Vol 47, No 4 (2016)

The needles of juniper growing in spruce and birch forests of the Khibiny Mountains have been analyzed to evaluate the pattern of changes in their chemical composition (ADF, lignin, cellulose, lignin/cellulose, lipids, phenolic compounds, proanthocyanidins, flavonoids, N, C, and also Ca, Mg, K, Mn, Zn, P, S, Al, and Fe). It has been shown that the concentrations of lignin, lipids, phenolic compounds, Ca, Al, and Fe in the needles increase with age, while those of flavonoids, soluble and bound proanthocyanidins, N, P, K, Mg, Zn, and Mn decrease. The needles of juniper from spruce and birch forests differ in the contents of nutrient elements, which is explained by differences in the composition of soils. The contents of lignin, cellulose, and lipids in aging needles are lower in birch forests than in spruce forests.

Analysis of zonal patterns in the formation of synanthropic vegetation has shown that the intensity of manifestation of its zonal differentiation increases with the advancement of the successional stage of synanthropic communities. The rate of successional processes in these communities depends on the initial (potential) type of vegetation in the territory of the city.

Ferula xylorhachis Rech.f. is an endemic plant species belonging to the Apiaceae family and distributed in northeastern Iran. In the present study, we attempted to determine the factors with the greatest effects on the distribution of this species and to determine suitable regions for it based on current and future conditions. The Maximum Entropy method was used in the present study and the results indicated that the Mean Temperature of Wettest Quarter (48.2%), Precipitation of Wettest Quarter (49.1%), and Precipitation of Wettest Month (61.4%) are the most important factors in the current and in two future periods (2040 and 2070). The models suggest that suitable regions for the presence of this species will change over time and that the species will encounter limitations through changes such as moisture reduction. According to the A1B scenario, increases in greenhouse gases such as CO₂ and CH₄ will have direct effects on future precipitation and temperature and these factors will be important in determining species dispersion. Evaluation of important habitat factors using normal ecological methods will help in developing the best conservation programs in the future. Introducing species to new regions will help to protect them from the extinction risk caused by climate change.

The probable source of stone moroko, Pseudorasbora parva (Temminck & Schlegel, 1846), populations in lake- and stream-type Dnieper reservoirs was revealed. The dynamics and specific growth rates of these populations over 20 years were analyzed. The dynamic phase portrait method was used to determine the timing of stages in the process of invader naturalization and the periods when its populations were in equilibrium. The potential growth rates of P. parva populations in the Kremenchug and Dneprodzerzhinsk reservoirs were estimated.

Based on analysis of the frequencies of nonmetric cranial characters, the ratio of interpopulation and interspecific differences has been studied in populations of two genetically identified cryptic species of wood mice, A. uralensis and A. ponticus, living under different ecological conditions in the Northern Caucasus. Hybridization between these species has not been reported previously, but interspecific phenetic distances indicate that differences between them do not exceed the level characteristic of subspecies, with morphological differentiation between A. uralensis populations of the Central and Western Caucasus being weakly expressed. It is hypothesized that the low level of intra- and interspecific differences is explained by the sympatric and symbiotopic origin of both species in the Western Caucasus. This may account for the retention of their similarity in ecological requirements for the environment and, consequently, only slight morphological disparity in similar biotopes.

The population of foxes in the central regions of Yakutia has grown by a factor of four to five during the period from 2000 to 2011–2012, following an increase in the abundance of voles from the genus Microtus. A total of 130 carcasses of foxes taken in 2007–2012 have been examined. Age- and sex-related variation in morphological features has been described. The demographic structure of the population has been studied by estimating animal age from annual layers in the recording structures. Changes in female fertility and involvement in reproduction depending on age and feeding conditions have been analyzed. Changes in the composition of fox diet caused by long-term population depression in the mountain hare and their effect on the dynamics of fox abundance have been revealed. Age- and sex-related characteristics of the condition factor in foxes and sex-related differences in their dietary preferences have been demonstrated.

For the first time, satellite tagging of spotted seals (Phoca largha) has been performed in three regions of the Sea of Okhotsk: Chkalov Island in Sakhalin Bay, Ptichy Island, and the Bolshaya River mouth on the western coast of Kamchatka. As a result, regions inhabited by the seals in different periods of their life cycle and differences in the pattern of water area use by animals from different regions have been revealed. The seals from the western Kamchatka coast have covered greater distances during the observation period, compared to the animals from Sakhalin Bay. In the reproductive period, the seals from the western coast spread over the entire northern part of the Sea of Okhotsk, whereas the animals from the Sakhalin Bay move only to the Tatar Strait, the Sea of Japan. None of tagged seals has been located in the “reproductive center” at the eastern coast of Sakhalin. The seals tagged in different regions of the Sea of Okhotsk have never been located in the same place during the entire annual cycle, suggesting that the sea is inhabited by two reproductively isolated groups of ringed seals.

Accompanying the seasonal soil freeze-thaw cycle, microbial decomposition of litter exhibited different dynamic response to various snow thicknesses. In this study, we used real-time qPCR to investigate the abundance of bacteria, archaea, ammonia-oxidizing archaea (AOA) and bacteria (AOB), and the amoA gene transcripts, during the decomposition of dwarf bamboo (Fargesia nitida) litter under different snow patches at various snow-cover stages in an alpine forest on the eastern Tibetan Plateau in China. The effects of snow thickness were significant, with thicker snow patches resulting in higher microbial abundance and the amoA gene transcripts, while the degree of the effects were different. Compared with AOB, AOA were more abundant on the majority of sampling dates during the freeze-thaw period, and as well as their amoA gene transcripts. AOA are more persistent and abundant than AOB, and the higher AOA/AOB ratios were observed clearly in shrub litter and continued to decrease as the snow thickness increased, meanwhile gradually increased under uniform snow thickness over time. Our results suggested that the reduced seasonal snow cover and shortened freeze-thaw cycle periods caused by winter warming would significantly affect the ammonia oxidizers particularly tied to the ammonia oxidation process, and then could contribute to N cycle as related to litter in alpine forest ecosystems.