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Том 74, № 5 (2019)
- Год: 2019
- Статей: 5
- URL: https://journals.rcsi.science/0147-6874/issue/view/10704
Ecological Safety
Estimating the Toxicity and Biological Availability for Interaction Products of Metallic Iron and Humic Substances
Аннотация
This article considers the influence that suspensions of nanoparticles (sized from 10 to 60 nm) of iron oxo-compounds in different oxidation states have on biological objects. The suspension is formed by the interaction of metallic iron with aqueous solutions of humic substances. Based on the example of green microalgae Scenedesmus quadricauda (Turp.) Breb., it is shown that suspensions that contain iron oxo-compound nanoparticles stabilized with humic substances at an iron concentration from 0.14 to 2036 µM do not have a toxic effect on microalgae. The availability of iron contained in the suspensions was evaluated in the experiment on sprouts of wheat Triticum aestivum L., which had been grown under iron-deficient conditions. The root uptake of the ionic form of iron contained in the suspension was confirmed. It is shown that the studied suspensions of iron nanoparticles stabilized by humic substances accumulate on the surface of plant roots. These suspensions are supposed to be a source of iron with prolonged action for plants.
193-198
Applying the Method of Fluorescence Spectroscopy to Study Dissolved Organic Matter in Waters of the Moskva River
Аннотация
The applicability of fluorescence spectroscopy for studying the dissolved organic matter in the Moskva River has been shown. The most typical surface water fluorophores—humic and fulvic acids and protein substances—have been revealed in the studied water samples. The fluorescence intensity depends on the sampling site and indicates the contamination rate. The dynamics of the composition and fluorescence parameters of river waters varies with respect to the sampling period. While the concentration of dissolved organic matter and chemical oxygen demand increases from October until November, specific ultraviolet absorbance, biological oxygen demand, and fluorescence of humic acids significantly decrease. The observed dynamics does not depend on the sampling site, which confirms the effect of climatic conditions. Statistically significant (p < 0.05) correlations between spectral and chemical parameters of water contamination have been revealed. Fluorescence intensity, tryptophan-containing organic substances, fulvic acids, and values of biological index correlate (r = 0.63–0.92) with the content of ammonium and phosphate ions. The fluorescent index A may be used to determine the zone of the effect of anthropogenic biological impurities on the status of waters of the Moskva River.
199-207
Influence of Hydrogen Fluid on Plants in Natural Conditions and a Model Experiment
Аннотация
In places of hydrogen emanation, prolonged exposure to significant concentrations of hydrogen under natural conditions led to the inhibition or death of agricultural plants. Under the conditions of model experiments, it was shown that plants in a short-term current of hydrogen experience stress, which negatively affects their physiological functions. Different types of plants reacted differently both to the effect of molecular hydrogen and to the removal of its load. In experiments with watercress, plants did not recover after the removal of the hydrogen load but died after a triple exposure. Wheat was less sensitive; the plants were only stably (30%) depressed during the whole observation period.
208-213
A Case of Soil Erosion’s Economic Assessment
Аннотация
The article contains a detailed review of existing Russian and foreign approaches for the economic assessment of soil erosion. In Russia, the costs of full soil restoration are determined based on the full time period needed for complete restoration of the soil’s original state. If the costs are difficult to assess, the damage of soil erosion is estimated using the equations that include the area and extent of erosion processes. These calculations include an obligatory element of “lost profit,” i.e., profit lost due to the erosion process. In environmental and economic studies in other countries, soil erosion is most often seen as a global problem for sustainable agriculture, resulting in reduced soil productivity and loss of crop yields and income. Based on the analysis of “Methodological Recommendations for the Identification of Degraded and Contaminated Land” [13] and soil classifications by the degree of washout [17, 21, 22], the associations between the degrees of degradation and the degree of washout of sod-medium-podzolic soils of the Training and Experimental Soil-Ecological Center of Moscow State University were determined. The degree of damage to these soils from erosion processes was then calculated. It was also useful to estimate the amount of lost educational resources in this area, because it is used by the Department of Soil Sciences of Moscow State University. The method of J. von Braun (in terms of scenarios involving ecosystem services) was applied and it was proven that a program for the eroded soil’s restoration should be adopted.
214-220
The Modern Radioecological Situation in Pine Ecosystems of the Southeastern Part of Moscow Oblast
Аннотация
The radioecological situation in pine biogeocenosis in the southeastern part of Moscow oblast (based on the example of Ramensky raion) is analyzed. Contamination levels of soil, trees, grass, moss, and mushrooms by the natural (226Ra and 232Th) and technogenic (137Cs) radionuclides are assessed. It is shown that the radiation situation in the study area is classified as safe according to the main indicators.
221-225