Contribution to studies on white-tailed eagle (Haliaeetus albicilla Linnaeus, 1758) in Western Serbia and the Republic of Srpska

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Freshwater jellyfish Craspedacusta sowerbyi Lankester, 1880 (Hydrozoa, Olindiidae): 50 years' observations in Serbia

Detailed and relevant limnological investigations of Serbian waters were initiated in 1958 and have continued to the present. During the period 1971-2008 we monitored biological elements as a part of working studies/projects, including the distribution of the freshwater jellyfish Craspedacusta sowerbyi Lankester, 1880. We observed over 500 sampling sites in running and standing waters. Specimens of this hydro-medusa were found in five of them. Throughout the period of investigation, only the medusae stages were observed. Our purpose in this paper was to provide data of the records and distribution of this limnomedusa during the period 1958-2008 in inland waters of Serbia. These observations should contribute to knowledge on the limnofauna not only of the Balkan Peninsula but Europe as a whole.Opsežna i značajna limnološka istraživanja voda u Srbiji otpočela su 1958. godine i nastavljena do danas. Tokom celog istraživačkog perioda nađena je slatkovodna meduza Craspedacusta sowerbyi Lankester, 1880 na pet lokaliteta (bara na Velikoj Moravi kod Ćuprije, Savsko jezero kod Beograda, jezero Velika Peščara kod Zrenjanina, jezero Miloševo kod Jagodine i jezero Šumarice kod Kragujevca). Predstavljeni rezultati su doprinos dosadašnjih saznanja o nalazima i distribuciji ove vrste u Srbiji, kao i poznavanju limnofaune Balkanskog poluostrva i Evrope.Projekat ministarstva br. 14302

Contribution to studies on white-tailed eagle (Haliaeetus albicilla Linnaeus, 1758) in Western Serbia and the Republic of Srpska

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Photosynthetic activity of Fagus sylvatica L. and Quercus petraea (Matt) Liebl. in a mixed stand at Maljen mountain

Estimation of the photosynthetic performance of co-existing tree species with pronounced differences in ecophysiological context (Aranda et al. 1996 Leuschner et al. 2001) could provide insight into their vitality and competitive abilities at a particular site. Gas exchange, composition of photosynthetic pigments, and the water status of beech (Fagus sylvatica L) and sessile oak (Quercus petraea (Matt) Liebl) were studied in the present work. The investigation was performed on Mt. Maljen (Western Serbia, near the town of Mionica) at an altitude of 950 m, in an ecotope within the confines of the mountain's beech forest belt. Codominant samplings [three of each species, 30-years old (n=6), 10-12 m high] were selected for the measurements, which were conducted on fully developed leaves from the outermost branches and from the innermost canopy. Photosynthetic measurements were performed using an LI-6200 closed photosynthesis system (LI-Cor. Inc, Lincoln, NE, USA), while irradiance was detected with a selenium cell mounted on the leaf chamber. Parameters of gas exchange are expressed on the basis of leaf area, using the AREAMETER software (Karadžić et al. 1999). Chlorophyll content was spectrophotometrically determined based on light absorption of the solution obtained after extraction with dMSO (Hiscox and Israelstam, 1979). The midday water saturation deficit was determined according to Turner (1981). For data analysis, we used the Statistic for Windows program package. The ANOVA one-way breakdown was applied to compare differences within (leaves inside vs. leaves outside the surface of the tree canopy) and between species for all investigated parameters at the 0.05 level of significance.nul

Photosynthetic activity of Fagus sylvatica L. and Quercus petraea (Matt) Liebl. in a mixed stand at Maljen mountain

Estimation of the photosynthetic performance of co-existing tree species with pronounced differences in ecophysiological context (Aranda et al. 1996 Leuschner et al. 2001) could provide insight into their vitality and competitive abilities at a particular site. Gas exchange, composition of photosynthetic pigments, and the water status of beech (Fagus sylvatica L) and sessile oak (Quercus petraea (Matt) Liebl) were studied in the present work. The investigation was performed on Mt. Maljen (Western Serbia, near the town of Mionica) at an altitude of 950 m, in an ecotope within the confines of the mountain's beech forest belt. Codominant samplings [three of each species, 30-years old (n=6), 10-12 m high] were selected for the measurements, which were conducted on fully developed leaves from the outermost branches and from the innermost canopy. Photosynthetic measurements were performed using an LI-6200 closed photosynthesis system (LI-Cor. Inc, Lincoln, NE, USA), while irradiance was detected with a selenium cell mounted on the leaf chamber. Parameters of gas exchange are expressed on the basis of leaf area, using the AREAMETER software (Karadžić et al. 1999). Chlorophyll content was spectrophotometrically determined based on light absorption of the solution obtained after extraction with dMSO (Hiscox and Israelstam, 1979). The midday water saturation deficit was determined according to Turner (1981). For data analysis, we used the Statistic for Windows program package. The ANOVA one-way breakdown was applied to compare differences within (leaves inside vs. leaves outside the surface of the tree canopy) and between species for all investigated parameters at the 0.05 level of significance.nul

Research on long-term colonization of goosander (Mergus merganser Linneaus, 1758) with reference to habitat availability

This article presents data on long-term colonization of goosander in Western Serbia and Eastern Republic of Srpska (on five oligotrophic reservoirs formed by the Drina River) based on continuous counting since the first observation of nesting in 1987. The total number of breeding pairs and their distribution in neighboring habitats continuously increased from year to year, suggesting that expansion of the population is still below the limit of the habitat. The decrease in population which occurred in certain years was due to environmental or anthropogenic influence

Photosynthetic activity of Fagus sylvatica L. and Quercus petraea (Matt) Liebl. in a mixed stand at Maljen mountain

Estimation of the photosynthetic performance of co-existing tree species with pronounced differences in ecophysiological context (Aranda et al. 1996 Leuschner et al. 2001) could provide insight into their vitality and competitive abilities at a particular site. Gas exchange, composition of photosynthetic pigments, and the water status of beech (Fagus sylvatica L) and sessile oak (Quercus petraea (Matt) Liebl) were studied in the present work. The investigation was performed on Mt. Maljen (Western Serbia, near the town of Mionica) at an altitude of 950 m, in an ecotope within the confines of the mountain's beech forest belt. Codominant samplings [three of each species, 30-years old (n=6), 10-12 m high] were selected for the measurements, which were conducted on fully developed leaves from the out­ermost branches and from the innermost canopy. Photosynthetic measurements were performed using an LI-6200 closed photo­synthesis system (LI-Cor. Inc, Lincoln, NE, USA), while irradiance was detected with a selenium cell mounted on the leaf chamber. Parameters of gas exchange are expressed on the basis of leaf area, using the AREAMETER software (Karadžić et al. 1999). Chlorophyll content was spectrophotometrically determined based on light absorption of the solution obtained after extraction with dMSO (Hiscox and Israelstam, 1979). The midday water saturation deficit was determined according to Turner (1981). For data analysis, we used the Statistic for Windows program package. The ANOVA one-way break­down was applied to compare differences within (leaves inside vs. leaves outside the surface of the tree canopy) and between species for all investigated parameters at the 0.05 level of significance

RESEARCH ON LONG–TERM COLONIZATION OF GOOSANDER (MERGUS MERGANSER LINNEAUS, 1758) WITH REFERENCE TO HABITAT AVAILABILITY

Abstract — This article presents data on long-term colonization of goosander in Western Serbia and Eastern Republic of Srpska (on five oligotrophic reservoirs formed by the Drina River) based on continuous counting since the first observation of nesting in 1987. The total number of breeding pairs and their distribution in neighboring habitats continuously increased from year to year, suggesting that expansion of the population is still below the limit of the habitat. The decrease in population which occurred in certain years was due to environmental or anthropogenic influence

Axenically Culturing the Bryophytes: Establishment and Propagation of the Pleurocarpous Moss Thamnobryum Alopecurum Nieuwland Ex Gangulee (Bryophyta, Neckeraceae) in In Vitro Conditions

The study gives the first report of In vitro culture of the moss Thamnobryum alopecurum and the insight into the problems of axenicaly culturing this bryophyte and the conditions for establishment and propagation. This moss is a counterpart of many rare and endangered mosses from the same genus and date presented should be taken into account of conservation and propagation of its counterparts as well. Problems of surface sterilization are elaborated regarding sporophyte vs. gametophyte. The influence of nutrient, light length and temperature on different developmental stages is discussed. The best conditions for micro-propagation from shoots are slightly lower temperature (18-20 degrees C), on BCD medium irrelevant of day length.Minsitry of Science of Republic of Serbia [173024, 173030

In Vitro Development of the Rare and Endangered Moss Molendoa hornschuchiana (Hook.) Lindb. ex Limpr. (Pottiaceae, Bryophyta)

The high mountain pottioid moss Molendoa hornschuchiana (Hook) Lindb. ex Limpr. is a very rare and critically endangered bryophyte species in Europe in need for ex situ conservation. A 25-year-old herbarium sample was used to revive and propagate this species for further reintroduction and introduction to potential natural habitats. The reviving of "dead" herbarium specimen was achieved by disposing of axenical organisms as well as adjusting condition for developing secondary protonema, bud inductions, and optimization of gametophyte propagation in vitro condition. The influence of exogenously added growth regulators on the morphogenesis of this species was studied. The plants were cultured in the two basic types of media, viz., BCD and half-strength Murashige and Skoog (MS) supplemented with different concentrations (0.01-0.3 mu M) of indole-3-butyric acid (IBA) and N-6-benzyladenine (BA) under a 16-h photoperiod. The influence of growth regulators on gametophores multiplication in vitro as well as on protonemal diameter was recorded. Well-developed gametophores were obtained on BCD medium, whereas on half-strength MS medium, secondary protonema was produced, both on hormone-free and supplemented substrate exclusively. Based on multiplication index in vitro, maximum development of gametophores was realized on BCD medium supplemented with 0.3 mu M IBA and 0.1 mu M BA. However, the widest diameter of secondary protonema was obtained on BCD medium enriched with low concentration of both BA (0.01 and 0.03 mu M) and constant concentration of IBA (0.03 mu M). Chemical names used: indole-3-butyric acid (IBA), N-6-benzyladenine (BA), Murashige and Skoog medium (MS).Ministry of Education and Science of the Republic of Serbia [173024, 173030