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21 Uppsatser om Canopy - Sida 1 av 2

Modellering av reflektans från ett sockerbetsbestånd med hjälp av en strålningsmodell

The Multispectral Canopy Reflectance Model (MCRM) by Kuusk (1995) has beenused to simulate the reflectance of a sugarbeet Canopy. The simulated reflectancevalues show high absorptance in the VIS area, compared to field measurements, andhigh reflectance values in the NIR area. The errors may be due to overestimation ofclorophyll content in the sugarbeet leaves and scattered light during fieldmeasurements. The estimation of the clorophyll content where carried out using thePROSPECT-model by Jacquemoud & Baret (1990).During the vegetation period, the state of the Canopy moves towards a closed Canopy,with sparse vegetation in spring. The MCRM-model was used to perform a ?spring?simulation, which was compared to the original simulation.

Strömningen i och över en skog : utvärdering av en 'mixing-layer' hypotes

A new theory for predicting the windprofile over a Canopy has been evaluated. The theory was first presented by Harman and Finnigan (2007). The theory relies on the forming of a mixing-layer above the Canopy, due to different mean wind in and above the Canopy. Characteristics from both mixing-layer and Monin Obukhov similarity theory have been used to develop the governingequations that give the wind profile. The theory has been used to calculate wind profiles for sixdifferent atmospheric stabilities.

Alnarps rehabiliteringsskog : ett gestalningsförslag

The understanding of the role of nature for rehabilitation of both physical and psychological afflictions has greatly increased in the last few years. There?s a lot of science that describes the healing effects of nature. The rehabilitation garden in Alnarp has contributed with very positive results from the treatments of patients with burnout syndrome. In the first stages of rehabilitation, the need for calm is very important and a demand-less and stress-free environment is of essence.

Neonate mortality in fallow deer (Dama dama) in relation to bed-site selection and habitat use

The level of neonate mortality in a free ranging fallow deer (Dama dama) population at the Koberg estate in south western Sweden was investigated using radio-tracking techniques. During this study a total of 36 fawns (17 ?, 19 ?) were captured and marked with vhf or gps radio collars; 12 fawns in 2008 and 24 fawns in 2009. The neonate mortality calculated by the Kaplan-Meier method was 23.6 % and the mortality caused by predation was low, since only 1 of 8 non-surviving fawns died from predation by red fox (Vulpes vulpes). The spatial behavior of the fallow deer neonates were examined at two different levels i.e.

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.

Rehabilitation in a tropical secondary rain forest in Malaysian Borneo : early effects of canopy properties on light conditions at the forest floor

Tropisk regnskog i Sydostasien är ett av de områden som hyser störst biodiversitet i världen, av vilken stora ytor är hotat. Ön Borneo drabbades av en katastrof åren 1982-1983 efter att väderfenomenet El Niño orsakat torka med vidsträckta skogsbränder som följd. Detta lämnade stora ytor av Borneos skogar i ett undermåligt, sekundärt tillstånd. På grund av detta startades INIKEA projektet med syfte att rehabilitera skogar i regionen kring Tawau vid östkusten av delstaten Sabah i Malaysia. I denna studie undersökte jag resultatet av rehabiliteringsarbetet på krontaket i tre olika skogstyper genom att ta hemisfäriska foton med en digital systemkamera (DSLR).

Rhododendron ur undersläktet Vireya - något om dess karakteristika och användning i nordiska vinterträdgårdar :

Present essay aims to introduce the reader to central topics regarding Rhododendrons of subgenus Vireya. As a result of a donation, the Swedish University of Agricultural Sciences, received a collection of Vireya from a local amateur grower, Kurt Myllenberg. Since the subgenus Vireya is uncommon in Scandinavian horticulture, the study tries to establish conditions for successful growing. The subgenus Vireya differ from the other Rhododendron species through mainly three characteristics: the presence of two tails, attached to each end of the seed; the ovary-style junction is tapering and the pedicels arises directly from a dome-like base and form an umbel and not a raceme. The subgenus is distributed mostly in the islands of Indonesia and New Guinea, but also from Malaysia to Nepal and in Australia. Since Vireya species mainly grows as epiphytes in the tree canopies, they need high drainage and not too much water.

Stem injection of different nitrogen forms into young Norway spruce

This master thesis has been a pilot study preceding a forthcoming project of a larger scale with the long term objective to separate the direct effect of added nitrogen on soil processes from indirect effects via trees. The aim of this study has been to investigate the allocation of nitrogen following direct injection of liquid solutions into the xylem of 40 year old Norway spruce. The field site is located at Flakaliden (64°07?N, 19°27?E), approximately 60 km northwest of Umeå, Sweden. A total of 18 trees were selected for treatment, equally divided between three treatments, potassium nitrate, glutamine and water (control).

Undervegetation : användning av vedartade marktäckare i anläggning

The use of the robust and durable woody ground covers is increasing, not in the least in public places. The group includes low shrubs of different height that effectively build low, tight vegetation that covers the ground. Despite all the good qualities the knowledge about them is quite low and there are ideas about them of being dull. The woody ground covers manage to struggle against weeds effectively by competing for nourishment and water, but above all, by the Canopy of the ground covers that prevent the weeds from getting enough light. In that way the woody groundcovers can effectively compete with the annual weeds.

Leaf area index in Vittelaria Paradoxa parklands in Burkina Faso estimated by light interception and leaf sampling

Burkina Faso as well as most sub-Saharan African countries struggle with providing food for a fast growing population. The dominating farming system is agroforestry parklands. Agroforestry parklands can broadly be defined as areas where scattered trees occur on farmlands as a result of selective clearing. The presence of trees in crop fields may in the long term have a positive effect on the production of annual crops. It is commonly discussed, but not proven, that the presence of trees leads to increased groundwater recharge due to higher infiltration capacity of the soil.

Flygbildsanalys av trädskiktets status efter brand : en metodstudie

During the past years fire has been identified as an important factor for nature conservation in the forest landscape. To accurately quantify the size of a burnt area is obviously important, but also to quantify the degree of fire damage to the tree Canopy. Such data are important for assessing the conservation value, and to support planning and management of the burned area in the future. I have examined how to estimate the status of tree crowns after fire from interpretation of aerial photographs. This is possible because fire changes the structure of tree crowns and this influences the colours in aerial photographs by spectral reflection. Included in the study are four areas, three of which burned in 2005 and one in 2006.

Framtagning av en modern hammock.

Denna rapport är ett examensarbete inom maskinteknik på c-nivå (15hp). Då författaren ansåg att dagens hammockar inte utvecklats speciellt mycket sedan de blev populära i Sverige på 60-talet, valde han att ägna detta arbete åt att försöka ta fram en mer modern sådan. Projektet har huvudsakligen handlat om produktutveckling och design där mycket tid spenderats på att lösa alla de olika problem som de satta kraven på nya funktioner bidragit till. Arbetet startade med en omfattande förstudie. Därefter vidareutvecklades de olika idéer som framkom under förstudien ytterligare.

Tree species traits response to different canopy cover for 34 tree species in an enrichment planted tropical secondary rain forest in Sabah, Malaysia

Tropical rain forests only cover around six percent of the world?s land area and contain around 70 % of the world´s animals and plants. Tropical rainforests have been, and still are, negatively affected by human activities. These activities lead to forest degradation which has negative impacts on production and biodiversity. Between 1970-1980 forests in Borneo, Sabah, Malaysia, was subjected to intense logging.

Hur påverkas bentiska funktionella födogrupper av kalavverkning? : Effekt på abundans, samt återhämning, av funktionella födogrupper efter kalavverkning kring små vattendrag.

Forestry affects most of the forest-covered land in Sweden. In the landscape, the most common stream type is headwaters, which are important sites for many processes and organisms in both the terrestrial and the aquatic ecosystems. The aim of this study was to investigate how the abundance of benthic invertebrate functional feeding groups in headwater streams develops after clear-cutting and if it also is possible to detect a change in the composition of feeding groups. The study also attempts to determine what factors have an effect on temporal changes in abundance of these groups. For the study, 11 sites in northern Sweden were sampled for benthic invertebrates using a Surber-sampler, and for each site Canopy-cover and pH was obtained.

Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :

Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization. It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared. During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.

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