Russian Journal of Biological Invasions

2015, issue № 3

CONTENTS

Invasive successions as the indicator of desertification of dry steppe by way of example of Central Mongolia - Bazha S.N., Gunin P.D., Danzhalova E.V., Drobyshev Yu.I., Kazantseva T.I., Ariunbold E., Myagmarsuren D., Khadbaatar S., Tserenkhand G. - The studies of the steppe ecosystems in Central Mongolia carried out by us showed that over recent decades a simplification of steppe communities took place. It occurred by reduction of species diversity and abundance of indigenous dominants - tussock grasses, that was a result of sharp rise in pasture loads and a long dry period.

We have identified two types of introduction of invasive species from different landscapes: a) extra- and intrazonal and b) zonal. The first type of succession is characterized by focal distribution of Ephedra sinica from ecosystems of low mountains to the surrounding mountain plains. The second type of succession in dry steppes is associated with the expansion of Allium polyrrhizum, which distribution has largely frontal character and is caused by the weakening of the competitiveness of indigenous species of grass communities because of their significant digression. A further factor in ensuring the conditions for invasion is the aeolian alkalization of the upper horizons of zonal chestnut soils.

Ecological and biological features of these two species, widespread in the desert-steppe and desert landscapes and penetrating into the steppe ecosystems, allow us to speak about biological desertification. The wide area of Ephedra sinica and Allium polyrrhizum indicates a progressive character of the studied types of succession, and as a result of which the borders of these areas have reached the southern periphery of the Baikal Lake basin at present.

The processes described in the paper lead to a decrease in fodder value of pastures and jeopardize the maintenance of cattle-breeding in Central Mongolia.

bout flowering biology of alien species. 3. Caragana arborescens Lam. and C. laeta Kom. - Kuklina A.G., Vinogradova Yu.K., Tkacheva E.V. - Some data on flowering biology of potentially aggressive alien species – Caragana arborescens are presented. Micromorphological characters of flowers at different stages of development for typical plants and two cultivars (C. arborescens f. pendula and C. arborescens f. lorbergii), and also for the Central Asian C. laeta are described. The pollen fertility is defined. A number of characters in which C. arborescens has a competitive superiority over closely related taxa is revealed. Arguments for C. arborescens f. lorbergii allocation as a particular taxon are adduced.

Sharpbelly Hemiculter leucisculus (Basilewsky, 1855) (Cypriniformes, Cyprinidae) is a successful invasive species in freshwaters of Azerbaijan - Mustafayev N.J., Ibrahimov Sh.R., Levin B.A. - The invasive species, sharpbelly Hemiculter leucisculus, was found in Caspian Sea drainage, Azerbaijan, which species status was confirmed by analysis of two loci of mtDNA, COI and cytochrome b. Data on distribution, morphology and biology of sharpbelly in freshwaters of Azerbaijan are given in the paper. Nowadays, sharpbelly Hemiculter leucisculus is a common, naturalized species widely distributed throughout Azerbaijan. Occasional introduction during program of introduction of valuable species to Azerbaijan or penetration from waterbodies of adjacent countries, where this species was detected previously as an invasive one, are discussed as probable ways of colonization of Transcaucasian freshwaters.

Heat-loving and eastern pacific migrants in ichthyofauna of the Pacific waters of the Northern Kuril islands and Kamchatka in XX–XXI centuries - Tokranov A.M., Orlov A.M. - Data on the species composition and occurrence of the heat-loving and Eastern Pacific representatives of ichthyofauna in the Pacific waters of the Northern Kuril Islands and Eastern Kamchatka in XX–XXI centuries are provided. Thirty three species of heat loving and twelve species of Eastern Pacific fish and lampreys from 35 families have been registered during this period in Pacific waters near the Kuril Islands and Kamchatka. Annual and seasonal dynamics of appearance of some fish species in investigated region in 1992–2002 are analyzed.

Feeding peculiarities in Atlantic salmon fry (Salmo salar L.) infected with invasive parasite Gyrodactylus salaris in River Keret - Tyrkin I.A., Shustov Yu.A., Rasputina E.N., Legun A.G. - Young Atlantic salmon inhabiting the Keret River (the White Sea basin) and infected with invasive monogeneans – Gyrodactylus salaris – shows very low feeding intensity because of physical weakness in summer. Only a few individuals of benthic invertebrates – caddis fly larvae, nymphs, stoneflies and mayflies, and molluscs are found in the stomachs of infected patients and fingerling salmon. Compared with healthy fish from the White Sea salmon rivers Ponoy and Kachkovka (Kola Peninsula), the overall index of stomach filling in the young salmon of the Keret River is reduced by an average of 5–7 times. Approximately one third of invasive fingerlings have empty stomachs that almost is never observed in the nutrition of wild juvenile Atlantic salmon in the summer feeding period in the rivers of Karelia and Kola Peninsula.

Modern composition of alien fish species in Kuybyshev reservoir and possible introduction of new representatives into its ecosystem - Shakirova F.M., Severov Yu.A., Latypova V.Z. - The data on alien fish species composition of the Kuybyshev reservoir, the period of their detection, and the vectors of their introduction into the reservoir are provided. The possibilities of penetration of new representatives into the reservoir ecosystem are analyzed.