Charcoal deposits in forest soils have been considered mainly in the context of wildfires. Howeve... more Charcoal deposits in forest soils have been considered mainly in the context of wildfires. However, slash-and-burn cultivation has been widespread in Northern Europe until the beginning of the 20th century and extensive areas of former swiddens are now covered by forests. The study sites were in Karula National Park in Southern Estonia. 19th-century cadastral maps were used to identify the historical land use. Macroscopic (visible) charcoal was studied in 57 soil pits, located in historical slash-and-burn sites, forests, former arable fields, recent forest fire sites, and experimental slash-and-burn fields. The locations of charcoal in the soil profile were recorded. In four sites, the charcoal samples were dated. Charcoal is widespread in boreal forest soils. A considerable proportion of this could originate from historical slash-and-burn cultivation. The charcoal depth was related to agricultural land use duration and methods at different intensities. The location of the charcoal-...
Coastal wetlands provide a range of important ecosystem services, yet they are under threat from ... more Coastal wetlands provide a range of important ecosystem services, yet they are under threat from a range of stressors including climate change. This is predominantly as a result of alterations to the hydroregime and associated edaphic factors. We used a three year mesocosm experiment to assess changes in coastal plant community composition for three plant communities in response to altered water level and salinity scenarios. Species richness and abundance were calculated by year and abundance was plotted using rank abundance curves. The permutational multivariate analysis of variance with Bray-Curtis dissimilarity was used to examine differences among treatments in plant community composition. A principal coordinate analysis was used to visualize the responses of communities to treatments by year. Results showed that all three plant communities responded differently to altered water levels and salinity. Species richness and abundance increased significantly in an Open Pioneer while ...
<p>Coastal wetlands are considered valuable ecosystems for their biodiversi... more <p>Coastal wetlands are considered valuable ecosystems for their biodiversity and the wide range of ecosystem services they supply. However, coastal wetlands worldwide are also subject to various impacts resulting from natural and anthropogenic drivers, such as urbanization and residential developments, conversion to agricultural land and climate change related impacts such as sea level rise, changes in precipitation, inundation, changes in salinity and erosion. The consequences of climate change over recent decades are evident in the Baltic Sea region, with modifications in sea water circulation, temperature and salinity. Due to the high importance of coastal wetlands and the impacts of climate change on this ecosystem, it is essential to determine how future conditions will influence coastal plant community functioning. In the Baltic Sea, both salinity and water levels have been shown to have a strong influence on coastal plant community composition. In order to assess the effects of climate change in coastal wetlands, an investigation of the influence of changes in water level and salinity on coastal wetland plant communities was undertaken. Future scenarios of Baltic coastal wetlands were evaluated using a three-year mesocosm experiment simulating altered environmental conditions. The response of three plant communities (Open Pioneer-OP, Lower Shore-LS and Upper Shore-US) were assessed in terms of changes in species composition over time. The experiment included 45 mesocosms, 15 per community with 5 treatments (3 replicates per treatment) with control, altered water level and salinity. In order to analyse the differences among treatments in plant communities through time, Permutational Multivariate analysis of variance (PERMANOVA) and species contribution were performed. Bray-Curtis dissimilarity was calculated from species importance values. Finally, a principal coordinate analysis (PCoA) based on Bray-Curtis dissimilarity was used to visualize the responses of the communities to treatments in each year. The results showed that all factors, year and treatment, influenced plant community composition. PCoA revealed plant community shifts in OP in the second year of experiment. Species were more clustered in LS and US communities compared to OP, but changes were still noted. The small spread of species throughout the years in ordination space in LS and US suggests a higher degree of similarity between communities across treatments. Based on these mesocosm experiments, it can be concluded that altered water level and salinity in Baltic coastal wetlands can have important consequences for species composition in plant communities, which support high diversity and are important for conservation.</p>
Throughout the second half of the 20th Century the area of semi-natural grasslands in Estonia dec... more Throughout the second half of the 20th Century the area of semi-natural grasslands in Estonia decreased substantially, partly due to the collectivization process during the soviet era leading to agricultural abandonment in some areas and intensification in more productive soil types (Henle et al. 2008). Both of these processes led to declines in species diversity as well as homogenisation and loss of character. Within calcareous grasslands loss of grazing leads to colonization by scrub including juniper (Juniperus communis) with very few species and a very different structure, and similar processes occur in other semi-natural grassland types.The unique biodiversity value of semi-natural grasslands in Estonia is well recognised (Dengler et al. 2014), however, an estimation of their value is required to demonstrate to policy makers the urgent requirement for conservation measures. The ecosystem services framework provides a new approach to assess the value and multi-functionality of t...
Within animal communities the loss of a single keystone species can lead to substantial change, o... more Within animal communities the loss of a single keystone species can lead to substantial change, or in extreme cases, community collapse. This phenomenon has been documented in different communities and habitats but has not been widely investigated in bird communities. We studied the long-term dynamics of breeding birds in a medium-sized hemiboreal lake that is situated within a large primary forest-mire-lake ecosystem in central-east of Estonia. The aim of this 25 year study was to determine whether the black-headed gull, Larus ridibundus, acts as a keystone species in the bird community and what was the effect of the loss of this species. Results revealed large changes in the bird community similar to those that would occur in a fragile system in response to keystone species loss, confirming our theory. Mallard Anas platyrhynchos, common pochard Aythya ferina, tufted duck Aythya fuligula, great crested grebe Podiceps cristatus, red-necked grebe Podiceps grisegena, Eurasian marsh ha...
Abstract. Very small amounts of pharmaceuticals present in everyday food may generate strains of ... more Abstract. Very small amounts of pharmaceuticals present in everyday food may generate strains of resistant microorganisms in human and animal organisms. This study involves the uptake and accumulation of some widely used fluoroquinolones – enrofloxacin and ciprofloxacin – by plants cultivated in soil augmented with drugs using the microbiological agar diffusion method. Bacillus subtilis was used as the test bacterium. The three plants chosen for the experiment were lettuce (Lactuca sativa), common barley (Hordeum vulgare L.) and cucumber (Cucumis sativus L.), which were cultivated in a laboratory in soils mixed with enroor ciprofloxacin at nominal concentrations of 500, 200, 50 and 10 μg/g. The concentrations of fluoroquinolones remained unchanged in the soil during the experiment. The presence of enrofloxacin was detected in all plants grown at enrofloxacin concentrations of 500, 200 and 50 μg/g. The presence of ciprofloxacin was only detected in barley and cucumber grown in soil w...
... Foreign Title Vihmaussikoosluse muutustest mahe-ja tavakülvikorrakatses. Authors Ivask, M.; S... more ... Foreign Title Vihmaussikoosluse muutustest mahe-ja tavakülvikorrakatses. Authors Ivask, M.; Sepp, K.; Kanger, J. Editor Kadaja, J. Book chapter; Conference paper Agronomy 2007 2007 pp. 13-16 Conference Title Agronomy 2007, Saku, Estonia, 2007. ...
Charcoal deposits in forest soils have been considered mainly in the context of wildfires. Howeve... more Charcoal deposits in forest soils have been considered mainly in the context of wildfires. However, slash-and-burn cultivation has been widespread in Northern Europe until the beginning of the 20th century and extensive areas of former swiddens are now covered by forests. The study sites were in Karula National Park in Southern Estonia. 19th-century cadastral maps were used to identify the historical land use. Macroscopic (visible) charcoal was studied in 57 soil pits, located in historical slash-and-burn sites, forests, former arable fields, recent forest fire sites, and experimental slash-and-burn fields. The locations of charcoal in the soil profile were recorded. In four sites, the charcoal samples were dated. Charcoal is widespread in boreal forest soils. A considerable proportion of this could originate from historical slash-and-burn cultivation. The charcoal depth was related to agricultural land use duration and methods at different intensities. The location of the charcoal-...
Coastal wetlands provide a range of important ecosystem services, yet they are under threat from ... more Coastal wetlands provide a range of important ecosystem services, yet they are under threat from a range of stressors including climate change. This is predominantly as a result of alterations to the hydroregime and associated edaphic factors. We used a three year mesocosm experiment to assess changes in coastal plant community composition for three plant communities in response to altered water level and salinity scenarios. Species richness and abundance were calculated by year and abundance was plotted using rank abundance curves. The permutational multivariate analysis of variance with Bray-Curtis dissimilarity was used to examine differences among treatments in plant community composition. A principal coordinate analysis was used to visualize the responses of communities to treatments by year. Results showed that all three plant communities responded differently to altered water levels and salinity. Species richness and abundance increased significantly in an Open Pioneer while ...
<p>Coastal wetlands are considered valuable ecosystems for their biodiversi... more <p>Coastal wetlands are considered valuable ecosystems for their biodiversity and the wide range of ecosystem services they supply. However, coastal wetlands worldwide are also subject to various impacts resulting from natural and anthropogenic drivers, such as urbanization and residential developments, conversion to agricultural land and climate change related impacts such as sea level rise, changes in precipitation, inundation, changes in salinity and erosion. The consequences of climate change over recent decades are evident in the Baltic Sea region, with modifications in sea water circulation, temperature and salinity. Due to the high importance of coastal wetlands and the impacts of climate change on this ecosystem, it is essential to determine how future conditions will influence coastal plant community functioning. In the Baltic Sea, both salinity and water levels have been shown to have a strong influence on coastal plant community composition. In order to assess the effects of climate change in coastal wetlands, an investigation of the influence of changes in water level and salinity on coastal wetland plant communities was undertaken. Future scenarios of Baltic coastal wetlands were evaluated using a three-year mesocosm experiment simulating altered environmental conditions. The response of three plant communities (Open Pioneer-OP, Lower Shore-LS and Upper Shore-US) were assessed in terms of changes in species composition over time. The experiment included 45 mesocosms, 15 per community with 5 treatments (3 replicates per treatment) with control, altered water level and salinity. In order to analyse the differences among treatments in plant communities through time, Permutational Multivariate analysis of variance (PERMANOVA) and species contribution were performed. Bray-Curtis dissimilarity was calculated from species importance values. Finally, a principal coordinate analysis (PCoA) based on Bray-Curtis dissimilarity was used to visualize the responses of the communities to treatments in each year. The results showed that all factors, year and treatment, influenced plant community composition. PCoA revealed plant community shifts in OP in the second year of experiment. Species were more clustered in LS and US communities compared to OP, but changes were still noted. The small spread of species throughout the years in ordination space in LS and US suggests a higher degree of similarity between communities across treatments. Based on these mesocosm experiments, it can be concluded that altered water level and salinity in Baltic coastal wetlands can have important consequences for species composition in plant communities, which support high diversity and are important for conservation.</p>
Throughout the second half of the 20th Century the area of semi-natural grasslands in Estonia dec... more Throughout the second half of the 20th Century the area of semi-natural grasslands in Estonia decreased substantially, partly due to the collectivization process during the soviet era leading to agricultural abandonment in some areas and intensification in more productive soil types (Henle et al. 2008). Both of these processes led to declines in species diversity as well as homogenisation and loss of character. Within calcareous grasslands loss of grazing leads to colonization by scrub including juniper (Juniperus communis) with very few species and a very different structure, and similar processes occur in other semi-natural grassland types.The unique biodiversity value of semi-natural grasslands in Estonia is well recognised (Dengler et al. 2014), however, an estimation of their value is required to demonstrate to policy makers the urgent requirement for conservation measures. The ecosystem services framework provides a new approach to assess the value and multi-functionality of t...
Within animal communities the loss of a single keystone species can lead to substantial change, o... more Within animal communities the loss of a single keystone species can lead to substantial change, or in extreme cases, community collapse. This phenomenon has been documented in different communities and habitats but has not been widely investigated in bird communities. We studied the long-term dynamics of breeding birds in a medium-sized hemiboreal lake that is situated within a large primary forest-mire-lake ecosystem in central-east of Estonia. The aim of this 25 year study was to determine whether the black-headed gull, Larus ridibundus, acts as a keystone species in the bird community and what was the effect of the loss of this species. Results revealed large changes in the bird community similar to those that would occur in a fragile system in response to keystone species loss, confirming our theory. Mallard Anas platyrhynchos, common pochard Aythya ferina, tufted duck Aythya fuligula, great crested grebe Podiceps cristatus, red-necked grebe Podiceps grisegena, Eurasian marsh ha...
Abstract. Very small amounts of pharmaceuticals present in everyday food may generate strains of ... more Abstract. Very small amounts of pharmaceuticals present in everyday food may generate strains of resistant microorganisms in human and animal organisms. This study involves the uptake and accumulation of some widely used fluoroquinolones – enrofloxacin and ciprofloxacin – by plants cultivated in soil augmented with drugs using the microbiological agar diffusion method. Bacillus subtilis was used as the test bacterium. The three plants chosen for the experiment were lettuce (Lactuca sativa), common barley (Hordeum vulgare L.) and cucumber (Cucumis sativus L.), which were cultivated in a laboratory in soils mixed with enroor ciprofloxacin at nominal concentrations of 500, 200, 50 and 10 μg/g. The concentrations of fluoroquinolones remained unchanged in the soil during the experiment. The presence of enrofloxacin was detected in all plants grown at enrofloxacin concentrations of 500, 200 and 50 μg/g. The presence of ciprofloxacin was only detected in barley and cucumber grown in soil w...
... Foreign Title Vihmaussikoosluse muutustest mahe-ja tavakülvikorrakatses. Authors Ivask, M.; S... more ... Foreign Title Vihmaussikoosluse muutustest mahe-ja tavakülvikorrakatses. Authors Ivask, M.; Sepp, K.; Kanger, J. Editor Kadaja, J. Book chapter; Conference paper Agronomy 2007 2007 pp. 13-16 Conference Title Agronomy 2007, Saku, Estonia, 2007. ...
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