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Increase in abundance and species richness of flies (Diptera, Brachycera) in the Lake Engure Nature Park, Latvia: effects of climate warming?

Abstract

The article discusses changes in species richness and numbers of flies (Diptera, Brachycera) in the Lake Engure Nature Park (LENP) during 1995-2012. The study was performed within the framework of the National Long Term Ecological Research (LTER) network of Latvia. During the period of study, a statistically significant increase in positive temperature sums (> 4 °C) was observed at the local meteorological station (R2 = 0.489; P < 0.01). Insects were collected three times per season (June, July, and August) by entomological sweep net from twelve sample plots, which represented a variety of habitats of the LENP - dry xerophytic, mesophytic and humid hygrophytic ones. In total 411 species from 35 families were identified. Dry sample plots showed a statistically significant increase in species richness and/or numbers of flies during the period of study. Humid sample plots did not show any statistically significant trends except for two grassland plots where large herbivores were introduced in 2005 for grassland management purpose. Pooling the data from all sample plots, except those grazed by large herbivores, yielded a statistically significant trend of increase in species richness of flies (R2 = 0.647; P < 0.01). Among the main trophic groups zoophagous species showed the largest number of statistically significant positive trends mostly within the dry sample plots. For several sample plots significant positive correlations were recorded between species richness of zoophagous flies and annual sums of positive temperatures. It was hypothesised that climate warming may have an indirect effect via interaction with other environmental factors such as moisture regime, nitrogen pollution, and vegetation structure.

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Temporal species turnover and plant community changes across different habitats in the Lake Engure Nature Park, Latvia

References Adler, P. B. (2004). Neutral models fail to reproduce observed species-area and species-time relationships in Kansas grasslands. Ecology, 85 (5), 1265-1272. Adler, P. B., Lauenroth, W. K. (2003). The power of time: Spatiotemporal scaling of species diversity. Ecol. Lett., 6, 749-756. Anonymous (2007). Interpretation Manual of European Union Habitats. EUR 27. European Commission DG Environment. Auniòð, A. (Ed.) (2010). Eiropas Savienîbas aizsargâjamie biotopi Latvijâ. Noteikðanas

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Structure and dynamics of oligomesic dry pine forests in land zones of the Lake Engure catchment area

Abstract

Investigation of species composition, soil physical and chemical properties, as well as forest productivity of oligomesic dry pine forests (Vacciniosa and Myrtillosa forest types) was carried out in six dry land zones differing in age of the Lake Engure catchment area (sediment zones of the drained lakebed, Mia, Limnea, Litorina Sea, Baltic Ice Lake and glaciofluvial sediment zone in Northern Kursa Upland). Higher species diversity in the tree layer and a more typical podzolisation process was found in the older dry land zones (sediments of the Baltic Ice Lake, Northern Kursa Upland), while higher species diversity in the field layer (higher proportion of grasses and sword grasses), more intensive gleying process in soils, as well as considerably higher stand productivity was observed in the younger dry land zones (the drained lakebed, Mia, Limnea and Littorina Sea stages). Characteristic species of the Vaccinio-Piceetea class were dominant in the pine forests of older dry land zones, whereas species of the Pulsatillo-Pinetea class were typical in the sea coastal pine forests.

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Conceptual Model of the Long-Term Socio-Ecological Research Platform of Engure Ecoregion, Latvia

Abstract

The article discusses the results of the national project aimed at elaboration of a conceptual integrated model of the Engure LT(S)ER (Long-Term Socio-Ecological Research) platform of Latvia. The platform represents the drainage basin of costal Lake Engure (644 km2) together with the coastal marine zone of the Gulf of Rîga. The core zone of the ecoregion is the Lake Engure Nature Park (LENP), which is a Ramsar site. The conceptual model is a slightly modified version based on the DPSIR (Drivers-Pressures-States-Impacts-Responses) concept. The socioecological system was spatially demarcated and drivers were subdivided in two groups - external and local ones. The Engure ecoregion was subdivided into seven zones or sub-regions mostly demarcated by natural geological and geographical barriers. Each zone has a specific set of drivers and pressures as well as a specific ecosystem structure and elements of biodiversity. Analysis of the governing drivers and pressures was performed separately for each sub-region during three time periods: 19th century - beginning of 20th century, period of Soviet occupation (1940-1991), and period after restoration of independence of Latvia (1991 - up to now). Characteristics of the state of ecosystems and biodiversity are given. Responses of the socioeconomic component of the socio-ecological system are represented mainly by external factors to the ecoregion, including environmental legislation and funding necessary for research and ecological management. Two alternative scenarios of the development of the Engure ecoregion are discussed: (i) depopulation and land abandonment, and (ii) intensification of agriculture, small-scale industry and building construction. In both cases the present state of ecosystems and the structure of species diversity would be subjected to significant change. Sustainable development of the ecoregion can be provided only by implementation of certain environmental management measures accompanied by long-term socio-ecological research and ecological monitoring.

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Ecology and Diversity of Urban Pine Forest Soil Invertebrates in Rīga, Latvia / Augsnes Bezmugurkaulnieku Bioloģiskā Daudzveidība Urbānajos Priežu Mežos Rīgā, Latvijā

., Haimi, J., Pennanen, T., Fritze, H. (2002). Relationship between soil microarthropod species diversity and plant growth does not change when the system is disturbed. Oikos, 96, 137-149. Magura, T., Tóthmérész, B., Hornung, E., Horváth, R. (2008). Urbanisation and ground-dwelling invertebrates. In: Wagner, N. (Ed.). Urbanization: 21st Century Issues and Challenges. Nova Science Publishers Inc., New York, pp. 213-255. Manu, M., Honciuc, V. (2010). Rank correlations at the level of soil mites (Acari: Gamasida, Oribatida) from central parks

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The Influence of Plant Dominants on the Associated Species Abundance in Wet Tall-Herb Meadow Plant Communities

consequences. J. Veg. Sci ., 17 (2), 255–260. Hulbert, S. N. (1971).The non-concert of species diversity: A critique and alternative parameters. Ecology , 52 (4), 577–586. Houseman, G. R., Gross, K. L. (2011). Linking grassland plant diversity to species pools, sorting, and plant traits. J. Ecol ., 99 , 464–472. Ipatov, V. S., Kirikova, L. A., Major, I. A. (2007). Effects of Filipendula ulmaria ( Rosaceae ) on the neighbouring species in meadow societies [Ипатов, В. С., Кирикова, Л. А., Майор, И. А. Влияние Filipendula ulmaria ( Rosacea ) на

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