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Forest characterization with high resolution satellite data for a regional inventoryKelly, Tabatha Rae 02 May 2009 (has links)
QuickBird satellite data was used to examine stem density, basal area, and crown density, as potential forest strata to aid in volume estimations for a regional inventory program. The classes used for analysis were pine pole and sawtimber, and hardwood pole and sawtimber. Total height, height to live crown, diameter at breast height (dbh), and crown class were measured on 129 field plots used in image classification and accuracy assessments. Supervised classification produced overall accuracy of 85% with a Kappa of 0.8065. The classification was used for the extraction of mean band data and percent of forested pixels. Satellite derived variables were used with field measurements such as average basal area and stem density for regression analysis to predict forest characteristics such as stem density and crown closure that are indicators of volume variability. The R2 values ranged from 0.0005 to 0.2815 for hardwoods and 0.0001 to 0.6174 for pines.
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Effects of stand type on ground lichen height and species richness in boreal forests : P. contorta as an alternative to P. sylvestris in providing a suitable habitat / Ståndortsegenskaper som påverkar marklavars höjd och artrikedom i boreala skogar : P. contorta som ett alternativ till P. sylvestris i att bidra till ett lämpligt habitatJohansson, Maria January 2015 (has links)
Effects of stand type on ground lichen height and species richness in boreal forests. P. contorta as an alternative to P. sylvestris in terms of providing a suitable habitat Maria Johansson Abstract Lichen-rich forests are essential to reindeer but up to 50 % of the lichen-rich areas in Sweden have been lost since the 1950s. Ground lichens thrive in pine-heaths and with an increasing area of plantations of the non-native tree species Pinus contorta, as an alternative to the native P. sylvestris, it is important to investigate if P. contorta can provide such an optimal habitat to ground lichens. The purpose of this study was to assess if forest characteristics, such as tree density, canopy cover and production capacity, affect the abundance and growth of five lichen species (Cladonia rangiferina, C. arbuscula/mitis, C. stygia, C. stellaris and Cetraria islandica) and whether these characteristics differ between forests dominated by P. contorta and forests dominated by P. sylvestris. Fieldwork was conducted in Norrbotten and Västerbotten on sample plots previously used by the Swedish National Forest Inventory (SNFI). The statistical analysis was based on data collected from 22 sample plots, 11 of each forest type, visited during July and September 2015. No statistical significant differences were found between forest characteristics of the two forest types, and none of the forest characteristics were found to relate to lichen height. Forest age did not seem to have an effect on ground lichens, while both canopy cover and production capacity were found to negatively relate to the proxy for lichen biomass as well as the abundance of the most common lichen species, C. rangiferina and C. arbuscula/mitis. The result suggests that a shadier canopy as well as a higher production capacity contributes to a reduced distribution of ground lichens. Keywords: Ground lichens, Pinus contorta, Pinus sylvestris, forest characteristics, forestry, reindeer husbandry
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Vývoj početnosti lesních ptáků v České republice / Population trends of forest birds in CzechiaSzarvas, Filip January 2021 (has links)
Currently, most scientific attention focused on bird population trends is centred on birds in the agricultural landscape. Forest bird research, on the other hand, is given far less space, despite the fact that forests in Europe often form a substantial part of the landscape in some parts. Moreover, it is undergoing drastic changes throughout Europe, and especially in the Czech Republic. In the second half of the 20th century, their quality deteriorated due to air pollution, later regenerated, but other additional challenges have emerged, such as global climate change and epidemics of wood-destroying insects. It is therefore possible to assume their fundamental influence on forest bird populations. However, most of the work examining the effects of the forest environment and forest management on bird populations is only very local, limited to ecologically valuable, and therefore quite specific, habitats, or covering only a small number of bird species. However, data on the evolution of forest birds vary across Europe. In Finland, for example, forest birds are declining, while in neighbouring Sweden the trend is the opposite. In this study, I aim to better map what characteristics of forests affect specific species of birds, in research conducted throughout the Czech Republic. I decided to explore...
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