Integrated palaeoecological and historical data in the service of fine-resolution land use and ecological change assessment during the last 1000 years in Rõuge, southern Estonia

Aims Our aim is to reconstruct decadal scale development of historical landscapes during the last 1000 years by means of fossil pollen analysis of annually laminated lake sediments, and detailed historical maps and documents. Location Lake Rõuge Tõugjärv (Estonia), a small lake with annually laminated lake sediments situated in a dense prehistoric setting. Methods The chronology of the palaeodata is based on the annual laminations supported by AMS ¹⁴C and ²¹⁰Pb dating and ¹³⁷Cs, ²⁴¹Am, and spheroidal carbonaceous particle marker horizons. The time‐scale and resolution allows fine sampling (the pollen samples generally comprise 3.5 years) and vegetation change reconstruction. Relevant source area of pollen (RSAP) of the lake was estimated, and the statistical zonation, rate of change, palynological richness, and DCA and PCA ordinations were generated on the basis of the pollen data. The historical calibration data set (maps, numerical information on population, domestic stock, farmland division, etc.) is based on archival material preserved in the Estonian Historical Archives. Results The topmost part (0–180 cm) of the sediment column of Lake Rõuge Tõugjärv, covering the last 1000 years, is visibly laminated carbonaceous gyttja. The varve chronology extends from ad 2000 to ad 1339, with a cumulative ± 9‐year error estimate. Beyond this the chronology is extrapolated using the ¹⁴C date and varve age–depth estimations. The simulation of the RSAP of Lake Tõugjärv shows that the major portion of the pollen loading originating from local vegetation is derived from plants growing within 2000 m of the sampling site. The pollen record divides into five statistically significant subgroups, which fall on the PCA plot into three clusters reflecting the general openness–closedness of the landscape. During the period between ad 1000 and 1200 (RT 1) the Rõuge area was generally wooded with birch, spruce and pine forests. The advancement of extensive farming gradually opened up the landscape between ad 1200 and 1650 (RT 2 and RT 3). The maximum openness of the landscape was reached between ad 1650 and 1875 (RT 4), with the most open period in the late eighteenth century. Historical maps from 1684 and 1870–99 and available quantitative data on population, domestic stock, farmland division, etc. show the same trend. The pollen data covering the last 125 years, and maps from 1935 and 1995, show the reduction of arable land in RSAP of the lake under investigation and the reduction of open land to an extent comparable with the end of the seventeenth century. Main conclusions The formation and development of the cultural landscape at Rõuge over the last 1000 years is characterized by rapid changes in floristic richness and rates of vegetation change attributed to certain historic processes in the RSAP. Five phases of landscape and social development are clearly distinguished during the last 1000 years. The decadal scale vegetation response to human‐induced forcing agrees with historical maps and documents and could be used for past landscapes prior to the period with solid historical data.     

Occurrence of Giant Borings of Osprioneides kampto in the Lower Silurian (Sheinwoodian) Stromatoporoids of Saaremaa,Estonia

The distribution of Osprioneides is more environmentally limited than that of Trypanites in the Silurian of Baltica. Osprioneides probably occurred only in large hard substrates of relatively deepwater muddy bottom open shelf environments. Osprioneides were relatively rare, occurring in 4.7% of all stromatoporoid specimens in that environment, in contrast to small Trypanites-Palaeosabella borings, which occur in 88.4% of stromatoporoids and 88.9% of heliolitid corals. Osprioneides is reported only from the lower Sheinwoodian stromatoporoids of the exposed Silurian of Saaremaa (Wenlock to Pridoli). Osprioneides borings probably played a minor role in the general bioerosion in the Silurian of Baltica.     

Nationalizing states revisited: projects and processes of nationalization in post-Soviet states

This paper analyses Estonia, Latvia, Ukraine and Kazakhstan as nationalizing states, focusing on four domains: ethnopolitical demography, language repertoires and practices, the polity and the economy. Nationalizing discourse has figured centrally in these and other ‘post-multinational’ contexts. But nationalizing projects and processes have differed substantially across cases. Where ethnonational boundaries have been strong, quasi-racial and intergenerationally persistent, as in Kazakhstan, nationalization (notwithstanding inclusive official rhetoric) has served primarily to strengthen and empower the core nation. Where ethnonational and linguistic boundaries have been blurred and permeable, as in Ukraine, nationalization has worked primarily to reshape cultural practices, loyalties and identities, thereby in effect redefining and enlarging the core nation. Where boundaries have been strong, yet show signs of being intergenerationally permeable, as in Estonia and Latvia, nationalization was initially oriented towards protecting, strengthening, and empowering the core nation as a sharply bounded collectivity, but has subsequently become more assimilationist and culturalist.     

Half a century of oligochaete research in Estonian running waters

About 51500 specimens from 1542 samples, collected over the years 1954–1975 and 1986–1999 in different running water bodies throughout Estonia, were identified. Tubificidae prevailed in the material, with Limnodrilus hoffmeisteri forming about 40%. This species was followed by the tubificids Tubifex tubifex, Potamothrix hammoniensis, Psammoryctides barbatus, L. udekemianus and Spirosperma ferox, the naidid Stylaria lacustris, and the lumbriculid Stylodrilus heringianus. Two main ecological assemblages were distinguished: the pelophilous assemblage, dominated by L. hoffmeisteri, and the psammophilous one, where usually P. barbatus was dominant. The relationships between different species and the chemical parameters of water were usually weak but in contrast, correlated well with sediment preferences. In organically enriched reaches, L. hoffmeisteri usually dominated. The fauna of the streams of the islands was poorer in species due to their small size rather than geographical isolation. Some recent antropochorous Ponto-Caspian invaders have only reached the lowermost reaches of the two largest rivers. Some brackish water species were found in the mouth of the Pärnu River. No essential differences were found between the comparable sets of oligochaete samples collected in 1954–1975 and 1987–1997 in the Estonian running waters.     

Macrozoobenthos of Lake Verevi

An overview on studies of macrozoobenthos in the small, hard-water, stratified and hypertrophic Lake Verevi (South-Eastern Estonia) is given. The list of macroinvertebrates comprises at least 105 taxa. In the open water habitats, the biomass and abundance of macrozoobenthos (except the phantom midge Chaoborus flavicans) was rather constant beginning from the epilimnion up to the upper hypolimnion (depth 2–4 m), but very low in the lower hypolimnion (depth 6 m), which was inhabited mainly by Chaoborus. Comparison with long-term reference data from other Estonian lakes, belonging to similar limnological types, indicated that the total biomass and abundance (without Chaoborus) in the profundal of Verevi were very low.     

Revision of Hyolitha from the Ordovician of Estonia

Topotype specimens of the Middle OrdovicianHyolithes acutus Eichwald, 1840, which is the type of the genus that lent its name to a family, order, class, and even phylum according to some, andH. latus Eichwald, 1860 allow that genus and those species to be firmly established on a sound, morphologic basis. In addition, preservation of the types ofHyolithes striatus Eichwald, 1860 is sufficiently good to warrant reassignment toDorsolinevitus Syssoiev, 1958. In contrast, the type ofH. insularis Eichwald, 1860 is incompletely preserved, and this species is not recognizable beyond the type material. The concept of the family Hyolithidae is revised to more closely conform to the morphology ofHyolithes, with authorship herein ascribed toSyssoiev (1958) rather than toNicholson (1872). The stratigraphic distribution of these taxa suggests thatHyolithes as defined herein first appears in the Middle Ordovician, but extends into at least the Lower Devonian, as suggested by two species from the Barrandian region of the Czech Republic. Their geographic distribution further re-enforces the notion of two distinct paleobiogeographic provinces based on hyoliths, a Mediterranean province and Baltic province, with almost no mixing of hyolith faunas during the Ordovician.      

The effects of climate change on the phenology of selected Estonian plant, bird and fish populations

This paper summarises the trends of 943 phenological time-series of plants, fishes and birds gathered from 1948 to 1999 in Estonia. More than 80% of the studied phenological phases have advanced during springtime, whereas changes are smaller during summer and autumn. Significant values of plant and bird phases have advanced 5–20 days, and fish phases have advanced 10–30 days in the spring period. Estonia’s average air temperature has become significantly warmer in spring, while at the same time a slight decrease in air temperature has been detected in autumn. The growing season has become significantly longer in the maritime climate area of Western Estonia. The investigated phenological and climate trends are related primarily to changes in the North Atlantic Oscillation Index (NAOI) during the winter months. Although the impact of the winter NAOI on the phases decreases towards summer, the trends of the investigated phases remain high. The trends of phenophases at the end of spring and the beginning of summer may be caused by the temperature inertia of the changing winter, changes in the radiation balance or the direct consequences of human impacts such as land use, heat islands or air pollution.     

The life cycle assessment management tool for technologies in eastern Europe: why and how

The knowledge and use of western-based environmental management tools like LCA (life cycle assessment) in Eastern Europe is very low. Discussions about introducing environmental management systems and taking care of environmental consequences of producing processes are very relevant now in Eastern European countries that want to become members of the European Union and to introduce their goods onto the international market. In this paper, the problems connected to introducing LCA based environmental management systems and Eco-Labeling in Eastern European countries are described. The poor financial condition of national sciences in Estonia does not appear to be the main problem. A brief overview of the development and current status of LCA research in Denmark, Finland and Japan is presented. Solutions to current problems are discussed, and experiences gained during conducting LCA research on oil shale energy production in Estonia are presented.     

Cold hardiness in the pre‐imaginal stages of the great web‐spinning pine‐sawfly Acantholyda posticalis

相似文献   

The Arrival of Siberian Ancestry Connecting the Eastern Baltic to Uralic Speakers further East

Download : Download video (141MB)