal but also their behavioural or risk effects. In this study the behavioural risk effects of brown bear (Ursus arctos) were tested on fallow deer (Dama dama), roe deer (Capreolus capreolus), red deer (Cervus elaphus), moose (Alces alces) and wild boar (Sus scrofa). This was done by using
patches of fur to simulate the presence of the novel predator (brown bear), a novel nonpredator (reindeer (Rangifer tarandus) and no fur as control. These three treatments were then compared. The response variables measured were increased vigilance, decreased feeding time
and change in patch use.
Vattensork och åkersork - skadegörare i svensk fruktodling
There are two species of voles that cause damage in Swedish fruit production: the water vole (Arvicola terrestris) and the field vole (Microtus agrestis). Both species make the most damage during the winter season. The water vole makes subterranean burrows and cause serious damage by gnawing on the tree roots. The field vole seldom makes burrows and gnaws the bark at the base of the tree trunk. In recent years there have been several reports about increasing vole damage.
Environmental variables determining the occurrence of the red-listed Carbonicola anthracophila and C. myrmecina in boreal forests
The global biodiversity loss is mainly due to human activities such as an intensification of forestry. Boreal forest ecosystems in Fennoscandia are characterized by disturbances such as forest fires, storms and floods. However, industrial forestry practices suppress forest fires and change the landscape, leading to a loss of habitats and associated species. Particularly lichen species with slow adaptation abilities and a strong substrate specificity face an extinction debt in boreal forests since their substrates are long-lived but no longer created. In this study the species-substrate relationship of two red-listed forest-fire dependent lichen species Carbon-icola anthracophila and C.
Förekomst av kontaminanter i importerad fisk : en litteraturstudie
A literature review of contaminants; cadmium, methylmercury, dioxins, and PCB, for eleven different fish species (Greenland halibut, gilt headed bream, sea bass, wolffish, hoki, ocean perch, angler, Nile perch, pangasius, red snapper and tilapia) that were selected in concurrence with the National Food Administration. The result can be used by the National Food Administration to gain further knowledge about the different fish species to be able to continue to give advice to varied risk category and the public. The gilt headed bream and sea bass were the only fishes whose values for mercury exceeded the limit of 0,5 mg/kg (EU Reg. 1881/2006). In the angler, Nile perch and pangasius the mean value of mercury didn?t exceed the limit, however in some individuals the mercury content did exceed what is allowed.
Kognitionsforskning i djurhållningen: grisars kognition och dess tillämpning vid slaktsvinshållning
Pigs are often mentioned as relatively intelligent animals when compared to other nonhuman species. Despite this knowledge, the vast majority of pigs are kept under conditions that lack opportunities to satisfy their cognitive needs. Therefore, a need to evaluate the present scientific studies about pig cognition was acknowledged, in order to evaluate to what extent the knowledge is applied in the husbandry of finishing pigs. If a considerable lack of application was determined, suggestions about how to use the obtained information to improve pig welfare were also to be made.
A synthesis of the present literature was made, and it could be concluded that a considerable amount of studies had been carried out in the present area. The pigs of today appear to have the same behavioural and cognitive needs as their ancestor, the wild boar.
Sker rengöring av ögon, antenner och mun hos Odonata : Coenagrion larver med hjälp av borsten på framben och fötter?
Dragonflies are fascinating. The larvae stays larvae from a couple of weeks up to 5 years, it depends on the species (Hansen, 1981). The temperature, nourishment and time of the year also play a role for the growing factor for the larvae. Both Sahlén (1985) and Begon a.o (1990) say so. My report contains information about the branched setae on the front legs from the family damselflies (Zygoptera) and the species Coenagrion.
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.
Serum Amyloid A as a possible marker of health and disease in non-domesticated mammals : a retrospective pilot study of SAA levels in dolphins, elephants and tapirs at Kolmården Wildlife Park
The veterinary handling of wildlife, both in zoos and in the wild, commonly requires that the patients need to be captured and immobilized for examination or treatment. This emphasises the need for quick, on-site, laboratory equipment, in order to minimize the analysis time and thus the stress for the animal and also in order to increase the possibility of starting relevant treatment early on.
The aim of this pilot study was to determine whether Serum Amyloid A (SAA) could be a measured in blood samples from bottlenose dolphins (Tursiops truncatus), Asian elephants (Elephas maximus) and South American tapirs (Tapirus terrestris). SAA rises to its maximum about 24 hours after the introduction of an inflammatory agent in companion animals. This also correlates with the estimated time it takes for animals at Kolmården Wildlife Park to be examined and having blood samples collected after being observed as sick. The study also evaluated whether the Eurolyser SOLO, using a turbidometric immunoassay (TIA) developed for human diagnostics, could be used for such analysis.
This pilot study was a retrospective analysis of SAA in convenience sampled frozen serum, collected from dolphins, elephants and tapirs.
Goliatmusseron (Tricholoma matsutake) - kräver den en kontinuitet av träd? :
Modern forestry management may disadvantage some mykorrhiza forming fungi because; they are dependent on late successions and cannot survive the constantly recurring breaks in the continuity of their host tree. For this study the specie goliatmusseron (Tricholoma matsutake) was chosen to investigate this possibility. In Sweden T. matsutake is found in greatest amounts north of Örnsköldsvik on glacifluvial sandy soils in association with pine trees and reindeer lichens.
Seventy two forest stands where the specie previously had been found were studied; 62 in the northern part of Sweden and ten in the southern. Several indicators were studied to find out if these stands have had a continuity of living trees.
Inventering av vecklare i Svenska äppelodlingar
Over the last couple of years, growers, researchers, advisors and plant protection companies have noticed increasing problems with tortricids in Swedish apple orchards. Since the insecticide Gusathion (azinphosmethyl) has been banned (end of 2008; KemI 2008), a further increase of tortricid populations can be expected. In order to get a picture of species composition and population densities among the tortricids, an inventory of seven species, Adoxophyes orana, Archips podana, Archips rosana, Cydia pomonella, Hedya nubiferana, Pandemis heparana and Spilonota ocellana was made in 11 orchards in southern Sweden (Skåne) in 2008. Population densities were estimated by bud sampling (April 20-25), pheromone trapping (May 5-September 22) and assessment of fruit damage (September 9-12). In all orchards A.
Lek hos Stinkpadda (Bufo callamita): jämförelse av restaurerade och ickerestaurerade hällkar
The natterjack toad (Bufo calamita) is one of three species of toads living in Sweden. During the last decades declines in population numbers have been detected and are thought to be primarily due to loss of habitat, overgrown breeding ponds and competition from common toad (Bufo bufo) and common frog (Rana temporaria). In 2012 20 ponds in the location of Glommeskallen in Smögen were restored by clearing the ponds from overgrowth. The aim of this study was to investigate if natterjack toads used the restored ponds and if the restoration had made an impact on the natterjack population on the location. Presence of common toad and common frog was recorded, as was the presence of eggs and larvae of any of the three species.
Bräkanden från förr : att skilja får från getter utifrån kv. Apoteket 4-5 i Visby
To differentiate between bones from sheep (Ovis aries) and bones from of goats (Capra hircus) is a long lasting challenge for zoologists, archaeozoologists and osteologists. Especially considering archaeological remains which are often found fractured and poorly preserved due to taphonomic processes. Zeder & Pilaar?s (2010) and Zeder & Lapham?s (2010) methods of species differentiation has shown promising results when used on bones from modern sheeps and goats. This paper aims to evaluate these methods by exerting them on excavated bones from kv.
Ekjättars framtid : en fallstudie av gammelekar idag och i framtiden vid olika skötsel- och restaureringsscenarier i Hjulstaområdet, Enköpings kommun
This Master's thesis work was done at SLU, Uppsala, Sweden in cooperation with Upplandsstiftelsen and Uppsala County Council. The studied area is pointed out as an area for EU´s LIFE project, NATURA 2000, concerning the Scarabid beetle Osmoderma eremita. The studied area lies in an agricultural landscape rich on deciduous trees, about 15 km south of Enköping in the County of Uppland. The species is dependent on large, old, hollow trees, which are exposed to sunlight, usually oak trees in this area. I studied the area in detail concerning large old trees (>70cm ø), middle-aged oak trees and young oak trees.