Abstract:We examined the genetic structure and diversity of eight populations of Eryngium maritimum L. (Sea Holly) along 150 km coastline of the Gulf of GdaÒsk in Poland. Allozyme electrophoresis revealed two polymorphic loci among the 31 we tested. The populations showed low levels of genetic diversity (P=6.25, A=1.062, Ht=0.026), with little genetic differentiation between populations (F ST =0.03), although it was statistically significant (p<0.001). The main directions of currents and wind indicate no significant limitations to the transport of seeds between populations in the region. Therefore, the grouping of populations that are mostly congruent with their geographic locations (except HP1) might result from the low efficacy of gene flow by seeds. The significant genetic differentiation of HP1, even from close neighboring populations, might have arisen from the founder effect and barriers to the gene flow caused by anthropogenic factors such as forestation and the construction of breakwaters.

Żółkoś K., Meissner W.: Influence of cormorant Phalacrocorax carbo colony on biometrical parameters of three-nerved sandwort Moehringia trinervia (Caryophyllaceae) leaves and seeds. Ekológia

This work presents the results of studies aimed at assessing the median and maximum distances covered by wild mallards (Anas platyrhynchos; n = 38), hypothetically infected with the high pathogenicity avian influenza virus (HPAIV) during spring migrations, using GPS-GSM tracking and published data on the susceptibility to HPAIV infection and duration of shedding. The model was based on the assumptions that the birds shed virus in the absence of clinical signs during infectious periods (IP) that were assumed to last 1 day (IP1), 4 days (IP4), and 8 days (IP8) and that each day of migration is a hypothetical day of the onset of IP. Using the haversine formula over a sliding timeframe corresponding to each IP, distances were estimated for each duck that undertook migration and then the maximum distance (Dmax) was selected. Ten mallards undertook spring migrations but, due to the loss of signal in the GPS-GSM devices, only three ducks were observed during autumn migrations. The following ranges of Dmax values were calculated for spring migrations: 124-382 km for IP1 (median 210 km), 208-632 km for IP4 (median 342 km), and 213-687 km for IP8 (median 370 km). The present study provides information that can be used as a data source to perform risk assessment related to the contribution of wild mallards in the dispersal of HPAIV over considerable distances.

No abstract

Establishing plantations of quick growing introduced trees, combined with effect of a bird colony, affect habitat conditions. This causes alterations in spatial structure of a phytocenosis, its species composition and size of plants in herb layer. In the studied Khasi pine (PinuskesiyaRoyle ex Gordon) stand in central Madagascar the shrub layer was found only under egrets' nests, while it did not occur outside the colony. We observed four times higher number of species, and much greater coverage of shrub and herb layers in the colony than outside, which reflects the increased soil trophy in the colony. One of the common species of herb layer was Commelinaafricana. Leaf blades of its exemplars growing under the egret nests were on average larger, which provided greater surface of the assimilative apparatus, than of those growing outside the colony. All differences between the in the studied tree stands seem to reflect soil enrichment in nutrients caused by the excretions from egrets. Such changes in phytocoenoses caused by effect of bird colonies have been studied so far only in cold and temperate climates. Our results confirm a similar effect of birds' breeding on a plant community in a tropical climate.