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卷 12, 编号 3 (2019)
- 年: 2019
- 文章: 11
- URL: https://journals.rcsi.science/1995-4255/issue/view/12655
Article
Role of Climate in the Spatial Structure of Vegetation of the Kodar-Kalar Orobiome
摘要
A bioclimatic substantiation of the spatial structure of vegetation of the Kodar-Kalar orobiome has been carried out based on altitudinal zonation of the vegetation and using the global climate model (BioClim) and data obtained from weather stations. The results show that mean annual temperatures and mean annual precipitation can be used to identify altitudinal vegetation belts and subbelts of the orobiome. Based on the quantitative data, such as the heat and moisture supply indices and derived parameters (potential evapotranspiration, Mezentsev’s moisture coefficient), a climatic ordination of geographic-genetic vegetation complexes has been performed for the Northern Transbaikalia for the first time. A scheme determining the vegetation diversity in the Kodar-Kalar orobiome has been proposed with allowance for vegetation development in various geographical variants within the integral system of bioclimatic factors. According to this system, vegetation complexes are differentiated according to the heat-supply and moisture-supply gradients. A complex analysis of bioclimatic characteristics has identified specific regional features in the structure and diversity of the vegetation of the Northern Transbaikalia mountain systems that confirm the contingency of the biota and abiotic conditions within orobiomes as the ecosystem complexes established at the regional level.
193-203
Reconstruction of the Holocene Dynamics of Forest Fires in the Central Part of Meshcherskaya Lowlands According to Antracological Analysis
摘要
This paper presents a reconstruction of the Holocene dynamics of forest fires and their influence on vegetation in the central part of Meshcherskaya Lowland. The studies are based on macrocharcoal and pollen analyses and radiocarbon dating of peat deposits from the Studencheskoe peatland. According to the results, changes in the structure of the plant cover were largely determined by the fire regime during the Holocene. In the period of high forest-fire intensity (∼9200–6400 calendar years BP), the study area was occupied by birch-pine forests. The role of spruce and broad-leaved species in forest stands was increased in the period with a low frequency of forest fires (∼6400–1400 calendar years BP). The influence of fires on vegetation increased after 1400 calendar years BP due to human impact. The results show that periods of increased fire frequencies occurred before the human occupation of the area and were determined by climatic causes.
204-212
Invasive Plant Species as Inhibitors of Restorative Successions
摘要
Communities of alien species-transformers able to slow down regenerative successions have been studied. The succession inhibition process was researched through the example of Solidago canadensis L. and Acer negundo L. Fallow and waste lands featuring edaphotopes with nonextreme moisture, pH, and nitrogen richness levels are typical habitats of communities of alien species-transformers. The overwhelming majority of identified phytocoenoses with the predominance of alien transformers are associated with old anthropogenic landscapes.
213-219
Ecology of Thrush Birds (Passeriformes, Turdidae) in Northwestern Siberia under Effects of Climate and Landscape Changes
摘要
The characteristics of the annual cycles and the ecology of thrush birds in the Lower Priobye and the Yamal Penisula have been compared. The factors limiting the species migration northward and the perspectives on the range expansion in the subarctic region under the effects of the climate-related warming trend are analyzed. Annual cycles in thrush birds are rather common, despite their wintering in the different parts of Eurasia. The variations in the pattern of the annual cycle generally occur in the postnesting period. These variations concern the age at the onset of the postjuvenile molt, the type of molt control (photoperiodic or endogenous), the degree of overlap of postbreeding molting and nesting, and the degree of the molt-migration overlap.
220-230
Ecological Status of Populations of the Most Common Bird Species in the Dark-Coniferous Taiga of Baikalia
摘要
Nesting home ranges of individual birds were regularly mapped in 2013 and 2014 from May to July along a permanent census route (3.15 km) in the dark-coniferous taiga on the southern slope of the bed of Lake Baikal. Based on the mapping results, the nesting densities and average sizes of the nesting home range of individual birds are estimated for each bird species and raster maps of spatial allocation (MSAs) at a scale of the raster grid of 50 × 50 m are obtained for each species. The degree of spatial conservatism (DSC) for each local population is inferred from the pairwise comparisons of the specific MSAs obtained on the same area (31.5 ha) in different years with the use of the Gamma rank correlation method. The dependence of the population habitat area on the DSC was demonstrated earlier (Cherenkov, 2017). The larger habitat area is found within the sample plot, an a less dependent individual spatial allocation within a population is observed in different years. Based on the estimated specific habitat areas, average sizes of the individual nesting home range, and estimated nesting density, the maximum possible nesting density and habitat saturation are calculated for each species. The population status is inferred from the degree of habitat saturation. Significant DSC estimates (p < 0.05) are obtained for nine species; their habitat areas and saturation are found. It is shown that habitat saturation in nonmigratory birds is twice as high an in migratory ones. On average, habitat saturation was 54–58% in nonmigratory birds and 26% in migratory ones (F = 9.1; p < 0.01). In the two species, the orange-flanked bush-robin (Tarsiger cyanurus Pallas, 1773) and taiga flycatcher (Ficedula (parva) albicilla Pallas, 1811), the habitat saturation is less than 20%, which indicates the presumably troubled status of their populations.
231-237
Experimental Investigation of Interrelations between Small Rodents and Red Wood Ants
摘要
Investigations of the mechanisms of the spatial-behavioral interaction of members of diverse and significant guilds such as red wood ants and small mammals have been started only recently, and many questions remain obscure. We have investigated interrelations between red wood ants Formica aquilonia Yarr and the common vole Microtus arvalis Pallas, the bank vole Myodes glareolus Schreber, and the pygmy wood mouse Sylvaemus uralensis Pallas in laboratory experiments. We first describe the defensive behavior of rodents and reveal a stereotype of the hunting behavior of the common vole towards dangerous insects. In all three rodent species, defensive behavior increases with an increase in the number of ants used in the tests, which corresponds to simulated natural situations with gradations of the dynamic density of insects. We speculate about the relationship between the defensive and hunting behavior of rodents towards red wood ants.
238-244
Dynamics of Species and Size Structures of Phytoplankton at Different Levels of Bottom-Up and Top-Down Effects in Experimental Conditions
摘要
An experimental study of the impacts of trophic conditions and the activity of zooplankton and fish on the phytoplankton structure has shown that, at the beginning of the experiment, the species and size structures of algae were dependent on the N : P ratio. This parameter causes the differences in phytoplankton structures between mesotrophic and eutrophic conditions so that, in mesotrophic conditions, the dominant taxa are diatoms, dinoflagellates and chrysophytes while, in eutrophic mesocosms, cyanobacteria are most abundant. Later on, the differences in N : P ratio in the treatments are smoothed out and the dominance shifts to large filamentous green algae. Fish reduce zooplankton control over phytoplankton, thus promoting the development of edible diatoms; this is most clearly manifested in eutrophic conditions.
245-253
Diversity of Planktonic Fauna of the Pechora River Delta
摘要
The structure and diversity of zooplankton of the mouth of the largest river in the European North, the Pechora, is studied. The river delta, an adjacent piece of the Pechora course, the estuary (Korovinskaya Bay), and lakes on its northern coast—in Timan Tundra—are in the studied region. In the delta of the Pechora River, the planktonic fauna is rich and unique in structure, in which rotifers (105 species) and cladocerans (55 species) prevailed; thermophilic invertebrates are present in zooplankton, but psychrophilic ones are revealed. Among copepods, brackish taxa and also a possible recent invader of the region (Eurytemora sp.) are found. The analysis of alpha and beta diversities of planktonic communities of the studied region shows the highest indexes for the delta water bodies relative to others and for the lake zooplankton in general. In our opinion, such diversity is due to a variety of environmental conditions and also features of gradients of the dominating environmental factors: temperature, anthropogenic, etc.
254-264
Assessment of the Quality of Bottom Sediments in the Middle Reaches of the Yenisei River by Allium test
摘要
The harmful potential of bulk bottom sediments of the Yenisei River has been assessed by the Allium test. Sediment samples have been taken in ten sites on a plot of about 100 km in length in the middle reaches of the Yenisei River affected by urban activity of the city of Krasnoyarsk and industrial plants. The samples of sediments differ considerably in the content of potentially toxic substances (heavy metals, artificial radionuclides, and organic pollutants) and nutrients and in physical properties. We use the mean length of onion root as an indicator of general toxicity, the mitotic index as an indicator of cytotoxicity, and the percentage of anatelophase cells in the apical root meristem with abnormal chromosomes as an indicator of genotoxicity. Both the stimulation and inhibition of indicator endpoints are revealed in sediment samples of the Yenisei River relative to the control (artificial sediments). An increased genotoxicity is recorded in the sample of sediments contaminated by a mixture of organic and chemical toxicants. A significant positive correlation between the percentage of abnormal cells and the content of copper and petrochemicals in the samples is revealed. No extremely strong reactions of onion endpoints to the quality of sediment samples are revealed, which is probably related to relatively low contamination of the sediments studied. This is in agreement with the data of chemical analyses. Based on the testing results, we can conclude that the endpoints of the Allium test are sensitive enough to the quality of bottom sediments of the Yenisei River and can be used for their biotesting.
265-274
Phytoplankton as an Indicator of Ecological State of the Neva River Estuary for 2011–2015
摘要
During the study period, the general pattern of distribution, species composition, and abundance of phytoplankton differed from those recorded previously. The greatest changes are observed in the central part of the northern coast of Neva Bay. As previously, the phytoplankton biomass is about 1 mg L−1 in the Neva Bay near eastern station 7 on the northern coast, while it is 2–3 times higher than the previously observed biomass near station 12. On the whole, the phytoplankton biomass in this area is 6.1 ± 2.9 mg L−1 in 2011–2015, which corresponds to the eutrophic level of productivity. The phytoplankton biomass of 15.8 mg L−1, which was recorded in late July 2015 and was dominated by algae Chlorophyta, characterizes this area of the Neva Bay as highly eutrophic. Against the background of currently observed processes of eutrophication in the Neva Bay and the eastern part of the Gulf of Finland, the summer phytoplankton (late July–early August) is dominated by different groups of algae. The mean biomass is 6–7 mg L−1 in the most productive area of the internal estuary (station 19). Periods of cyanobacterial water blooming at a biomass of over 22 mg L−1 are also most often recorded here.
275-279
Distribution of Chemical Elements between the Components of the Ecosystem of Arctic Lake Bolshoy Vudyavr (Khibiny, Murmansk Oblast)
摘要
The processes of accumulation of chemical elements and their distribution between abiotic (water and bottom sediments) and biotic (seston, zooplankton, and fish) components of the ecosystem of Lake Bolshoy Vudyavr, which has been contaminated by waste waters of the apatite-nepheline mining complex for a long time, are considered. The values of the biological accumulation of chemical elements and their enrichment of seston, zooplankton, fish, and bottom sediments are determined. The biogenic and terrigenous contribution of the chemical elements to the contribution of bottom sediments is estimated.
280-297