Variations in breeding success and daily nest survival of Whiskered Tern (<Emphasis Type="Italic">Chlidonias hybrida</Emphasis>) at two Iranian colonies

Variations in breeding success of the Whiskered Terns (Chlidonias hybrida) were studied in two wetlands; Anzali (2005 and 2008) and Zarivar (2007–2008) in north and west Iran. Nesting success was modeled and compared using information-theoretic approach implemented in program Mark in order to assess effects of colony locations, years and nest initiation dates on the probability of daily nest survival. Clutch size did not vary between colonies and years. Breeding success varied between colonies (Zarivar > Anzali), and years only in Anzali (2005 > 2008). Overall daily nest survival was 0.977. (95% LCI 0.973, UCI 0.981), equivalent to a Mayfield nest survival of 0.317. (95% LCI 0.255, UCI 0.387). Egg-laying periods and colony site were important covariates affecting the daily survival rates (Σω _i = 0.86 and Σω _i = 0.83, respectively), while, the support for the effect of year was less (Σω _i = 0.41). We concluded that Lake Zarivar provides a more favorable nesting location for Whiskered Terns probably because of little changes in rainfall and water depth during the breeding seasons which influence breeding performance.     

Exoautometabolic regulation of transgenes in microorganisms

Data on the existence of a specific system regulating the growth, size, and structure of enterobacterial populations are first summarized in terms of the chemical ecology concept formulated by S.S. Shvarts. The role of this system in transgene functioning is described using the example of the lux operon integrated into Escherichia coli. A relatively simple test for estimating such interactions is proposed.Translated from Ekologiya, No. 2, 2005, pp. 91–96.Original Russian Text Copyright © 2005 by Pshenichnov, Maslennikova, Nikitina.     

Effects of the <Emphasis Type="Italic">Astacus astacus</Emphasis> L. Population on Biomass of Macrophytes in a Fresh Water Body

In experiments performed in aquariums, the daily consumption of Chara vulgaris alga by crayfish (Astacus astacus L.) has been determined. These quantitative data have been used to make a prognosis of the effect of the A. astacus population on the biomass of macrophytes in Lake Berezovo (Pskov oblast). The density of the crayfish population and the biomass of higher aquatic vegetation in the lake have been determined in field studies. Extrapolation of the results of laboratory experiments to a natural water body has shown that crayfish are capable of controlling no less than 40% of submersed macrophytes in the area used by their population.__________Translated from Ekologiya, No. 4, 2005, pp. 300–305.Original Russian Text Copyright © 2005 by Kholodkevich, Shumilova, Fedotov, Zhuravlev.     

The role of interactions between individual animals in the response to heat stress in the freshwater crustacean <Emphasis Type="Italic">Daphnia magna</Emphasis>

The thermal resistance of Daphnia magna Straus is a trait depending on the interaction between individuals. The group effect is expressed in D. magna as both a decrease in thermal resistance and a marked individual differentiation with respect to thermal resistance. Two types of interactions between individual D. magna have been found: (1) the release of an unidentified factor decreasing thermal resistance (without noticeably changing the phenotypic variability of this trait) into the medium and (2) a decrease in the thermal resistance of individuals poorly adapted to heat stress, with the thermal resistance of well-adapted individuals (determined by the dependence of thermal resistance on interactions between individuals) remaining the same or even slightly increasing.Translated from Ekologiya, No. 2, 2005, pp. 126–131.Original Russian Text Copyright © 2005 by Kalinnikova, Krasnoperova, T. Gainutdinov, Sadykova, M. Gainutdinov.     

Ecological and genetic characteristics of the distribution of <Emphasis Type="Italic">Bradybaena fruticum</Emphasis> Mull. (mollusca,gastropoda, pulmonata) in a forest-steppe landscape

The distribution pattern of the gastropod Bradybaena fruticum has been studied in a forest-steppe landscape. Analysis of the frequencies of polymorphic biochemical and conchological characters has yielded preliminary results on the characteristics of the species population structure whose formation was determined by a set of natural and anthropogenic factors.Translated from Ekologiya, No. 1, 2005, pp. 39–47.Original Russian Text Copyright © 2005 by Snegin.     

Effect of site conditions on the formation of wood anatomical structure in the cajander larch (Larix cajanderi Mayr) in the Amur region

Studies on the Cajander larch (Larix cajanderi) in the Amur region have been performed to evaluate the effect of growth conditions on the development of wood anatomical structure during ontogeny, including the course and rate of definitive (mature) wood formation. Adaptive changes in wood anatomy have been revealed in trees growing in waterlogged areas underlain by permafrost.     

Ecology of Nuclear Polyhedrosis Virus in Western Siberian Populations of the Gypsy Moth (<Emphasis Type="Italic">Lymantria dispar</Emphasis> L.)

The impact of the nuclear polyhedrosis virus on the population dynamics of the gypsy moth Lymantria dispar L. has been studied. The results have shown that polyhedrosis morbidity in the western Siberian population of the insect is relatively low, compared to that reported for North American and European populations. A possible cause of this situation is found in the high migration activity of moths in the Asian L. dispar populations, which allows the virus load on the biotope to remain relatively stable and insufficient for the initiation of mass viral diseases during population outbreaks.__________Translated from Ekologiya, No. 3, 2005, pp. 222–226.Original Russian Text Copyright © 2005 by Ilinykh.     

Irregularity in frequency of mast seed years in <Emphasis Type="Italic">Quercus floribunda</Emphasis> a late successional species of Central Himalaya

The mid altitudinal oak, Quercus floribunda forms predominantly evergreen forest in Central Himalaya between 2000–2400 m. It is late successional, mature phase species that has limited regeneration on disturbance prone sites. This oak produces mast seed crops at an interval of 2–3 years. During masting in Q. floribunda the seed fall and germination is upto ten times greater than in normal years, emphasizing the importance of mast year crop in forest maintenance. However, no mast year in this species since the last nine years (1997–2005) is a matter of serious concern. The rise in the summer and winter temperature over a period of 15 years appear to have affected the frequency of masting in this oak. The importance of masting can be adjudged from the fact that 97% of the surviving seedlings m⁻² are of the mast year crop.     

Relationships between developmental instability in morphological characters and fitness of <Emphasis Type="Italic">Aphis fabae</Emphasis> population reared on two host plants

Fluctuating asymmetry (FA) and the coefficient of within-environment variation (CV _e) are often used as measures of developmental instability and indicators of developmental deviations. Aphis fabae genotypes generally manifest higher developmental instability on novel host plants, but there is genotypic variability in this respect. Some genotypes have manifested lower developmental instability on nasturtium, where their fitness is higher. At the population level, aphids reared on nasturtium have shown higher developmental instability and lower fitness. When large samples are analyzed and the nonsignificant pattern of correlations is taken into account, the results of the study do not support the hypothesis that developmental instability is always a reliable indicator of fitness. Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 131–136. The text was submitted by the authors in English.     

Evaluation of DNA damage in the root cells of Allium cepa seeds growing in soil of high background radiation areas of Ramsar – Iran

Plants are unique in their ability to serve as in situ monitors for environmental genotoxins. We have used the alkaline comet assay for detecting induced DNA damage in Allium cepa to estimate the impact of high levels of natural radiation in the soils of inhabited zones of Ramsar. The average specific activity of natural radionuclides measured in the soil samples for ²²⁶Ra was 12,766 Bq kg⁻¹ whereas in the control soils was in the range of 34–60 Bq kg⁻¹. A positive strong significant correlation of the DNA damage in nuclei of the root cells of A. cepa seeds germinated in the soil of high background radiation areas with ²²⁶Ra specific activity of the soil samples was observed. The results showed high genotoxicity of radioactively contaminated soils. Also the linear increase in the DNA damage indicates that activation of repair enzymes is not triggered by exposure to radiation in HBRA.     

Site Tenacity in the Willow Ptarmigan (<Emphasis Type="Italic">Lagopus lagopus</Emphasis> L.) in the Northern Yamal Peninsula

The return of willow ptarmigans to the sites in which they nested the previous year has been studied using color banding. No factors influencing the return index have been revealed, except for its dependence in males on the time when spring begins in a given year. In northernYamal, in contrast to the temperate zone, some surviving birds fail to return to their former nesting sites. Polymorphism of individuals with respect to territorial behavioral strategy is proposed for L. lagopus populations at the northern boundary of the species range.__________Translated from Ekologiya, No. 3, 2005, pp. 215–221.Original Russian Text Copyright © 2005 by Tarasov.     

Intrapopulation Differentiation by the Rates of Rosette Growth and Individual Plant Development in Narrow-Leaved Hawk’s Beard (<Emphasis Type="Italic">Crepis tectorum</Emphasis> L.): Aftereffects of Long-Term Stress

Aftereffects of exposure to long-term chemical pollution with fluorine and sulfur compounds on intrapopulation differentiation of the rates of growth and development has been studied on Crepis tectorum L. progenies obtained from seeds collected in a pollution gradient and grown in a greenhouse under uniform ecological conditions. The results have shown that long-term stress (exposure to toxic gaseous pollutants) leads to significant changes in the intrapopulation structure, which are manifested in an increase in the proportion of plants with a low rate of development, a low relative rate of the linear growth of metameres (leaves), but a higher relative rate of their formation.__________Translated from Ekologiya, No. 4, 2005, pp. 243–251.Original Russian Text Copyright © 2005 by Trubina.     

The narrow-skulled vole (<Emphasis Type="Italic">Microtus gregalis</Emphasis> Pall.) in the dynamics of zonal rodent communities of northern Eurasia

On the basis of abundant fossil and subfossil bone remains, the ecological and faunal role of the narrow-skulled vole in zonal rodent communities of northern Eurasia is analyzed over the period from the Late Pleistocene to the present time. Special attention is given to the correlated dynamics of relative abundance of Microtus gregalis and other rodent species in the course of transition from one zonal type to another and to specific features of this correlation in the southern, middle, and northern parts of the species range. It is shown that distinctive dimensional and morphotypic features of the two currently existing subspecies, Microtus gregalis major Ogn. and M. g. gregalis Pall., are the product of concordant development of the species and environmental conditions in the past 3000–4000 years (transition from the Holocene optimum to the present-day climate and state of the natural environment). Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 117–123. The article was translated by the authors.     

Competition between the Rotifers Brachionus patulusand Euchlanis dilatata:Effect of Algal Food Level and Relative Initial Densities of Competing Species

We tested the effect of different algal (Chlorella vulgaris) levels and inoculation densities on the outcome of competition between the rotifers Euchlanis dilatata and Brachionus patulus. The experiment was performed in 36 transparent jars, each with 20 ml of a test medium. We used three Chlorella levels: 0.75 × 10⁶, 1.5 × 10⁶, and 3.0 × 10⁶ cells/ml. For each algal level, we used five different ratios of initial inoculation density. The population growth experiments were terminated after 19 days. Regardless of inoculation densities, an increase in food level resulted in an increased population abundance of both rotifer species. Regardless of food concentration,E. dilatatawas able to outcompete B. patulus at all inoculation densities when grown together. However, when Chlorella was offered in low concentration and there was a higher ratio of Brachionus to Euchlanis at the onset of the experiment, both rotifer species coexisted in more or less equal densities until the end of the experiments. When the food level was enhanced, E. dilatata totally eliminated B. patulus. The rate of population growth ranged from 0.002 to 0.578 for B. patulus and from 0.006 to 0.447 for E. dilatata. The results are discussed with respect to the factors influencing the outcome of competition between species.     

Isotope tracing of submarine groundwater discharge offshore Ubatuba, Brazil: results of the IAEA–UNESCO SGD project

Results of groundwater and seawater analyses for radioactive (³H, ²²²Rn, ²²³Ra, ²²⁴Ra, ²²⁶Ra, and ²²⁸Ra) and stable (D and ¹⁸O) isotopes are presented together with in situ spatial mapping and time series ²²²Rn measurements in seawater, direct seepage measurements using manual and automated seepage meters, pore water investigations using different tracers and piezometric techniques, and geoelectric surveys probing the coast. This study represents first time that such a new complex arsenal of radioactive and non-radioactive tracer techniques and geophysical methods have been used for simultaneous submarine groundwater discharge (SGD) investigations. Large fluctuations of SGD fluxes were observed at sites situated only a few meters apart (from 0 cm d⁻¹ to 360 cm d⁻¹; the unit represents cm³/cm²/day), as well as during a few hours (from 0 cm d⁻¹ to 110 cm d⁻¹), strongly depending on the tidal fluctuations. The average SGD flux estimated from continuous ²²²Rn measurements is 17 ± 10 cm d⁻¹. Integrated coastal SGD flux estimated for the Ubatuba coast using radium isotopes is about 7 × 10³ m³ d⁻¹ per km of the coast. The isotopic composition (δD and δ¹⁸O) of submarine waters was characterised by significant variability and heavy isotope enrichment, indicating that the contribution of groundwater in submarine waters varied from a small percentage to 20%. However, this contribution with increasing offshore distance became negligible. Automated seepage meters and time series measurements of ²²²Rn activity concentration showed a negative correlation between the SGD rates and tidal stage. This is likely caused by sea level changes as tidal effects induce variations of hydraulic gradients. The geoelectric probing and piezometric measurements contributed to better understanding of the spatial distribution of different water masses present along the coast. The radium isotope data showed scattered distributions with offshore distance, which imply that seawater in a complex coast with many small bays and islands was influenced by local currents and groundwater/seawater mixing. This has also been confirmed by a relatively short residence time of 1–2 weeks for water within 25 km offshore, as obtained by short-lived radium isotopes. The irregular distribution of SGD seen at Ubatuba is a characteristic of fractured rock aquifers, fed by coastal groundwater and recirculated seawater with small admixtures of groundwater, which is of potential environmental concern and has implications on the management of freshwater resources in the region.     

Effect of phytoremediation in technogenic landscapes of mining areas on the functioning of actinomycete communities

It has been shown that conditions formed in technozems of tailing dumps covered with a layer of chernozem are optimal for the development of soil microflora, including actinomycetes, as follows from their high abundance. The use of Leymus sabulosus (Bieb.) Tzvel in biological remediation of technozems formed in tailing dumps ensures an increase not only in the abundance of microorganisms in edaphotopes but also in their ecological diversity, compared to technozems planted with Rhus hirta (L.) Sudw, as confirmed by 1.2- and 1.9-fold increase in the Margalef and Berger–Parker diversity indices. Therefore, applying a layer of chernozem on technozems of tailing dumps provides for more efficient remediation of technogenic soils.     

Dynamics of Yielding Capacity of Small Cranberry in Southern Karelia

The dynamics of yielding capacity of small cranberry (Oxycoccus palustris Pers.) were studied in three permanent sampling plots in a natural bog in southern Karelia for 28 years (1975–2002). The yield of berries varied from year to year from 1 to 179 g/m² depending on phytocenotic and, to a greater extent, climatic factors. The proportion between the number of ripe berries and the number of flowers varied from 10 to 66%. No distinct periodicity in the abundance of fruiting was revealed.__________Translated from Ekologiya, No. 4, 2005, pp. 264–268.Original Russian Text Copyright © 2005 by Yudina, Maksimova.     

Bioindication-based Estimation of Technogenic Impact on <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L. Populations in the Vicinity of a Radioactive Waste Storage Facility

The spectrum and frequency of cytogenetic aberrations in the reproductive (seeds) and vegetative (foliage) organs of Scotch pine (Pinus sylvestris L.) have been studied in the vicinity of the LSK Radon facility for radioactive waste storage and processing and in a 30-km zone around the Chernobyl Nuclear Power Plant. The results indicate that the pine populations of these regions are exposed to mutagenic factors. In contrast to the 30-km Chernobyl zone, the increased environmental mutagenicity in the vicinity of LSK Radon and in the center of the city of Sosnovyi Bor is mainly accounted for by chemical factors. The results of additional acute γ-irradiation have shown an increased radiation resistance of Scotch pine seeds from the LSK Radon and Sosnovyi Bor populations. Regression analysis demonstrated a significant increase in the cytogenetic aberration rate in plants from the experimental plots throughout the study period (1997–2002).__________Translated from Ekologiya, No. 4, 2005, pp. 275–285.Original Russian Text Copyright © 2005 by Geras’kin, Vasil’ev, Dikarev, Udalova, Evseeva, Dikareva, Zimin.     

Formation of aggregated settlements as an expression of synanthropization of the long-eared owl (<Emphasis Type="Italic">Asio otus</Emphasis> L.)

The structure of the long-eared owl (Asio otus L.) settlements in anthropogenic landscapes has been studied in the Zhuravlinaya Rodina protected territory in the northern Moscow region in 2001–2005. The possible factors that cause the formation of such settlements have been analyzed. The differences in the breeding success between owls nesting near and away from human settlements have been estimated. Aggregated nesting of owls is assumed to be mainly related to a lower predator pressure in the vicinity of human dwellings in the incubation period. Aggregated nesting is regarded as an expression of synanthropization of the species.