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1033 Uppsatser om Species composition - Sida 12 av 69

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.

Bibaggar i Halländska grustäkter

This report is a result of a first survey of Halland?s gravel pits as an assignment from the County Administrative Board of Halland. The focus has been on Apalus bimaculatus, since the Swedish Environmental Protection Agency are creating a restoration program as it is red listed as Near Threatened. The purpose was also to get an overview of the pits since the County Administrative Board wants to continue this project. Apalus bimaculatus is easy to overlook since it is a short-lived beetle and it lives early in the spring.

Skötselmetoder för bestånd med produktions- och naturvårdsmål :

This study is made on assignment by the local board of forestry in Skåne, Blekinge and Halland. The change of the forest law 1994 brought a new type of management plan. A more active planning was introduced in order to equate the environment goal with the production goal. The purpose with this study is to give a better picture of how planning for nature conservation in production forest is made and to develop support for selection of silviculture methods for stands with combined goals. With combined goals means production forestry with a reinforced consideration to both nature and culture, called PF-classified stands. This was done by: ? Describing silviculture models from the literature that are possible to use for stands with combined goals. ? Describing silviculture models that is used in practice in stands with combined goals. ? Describing how the classification of stands with combined goals is used. Which means, were in the terrain, with which frequency and in which type of forest PF-classification is used. ? Comparing differences and similarities of theoretical and practical used models. The study was done partly as a literature study and partly as an interview study of forest planners.

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.

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. .

Habitat diversity and composition among growing wild boar (Sus scrofa L.) populations in Sweden

The wild boar (Sus scrofa L.) has expanded across Europe and Sweden in the last decades. It is a generalist species which utilizes a variety of habitats, and its presence has been shown to have both positive and negative effects for people and the landscape they are in. The abundance and increase of wild boar has previously been shown to differ between counties in Sweden, but there have been few explanations as to why. In this study, I investigated correlations between the per capita rate of change (r) among wild boar populations in Sweden and a variety of different habitats on the county level. I also investigated if fragmentation per se or in certain habitats could be associated with the wild boar?s per capita rate of change. My results show that fragmentation/diversity per se was not correlated with wild boar r.

Indirekta effekter på marklavars abundans och diversitet vid ökad kvävehalt i marken : en jämförelse mellan opåverkad och lågintensivt brukad mark

Lichens are adapted to bright and sparse forests on oligotrophic ground. Due to a slow growth rate and high light demand lichens will suffer from competition in eutrophic environments. Therefore, lichens have disappeared from managed forests where the forest industry has increased the productivity. A reduced abundance of lichens will affect both biodiversity of the forest and the reindeer winter graze lands. It is important to understand how and for how long fertilization affects the abundance and diversity of lichens in order to protect lichen rich ecosystems. We have registered the biomass and number of lichen species in eight plots (four nitrogen rich and four nitrogen deficient) and compared fertilized Sami settlements with their oligotrophic surroundings in the nature reserves of Tjeggelvas.

Hur mycket "mjölk" ska det vara i mjölken, och hur styr vi det?

In most countries, the dairy industry focuses on the volume of milk produced instead of its composition. This results in a high content of water and a lower proportion of fat and protein. A high proportion of water is not desirable when processing the milk into various dairy products like cheese, cream and milk powder. High water content also increases the costs for transport and storage, and also an unnecessary, albeit marginal, strains on the world?s water reservoir.

Större svartbagge Upis ceramboides i norra Hälsingland : förekomst, substratkrav och effekter av skogsbrukets naturvårdsåtgärder

Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.

Thuja plicata - etableringsförsök av jättetuja med fyra olika provenienser

Future climate changes may lead to an interest of alternative and foreign forest tree species in order to spread the risks in forestry. Douglas fir, Sitka spruce, Freemont cottonwood and hybrid aspen are examples of popular foreign tree species that along with western red cedar could have a future in the Swedish forests.Södra Skogsägarna and SLU have collaboration in establishment of foreign species in Swedish forests.The purpose of this study was to analyze and present the establishment of western red cedar, and to survey and illustrate injuries of freeze drying and other damages like deer browsing, vegetation and insect attacks. The study included four different provenances, and spruce as a reference, planted in two locations ? Asa and Släne.Western red cedar is despite its name a conifer of the cupressaceae family with defined secondary characteristic and gets along well with an overstory. Western red cedar grows often in mixed stands with similar conifers and its natural habitat is within and in the area near to British Columbia.The study included two series of field inventories, one made in the summer and one in the autumn 2013, three growing seasons after plantation.

Hur ofta hälsar du på din granne? : En kvantitativ studie av integration som förklaringskraft beträffande befolkningssammansättning och radikala högerpopulistiska åsikter

A logical cause of migration is of course immigrants which is a topic always creating discussions. When arriving in a new country a process of integration with the goal to adapt to the environment is started. This study will explore the need for integration and seeks to examine the connection between population composition and radical right opinions.To fulfill the aim, a multivariate regression analysis is done on aggregated level in Sweden with statistics concerning the year of 2010. The relation between ethnic composition and voters support for the Swedish radical right party Sverigedemokraterna is studied as well as integration as an explanatory intermediate factor operationalized through unemployment, financial assistance and trust.The results of the study indicate a positive connection between immigrants from EU/EFTA and the voter support for Sverigedemokraterna. A negative relation is identified between trust and the voter support for Sverigedemokraterna.

Nyckeltal för älg och fodertillgång på tall Pinus sylvestris och rönn Sorbus aucuparia

It has been shown that moose can affect plant community composition and structure. Selective browsing with other damages of large herbivores on tree species with different tolerance to disturbance could reshape the tree layer in both managed and natural forests. Rowan Sorbus aucuparia is widely distributed throughout Sweden and Europe. Research has shown that browsing by moose may prevent rowan from reaching browsing safe heights. The goal has been formulated that, where rowan is indigenous, it should have a good competition status and be able to reach tree level.

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