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751 Uppsatser om Threatened species - Sida 9 av 51
Insect communities inhabiting Inonotus radiatus growing on Alnus glutinosa trees at northern and southern shores of boreal lakes
This is a study of the insect community associated to the wood-decaying fungus Inonotus radiatus found on Alnus glutinosa trees growing in riparian forests at the northern and southern shores of boreal lakes in the province Uppland. Little is known about this particular bracket fungus and its inhabitants. Insects were reared out at the laboratory from samples of fruiting bodies of the fungus taken at five lakes. During the fieldwork in 2009, data about several environmental variables was also taken. After the rearing period, these variables and their effects over the insects were analyzed.
Increased growth in Norway spruce (Picea abies (L.) Karst.) through small annual additions of nitrogen (N) fertilizer
This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.
Interspecies embryo transfer in South American camelids : a field study
The aim of this study was to investigate the possibility of performing inter-species embryo transfer under actual field conditions in the natural habitat of South American camelids. In this study embryos from llamas were transferred to alpaca recipients. In a parallel study alpaca embryos were transferred to llama recipients. All animals used were free of uterine and ovarian abnormalities detectable by rectal palpation and /or ultrasound examination. Embryos were harvested twice after single ovulation in 10 mated female llamas and non-surgically transferred to synchronized alpaca recipients.
A literature study and survey of sycamore maple (Acer pseudoplatanus L.) in southern Sweden
Sycamore maple (Acer pseudoplatanus L.) is a common broadleaved species throughout Europe, however often
of minor interest to the forest sector. There is currently a lack of research on sycamore maple, and some of its
characteristics have throughout history contributed to a negative reputation in both literature and the forest
society. Since broadleaved species in general are of great importance to the forest sector in Europe and
presumably of enhanced significance in the future, deepened research is needed and particularly Swedish.
With a desire to hopefully increase the interest for sycamore maple, was the objective of the study to examine
the current status of the sycamore stands in southern Sweden. The study was carried out both as a survey with
inventory field work and as a literature study. Parts of the latter mentioned is also presented in the
introduction.
The study shows that the majority of the sycamore stands in Sweden are growing well, producing fairly high
qualities and volumes.
En ?terinventering och analys av den svenska populationen av svart nervmossa (Campylopus atrovirens)
Bristly swan-neck moss (Campylopus atrovirens) is in Sweden a very rare moss that only grows on a few blocks and cliffs around Gothenburg. The species can globally only be found in areas with high precipitation. Rain fall in Gothenburg has increased with a stronger greenhouse effect. Air pollution in Gothenburg has also improved. Mosses generally benefit from these conditions and this papers hypothesis is that the population of the species has grown because of these more beneficial conditions.
En studie av viltets påverkan på Skogssällskapets fastighet i Selesjö
This degree project investigates how elk, roe deer, red deer and fallow deer can affect an estate in Östergötland. The inventories performed within this project, were completed on an estate in Selesjö, northern Östergötland. This property is used to demonstrate wildlife management.
The methods used in this study were originally developed for areas larger than individual properties. Three inventories were completed in the study. These included the recording of the number of droppings and the amount of eaten pasturage, as well as the level of damage on young trees.
Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper
At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.
Gäddan & fisket i Ringsjöholm : en osteologisk metodstudie i säsong & bevarande
This paper presents the results from an osteological method study of the Ringsjöholm fishbone material. Ringsjöholm is located in Scania, southern Sweden and is 14C dated to 5960-5200 B.P. The aim of this paper is to critically analyse methods used on fish bone material in estimations of season. Three different approaches were used to estimate the fishing season at the Ringsjöholm settlement; 1) identified species, 2) size estimations of the pike based on Enghoffs (1994-95) regression formulae of os dentale, and 3) growth rings of the pike vertebrae.The identified species and the size estimations of the pike points to the fishing being active both during spring and summer. Growth rings analysis of the pike vertebrae didn?t give any quantitative results because of fragmentation.
Hotbild för ädellav Megalaria grossa i Uppland och på Gotland :
Megalaria grossa is classified as Near treatened on the Swedish Red List. It is also a so called signals spieces, e. g. a spieces that function as an indicator, signalling a forest that is worthy of protection. The aim of this study was to clarify the status at selected localities in the province of Uppland and Gotland.
Vilken effekt har lärkrutor på ogräsfloran vid ekologisk höstveteodling? :
This study forms part of the R&D project "Improved survival of bird chicks in organic fields" managed by the Rural Economy & Agricultural society in Uppsala. The skylark (Alauda arvensis) is a species that has decreased drastically in Sweden as a consequence of more intensive cropping.
Studies in England have shown that skylark reproduction can be greatly improved within
conventional fields, at a low cost, by establishing patches of bare ground (skylark plots).
Within conventional farming, herbicides can be used in case a weed problem arises due to
implementation of these skylark plots, whereas this is not allowed in organic farming. This study examined the effects of skylark plots on the weed culture in organic autumn-sown (winter) cereals and whether weeds might cause long-term problems to farmers.
The study was conducted in two parts; a field study and a review of the literature regarding the weeds observed. The field study was carried out in 2007 during three weeks in June and three weeks in July, on eleven organic fields with winter cereal in the vicinity of Uppsala.
Klövviltets nyttjande av foderraps på viltåker och betespåverkan på angränsande skog
Today we have more game species than ever before in our landscape, both regarding number of species and number of individuals. The increasing number of wild species is an increase in game recourse for the countryside. The increase of game species, however, has negative effects on forests and agriculture land. The negative effects for forestry are damages on economic important trees, due to losses in production and quality. However there are ways to decrease the damage on valuable and important trees.
Effekter av upphörd hävd i Lurö skärgård : Har diversiteten av kärlväxtarter förändrats?
One of the main reasons for the massive loss in plant species diversity is the fragmentation of habitats. In Europe, open pastures and meadows are the habitats going through the most changes during the 20th century, according to the agricultural changes. In this study vascular plants were invented at five different islands in the Lurö archipelago, Vänern, Sweden. The aim of the study was to sort out whether the diversity of plants has gone through any changes in abandoned managed grasslands compared to continuous managed grasslands. The aim was also to study if a change in the landscape has made any differences for the species development or decline.
Leder ESBL-producerande bakterier till ökade samhällskostnader i Sverige?
Due to long time of overconsumption of antibiotic, the possibility of an effective infection treatment is now threatened. Bacteria have begun develop resistant against antibiotic, witch is most due to bacteria that do not normally develop resistant. These kinds of bacteria produce ESBL, and have made the healthcare costs increase around twice as much, as for bacteria that do not produce ESBL..
Threats and opportunities for the survival of the Yangtze finless porpoise
The Yangtze finless porpoise (Neophocaena phocaenoides asiaorientalis), is a small freshwater cetacean which has recently fallen dramatically in number. It is an endemic species for the Yangtze River and unless drastic action is taken, it risks the same fate as the now functionally extinct Yangtze river dolphin (Lipotes vexillifer). Threats to the porpoise are diverse but they have in common that they are caused by man. Development of the river has been made to supply a growing human population with food, hydropower, and to reduce the risk of flooding. These changes have resulted in a degraded habitat for the porpoise.
Vad styr sortimentet hos svenska perennaodlare? : en studie baserad på sju företag i Sydsverige
The purpose of this study is to clarify the most important factors that affect Swedish perennial growers when designing their assortment. The study describes how herbaceous perennials are produced in Sweden today and try to give an answer to the question how growing method and choice of assortment are affecting the possibilities of Swedish producers to compete on the market.
Seven perennial growers in the southern and western parts of Sweden have been interviewed about their production methods and on what basis they design the assortment of perennials. During the interviews five factors seem to be the most important when the growers choose which species to grow ? profitability, the characteristics of the species, the sales channel/customer, the growing environment/growing facility and the grower?s interest and knowledge. It is often a combination of these five factors deciding if a cultivar will be grown or not.
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