12 research outputs found
Wood pastures in Central Slovakia – collapse of a traditional land use form
Wood pastures with pollard trees have been a common land-use type across Europe. The trees, besides having positive environmental effects on livestock, served as important source of fodder and wood. Pollarded wood pastures were hence a multifunctional, state of the art, highly productive farming ecosystems. Despite relatively drastic treatment, the trees regenerated quite well, and grew to relatively high-age. When pollarding lapses for longer period the wood pasture may confusingly resemble an ancient forest. Using aerial photographs of Slovakia from 1949–1950 we have identified 950 individual wood pasture localities with total area of 265.5 km2 within the Self-Governing Region of Banská Bystrica. Majority of identified wood pasture habitats were actively managed in the first half of the 20th century. Nowadays, less than 2.5% has preserved its original structure, the rest has been abandoned (92.8%) or actively transformed into different land-use form. We conducted a field survey in order to identify historical pollarding within the Gavurky protected area, one of the last and best preserved wood pastures in Slovakia. By evaluating habitual features, we were able to confirm historical pollarding for more than 80% of present veteran trees. We provide framework for identification of pollarding in historical wood pasture localities, applicable in the conditions of long-term management cessation
Quantification of the Cooling Effect and Cooling Distance of Urban Green Spaces Based on Their Vegetation Structure and Size as a Basis for Management Tools for Mitigating Urban Climate
The urban climate is receiving increased attention mainly due to climate change. There are several ways to mitigate the urban climate, but green spaces have an advantage over other cooling systems because, in addition to their climate function, they provide several other ecosystem services that enhance the sustainability of urban systems. The cooling effect of green spaces varies depending on their species composition, the structure of the vegetation, the size and shape of the green spaces or the specific characteristics of the plants. Therefore, the exact quantification of urban green space’s cooling effect is of critical importance in order to be effectively applied in urban planning as a measure of climate change adaptation. In this paper, we quantified the difference in the cooling effect between urban green spaces depending on their vegetation structure (grass versus trees) and their size, and assessed to what distance from the urban green space its cooling effect can be observed. Urban green spaces were identified using Landsat orthophotomosaic and airborne laser scanning. The urban temperature was calculated as the land surface temperature (LST) from Landsat data using a single-channel method. To quantify differences in the magnitude of the cooling effect of green spaces and the distance from the edge of the green space over which the cooling effect occurs, we used a one-way analysis of variance and regression analyses. Our results show that the cooling intensity, as well as the cooling distance, are dependent on the size and structure of the green space. The most significant cooling effect is provided by large green tree spaces, where the cooling intensity (difference of LST compared to an urban area without vegetation) was almost 4.5 °C on average (maximum almost 6 °C) and the cooling distance was significant up to 90 m (less significantly up to 180 m). Large grass spaces and medium tree spaces have similar effects, with a higher cooling intensity (2.9 °C versus 2.5 °C on average) however, the cooling effect extends to a greater distance (up to 90 m) for medium tree spaces compared to large grass spaces, where the cooling effect only extends to 30–60 m. Small areas with trees and medium and small grass areas without trees have an average cooling intensity below 2 °C
Mitigating Effect of Urban Green Spaces on Surface Urban Heat Island during Summer Period on an Example of a Medium Size Town of Zvolen, Slovakia
Climate change affects the urban population’s health and quality of life. Urban green spaces (UGS) underpin several essential ecosystem services, amongst them climate regulation. Urban vegetation mitigates high temperatures and, thus, reduces the heat stress for urban residents. The study aimed to verify whether the Surface Urban Heat Island (SUHI) effect manifests itself even in a medium size town (Zvolen, Slovakia) surrounded by agricultural and forested landscape and to quantify the temperature mitigating effect of urban green spaces. Land surface temperature (LST) and SUHI distribution were derived from the Landsat data during the summer months of 2010–2021. To statistically prove the cooling effect of the urban vegetation, we tested (by one-way ANOVA) LST within three urban zones of the Zvolen municipality defined by the Copernicus imperviousness density data: (a) dense urban area (31–100% impervious surfaces), (b) discontinuous urban area (1–30% impervious surfaces), (c) urban green spaces (0% impervious surfaces), and the open land surrounding the town (0% impervious surfaces). The results showed a statistical difference in temperatures between all urban areas (all zones) and the open land. Moreover, the UGS temperature was statistically different compared to the other urban zones. The mean temperature difference through the years 2010–2021 between urban green spaces and the dense urban area was 3.5 °C, with a maximum of 4.9 °C and a minimum 1.7 °C in favor of the urban spaces. Moreover, the temperature of urban green spaces and open land varied during the studied summer period. The warmer the weather, the higher the difference, while at the end of August, on a notably colder day, there was no significant difference between them. The results confirmed that UGS are significantly cooler during hot days, and they can mitigate the local climate
Mitigating Effect of Urban Green Spaces on Surface Urban Heat Island during Summer Period on an Example of a Medium Size Town of Zvolen, Slovakia
Climate change affects the urban population’s health and quality of life. Urban green spaces (UGS) underpin several essential ecosystem services, amongst them climate regulation. Urban vegetation mitigates high temperatures and, thus, reduces the heat stress for urban residents. The study aimed to verify whether the Surface Urban Heat Island (SUHI) effect manifests itself even in a medium size town (Zvolen, Slovakia) surrounded by agricultural and forested landscape and to quantify the temperature mitigating effect of urban green spaces. Land surface temperature (LST) and SUHI distribution were derived from the Landsat data during the summer months of 2010–2021. To statistically prove the cooling effect of the urban vegetation, we tested (by one-way ANOVA) LST within three urban zones of the Zvolen municipality defined by the Copernicus imperviousness density data: (a) dense urban area (31–100% impervious surfaces), (b) discontinuous urban area (1–30% impervious surfaces), (c) urban green spaces (0% impervious surfaces), and the open land surrounding the town (0% impervious surfaces). The results showed a statistical difference in temperatures between all urban areas (all zones) and the open land. Moreover, the UGS temperature was statistically different compared to the other urban zones. The mean temperature difference through the years 2010–2021 between urban green spaces and the dense urban area was 3.5 °C, with a maximum of 4.9 °C and a minimum 1.7 °C in favor of the urban spaces. Moreover, the temperature of urban green spaces and open land varied during the studied summer period. The warmer the weather, the higher the difference, while at the end of August, on a notably colder day, there was no significant difference between them. The results confirmed that UGS are significantly cooler during hot days, and they can mitigate the local climate
Quantification of the Cooling Effect and Cooling Distance of Urban Green Spaces Based on Their Vegetation Structure and Size as a Basis for Management Tools for Mitigating Urban Climate
The urban climate is receiving increased attention mainly due to climate change. There are several ways to mitigate the urban climate, but green spaces have an advantage over other cooling systems because, in addition to their climate function, they provide several other ecosystem services that enhance the sustainability of urban systems. The cooling effect of green spaces varies depending on their species composition, the structure of the vegetation, the size and shape of the green spaces or the specific characteristics of the plants. Therefore, the exact quantification of urban green space’s cooling effect is of critical importance in order to be effectively applied in urban planning as a measure of climate change adaptation. In this paper, we quantified the difference in the cooling effect between urban green spaces depending on their vegetation structure (grass versus trees) and their size, and assessed to what distance from the urban green space its cooling effect can be observed. Urban green spaces were identified using Landsat orthophotomosaic and airborne laser scanning. The urban temperature was calculated as the land surface temperature (LST) from Landsat data using a single-channel method. To quantify differences in the magnitude of the cooling effect of green spaces and the distance from the edge of the green space over which the cooling effect occurs, we used a one-way analysis of variance and regression analyses. Our results show that the cooling intensity, as well as the cooling distance, are dependent on the size and structure of the green space. The most significant cooling effect is provided by large green tree spaces, where the cooling intensity (difference of LST compared to an urban area without vegetation) was almost 4.5 °C on average (maximum almost 6 °C) and the cooling distance was significant up to 90 m (less significantly up to 180 m). Large grass spaces and medium tree spaces have similar effects, with a higher cooling intensity (2.9 °C versus 2.5 °C on average) however, the cooling effect extends to a greater distance (up to 90 m) for medium tree spaces compared to large grass spaces, where the cooling effect only extends to 30–60 m. Small areas with trees and medium and small grass areas without trees have an average cooling intensity below 2 °C
Modification of the potential production capabilities of agricultural terrace soils due to historical cultivation in the Budina cadastral area, Slovakia
The soil production attributes of historical agrarian terraced fields were examined in the Budina cadastral area of the Ostrozky Mountains. This landscape represents a unique sub-mountainous Carpathian landscape with farms that use a historically preserved triple-field agricultural system. We determined the geo-spatial parameters of different types of land cover and terraces using geographic information systems. The soil depth was measured in the field, and the skeleton content was determined in the laboratory. We compared data regarding the potential production capabilities of the soil with data from the national classification of agricultural soils. Our results indicated that the soil productivity attributes improved because the naturally less fertile cambisols were positively affected by terracing and long-term cultivation. We recommend the preservation of traditional agricultural activities in historical terraced fields because these terraces represent valuable features that improve the quality of the landscape
Modification of the potential production capabilities of agricultural terrace soils due to historical cultivation in the Budina cadastral area, Slovakia
The soil production attributes of historical agrarian terraced fields were examined in the Budina cadastral area of the Ostrozky Mountains. This landscape represents a unique sub-mountainous Carpathian landscape with farms that use a historically preserved triple-field agricultural system. We determined the geo-spatial parameters of different types of land cover and terraces using geographic information systems. The soil depth was measured in the field, and the skeleton content was determined in the laboratory. We compared data regarding the potential production capabilities of the soil with data from the national classification of agricultural soils. Our results indicated that the soil productivity attributes improved because the naturally less fertile cambisols were positively affected by terracing and long-term cultivation. We recommend the preservation of traditional agricultural activities in historical terraced fields because these terraces represent valuable features that improve the quality of the landscape.475
TCF12 controls oligodendroglial cell proliferation and regulates signaling pathways conserved in gliomas
International audienceAbstract Diffuse gliomas are primary brain tumors originating from the transformation of glial cells. In particular, oligodendrocyte precursor cells constitute the major tumor-amplifying population in the gliomagenic process. We previously identified the TCF12 gene, encoding a transcription factor of the E protein family, as being recurrently mutated in oligodendrogliomas. In this study, we sought to understand the function of TCF12 in oligodendroglial cells, the glioma lineage of origin. We first describe TCF12 mRNA and protein expression pattern in oligodendroglial development in the mouse brain. Second, by TCF12 genome wide chromatin profiling in oligodendroglial cells, we show that TCF12 binds active promoters of genes involved in proliferation, translation/ribosomes, and pathways involved in oligodendrocyte development and cancer. Finally, we perform OPC-specific Tcf12 inactivation in vivo and demonstrate by immunofluorescence and transcriptomic analyses that TCF12 is transiently required for OPC proliferation but dispensable for oligodendrocyte differentiation. We further show that Tcf12 inactivation results in deregulation of biological processes that are also altered in oligodendrogliomas. Together, our data suggest that TCF12 directly regulates transcriptional programs in oligodendroglia development that are relevant in a glioma context
Distribution of Wood Pastures in Slovakia—Constraints and Potentials for Restoration of Multifunctional Traditional Land Use Form
Wood pastures represent specific ecosystems across Europe with diverse ecological, agricultural, and socioeconomic roles. Land-use changes and the cessation of traditional management in conjunction with socioeconomic changes led to shifts in their spatiotemporal distribution. Despite a recent increase in scientific interest, data on historical patterns of wood pastures in many European locations remain insufficient. This study presents wood-pasture habitat continuity and analyzes changes in their distribution over space and time in selected parts of Slovakia. Simultaneously, we analyzed the relation of wood pastures to selected environmental and landscape features. To achieve this, we examined the historical distribution of wood pastures using aerial imagery from the 1950s. We thoroughly examined an area of 16,209 km2 to identify preserved wood pastures. To identify the present conditions and the spatial distribution of wood-pasture habitats, we compared the historical data with recent ortophotomaps. Based on landscape–ecological analyses of historical distribution, we determined prevailing environmental conditions of wood-pasture locations. The findings reveal that over 90% of wood pastures from the first half of the 20th century have now been lost or encroached and preserved in the form of a closed-canopy forest. In most of the encroached sites, we identified the presence of vital core veteran trees. For the identification of wood pastures and further analyses of the environmental variables, the ArcGIS 10.3 program was used; the R software was used for all statistical evaluations. The results show that the studied wood pastures were not established randomly, but were rather set within a certain landscape context, characterized by elevation, soil quality, and distance from settlements
Mapping Soil Degradation on Arable Land with Aerial Photography and Erosion Models, Case Study from Danube Lowland, Slovakia
The presented study uses the recent colour aerial photographs, historical black and white aerial photographs, and detailed digital elevation model to assess the spatial distribution and long-term temporal dynamics of soil loss in agriculturally intensively exploited loess hilly land with a subcontinental temperate climate. The strongly eroded soils appear in the studied area as bright patterns, surrounded by darker soils, and they are well visible on aerial photos. Three approaches of interpretation of aerial photographs were tested: visual interpretation, pixel-based image classification, and object-based image classification. All three methods provided detailed maps of soil redistribution patterns. The bright areas as the areas of soil degradation characterized by erosion increased from 1949 until 2011 by 76%. A detailed map of areal erosion patterns was used for the validation of water erosion models. LS-factor of USLE and ED’ index of USPED were selected for expressing the relation of real erosion to the terrain. The relationship between surface morphology and real erosion is very complex, and the tested water erosion models do not express it sufficiently. Therefore, the first and second-order directional derivative of the surface elevations with respect to the tillage direction has been tested. The absolute value of the first-order directional derivative showed better results and better corresponded with the real erosion pattern than the other morphometric characteristics. The findings suggest that tillage is the dominant erosion factor in the area