Areas In Estonia Research Articles

Aboveground biomass and nutrient accumulation dynamics in young black alder, silver birch and Scots pine plantations on reclaimed oil shale mining areas in Estonia

The growth, aboveground biomass production and nutrient accumulation in black alder ( Alnus glutinosa (L.) Gaertn.), silver birch ( Betula pendula Roth.) and Scots pine ( Pinus sylvestris L.) plantations during 7 years after planting were investigated on reclaimed oil shale mining areas in Northeast Estonia with the aim to assess the suitability of the studied species for the reclamation of post-mining areas. The present study revealed changes in soil properties with increasing stand age. Soil pH and P concentration decreased and soil N concentration increased with stand age. The largest height and diameter of trees, aboveground biomass and current annual production occurred in the black alder stands. In the 7-year-old stands the aboveground biomass of black alder (2100 trees ha −1) was 2563 kg ha −1, in silver birch (1017 trees ha −1) and Scots pine (3042 trees ha −1) stands respective figures were 161 and 1899 kg ha −1. The largest amounts of N, P, K accumulated in the aboveground part were in black alder stands. In the 7th year, the amount of N accumulated in the aboveground biomass of black alder stand was 36.1 kg ha −1, the amounts of P and K were 3.0 and 8.8 kg ha −1, respectively. The larger amounts of nutrients in black alder plantations are related to the larger biomass of stands. The studied species used N and P with different efficiency for the production of a unit of biomass. Black alder and silver birch needed more N and P for biomass production, and Scots pine used nutrients most efficiently. The present study showed that during 7 years after planting, the survival and productivity of black alder were high. Therefore black alder is a promising tree species for the reclamation of oil shale post-mining areas.

From Soviet to Post-Soviet with Transformation of the Fragmented Urban Landscape: The Case of Garage Areas in Estonia

While every social formation creates its specific landscape, the landscape is never homogenous but is rather fragmented. In addition to the elements that have been formed under the forces of the current era, the landscape also contains elements from previous eras. Functions of some of these landscapes have changed, reflecting societal conditions as other elements may have preserved their previous function. The garage area is one of the examples of the last case as it proliferated in the former Soviet socialist system where it had an importance in dealing with the system's shortcomings. With the fall of the Soviet system, garage areas have not been demolished and are still in use. Hence, the aim of this paper is to analyze the dynamics of urban landscape by applying Widgren's ‘formal procedure of reading landscapes’ and its terms form, function, context and processes using garage areas in the transformation of Estonian society as a case study. The paper analyzes two aspects. First, it shows how the formation of garage areas was conditioned by the Soviet system. Second, it will discuss how the ownership system in connection with preservation of functions has been able to influence the persistence of garage areas. While being a detail that enables insight into socialist as well as Western societies, garage areas have not received attention in previous literature.

Hydrogeologic impacts in the Estonian oil shale deposit

The article describes the hydrogeological problems related to water influx to the mine and water sulphate content association with underground oil shale mining in an environmentally sensitive area of Estonia. The water balance method was used to calculate the ratio of mine water outflow/inflow. Water balance calculations are needed for estimating the groundwater transversal flow into closed mines. Before oil shale mining groundwater geochemical processes are characterised by low sulphate content. Dewatering of oil shale mines lowered groundwater level in the Keila–Kukruse aquifer, and caused an about 50-fold increase in sulphate by intensive oxidation of pyrite of natural origin. The mobile sulphate ion may serve as an indicator of changes occurring in the sulphate content of groundwater stored in the Keila–Kukruse and Lasnamäe–Kunda aquifers of the Ordovician system in the area of closed and working mines. Using the method of inverse mixing, sulphate ion distribution is a possibility to study the movement of groundwater in lateral and transversal directions.

Preadaptation and spatial effects on retention-tree survival in cut areas in Estonia

Survival of live retention trees is a key issue for stand-scale applications of natural-disturbance-based silviculture. We explored the survival of 3255 trees in 102 cut areas (mean size 2.3 ha) in Estonia for 6 years, focusing on spatial variation and preadaptation of the trees. Altogether, 35% of the trees died during the study period, contributing 4.4 m3 of downed dead trunks and 1 m3 of standing dead trees per hectare. The annual mortality rates declined over time. The main survival determinants were tree species (higher for hardwood deciduous trees), diameter (species dependent), position relative to forest edge (higher for trees near current or former forest edges), retention density (positive), and exposure (negative). The results suggest that (1) green-tree retention can effectively increase the abundance of large shade-tolerant trees, but it is equally important for producing deadwood; (2) larger individuals, former interior-forest trees near current forest edges, and preadapted trees in open conditions should be preferably retained; (3) there is no obvious necessity to modify tree-retention techniques for tree survival according to geographical region or forest site type.

Beyond words: dance and movement sessions with young people with social, emotional and behavioural difficulties in Estonia

This article details an experimental project in Estonian schools, using therapeutic dance and movement as a basis to explore beyond the boundaries of language in supporting young people to develop their creative expression. The author visited three residential schools in different areas of Estonia in September 2006 to lead sessions with groups of young people who had a range of social, emotional and behavioural problems. This personal account details the aims of the project, the sessions and the experiences of those involved. It asks: can dance and movement offer a creative and dynamic form for expression, beyond the boundaries of culture and language, for those troubled and damaged young people who often struggle to communicate and express with words?

‘Maps of meaning’: Landscapes on the map and in the mind – discovering Paldiski, estonia

The article explores relationships between representations (maps) and the represented (landscape), focusing on the role of maps in creating places and as devices in the generation and manipulation of knowledge. The production and use of maps is seen as part of power relations in society, referred to in Foucault's term as ‘games of strategy’, including dominance and control of the natural environment and the social system, but also resistance to and negotiation of power positions in society. The main objective is to examine the meanings given to one limited area in Estonia, Paldiski – covering the Pakri peninsula – by presenting its contemporary content and considering different angles for interpretation. The real and assumed ties between the physical environment and past and present representations are conveyed in the descriptive form of a map of a walk. The article also includes a brief presentation of the history of mapping in Estonia in the confines of the modern state – the Swedish kingdom, Russian empire, military Germany, the Soviet Union, and Estonia. The role of individuals in creating landscapes in physical and representational form is a central issue in the case of Paldiski, based on which the more general concerns of ‘laying down the law’ and justice in landscape and society may be examined.

Low Prevalence of Asthma in Westernizing Countries—Myth or Reality? Prevalence of Asthma in Estonia—A Report from the “FinEsS” Study

Aim: The aim of this study was to examine the prevalence of asthma among adults in Estonia by using different diagnostic methods and criteria for the disease. Methods: In 1995–1996, a postal questionnaire was randomly distributed in three areas of Estonia to a representative sample of 22,579 subjects aged 15–64 years. The participation rate was 78%. A clinical follow-up study including structured interview, skin prick test, lung function, and methacholine test, was performed from 1997 to 2000 among randomly selected responders to the postal questionnaire. Of 2676 subjects, 53% participated. Results: The prevalence of physician-diagnosed asthma for the postal questionnaire (PQ) was 2.7%, and in the same subjects for the structured interview (SI) 3.8%. Respiratory symptoms, except recurrent wheeze, were more common in the SI than PQ. Combinations of symptoms, except wheezing with breathlessness apart from cold, were more prevalent in the PQ responders. The prevalence of asthma defined by different symptom combinations varied from 5.4% to 8.2%. Among responders, 71–87% demonstrated bronchial hyperreactivity defined as methacholine reactivity ≤ 8 mg/mL. The symptom combinations used as surrogate variables for asthma were strongly associated with a positive skin test. Conclusion: The low prevalence of physician-diagnosed asthma probably reflects a considerable underdiagnosis of asthma in Estonia. Disease criteria for asthma based on symptom combinations together with hyperreactivity yielded a prevalence of 5%–8%, which is similar to the prevalence of asthma among adults in neighboring Western countries.

“One Should Not Forget One's Mother Tongue”: Russian-Speaking Parents' Choice of Language of Instruction in Estonia

This exploratory study identifies factors affecting parental choice of language of instruction, based on semistructured interviews with 16 Russian-speaking parents in three urban areas of Estonia. We investigated three different types of language programs: Russian schools, which provided education in the children's first language; Estonian schools, which provided education in the children's second language; and Russian–Estonian bilingual programs, which functioned as separate classes within Russian schools. Our interviews with parents revealed four basic types of orientation toward language and culture. We have labeled these orientations multicultural (appreciating or feeling comfortable with many languages and cultures), Russocentric (feeling most comfortable with Russian culture and/or seeing Russian language and culture as superior), bicultural (having familiarity with and/or interest in both languages and cultures, or cultural neutrality), and Estoniocentric (having a strong desire to belong to the Estonian cultural and language group). These orientations correspond to parents' choice of language of instruction for their children, suggesting that choice of school language has different meanings for parents with varying culture and language identifications.

Calculations on the energy and nutrient content of kindergarten menus in Estonia

Objective: To evaluate kindergarten menus in the frame of the National Health Programme for Children in Estonia in order to guarantee optimal food intake for children. Design: Five kindergarten menus were calculated in Tallinn and in a rural area in Estonia from February 1999 to December 2001, including both Russian and Estonian kindergartens with more than 700 children. The study was conducted using a Micro-Nutrica programme, the database with 700 foodstuffs and 900 ready-to- eat meals, with 56 characteristics of nutrients. Results: Estonian kindergarten menus provided the recommended amount of food energy. The percentage of energy derived from saturated fatty acids was too high and that from polyunsaturated fatty acids too low. There was an insufficient content of vitamins C and D and dietary fibre in all kindergarten menus, and the content of other micronutrients differed from menu to menu. Conclusions: The energy content of menus on different days should be ba lanced. There is a need to alter the balance of carbohydrates and fats in favour of increasing starch and lowering saturated fats. Insufficient amount of vitamins C and D in meals should be supplemented by adding casseroles, fruit juices and fish dishes. A correction should be made in favour of calcium and iron, and for a lower sodium content. Keywords: children’s nutrition; daily kindergarten menus; energy and nutrient content; Micro-Nutrica

Bumblebee communities as an indicator for landscape monitoring in the agri-environmental programme

The current article focuses on the possibilities of applying bumblebees as one of the biodiversity indicators in the monitoring and evaluation of the Estonian Agri-Environmental Programme (AEP) at landscape level. The need for agri-environmental indicators arises, at least partially, because the desired state of the environment sought by policy makers may not be directly observable. To develop agri-environmental measures favourable to landscape quality, it is necessary to know more about the relationship between landscape structure and composition and the number of different species. This study tested the relationship between the data sets of landscape elements and bumblebee communities from 11 agricultural areas in Estonia. The localities were divided into two groups: intensively used agricultural areas (IA) (the percentage of arable land was >65%) and less intensively used agricultural areas (LIA) (the percentage of arable land was <45%). The following elements of landscape structure were analysed: buffer zones narrower than 5 m and wider than 5 m, ecotones between cultivated land and broad-leaved forests, ecotones between cultivated land and mixed or coniferous forests, ditches and brooks, fallow land, mixed forests, coniferous forests, broad-leaved forests, bushes, wetlands, cultivated grasslands, pastures, legumes, arable land, semi-natural grasslands. Fifteen bumblebee species were recorded in LIA and 13 in IA. The most widely distributed and abundant species were Bombus lucorum, Bombus pascuorum and Bombus lapidarius. These species dominated in both types of agricultural area. Two species, Bombus jonellus and Bombus hypnorum were found only in LIA. Principal component analysis (PCA) was applied to the landscape elements and the bumblebee species found. Results showed that there was a significant co-structure between the data sets of landscape elements and bumblebee communities. The most important landscape features that correlated with the distribution of the bumblebee species were the ecotone length between cultivated land and forests, and the size of the area covered with mixed forests and wetlands.

Diversity of Helicobacter pylori genotypes among Estonian and Russian patients with perforated peptic ulcer, living in Southern Estonia

To compare the genomic variation of Helicobacter pylori in samples obtained from patients with perforated peptic ulcer, living in the same area of Estonia but belonging to different nationalities, 50 non-consecutive patients (32 Estonians and 18 Russians) admitted in the Tartu University Hospital in 1997–1999 were studied. Gastric samples of antral mucosa were obtained during operation and analysed histologically and with PCR for detection of different genotypes of H. pylori ( cagA and vacA s and m subtypes). Among the 50 perforated peptic ulcer patients with histologically proven H. pylori colonisation no sample of gastric mucosa showed the s1b subtype of the vacA gene. The perforated peptic ulcer patients were mainly infected with cagA (82%) and s1 (98%) genotypes of H. pylori. The distribution of s1a/m1, s1a/m2 and s2/m2 subtypes of vacA genes was statistically different in Estonian and Russian patients ( P<0.05). In conclusion differences in the distribution of vacA s and m subtypes of H. pylori were revealed between Estonian and Russian patients with perforated peptic ulcer from Southern Estonia.

Diversity of Helicobacter pylori genotypes among Estonian and Russian patients with perforated peptic ulcer, living in Southern Estonia.

To compare the genomic variation of Helicobacter pylori in samples obtained from patients with perforated peptic ulcer, living in the same area of Estonia but belonging to different nationalities, 50 non-consecutive patients (32 Estonians and 18 Russians) admitted in the Tartu University Hospital in 1997-1999 were studied. Gastric samples of antral mucosa were obtained during operation and analysed histologically and with PCR for detection of different genotypes of H. pylori (cagA and vacA s and m subtypes). Among the 50 perforated peptic ulcer patients with histologically proven H. pylori colonisation no sample of gastric mucosa showed the s1b subtype of the vacA gene. The perforated peptic ulcer patients were mainly infected with cagA (82%) and s1 (98%) genotypes of H. pylori. The distribution of s1a/m1, s1a/m2 and s2/m2 subtypes of vacA genes was statistically different in Estonian and Russian patients (P<0.05). In conclusion differences in the distribution of vacA s and m subtypes of H. pylori were revealed between Estonian and Russian patients with perforated peptic ulcer from Southern Estonia.

ORIGIN AND AREA OF SETTLEMENT OF THE FINNO-UGRIAN PEOPLES

Hitherto the opinions held by N. A. Castren and E. N. Setala about the origin and the extension of settlement areas of the Finno-Ugrians, which were principally based upon the results of linguistic studies, had been acknowledged. Accordingly, the original home of the Finno-Ugrians could have been situated somewhere at the bend of the middle Volga and along the banks of its tributaries. From there a part of them gradually turned westwards, after the Ugrian branch had migrated off elsewhere, yet some tribes stayed behind at intervals. The tribes migrating to the west separated from the groups left behind, and so linguistic distinctions emerged. Finally, about the time of the birth of Christ, a part of the so-called Baltic Finns arrived in the Baltic area. Based on archaeological finds, however, this colonisation of the Baltic area was found to have taken place considerably earlier--even within the first millenary B.C. Supported by numerous prehistoric discoveries we are now able to distinguish the movements of the tribes at that time and thereby establish quite new and also different opinions concerning the origin and the extension of the settlement areas of the Finno-Ugrians. In this outline I can only render a short summary of the synthesis of the examined prehistoric material. In doing so we cannot just restrict ourselves to the real question, but our contemplation must begin with the terminal phase of the glacial period. At that time our whole country, or better the whole of Balto-Scandinavia, was still covered with ice. The southern border of this glacial area extended from Denmark to the present-day Russia, covering northern Germany, East Prussia, Lithuania, and Latvia, as may be seen in Fig. 3. This period is called Dani-Glacial, and dates back about 18,000 to 20,000 years. It was the end of the early Stone Age when men chiefly lived from hunting reindeers. Reindeer herds used to stay near the borders of the ice region and immediately migrated farther north when the receding ice had released new tracts of land in the course of centuries and millenaries. Thus the hunters of that time, too, settled not very far from the ice borders and migrated farther north into those new areas offered to them by nature. The end of the early Stone Age showed an abundant, highly developed and many-sided culture (Fig. 1, 2) by the Cro-Magnon man or an original European who was already very much similar to the present-day man in his development. These were the reindeer hunters who followed the receding ice to the north. The harpoons and notched spearheads, as the illustrations show, appeared towards the end of the early Stone Age (towards the end of the Magdalenian). The area of common usage was western and central Europe, but did not reach beyond Moravia in the east. From these districts the harpoons were brought farther north by the fishermen-hunters. [FIGURE 1 OMITTED] [FIGURE 2 OMITTED] By 10,000-8,000 B.C. ice had already disappeared from the area of Estonia. Finland was still partly covered with ice, which extended from there to central Sweden, whereas Norway was almost completely covered with ice (Fig. 3). At that time a harsh tundra-climate prevailed in south Scandinavia as well as in the eastern Baltic countries, permitting a scanty vegetation of pigmy birches, bilberry-bushes, etc., among which--almost exclusively - reindeer herds grazed. From this time there are no vestiges of men to be found in Estonia, though reindeers already lived there according to discoveries. The earliest traces of men have been found in the Latvian area, though it may be supposed with certainty that men had already settled in Estonia too. [FIGURE 3 OMITTED] The ice receded more and more quickly. By 7,000 B.C. it only covered the Scandinavian mountains (Fig. 3): the ice frontier then almost corresponded to that of the Post-Glacial period. The climate had become perceptibly milder. …

Calcium, snails, and birds: a case study

Abstract. Recent studies have shown that wild birds breeding in acidified areas have difficulties with obtaining sufficient calcium for their eggshells, and that the cause of it is the shortage of land snails. Many birds have to search for Ca-rich snail shells on a daily basis during egg production. Molluscs depend on litter calcium, which has decreased due to acidification of the environment. Calcium limitation may be a widespread phenomenon also in non-acidified, naturally Ca-poor areas. The problem is that while in the latter areas the time for development of specific adaptations may have been sufficient, then in acidified areas, on the contrary, calcium shortage is a recent phenomenon. Therefore, since the extent of calcium limitation in non-acidified areas is hard to derive from observational data, experimental approach is needed. We provide experimental evidence that specific calcium deficit does affect reproductive traits also in the birds breeding in naturally base-poor habitats. Our study was conducted in a heterogeneous woodland area in Estonia containing deciduous forest patches as well as base-poor pine forest with low snail abundance. Ca supplementation, using snail shell and chicken eggshell fragments, was carried out for pied flycatchers and great tits. Extra calcium affected positively several reproductive traits like egg volume and eggshell thickness, start of breeding, and fledglings&amp;amp;#146; parameters. The negative relationship between calcium availability and lay-date suggests that birds adjust their breeding tactics to conditions of Ca deficiency, for example, by postponing laying.

The role of soil conditions in fine root ecomorphology in Norway spruce (Picea abies (L.) Karst.)

The present study is an attempt to investigate the pattern of morphological variability of the short roots of Norway spruce (Picea abies (L.) Karst.) growing in different soils. Five root parameters – diameter, length and dry weight of the root tip, root density (dry weight per water-saturated volume) and specific root area (absorbing area of dry weight unit) were studied with respect to 11 soil characteristics using CANOCO RDA analysis. The investigation was conducted in seven study areas in Estonia differing in site quality class and soil type. Ten root samples per study area were collected randomly from the forest floor and from the 20 cm soil surface layer. Eleven soil parameters were included in the study: humus content, specific soil surface area, field capacity, soil bulk density, pH (KCl and H2O dilution's), N and Ca concentrations, Ca/Al and C/N ratios, and the decomposition rate of fine roots (<2 mm dia.). Root morphological characteristics most strongly related to the measured soil characteristics in the different sites were specific root area, root density and diameter of the short roots, the means varying from 29 to 42 m2 kg−1, from 310 to 540 kg m−3 and from 0.26 to 0.32 mm, respectively; root density being most sensitive. The most favourable site and soil types resulting in fine roots with morphological characteristics for optimizing nutrient uptake (e.g. low short root density and high specific root area) were Umbric Luvisol (Oxalis), Dystric Gleysol (Oxalis) and Gleyic Luvisol (Hepatica). These soil types correspond to highly productive natural forest stands of Norway spruce in Estonia. All measured soil variables explained 28% of total variance of the root characteristics. The most important variables related to root morphology were the humus content, field capacity and specific soil surface area.

Examination of ras (P21) proteins in plasma from workers exposed to benzene emissions from petrochemical plants and healthy controls

Exposure of workers to benzene and polyaromatic hydrocarbons has been documented to be at relatively high levels in the production of benzene and in the coking process at a petrochemical plant in the oil shale area in Estonia. Altogether 97 plasma samples from workers and 40 from unexposed matched referents from two samplings in different seasons were analyzed for the presence of ras (P21) proteins; of the workers 50 were exposed to benzene in the benzene production plant and 47 to polyaromatic hydrocarbons and benzene in a cokery. Proteins were separated by gel electrophoresis, transferred to a nitrocellulose membrane by Western blotting and detected by chemiluminescence, using a monoclonal antibody as the primary antibody. There were no statistically significant differences between the exposed and the referent groups. The results are thus in keeping with the lack of exposure related cytogenetic effects for this same workforce.

SEA-LEVEL RISE IMPACT ON COASTAL AREAS OF ESTONIA

Due to long coastline (3,794 km in total) and extensive low-lying coastal areas, global climate change through sea-level rise will strongly affect the territory of Estonia. A number of valuable natural ecosystems (both, marine and terrestrial) containing rare plant communities often rich in species, but also suitable breeding places for birds will be in danger. Most sandy beaches high in recreative value will disappear. However, isostatic land uplift and location of coastal settlements at a distance from the present coastline reduce the rate of risk. Four case study areas characterizing all the shore types of Estonia have been selected for sea-level rise vulnerability and adaptation assessment. Preliminary results and estimates of vulnerability to 1.0 m sea-level rise by 2075 for two case study areas – Hiiumaa, West-Estonian Archipelago and Parnu-Ikla, south-western coast of the mainland – are presented in this paper.