Search results for "forest"
showing 10 items of 3780 documents
Vegetation and firewood uses in the western Catalan plain from Neolithic to the Middle Age
2011
In this study is presented the synthesis of the results of the anthracological analysis in the western Catalan plain from the Neolithic to the Middle Ages. The data is evaluated in order to provide a preliminary approximation on the development of vegetation and forest exploitation. S. Vila is funded by a FI-DGR 2010 scholarship,granted by the Generalitat de Catalunya (AGAUR), in the framework of the projects HAR2008-05256, and SGR2009-198.
Development of a Model to Estimate the Risk of Emission of Greenhouse Gases from Forest Fires
2022
27 Pág.
Forest fires in the Portuguese northwest
2011
Fundação para a Ciência e a Tecnologia (FCT)
Effects of stump removal on soil decomposer communities in undisturbed patches of the forest floor
2011
Abstract Soil preparation after clear-cutting leads to fragmentation of forest floor and, consequently, changes the habitat of decomposers. Stump removal for bioenergy is further increasing the disturbance in the soil. We studied responses of decomposers to stump removal in boreal spruce forests during the first 4 years after clear felling in relation to mounding. Samples for each decomposer organism group were taken from undisturbed forest floor patches that are the main habitat for decomposers after forest regeneration and whose amount and size obviously differ between the treatments. Microbial biomasses and community structure, and the abundance of enchytraeids, were not found to be affe…
Dead-wood effects on enchytraeids and nematodes in thinned and unmanaged Norway spruce forests
2009
Abstract The effects of dead wood on enchytraeids and nematodes were studied in thinned and uncut Norway spruce forests in two experiments. Fifteen pairs of small spruce logs (one enclosed in polyethylene sheet and another untreated control) were returned to the forest floor in a complete randomized block design after thinning. Soil under the logs and at distances of 0–6 cm and 6–12 cm from each log was sampled after one growing season, and enchytraeids and nematodes were extracted and forest floor properties measured. Log enclosure increased enchytraeid length irrespective of the distance from the log. Soil moisture or pH were not affected by enclosure, but organic matter content was reduc…
Direct measurement of NO<sub>3</sub> radical reactivity in a boreal forest
2018
Abstract. We present the first direct measurements of NO3 reactivity (or inverse lifetime, s−1) in the Finnish boreal forest. The data were obtained during the IBAIRN campaign (Influence of Biosphere-Atmosphere Interactions on the Reactive Nitrogen budget) which took place in Hyytiälä, Finland during the summer/autumn transition in September 2016. The NO3 reactivity was generally very high with a maximum value of 0.94 s−1 and displayed a strong diel variation with a campaign-averaged nighttime mean value of 0.11 s−1 compared to a daytime value of 0.04 s−1. The highest nighttime NO3 reactivity was accompanied by major depletion of canopy level ozone and was associated with strong temperature…
Distribution of soil animals in patchily contaminated soil
1996
Abstract Distribution of soil animals with respect to patchy chemical contamination was studied in microcosms containing reconstituted coniferous forest floor. Soil materials were defaunated and soil organisms were reinoculated into a mesh basket in the centre of each microcosm. Part of the humus layer was contaminated with three concentrations of sodiumpentachlorophenate (0, 50 or 500 mg PCP kg −1 of dry humus) and put into mesh baskets (two per concentration) around the central patch. No differences in dispersion ability from the reinoculated patch were found between microarthropod species. PCP decreased microbial biomass in the humus. Numbers of collembolans were significantly lower in t…
Evaluation of different similarity indices as measures of succession in arthropod communities of the forest floor after clear-cutting.
1979
Communities of spiders (Araneae) and beetles (Coleoptera) living in the soil and litter of clear-cut areas were compared with those of intact forest stands. Sixteen different indices of similarity were tested on three sets of material: spiders and beetles examined during one year in three clear-cut areas felled 3, 6 and 9 years earlier, and spiders in one clear-cut area examined during 7 successive years after felling. Other sources of evidence showed that succession in the spider community was divergent for at least 7 years after felling. The indices that seemed to express the changes best were: (1) Kendall's rank correlation test, (2) the Bray-Curtis measure, (3) Renkonen's percentage sim…
Oribatid mites (Acari: Oribatida) in boreal forest floor and decaying wood
2008
Summary We studied the oribatid mite communities in forest floor and in decaying wood in pine (Pinus sylvestris), spruce (Picea abies) and deciduous (mainly Betula pendula and B. pubescens) forests at different latitudes in Finland. The study sites were either in mature managed forests or in old-growth forests in nature reserves. Altogether 78 sites were sampled in 2004 and 2005, yielding a total of 38,145 oribatid mites belonging to 133 species, of which four were new to Finland. Oribatid mite communities differed in terms of total number and community structure between forest types and latitudes within the boreal forest zone. The most abundant and diverse communities were in spruce forest…
Sensitivity of soil processes in northern forest soils: are management practices a threat?
2000
Abstract There is evidence that forest management practices influence soil-decomposer communities. It is also established that changes in the trophic structure and composition of these communities can induce changes in soil-nutrient dynamics, thereby affecting plant growth. Whether forest productivity is affected by management-induced changes in, e.g. soil faunal structure, is, however, yet to be shown. The aim of this study was (1) to determine the resolution of the ecological hierarchy (e.g. species, functional groups, trophic levels) at which a change in soil fauna would alter biotically-controlled processes in soils, and (2) to examine the sensitivity of soil fauna of the boreal forest …