Estonian Journal of Ecology最新文献

{"title":"Species composition and structure of vascular plants and bryophytes on the water level gradient within a calcareous fen in North Estonia.","authors":"M. Ilomets, L. Truus, R. Pajula, K. Sepp","doi":"10.3176/ECO.2010.1.02","DOIUrl":"https://doi.org/10.3176/ECO.2010.1.02","url":null,"abstract":"We examined the relationship between the composition and structure of vegetation and hydrology and microtopography within the Paraspollu calcareous-rich fen (North Estonia). Species composition, depth to groundwater level (+ 6 to - 40 cm), pH (6.1-7.1), and electrical conductivity (220-840 µS cm -1 ) were recorded in 23 releves of 1 m 2 along transects over the site. The species composition and coverage of vascular plants depended on the extent of water level fluctuations and water conductivity, those of moss species additionally also on microtopography. A total of 44 bryophyte and 57 vascular plant species were identified, including 14 protected and rare species. Nonmetric multidimensional scaling and the Monte Carlo test were used to describe compositional variation and identify significant habitat variables separately for vascular plant and bryophyte species. The relationship between the species composition of field and surface layers was nonsignificant. Three of the five assemblages distinguished by two-way cluster analysis, Carex panicea-Schoenus ferrugineus-Drepanocladus cossonii, Phragmites australis-Calliergonella cuspidata, and Molinia caerulea-Carex davalliana, represent the calcareous tufa-forming fen type. The other two are distributed on the moderately drained part of the fen. The number and coverage of rich fen species decreased sharply as the coverage of M. caerulea exceeded the 30% level and seasonal fluctuation of water level was over 25 cm.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"188 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132256953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lynx acceptance in Poland, Lithuania, and Estonia","authors":"L. Balčiauskas, M. Kazlauskas, T. Randveer","doi":"10.3176/ECO.2010.1.04","DOIUrl":"https://doi.org/10.3176/ECO.2010.1.04","url":null,"abstract":"Lynx acceptance in NE Poland, Lithuania, and Estonia was assessed by using a questionnaire survey. Regions under assessment differed in lynx numbers, population dynamics, and protection status. We examined if public opinion was related to the species conservation status and population size. In the northern part of the investigated territory, respondents were the most realistic as to the knowledge of lynx presence in the region and they accepted better lynxes close to their home. In the southern part, respondents were more positive about lynx number increase; in the north, maintaining current numbers was preferred. The importance of wilderness for respondents was increasing southwards. Thus, the south-north gradient on the lynx acceptance in NE Poland, Lithuania, and Estonia followed the species situation.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122838659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Autumn Swarming of the Pond Bat Myotis Dasycneme at Hibernation Sites in Latvia/Tiigilendlase Myotis Dasycneme Sugisene Parvlemine Talvituspaikade Juures Latis","authors":"V. Vintulis, J. Šuba","doi":"10.3176/ECO.2010.1.06","DOIUrl":"https://doi.org/10.3176/ECO.2010.1.06","url":null,"abstract":"Capturing of swarming bats was carried out at five hibernation sites in Latvia in 2005- 2007. In total 436 pond bats Myotis dasycneme were caught and marked with forearm rings. The most prominent swarming was observed in August-September, which corresponds with relevant results from other countries. Most bats caught were adults, with the domination of adult males. Spearman's rank correlation showed statistically significant changes in numbers of different age and sex groups of bats during the swarming season. Behavioural observations of bats and recaptures of males indicate that possibly the main reason for the swarming activity of pond bats is mating.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129414008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New data on the distribution of the barbastelle bat Barbastella barbastellus in Latvia","authors":"G. Pētersons, V. Vintulis, J. Šuba","doi":"10.3176/ECO.2010.1.05","DOIUrl":"https://doi.org/10.3176/ECO.2010.1.05","url":null,"abstract":"The barbastelle bat Barbastella barbastellus is considered as a rare species with an unclear status of distribution. Only a few occasional winter records, single records, and a few observations during the autumn migration at the SW coast of Latvia have been reported in the literature. A survey on the distribution of the barbastelle bat was conducted in Latvia in 2006 and 2007. Ultrasound detectors with the time expansion sound transformation method, capture with mist nets, and inspection of cellars were used to find barbastelles. In total 20 new sites occupied by barbastelles were found in the central and northern parts of Latvia.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124901412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of vegetation performance on semicoke dumps of Kohtla-Järve oil shale industry, Estonia.","authors":"R. Vaht, M. Pensa, M. Sepp, A. Luud, H. Karu, T. Elvisto","doi":"10.3176/ECO.2010.1.01","DOIUrl":"https://doi.org/10.3176/ECO.2010.1.01","url":null,"abstract":"The performance of vegetation was assessed at semicoke dumping sites of Kohtla-Jarve oil shale industry in summers 2004 and 2006. The condition of tree species and the presence of herbaceous species were recorded in areas where the vegetation had been planted or had developed naturally. Betula pendula and Populus balsamifera were the most abundant tree species on the semicoke dumps covering 0.54 and 0.11 km 2 , respectively. Herbaceous vegetation had the highest coverage in stands dominated by Alnus glutinosa, but the species composition of herbs was homo- geneous under different tree species. Most of the herbaceous species were typical of wasteland areas (ruderal strategy type) or adapted to stressful conditions (stress-tolerant strategy type), including seven protected orchid species. The species composition of herbs was affected by the slope of the dump. Our results indicate that planting with Alnus glutinosa gives the best result for the reclamation of semicoke dumps as this tree species promotes the growth of herbaceous vegetation.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121630062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Records of horsehair worms (Nematomorpha) in Estonia, with description of three new species from the genus Gordius L.","authors":"A. Schmidt-Rhaesa, M. Prous","doi":"10.3176/ECO.2010.1.03","DOIUrl":"https://doi.org/10.3176/ECO.2010.1.03","url":null,"abstract":"INTRODUCTION About 300 species of horsehair worms (Nematomorpha) are known, about a third of them from Europe (Schmidt-Rhaesa 1997). The sampling within Europe is nevertheless far from being homogeneous and from some countries no or only a few records are known. This applies to Estonia as well as to the other Baltic states. There is only one brief report of some specimens determined as Gordius aquaticus Linnaeus, 1758 from Lake Vortsjarv (as lake Wirzjerw) by Muhlen & Schneider (1920). We report here several records, including the description of three new species of Nematomorpha from Estonia. It can be expected that the species reported here do not represent the entire diversity of species in the region. As only very fragmentary data are known from neighbouring countries, no estimates on the absolute number can be given here. Adult horsehair worms can be found in fresh water (with the exception of 5 species living in the sea), where they copulate and deposit eggs. From the eggs small larvae (around 100 [micro]m) hatch, which infect hosts. The exact life cycle is still unclear (Hanelt et al. 2005), but there is indication for a host change from aquatic to terrestrial hosts. The major development takes place within hosts such as carabid beetles, crickets, or others. Adult worms have been shown to manipulate their hosts, making them enter water so that the nematomorph can emerge (Thomas et al. 2002). Important for the determination of Nematomorpha species are cuticular characters such as the structure of the body cuticle or cuticular structures in the male posterior end. Representatives of genera such as Gordionus, for example, have spines and bristles in characteristic distribution patterns on the ventral side of the male posterior end (see e.g. Fig. 1C). In contrast, representatives of the genus Gordius are comparably poor in cuticular structures. Characteristic of the genus Gordius is a semicircular cuticular fold, the postcloacal crescent (see e.g. Fig. 2A), but bristles are much finer and fewer compared to Gordionus. Some of such bristles as well as the fine structure of the superficially smooth body cuticle might have been overlooked in earlier investigations that did not use scanning electron microscopy. Both genera, Gordius and Gordionus, are comparably species-rich, with about 60 and 46 described species, respectively. Both are distributed almost worldwide, but Europe appears to host most species, including abundant ones such as Gordius aquaticus Linnaeus, 1758 and Gordionus violaceus (Baird, 1853). MATERIALS AND METHODS Specimens reported here were collected in different locations in Estonia between 1971 and 2009 (in addition one record from Russia). Investigation of the specimens by scanning electron microscopy (SEM) took place in the Zoological Museum of the University Hamburg, Germany. Specimens were preserved in ethanol. Pieces of the cuticle and/or the posterior end were prepared for SEM. Pieces were dehydrated in an increasing ethano","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122034443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crustacean invasions in the Estonian coastal sea","authors":"K. Herkül, J. Kotta, T. Püss, L. Kotta","doi":"10.3176/ECO.2009.4.06","DOIUrl":"https://doi.org/10.3176/ECO.2009.4.06","url":null,"abstract":"INTRODUCTION Together with habitat loss and climate change, invasions of nonindigenous species are one of the most serious threats to global biodiversity. This human-aided process has initiated significant, unpredictable, and irreversible changes to both the abiotic and the biotic environment and has caused severe economic damage in a variety of waterbodies worldwide (e.g. Canton, 1996; Vitousek et al., 1997; Sala et al., 2000). Concurrently with this global trend several new crustacean species have also been found in the Estonian coastal sea in recent years. The gammarid amphipod Gammarus tigrinus Sexton originates from the North American coast of the Atlantic Ocean. The species was introduced to Europe probably in ballast water and was first discovered in England in 1931 (Chambers, 1977). Although G. tigrinus was found in the Baltic Sea already in 1975, its significant range expansion started in the 1990s (Jazdzewski et al., 2002, 2005; Szaniawska et al., 2003). In the northern Baltic Sea G. tigrinus was first found in the northern Gulf of Riga (Herkul et al., 2006) and the northern Gulf of Finland in 2003 (Pienimaki et al., 2004). In 2005, G. tigrinus was found in the Neva Estuary, the easternmost part of the Gulf of Finland (Berezina, 2007). This species has caused a significant decrease in the diversity and density of native amphipods in the southern Baltic Sea (Grabowski et al., 2006) and Estonian coastal sea (Kotta et al., 2006; Orav-Kotta et al., 2009). The amphipod Chelicorophium curvispinum (Sars) originates from large rivers connected to the Black Sea and the Caspian Sea. It was found in the Baltic Sea already in the 1920s (Bij de Vaate et al., 2002). The species invaded to the Baltic and North seas through rivers and canals attached to the hulls of ships and in ballast water. Regardless of its long invasion history in the Baltic Sea, C. curvispinum was not found in the northern Baltic until 2005 when it was detected in the eastern part of the Estonian coast of the Gulf of Finland (Herkul & Kotta, 2007). In the next year, 2006, C. curvispinum was found in Luga Bay, Russia (Malyavin et al., 2008). Similarly to C. curvispinum, the gammarid amphipod Pontogammarus robustoides (Sars) originates from the lower reaches of Ponto-Caspian rivers and from brackish and freshwater lakes around the Black Sea (Bij de Vaate et al., 2002). In 1960-1961, the species was intentionally introduced into the Kaunas Water Reservoir on the Nemunas River, Lithuania (Bij de Vaate et al., 2002; Gumuliauskaite & Arbaciauskas, 2008). It successfully spread in the Nemunas drainage system including the Curonian Lagoon of the Baltic Sea. In 1999 P. robustoides was first found in Neva Bay, the easternmost part of the Gulf of Finland (Panov et al., 2003) and in 2006, in Lake Ladoga (Kurashov & Barbashova, 2008). In 2006 the species was recorded for the first time in the Estonian coastal sea. Similarly to G. tigrinus, P. robustoides has a potential to reduce the diversit","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129866164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of the Phytoplankton Productivity in Three Estonian Lakes/ Futoplanktoni Produktiivsuse Hindamine Kolmes Eesti Jarves","authors":"T. Kauer, H. Arst, T. Nõges, L. Tuvikene","doi":"10.3176/ECO.2009.4.05","DOIUrl":"https://doi.org/10.3176/ECO.2009.4.05","url":null,"abstract":"INTRODUCTION Light provides the energy necessary for the transformation of inorganic matter into organic matter by the planktonic algae and all other photoautotrophic plants. Primary production is the direct product of photosynthesis, and primary productivity is the sum of all photosynthetic rates in an ecosystem (Fee, 1998). Information on the primary production enables to improve the understanding of food web relationships in aquatic ecosystems. Because of changing light conditions, primary production has a pronounced diel pattern. In order to acquire integrated results over longer time periods (days, months, years), many consecutive measurements of instantaneous photosynthesis rate should be carried out and integrated. In some studies (Joniak et al., 2003; Yoshida et al., 2003; Forget et al., 2007) the values of daily primary production integrated over the photic zone were estimated from in situ incubations. However, such approach gives reliable results only in clear waters, while in highly productive waters incubation cannot be performed during a long period (e.g. from morning to evening) as part of the [sup.14]C-label gets lost from the cells during long-term incubation due to respiration of photosynthetic products (Lancelot & Mathot, 1986) and release of extracellular products (holler Jensen, 1985). Bio-optical model calculations could provide an alternative to the time-consuming 14C method. Several studies estimate primary production from light intensity and abundance of phytoplankton pigments (cited in Arst et al., 2008a). In cases the processes of interest occur on a longer time-scale, it is common to ignore diurnal variations and use mean daily photosynthetically available irradiance (PAR) to force models of primary producers. Widely used methods include those where the dependence of photosynthesis on available light is expressed by an equation containing two parameters: the initial slope [[alpha].sup.[[beta] and the assimilation number [P.sup.B.sub.m] (Sathyendranath et al., 1989). In these models also data on the vertical profiles of the photosynthetically active radiation (PAR) (Einst [h.sup.-1] [m.sup.-2]) are needed. This is a rather complicated way and gives results on the basis of radiation integrated over the PAR region. For reliable description of primary production profiles, however, it is preferable to use a 'spectral approach', in which the model is based on spectral data of underwater quantum irradiance and absorption coefficients of phytoplankton (Sathyendranath et al., 1989; Smith et al., 1989; Schofield et al., 1990; Kyewalyanga et al., 1992; Kirk, 1994; Sosik, 1996; Arst et al., 2006, 2008a). Two versions (spectral and integral) of a semi-empirical model for calculation of the vertical profiles of primary production in lakes were elaborated by Arst et al. (2008a). The main difference between the models resides in the data on underwater irradiance (spectral or integral). Quantification of these models was performed using","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123606887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term changes in a northern Baltic macrophyte community","authors":"A. Kovtun, K. Torn, J. Kotta","doi":"10.3176/ECO.2009.4.03","DOIUrl":"https://doi.org/10.3176/ECO.2009.4.03","url":null,"abstract":"Over the last 45 years significant changes in the floristic composition, distribution pattern, and dominance structure of phytobenthos were observed in Haapsalu Bay. Although the species composition of macroalgae did not change much over the course of this study, we observed notable changes in the community structure, i.e. algal shares. Some species, e.g. Tolypella nidifica, disappeared, other species such as Chara connivens and Chara baltica appeared for the first time in the study area. Besides, many prevailing species were relocated within the observed area over the course of the study. Another distinct feature of the recent years is that the vegetation had no dominant species. In general decadal variability exceeded yearly variability. There was no single abiotic variable that exerted major influence on phytobenthic communities. Instead we observed a combined effect of multiple environmental variables on phytobenthos communities. This study indicated that the changes in phytobenthic communities in Haapsalu Bay over the last 45 years were mainly due to large-scale weather patterns that determined regional salinity and ice conditions. Salinity sets the dominance pattern of phytobenthic species of freshwater and marine origin within communities. The intensity of ice scrape in turn created new unvegetated substrate and determined the overall phytobenthic cover in the study area. Within these large-scale patterns exposure, depth, and spatial salinity gradients contributed to the variability of small-scale patterns of macrophyte communities. Regional nutrient loading had weak effects on macrophyte communities, mainly in interactions with local abiotic variables and regional weather patterns.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121835950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Response of benthic invertebrate communities to the large-scale dredging of Muuga Port","authors":"J. Kotta, K. Herkül, I. Kotta, H. Orav-Kotta, R. Aps","doi":"10.3176/ECO.2009.4.04","DOIUrl":"https://doi.org/10.3176/ECO.2009.4.04","url":null,"abstract":"The dynamics of benthic invertebrate communities in Muuga Bay was described in connection with large-scale dredging activities. The spatial extent and duration of the effects were assessed by multivariate analysis and spatial modelling. In general, dredging had moderate effects on benthic invertebrates both in space and time. Still, dredging resulted in an elevated biomass of bivalves, namely that of Macoma balthica. These bivalves were more impacted on flat bottoms compared to steep slopes.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124359514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}