A list of alien plant species recorded from Svalbard in the summer of 1988 is presented. Two localities, the Russian settlements of Barentsburg and Pyramiden on the Isfjorden, Spitsbergen, were studied. Prior to this study, almost 60 alien species were recorded from Svalbard by other investigators. During the research reported here, 44 taxa were found, 14 of which are new records for the Svalbard archipelago. Six species are considered to be possibly naturalized; however, it is difficult to assess their naturalization status because of the severity of the climate in the study area. A complete list of species is presented, with information on height and phenological stage of particular specimens. Most of the alien plants recorded at the two settlements belong to the family Brassicaceae.
This review compares the current state of ichthyofauna in the largest rivers of the northern coast of the Black Sea (Don, Kuban, Dnieper and Dniester rivers) with data published by B e r g (1948–1949). Changes in species composition are characterized by the disappearance or decline in anadromous and semi-anadromous fishes. The total number of native species that are extinct, protected, in declined or become rare has reached from 19 % in the Kuban to 36 % in the Dnieper River basins. Appreciable changes have occurred in the ratios between rheophilous and limnophilous fishes (the latter becoming predominant in many parts of the rivers). Euryhaline and even marine species have invaded most of river basins. And the number of introduced or established alien species varies from 9.7 % in the Dnieper to 16.8 % in the Kuban River basins. These changes, which have yielded quite altered ichthyofauna, must be taken into consideration in conservation endeavours.