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71.
Changes in climate, land-use and pollution are having disproportionate impacts on ecosystems and biodiversity of arctic and mountain ecosystems. While these impacts are well-documented for many areas of the Arctic and alpine regions, some isolated and inaccessible mountain areas are poorly studied. Furthermore, even in well-studied regions, assessments of biodiversity and species responses to environmental change are biased towards vascular plants and cryptogams, particularly bryophytes are far less represented. This paper aims to document the environments of the remote and inaccessible Altai-Sayan mountain mires and particularly their bryofloras where threatened species exist and species new to the regional flora are still being found. As these mountain mires are relatively inaccessible, changes in drivers of change and their ecosystem and biodiversity impacts have not been monitored. However, the remoteness of the mires has so far protected them and their species. In this study, we describe the mires, their bryophyte species and the expected impacts of environmental stressors to bring attention to the urgency of documenting change and conserving these pristine ecosystems.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01596-w.  相似文献   
72.
Environmental Science and Pollution Research - The determination of trace metals and organic contaminants in environmental samples, such as water, air, soil, and sediment, is until today a...  相似文献   
73.

In recent decades, the problem of the constantly increasin level of anthropogenic load on the environment is becoming more and more acute. Some of the most dangerous pollutants entering the environment from industrial emissions are heavy metals. These pollutants are not susceptible to biodegradation over time, which leads to their accumulation in the environment in dangerous concentrations. The purpose of this work is to study the sustainability of cultivated and wild plants of the Poaceae family to aerotechnogenic pollution in the soil. The content of heavy metals in couch grass (Elytrigia repens (L.) Nevski), meadow bluegrass (Poa pratensis L.) and soft wheat (Triticum aestivum) plants grown in the impact zone of Novocherkassk Power Station has been analyzed. Contamination of cultivated and wild cereals with Pb, Zn, Ni and Cd has been established. It has been shown that the accumulation of heavy metals is individual for each plant species. An average and close correlation have been established between the total HM content and the content of their mobile forms in the soil and their content in plants. For the plants studied, the translocation factor (TF) and the distribution coefficient (DC) of HM have been calculated. The TF is formed by the ratio of the concentration of an element in the root plant dry weight to the content of its mobile compounds in the soil. The DC value makes it possible to estimate the capacity of the aboveground parts of plants to absorb and accumulate elements under soil pollution conditions and is determined as the ratio of the metal content in the aboveground biomass to its concentration in the roots. TF and DC values have shown a significant accumulation of elements by plants from the soil, as well as their translocation from the root system to the aboveground part. It has been revealed that even within the same Poaceae family, cultural species are more sensitive to man-made pollution than wild-growing ones.

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74.
Photodegradation products of the herbicide Goal active ingredient were obtained with a xenon lamp and analyzed using direct inlet mass spectrometry, MS/MS and GC/MS. A number of products were identified and their generation pathways were established to be mainly Ar—O bond cleavage, dechlorination and photocyclisation. The latter process gives chlorinated and unchlorinated dibenzofurans some of which may be toxic.  相似文献   
75.
Early family life is characterized by a close interaction between parents and their offspring. This needs to be disentangled when studying the ontogeny and evolution of a given behavior—e.g. via cross-fostering. But cross-fostering may change the expression of parent and offspring behaviors as they may respond to the novel environment. Furthermore, parent and offspring traits are potentially co-adjusted and cross-fostering may, therefore, introduce a costly mismatch. To study such consequences of cross-fostering, we created an experimental group (EG) of broods raised by foster parents from day 3 onwards and a control group of broods raised by their biological parents throughout. We tested offspring begging intensity in all broods and the provisioning of the EG-parents only, both on day 3 just before cross-fostering and then again on day 5. Costs were estimated in terms of growth and survival (offspring costs) and mass of a second clutch (parental costs). Offspring begging intensity varied with age, but this change was neither affected by cross-fostering per se nor by small-scale differences in parental provisioning between biological and foster parents. Similarly, the change in parental provisioning with offspring age among the EG-parents was not affected by the difference in begging between biological and foster nestlings. This lack in behavioral plasticity in response to cross-fostering did not entail costs to neither of the parties. Our results suggest a rather predetermined pattern of behavioral expression, which may be shaped by limits and costs to plasticity and/or an (apparent) lack of costs of a behavioral mismatch.  相似文献   
76.

Many studies have been devoted to investigation of toxic benzo(a)pyrene (BaP) compound, but studies involving changes at the cellular level are insufficient to understand the mechanisms of polycyclic aromatic hydrocarbons (PAHs) effect on plants. To study the toxicity of BaP, a model vegetation experiment was conducted on cultivation of spring barley (Hordeum sativum distichum) on artificially polluted BaP soil at different concentrations. The article discusses the intake of BaP from the soil into the plant and its effect on the organismic and cellular levels of plant organization. The BaP content in the organs of spring barley was determined by the method of saponification. With an increase in the concentration of BaP in the soil, its content in plants also rises, which leads to inhibition of growth processes. The BaP content in the green part of Hordeum sativum increased from 0.3 µg kg?1 in control soil up to 2.6 µg kg?1 and 16.8 µg kg?1 under 20 and 400 ng/g BaP applying in soil, as well as in roots: 0.9 µg kg?1, 7.7 µg kg?1, 42.8 µg kg?1, respectively. Using light and electron microscopy, changes in the tissues and cells of plants were found and it was established that accumulation of BaP in plant tissues caused varying degrees of ultrastructural damage depending on the concentration of pollutant. BaP had the greatest effect on the root, significant changes were found in it both at histological and cytological levels, while changes in the leaves were observed only at the cytological level. The results provide significant information about the mechanism of action of BaP on agricultural plants.

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77.
Environmental Geochemistry and Health - Nowadays, nanotechnology is one of the most dynamically developing and most promising technologies. However, the safety issues of using metal nanoparticles,...  相似文献   
78.
Journal of Material Cycles and Waste Management - The substitution of standard clays to residues, in this case copper smelter slag and fly ashes coming from the incineration process of MSW in...  相似文献   
79.
Maintaining a reasonably low cutting tool wear when producing forming tools is a general challenge in the development of new forming tool materials. The tool life of a hot forming tool steel (H13) has been significantly improved by reducing its Si-content from 1.0 to 0.06 wt.%. However, this modified H13 (MH13) also displays a reduced cutting tool life due to higher cutting forces and a stronger tendency to form built up layers (BUE) on the cutting edge. This paper explains why.Gleeble tests of MH13 revealed a significantly higher flow stress in the 820–900 °C temperature interval in MH13 compared to H13. Thermo-Calc simulations showed that when reducing the Si-content from 1.0 to 0.06 wt.% the initial temperature for ferrite-to-austenite transformation (A1) was reduced from 900 °C to 820 °C. Knowing that austenite has totally different mechanical and thermal properties than ferrite, the difference in A1 between the two steels explains the higher cutting forces and higher tendency for BUE-formation. The conclusion is that the difference in machinability between H13 and MH13 is primarily related to their difference in A1.An attempt was also made to find a new tool material composition that can combine the wear resistance of MH13 and the good machinability of H13. Thermo-Calc simulations were performed with slightly modified alloying content without changing its properties as a good forming tool material, with the aim to increase A1. For instance, reducing the Mn content from 0.5 to 0.05 wt.% proved to increase A1 from 820 to 850 °C.  相似文献   
80.
This paper reports (222)Rn concentrations in ground and drinking water of nine cities of Chihuahua State, Mexico. Fifty percent of the 114 sampled wells exhibited (222)Rn concentrations exceeding 11Bq/L, the maximum contaminant level (MCL) recommended by the USEPA. Furthermore, around 48% (123 samples) of the tap-water samples taken from 255 dwellings showed radon concentrations over the MCL. There is an apparent correlation between total dissolved solids and radon concentration in ground-water. The high levels of (222)Rn found may be entirely attributed to the nature of aquifer rocks.  相似文献   
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