Том 8, № 1 (2018)

This paper reviews the main historical stages of the development and implementation of the largest environmental project of the late 20th century—the “General Plan to Combat Desertification of Black Lands and Kizlyar Pastures.” The goal of this project was to implement a scientifically grounded set of measures to stop desertification processes, improve the economic state of pastures, increase their fertility, and protect lands. The implementation of the general plan has led to the performance of agroforestry works in an area of more than 7000 km², the fixing of more than 4000 km² of mobile sands, and the restoration of more than 2500 km² of pastures. According to the forecasts, if all of the measures stipulated by the general plan were observed, the area of the ecological disaster zone would decrease and then completely disappear. A study conducted with Landsat satellite images showed that this forecast has partially come true: the area of open sands that was recorded in the test plot in 2016 (27.3 km²) is only 1% of the open sands area recorded in 1975, which is a consequence of the implementation of the general plan, a number of environmental measures, and favorable climate fluctuations.

The results of monitoring of the climatic and natural conditions of the semidesert in the Dzhanybek station of the Institute of Forest Science of the Russian Academy of Sciences (IFS RAS) in the northern Caspian region are presented. Monitoring studies have been conducted since the middle of the past century. The goal of the observations was to determine the implications of climate change for the habitat, profile, and state of the animated nature of the ecosystem components. In the course of the process, the station’s team observed an increase in the average annual air temperature by 2.2°C and the periodicity in the territory wetness caused by variations in the amount of precipitates. Moreover, in the period of increased wetness from 1980 to 1994, the ground water and water body levels increased, herbaceous communities and cereal crops became more yielding, and wild hoofed animals (saigas) proliferated as well. In the period of drought from 1995 to 2009, the spring melt water runoff attenuated, water bodies shoaled and dried, and dry spells repeated from year to year, which negatively affected the development of the ecosystem components. On the whole, the climate changes have not disturbed the dynamic balanced state of the natural ecosystems (e.g., yield of virgin land phytocenoses, wild animal stock); however, long dry spells have irreversibly aggravated the state of man-made forests and even caused their extinction and long-term cereal crop failures on zonal soils, which has led to unstable agricultural product outputs. The research results reveal the need to switch to adaptive fine-contour or focal farming suited most fitted for the climatic and natural condition of the region.

Compilation of the Red Data Books of soils for the subjects of the Russian Federation will provide for conservation of natural diversity of soils in regions significantly modified by management activities. When compiling the list of the reference soils it is proposed to focus primarily on soils, which are typical for provinces of soil-ecological zoning and to identify reference soils within protected nature areas. The research of virgin soils included in the Red Data Book of the Rostov oblast showed that their characteristics can be used as reference in the course of soil monitoring. The maintenance of the fallow regime in soils promotes restoration of their humus condition. In virgin and fallow chernozems, the weighted mean humus content (for a 25-cm thick soil layer) is by 0.7–3.0% greater than that in the arable analogs. It is demonstrated that the available normative documents are not applicable for assessing the degree of pollution of regional soils with heavy metals. To fulfil this task it is proposed to use regional background concentrations established for virgin soils with similar typology and textural composition, while taking into account natural variation of characteristics.

Centers of ore-mining technogenesis and their specific landscapes have been identified within the Karachai-Cherkess Republic and the Republic of Dagestan. Elements of the technogenic ore-mining landscape have been revealed to have a negative impact on the environment within the identified centers. It is shown that mining works are one of the main sources of ecological tension and potable fresh water pollution in highly hazardous copper-pyrite deposits. A range of mine engineering, geoecological, and social problems of the mining republics of the northern Caucasus are evaluated.

An ecological and geographical analysis of the distribution of poisonous plants in the regional biomes of Russia and the effect of arid conditions on it are presented. On the territory of Russia, 82 of the most toxic species of vascular plants (belonging to 34 families) were identified; of them, 55 were poisonous species of the genus Aconitum. Cartographic analysis demonstrated that the smallest number of poisonous plant species (excluding species of the genus Aconitum) is confined to the plain biomes of the forest-tundra and tundra, and the largest number of such species grows in lowland steppe biomes. In the lowland desert biome and in some mountain biomes, the number of poisonous plant species is also significant but is slightly lower than in the steppe biomes. The maximal number of species of the genus Aconitum was detected in the mountainous Far Eastern biomes. Correlation analysis of the relationship between the number of plant species and climatic factors revealed the maximal correlation between the total number of poisonous plant species (excluding species of the genus Aconitum) with the average annual air temperature.

The impact of ecological factors (abiotic and biotic) on some fishery-biological parameters is studied with the raising of acipenserids under arid conditions with a closed cycle of water supply (CCWS). The elements of a CCWS include the temperature, pH, oxygen concentration, and an artificial environment with varying oxygen supply. It was found that a significant increase in the content of a marker of oxidative stress is established in the blood of fish raised under a CCWS with an increased oxygen content by the end of experiment (four weeks). An oxygen content below 70% retards growth in the starlet, as food consumption is noticeably decreased. To obtain a high biomass in CCWS complexes, it is necessary to set the water temperature to 21–22°C in the basins of semidesert climate conditions and to have a stocking density of 60 kg/m³ for the commercial growth of sterlet.