Search results for "FOREST"
showing 10 items of 3780 documents
The impact of economic, social and political factors on the landscape structure of the Vidzeme Uplands in Latvia
2005
Abstract Changes in landscape structure in a typical part of the Vidzeme Uplands in central Latvia during the 20th century are analysed and anticipated changes in the 21st century are projected. Forest areas gradually increased in the Vidzeme Uplands over the course of the 20th century. This increase was associated with several factors: the economic policy in Latvia during the 1930s, the exile of farmers in 1940 and 1949 after the Soviet occupation of Latvia, the aggregation of land into collective farms, the amalgamation of small collective farms, the formation of large-scale Soviet collective farms, and widespread land melioration. Since land reform in the 1990s, following the restoration…
Assessment of site-specific drivers of farmland abandonment in mosaic-type landscapes: A case study in Vidzeme, Latvia
2018
Abstract Farmland abandonment, which causes changes in rural life and farming practices, can be observed throughout Europe. Over the last decades natural afforestation has decreased the area of farmland used for agricultural production, thereby leading to landscape homogenization and polarization. This process is explicitly evident in mosaic type landscapes consisting of highly complex land cover patterns, soil composition and topography. The aim of the study was to determine the site-specific driving forces of farmland abandonment at landscape scale in relation to agro-ecological and geographic factors, in a post-Soviet country in Eastern Europe. An extensive field survey approach with sta…
Relationships between climatic parameters and forest vegetation: application to burned area in Alicante (Spain)
2000
Abstract The main aims of this study is to examine the variability of normalized difference vegetation index (NDVI) on forest vegetation in Alicante (Spain) between 1984 and 1994 and to analyse the influence of climatic parameters in the regeneration of forest areas burned by fires. The zone of study is located between XUTM (m) 730400-760400 and YUTM (m) 4274000-4304000 and is characterised by a great topographic complexity that leads to diverse microclimatic conditions. In this area, the maximum annual rainfall of the Valencian Community is recorded, reaching 850 mm of average annual rainfall ( Belda, 1997 ). We examined the spatial and temporal analyse of rainfall and soil moisture over t…
Photosynthesis and transpiration of healthy and diseased spruce trees in the course of three vegetation periods
1988
CO2- and H2O-gas exchange of 20- to 25-year-old spruce trees from a plantation in the Hunsruck mountains were investigated over a period of 3 years. All measurements were made as pair comparisons, i.e., in each case the gas exchange of a damaged tree and of a relatively healthy tree in its immediate vicinity was measured simultaneously. A second plantation in the Westerwald mountains consisted of 18-year-old apparently healthy spruce trees. Pair comparison at this location meant comparison of two healthylooking trees. The investigations at both locations included diurnal course measurements of photosynthesis and transpiration, and light saturation curves and CO2-saturation curves of photosy…
Long-Term Effects of Climate Warming on Forest Soil Collembola
2005
Long-term changes in the collembolan community structure were studied in a Scots pine forest in northern Latvia over a period of 11 successive years (1992–2002). Soil Collembola were yearly sampled from three pine forest stands of different age – young (30 to 40 years old), middle-aged (50 to 70 years old) and old (150 to 200 years old). During the study period a statistically significant increase in sums of positive temperatures (>+4°C) was recorded and a gradual decrease in species richness of Collembola was observed in all forest stands. The study showed that sums of positive air temperatures produce statistically significant effects on collembolan populations. Community responses were s…
A new association of relict maquis with Ptilostemon greuteri (Oleo-Ceratonion, Quercetea ilicis), located in a circumscribed area of north-western Si…
2022
This paper illustrates the results of a survey aimed at deepening available knowledge on the ecology of Ptilostemon greuteri (Asteraceae), a very rare palaeoendemic and relict nano-phanerophyte discovered about 15 years ago on Monte Inici, near Castellammare del Golfo (province of Trapani, north-western Sicily). Two plant communities characterised by P. greuteri are described in detail; they occur in the locus classicus and in a second, recently discovered stand, which is also very localised and threatened by fire. The field investigations revealed that the sites where the species grows are very similar from the ecological point of view; in fact, both of them are located on the steep slopes…
Relevant habitats neglected by the Directive 92/43 EEC: the contribution of Vegetation Science for their reappraisal in Sicily
2021
Field investigation carried out by the Sicilian botanists in the last 20 years enabled them to identify eight habitat types of high biogeographic and conservation interest, neglected by the Directive 92/43, which deservead hocconservation measures. For each of these habitats, a syntaxonomic interpretation of the corresponding plant communities, their main ecological, physiognomic and syndynamic traits and a list of diagnostic species are provided. Their classification into the macrotypes listed in the Annex I of the Directive 92/43 and the respective correspondence in EUNIS habitat classification are proposed. The habitats here described integrate those already proposed by the Italian Botan…
Role of the Siberian flying squirrel as an umbrella species for biodiversity in northern boreal forests
2008
Abstract One of the potentially useful indirect shortcut methods in biodiversity conservation is the umbrella species concept. An umbrella species can be seen relatively demanding for the size of the area and probably also for certain habitat types: conservation management for the umbrella species would thus encompass other species preferring similar habitats but with smaller area requirements. As such, it has a comprehensive spatial aspect for landscape planning. We tested the role of the Siberian flying squirrel ( Pteromys volans ) as an umbrella species for wood dependent species among red-listed and old-growth forest associated polypores, epiphytic lichens and beetles. Flying squirrels …
Evaluation, Analysis and Perception of Sustainable Forest Management Through the Lens of the PEFC Forest Certification Using Two Case Studies in Sici…
2019
Sustainable forest management has reached a common understanding between scientific and technical definitions. A series of criteria and indicators have been implemented for monitoring the effectiveness of the management in functional and structural terms, and to evaluate its effects on ecosystem services of forests. Currently, Sicily has no forest areas with certification of sustainable forest management and in order to evaluate the diffusion of knowledge of certification schemes and their importance in SFM, a questionnaire survey was carried out during a foresters' workshop on the island. The possibility of applying the criteria and indicators of PEFC certification of sustainable forest ma…
Toxic impact of the de-icing material to street greenery in Riga, Latvia
2008
Abstract There is little information on the ecological composition of snow on roads as well as the toxic effect of de-icing salt on the ecological status of the street trees ( Tilia x vulgaris H.) in Latvia. Tilia x vulgaris is one of the most widespread tree species of street greenery in the boreo-nemoral zone – in Central, Northern and Eastern Europe. This investigation was done to find out the accumulation of de-icing salt (main elements – sodium and chlorine) in the snow–soil–plant system of street greenery in the central part of Riga (2004–2005), in order to reveal the toxic effect on the ecological status of the street trees ( Tilia x vulgaris ). Snow, soil and leaf samples were colle…