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912 Uppsatser om Tree species - Sida 8 av 61

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.

Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnaden i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system

In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.

Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnad i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system

In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.

Vedrötor i stadsträd : biologi, detektionsmetoder och förebyggande åtgärder

Urban trees have very little in common with trees on natural sites, such as forests or pastures. Trees in urban environments are often planted in packed soil and in small volumes. This can lead to decreased availability of water and oxygen, as well as deteriorated ability for the soil to store nutritional elements. Also above ground the tree usually have limited space in cities. Regulations on free height over roads and cycle tracks demands high stems at an early stage of their development.

36 nyanser av torsk : en osteologisk analys av fiskben från Hemmor i Dalbo i När sn på Gotland

The purpose of this paper was to analyze fishbones from the Pitted Ware Culture settlement named Hemmor. in Dalbo, När parish on Gotland. The fishbones are unburnt and derive from one specific culture layer (c:6) in trench one VI:7, and radiocarbon dated to 2600-2300 BC cal.In this paper I wanted to answer these following questions:1. What kind of fish species did they eat in Hemmor?2.

Jordlöparfaunan i bestånd av contortatall (Pinus contorta) och svensk tall (P. sylvestris) 1987 och 2010

In the 1970´s the North American lodgepole pine (Pinus contorta) was introduced to Sweden in large scale. The lodgepole pine affects its new environment different from Scots pine (P. sylvestris), leading to a change in biological diversity. Forestry today affects the ground beetle fauna (Carabidae). Habitat specialists associated with older forests are first affected. When the canopy closes again after a clear-cutting species that prefer open habitats reduces and those who prefer mature/closed forests increase. In this study we compare differences in diversity and community structure of ground beetles in stands of lodgepole pine and Scots pine.

Epiphytic lichens associated with different traffic intensities along the highway E4

Inventories of epiphytic lichens on Scots pine (Pinus sylvestris) were conducted at three sites in east central Sweden: along the newly build motorway (Road E4), along the old road (Road 600) and in a reference site, to compare the effects of traffic pollution on lichen diversities. At each site, species richness, lichen mean sensitivity value (MK), air quality index of the forest stand/sample plot (LKI) and nitrogen impact value (N) were calculated and it was tested if there was any difference between the sites. Twenty-four species were observed in total, and Parmeliopsis ambigua and Hypogymnia physodes were the most common species at all sites. At Road E4, fewer lichen species were observed than at the other sites and this might be due to the impact of air pollution. The species richness at Road 600 was similar to that of the reference site, which might be explained by the improved air quality.

Status och hotbild för den oceaniska laven broktagel Bryoria bicolor i sydvästsverige :

Horse-hair lichen Bryoria bicolor is a red-listed lichen species in the category Vulnerable. It is an oceanic lichen and it is often found on boulders and cliffs in a semi-open environment with a high humidity in the agricultural landscape. The species can also be found as an epiphyte on trees, mostly in boreal forests in the provinces of Dalarna, Härjedalen and Jämtland. In the agricultural landscape, there has been indications on that B. bicolor show a decline, and this studie aimed at examining the extent and causes of this decline.

Effektivare röjningssätt med kedjeröjsågen?

After the mandatory rules for clearing was removed in 1994, the clearing area has increased in Sweden. After the storms Gudrun and Per, the areas became planted with new plants, mainly spruce, but also other Tree species. Storm areas are now being invaded by naturally rejuvenated birch in the tilling tracks. Since the birch often is initially growing faster than the spruce it is inhibiting the growth and is also damaging the spruce. The purpose of this thesis is to study the new brush saw with chain and compare it with the conventional clearing saw, mainly in terms of performance and ergonomics. The results show that the new brush saw with chain is very good in almost all clearing operations compared to the conventional clearing saw.

Skogsbruksplanen - ett hjälpmedel i vattenförvaltningsfrågor? : en intervjustudie

After the mandatory rules for clearing was removed in 1994, the clearing area has increased in Sweden. After the storms Gudrun and Per, the areas became planted with new plants, mainly spruce, but also other Tree species. Storm areas are now being invaded by naturally rejuvenated birch in the tilling tracks. Since the birch often is initially growing faster than the spruce it is inhibiting the growth and is also damaging the spruce. The purpose of this thesis is to study the new brush saw with chain and compare it with the conventional clearing saw, mainly in terms of performance and ergonomics. The results show that the new brush saw with chain is very good in almost all clearing operations compared to the conventional clearing saw.

Artrika vägkanter - hur påverkas de av slåtter och underhållsdikning?

ABSTRACT This study is an exam work at the Department of Ecology at the Swedish Agricultural University, Ultuna, Uppsala. The field work was performed in the counties of Uppsala and Västmanland. Grassland areas, exposed to annual mowing, are known to host a variety of rare and red-listed vascular species. The area of these grassland are, however, decreasing in the landscape due to modern farming. The fact that roadside verges maintain regular mowing has proven to be a successful concept for many rare vascular plant species in this habitat. Vascular plants along roadside verges at the State road network were inventoried due to a government mandate during 1995 and 1996. As a result ?Species rich roadsides? were pointed out.

Beståndsutveckling i stormskadade granbestånd

The storm Gudrun in 2005 led to massive windthow damage in forests in southern Sweden. Since then there has been a growing interest in factors influencing wind damage in above all Norway spruce (Picea Abies) stands. Although many other interesting areas still need to be examined. In 2005 there where a lot of stands that suffered different degrees of damage, a lot of these stands weren?t cut, but instead left to grow. The future development of these stands is uncertain and the guidelines are unclear.

Modeller för brösthöjdsålder för tall och gran :

The purpose of this study was to develop two types of prediction models for Scots Pine and Norway Spruce. The first type for calculation of the stump diameter under bark the year the tree reached breast height (Dstubh130). The second type for calculation of the annual difference, e.g. the number of growth years between stump height (0.2 m) and breast height (1.3 meters above ground level). The primary thought with these prediction models is to obtain the breast height age in the trees on basis of the number of annual rings at stump.

Isolating microorganisms from marine and marine-associated samples : a targeted search for novel natural antibiotics

The search for antibiotic compounds from the natural environment has been going on for seven decades, ever since penicillin entered the market and antibiotic treatments became routine. The evolutionary pressure put on the pathogenic microorganisms induced a rapid spreading of naturally occurring resistance genes, leaving only the option of finding new antibiotics to treat the resistant pathogens. Microorganisms have been extensively mined for their biosynthetic abilities to produce biologically active compounds. To date, more than 23 000 microbial natural products have been discovered. The Actinomycetales are ubiquitous bacteria that have been used for antibiotic discovery for more than half a century, and over 10 000 natural products have been identified from the order.

Hur bokskogslagen blev till ? konflikter och lösningar 1964-1974

During the early Middle Ages beech forests (Fagus sylvatica L.) spread out over large parts of southern Sweden. They had a crucial role in human survival for hundreds of years. For various reasons, the beech forest area has decreased since the 1600s. Spruce planted on former beech forest land was the primary reason for the decline during the second half of the 1900s, which made many worried about the future of the beech forests and led to a beech forest act in 1974. This study describes the background to the beech forest act based on parliamentary official documents.

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