Estonian Journal of Ecology最新文献

{"title":"Water Salinity and Benthic Macrophyte Communities Are the Key Variables Defining the Distribution Pattern of Benthic Faunal Assemblages in the Shallow Water Areas of the Gulf of Riga","authors":"J. Kotta","doi":"10.3176/ECO.2013.2.03","DOIUrl":"https://doi.org/10.3176/ECO.2013.2.03","url":null,"abstract":"The distribution of shallow water macrozoobenthic assemblages of the Gulf of Riga is analysed in relation to water current velocity, salinity, sediment type, ice disturbance, eutrophication, and benthic macrophytes. Salinity and benthic macrophyte communities described most of the variability in both the abundance and biomass structure of benthic invertebrates. In addition, surface chlorophyll a also contributed to the variability of benthic invertebrate biomass. Benthic invertebrate assemblages in the vicinity of the Daugava and Parnu rivers experience higher nutrient loading and were therefore characterized by a lower species number and higher biomass of benthic suspension feeders. Benthic invertebrate communities in other regions of the Gulf of Riga were typical for the mildly disturbed areas of the northern Baltic Sea. Compared to the situation in the 1960s, no substantial increase in the abundance and biomass values of macrozoobenthos was observed as could be expected from the basinwide trend of increasing eutrophication.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114828939","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":"Humus cover and its fabric depending on pedo- ecological conditions and land use: an Estonian approach to classification of humus forms","authors":"R. Kõlli, I. Tamm","doi":"10.3176/ECO.2013.1.02","DOIUrl":"https://doi.org/10.3176/ECO.2013.1.02","url":null,"abstract":"The fabric of humus cover (HC) may be very variegated, depending on local pedo-ecological conditions (origin and composition of deposits, topography, moisture regime, soil climate, plant cover composition). This multiplicity can be expressed by the HC types (or humus forms). On natural areas, where the HC is formed as a result of long-term equilibrated mutual influences of soil cover and plant cover, the fabric and properties of the HC may be used as an ecological indicator in the evaluation of the functioning character and intensity of the soil-plant system (or also the whole ecosystem). In Estonia, besides natural areas, the classifications of HCs are also elaborated for arable areas. Regardless of the profound changes in the fabric of the HC occurring with land-use change (from natural land to arable and vice versa), certain inherited properties are sustained in newly formed HCs. In this paper the fabric and properties (thickness, carbon and nitrogen stocks) of the main HC types (19 in total) are analysed and ecological aspects of HC formation are explained. Data on tree layer taxation, agro-chemical parameters of the soil cover, and ground vegetation productivity are presented with the HC types used as the ecological background. The relationships of soil cover with soil and forest site type are analysed against the background of soil matrix tables and ordination net of forest sites, respectively. Comparative analysis of the Estonian HC classification with the European Reference Base for humus forms (ERB) showed a relatively good correspondence of the Estonian classification of HC types with ERB's humus forms.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131374916","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":"Peat humic acid properties and factors influencing their variability in a temperate bog ecosystem","authors":"M. Kļaviņš, O. Purmalis, V. Rodinov","doi":"10.3176/ECO.2013.1.04","DOIUrl":"https://doi.org/10.3176/ECO.2013.1.04","url":null,"abstract":"Studies of the properties of soil organic matter are essential for understanding the humification reactions and soil diagenesis processes. The aim of this study is to analyse properties of peat and peat humic acids as well as factors influencing their variability. Humic acids isolated from an ombrotrophic bog peat profile were used as study objects. Relations among peat age, decomposition and humification degree, botanical composition, and properties of peat humic acids (elemental, functional composition, spectral characteristics) were studied. The variability of peat properties was found to be less significant than the differences in the properties of peat-forming living matter, which indicates the dominant impact of humification processes on the properties of peat. Correspondingly, the composition of peat humic acids was insignificantly affected by the differences in the composition of the precursor living organic material.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"97 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120819200","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":"Effectiveness of a shelterbelt in decreasing the level of inorganic elements in agricultural landscape","authors":"L. Szajdak, I. Życzyńska-Bałoniak","doi":"10.3176/ECO.2013.1.03","DOIUrl":"https://doi.org/10.3176/ECO.2013.1.03","url":null,"abstract":"Concentrations of calcium, magnesium, and carbon in inorganic compounds were measured in the groundwater crossing a shelterbelt. The differences among the concentrations of Ca, Mg, and C in inorganic compounds were attributed solely to the width of the shelterbelt. This biogeo- chemical barrier efficiently decreased the concentrations of chemical substances: the fall in the dry mass was 30-75%, in Ca 20-54%, in Mg 46-72%, and in C in inorganic compounds 58-71%.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123888919","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":"Distribution of organic carbon in humic and granulodensimetric fractions of soil as influenced by tillage and crop rotation","authors":"I. Liaudanskienė, A. Šlepetienė, A. Velykis, A. Satkus","doi":"10.3176/ECO.2013.1.05","DOIUrl":"https://doi.org/10.3176/ECO.2013.1.05","url":null,"abstract":"It is widely believed that soil disturbance by tillage is a primary cause of the loss of soil organic carbon (SOC) and that substantial SOC sequestration can be accomplished by conversion from conventional ploughing to reduced tillage. The objective of our study was to find alterations of the organic C content in soil humic and granulodensimetric fractions depending on soil tillage and crop rotation. The field experiment was carried out at the Joniskelis Experimental Station of the Lithuanian Institute of Agriculture on a drained clay loam Endocalcari-Endohypogleyic Cambisol (CMg-n-w-can). Two technologies - reduced tillage (RT) and conventional tillage (CT) - were compared in crop rotations with different proportions of overwintering and spring crops (0%, 25%, 50%, 75%, and 100% overwintering crops). The results of 2004-2006 are presented. Tillage had a greater influence than crop rotation on all soil C fractions. RT promoted the formation of all fractions of humic acids and FA1 and FA3 fractions of fulvic acids in the entire plough layer. Increasing the proportion of overwintering crops in the rotation to 100% tended to strengthen this effect. The C content in particulate organic matter (POM), light fraction (LF), and both clay-sized sub-fractions, expressed per unit mass of soil, significantly increased under RT in the top 15 cm of soil. The introduction of overwintering crops into the rotation and increasing their proportion had a significant positive influence on C content in POM and LF in the whole plough layer.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121993646","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":"Effect of Spring Oilseed Rape Crop Density on Plant Root Biomass and Soil Enzymes activity/Suvirapsi Taimiku Tiheduse Moju Taimejuurte Biomassile Ja Mulla Ensuumide Aktiivsusele","authors":"R. Čepulienė, A. Marcinkevičienė, R. Velička, R. Kosteckas, R. Pupalienė","doi":"10.3176/ECO.2013.1.06","DOIUrl":"https://doi.org/10.3176/ECO.2013.1.06","url":null,"abstract":"INTRODUCTION Soil health is the capacity of soil to function as a vital living system within ecosystem and land-use boundaries, to sustain plant and animal productivity and water and air quality, and to promote plant and animal health. To evaluate sustainability of agricultural practices, assessment of soil health using various indicators of soil quality is needed (Doran & Zeiss, 2000). Soil enzyme activity can be used as an indicator of soil quality for assessing the sustainability of agricultural ecosystems (Gianfreda et al., 2005; Roldan et al., 2005). Soil enzymes are important in catalysing innumerable reactions involved in the decomposition of organic matter, cycling of nutrients, and formation of organic matter structure (Bandick & Dick, 1999; Kandeler et al., 1999; Liu et al., 2008; Melero et al., 2008). Enzyme activity is closely related to other important indicators of biological activity: respiration intensity, nitrification ability, total amount of microorganisms, and even more strongly to soil organic carbon content, content of available [P.sub.2][O.sub.5] and [K.sub.2]O, soil acidity, and crop yield (Schimner & Sonnleitner, 1996; Bandick & Dick, 1999; Svirskiene, 1999; Liu et al., 2008). Enzymes that catalyse a wide range of soil biological processes offer a useful assessment of soil 'function', and common enzymes, such as urease and saccharase, fit into this category (Burns & Dick, 2005). Urease catalyses the hydrolysis of urea to C[O.sub.2] and N[H.sub.3], which is of particular interest because urea is an important nitrogen fertilizer. Urease is released from living and disintegrated microbial cells, and in the soil it can exist as an extracellular enzyme absorbed on clay particles or encapsulated in humic complexes (Nannipieri, 1994; Schimner & Sonnleitner, 1996). Saccharase catalyses the hydrolysis of saccharose into glucose and fructose and characterizes change processes of organic carbon compounds (Schimner & Sonnleitner, 1996). Several studies show that enzyme activities can be used as early indicators of changes in soil properties originated by soil and crop management practices such as tillage, crop rotation, residue management, and fertilization (Bandick & Dick, 1999; Kandeler et al., 1999; Acosta-Martinez et al., 2003; Roldan et al., 2005; Melero et al., 2008; Zakarauskaite et al., 2008; Wang et al., 2011). Acosta-Martinez et al. (2003) reported that the trends of the enzyme activities as affected by management depend on the soil, but in general crop rotation and conservation tillage increase enzyme activities. According to Bandick & Dick (1999), enzyme activities are generally higher in continuous grass fields than in cultivated fields. In cultivated systems, enzyme activity is higher where organic residues have been added as compared to treatments without organic amendments. Zakarauskaite et al. (2005) found higher urease activity in the soil where cereals were grown and higher saccharase and dehydrogenase activity whe","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130197334","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":"Rapid Establishment of the Alien Crab Rhithropanopeus Harrisii (Gould) in the Gulf of Riga/ Mudakrabi Rhithropanopeus Harrisii Kiire Naturaliseerumine Liivi Lahes","authors":"J. Kotta, H. Ojaveer","doi":"10.3176/ECO.2012.4.04","DOIUrl":"https://doi.org/10.3176/ECO.2012.4.04","url":null,"abstract":"INTRODUCTION Owing to its low salinity and short evolutionary history, the Baltic Sea virtually lacks native top predatory crabs. This contrasts to true oceanic waters where crabs constitute an essential element of the nearshore benthic ecosystems (e.g. Lee, 1998). To date, the only 'iconic' species in the Baltic Sea range is the Chinese mitten crab Eriocheir sinensis (H. Milne-Edwards). Despite occasional findings of this invasive species all over the coastal Baltic Sea, the reproduction of the mitten crab in the central, northern, and eastern Baltic regions is considered unlikely due to the low salinity, and the individuals caught are assumed to have actively migrated into the region over 1500 km distance (Ojaveer et al., 2007). However, the Baltic Sea also hosts the Harris mud crab Rhithropanopeus harrisii (Gould) (Fig. 1). This species has a native distribution from New Brunswick (Canada) to Veracruz (Mexico). In Europe the invasive species was first found in 1874 in the Netherlands, in the Baltic Sea area it was first observed in 1936 (Nikolaev, 1951). In contrast to E. sinensis, the mud crab is capable of reproducing in the diluted Baltic Sea and can form high-density populations (Maiju Lehtiniemi, pers. comm.); thus, it may exert strong pressure on the local benthic macrophyte and invertebrate communities. Despite its long invasion history, until very recently the distribution of R. harrisii was confined to Mecklenburg Bay, the Oder Estuary, the Gulf of Gdansk, and the Curonian Lagoon only (Jazdzewski & Konopacka, 1993; Bacevicius & Gasiunaite, 2008; Czerniejewski, 2009; Jazdzewski & Grabowski, 2011). Seemingly, R. harrisii has a large between population variability in Europe with more recent populations showing a tendency for increased genetic diversity (Projecto-Garcia et al., 2010). This suggests that R. harrisii is still in the process of expansion in Europe and its sudden northwards expansion seems to be a result of new introductions. In this study we report the sudden expansion of this alien invasive species over 500 km northwards and provide information on its distribution. [FIGURE 1 OMITTED] MATERIAL AND METHODS Crabs are not systematically monitored in the Estonian coastal sea. Nevertheless, since 1995 the Estonian National Monitoring Programme surveys benthic macrophytes and the associated invertebrates around the whole Estonian coastal range. In addition, the programme also surveys pelagic communities. The phytobenthos and zooplankton sampling and sample analysis follow the guidelines developed for the HELCOM COMBINE programme (HELCOM, 2012). Although not specifically targeted towards large and mobile invertebrates, the national monitoring programme is potentially capable of sighting the mud crab both in benthic and pelagic ecosystems. In addition, there is another local long-term activity that provides semiquantitative data on crabs. Specifically, this is done through the provision of artificial spawning substrata for the comme","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115097043","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":"Spatial and annual variability of environmental and phytoplankton indicators in Lake Võrtsjärv: implications for water quality monitoring","authors":"P. Nõges, L. Tuvikene","doi":"10.3176/ECO.2012.4.01","DOIUrl":"https://doi.org/10.3176/ECO.2012.4.01","url":null,"abstract":"Monitoring purposes determine the selection of variables, location of sampling sites, and sampling frequency. The selection should provide the best signal to noise ratio for the parameters of interest. For trend and surveillance monitoring, the deepest point of a lake, where different inputs to the lake are integrated, is frequently selected. However, the representativeness of a single site is often questioned, especially for large lakes. Based on data collected from 10 sampling points during 11 survey expeditions in August 2001-2011 to the large shallow Lake Vortsjarv, Estonia, we studied the spatial and annual variability of environmental and phytoplankton variables and analysed the representativeness of a permanent sampling station for the whole lake conditions. The two southernmost stations under the influence of the main tributary deviated clearly from the homogeneous group of the other eight stations, which we termed 'Vortsjarv Proper'. Among the stations of Vortsjarv Proper, the year-to-year variability dominated strongly over the spatial variability, the latter being almost negligible for most of the variables. Surface water temperature and water level explained approximately half of the total variability in parameters commonly used in ecological status assessment of lakes. This has serious implications for using these variables to detect human impacts in Vortsjarv. Our study showed that the deep sampling site, which was characterized by the lowest average variability of the parameters measured and was representative of more than 90% of the lake aquatory, possesses all necessary qualities required of a permanent surveillance monitoring station.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132535873","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 the ecological impact of an oil spill on shallow brackish-water benthic communities: a case study in the northeastern Baltic Sea","authors":"K. Herkül, J. Kotta","doi":"10.3176/ECO.2012.3.02","DOIUrl":"https://doi.org/10.3176/ECO.2012.3.02","url":null,"abstract":"The relationship between the abiotic environment and the structure of macrozoobenthos was studied in shallow bays of the southwestern Gulf of Finland, the Baltic Sea, that were impacted by a moderate oil spill in 2006. Seabed sediment characteristics, depth, and wave exposure best explained the structure of benthos. Statistical analyses did not show explicit effects of oil on benthos. The decrease in the abundance of Bathyporeia pilosa and Macoma balthica may be related to the oil, but it would be speculative to attribute this pattern solely to the spill without a proper before- after-control-impact (BACI) design with several control locations. Our study clearly showed that in the case of accidental environmental impacts like oil pollution it is impossible to apply a proper setup of the BACI design. This leads to difficulties in distinguishing between the effects of natural environmental factors and oil on the biota. The study also advocates for needs of alternative methodologies in order to effectively assess the impacts of accidental anthropogenic disturbances on benthic communities.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132391521","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":"Estonian Enchytraeidae 4. Sublittoral Enchytraeidae (Annelida, Oligochaeta) in the eastern Baltic Sea","authors":"T. Timm","doi":"10.3176/ECO.2012.3.01","DOIUrl":"https://doi.org/10.3176/ECO.2012.3.01","url":null,"abstract":"Only two enchytraeid species were found to be common and abundant in the sublittoral of the eastern Baltic Sea: a dwarfish form of Lumbricillus lineatus and Marionina naso n. sp., the latter probably belonging to the cool-water \"glacial relics\". Results are based on hundreds of samples from zoobenthos surveys made in the last century, covering the whole area. Descriptions of the two species are given. Several more species (Lumbricillus cf. arenarius, L. buelowi, L. cf. pumilio, Marionina southerni, M. spicula, and unidentified taxa) were found occasionally and in small numbers only.","PeriodicalId":262667,"journal":{"name":"Estonian Journal of Ecology","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129259695","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}