scholarly journals Gross chemical composition of dark gray podzolized soils of Small Polissya and its transformation caused by human impact

Author(s):  
Volodymyr Haskevych

Dark gray podzolized soils (Phaeozems Albic (PHad), WRB, 1998) are typical for the natural area of Pasmove Pobuzhia physiographic oblast of the Small Polissya. The investigation of the transformation of the gross chemical composition of dark gray podzolized soils of Small Polissya due to erosion processes conducted for the first time, confirming the relevance of the research. Standard methods of research were used in the investigation of the gross chemical composition of dark gray podzolized soils. The research results have been worked out according to the methodology of Y. Arynushkina and N. Myakina. According to the research, SiO2 dominated in all genetic soil horizons. Its content in the humus-accumulative horizon is 82.06 % by weight of calcined soil, decreasing to 74.45 % in soil rock. Different distribution of silica in the soil profile indicates the poor process of podzolic soil development. Among oxides in the soil profile dominates Al2O3, it contents in the humus-accumulative horizon is 8,10 %. A slight accumulation of Aluminium oxides was found in horizon confirming weak profile differentiation by eluvial-alluvial type. Content of Fe2O3 oxides in the soil profile is low variadic in the arable layer and the content is 2.30 %. Oxides of CaO content ranges from 0,75 % in the horizon He to 6,17 % in soil rock, and the content of oxides MgO, respectively, from 0.65 % to 1.06 %. Gross content of iron oxides, titanium, manganese, sodium, potassium, phosphorus and sulfur in the soil genetic horizons ranges from 0,04 % to 2,39 %. The estimated ratio between the major oxides and their profile distribution also confirm weak profile differentiation of dark gray podzolized soils. The content of the constitutional water of humus He horizon of dark gray podzolized soils is 1.57 %. Increase of constitutional water in the middle of the profile may be caused by increasing of internally soil deflation processes. This is also confirmed by the growth of silica coefficient changes of the soil at the same depth. In eroded dark gray podzolized soils of the arable layer the content of SiO2 is decreasing, reaching values of 79,63–80,84 % in strongly eroded. The content of other oxides tends to increase as well as decrease comparing to non-eroded soil. The correlation between wash out level and molar magnitude ratios The correlation between wash out level and molar magnitude ratios is being observed in eroded soils. With erodation increase the ratio of SiO2: Al2O3 and SiO2: R2O3 is being narrowed, which indicates accumulation in arable horizons of aluminium, including oxides in general, compared with non-eroded types. The content of the constitutional water increases and expands the coefficient of the silica changes, indicating the strengthening of internally soil deflation processes in the arable layer of erosion-degraded dark gray podzolized soils compared to non-eroded types. Key words: dark gray podzolized soils, gross chemical composition, oxides, degradation.

2001 ◽  
Vol 56 (10) ◽  
pp. 990-996 ◽  
Author(s):  
Falk Lissner ◽  
Frank A. Weber ◽  
Thomas Schleid

Single crystals of Sm2S2-xSe1+x (0.1 ≤ x < 0.2) have been obtained for the first time through the oxidation of KSm2Cl5 with an excess of sulfur and selenium in equimolar amounts at 850 °C after seven days in evacuated silica tubes. They emerged as almost black, in thin layers deep red, lath-shaped needles (A and U type, respectively) as well as red, bead-shaped polyhedra (C type) of the gross chemical composition Sm2S2Se according to X-ray structure analyses. A much simpler method of synthesis is based on the direct fusion of the elements (samarium, sulfur and selenium) in appropriate molar ratios (2:2:1) in the presence of NaCl as a flux under otherwise analogous conditions (silica tubes, 7 d, 850 °C). A-Sm2S1.82Se1.18 crystallizes orthorhombically (a = 753.1(3), b = 401.9(1), c = 1565.8(6) pm, Z = 4) in the space group Pnma with the α-Gd2S3-type structure. Two crystallographically different Sm3+ cations are coordinated by eight (Sm1) and seven (Sm2) Ch2- anions (S2- and Se2-) as biand monocapped trigonal prisms, respectively. C-Sm2S1.90Se1.10 adopts the cubic γ-Ce2S3-type structure (I4̅3d; a = 858.7(2) pm, Z = 5.333) with trigon-dodecahedrally coordinated Sm3+ cations (CN = 8 ). Finally, U-Sm2S1.84Se1.16 with the orthorhombic U2S3-type structure (Pnma; a = 1105.3(6), b = 399.2(1), c = 1074.0(5) pm, Z = 4) exhibits two crystallographically different Sm3+ cations again, which are coordinated by seven (Sm1) and seven plus one (Sm2) Ch2- anions, respectively. The preferential occupation of S _ and Se2- anions at only one in the C-type, but three anionic sites each in the A- and U-type crystal structures of Sm2S2-xSe1+x (0 .1 ≤ x < 0.2 ) is discussed.


2002 ◽  
Vol 57 (11-12) ◽  
pp. 990-993 ◽  
Author(s):  
Guddadarangavvanahally K. Jayaprakasha ◽  
Lingamallu Jaganmohan Rao ◽  
Kunnumpurath K. Sakariah

The hydro-distilled volatile oil of the Cinnamomum zeylanicum (C. zeylanicum) buds was analyzed using GC and GC-MS for the first time. Thirty-four compounds representing ≈ 98% of the oil was characterized. It consists of terpene hydrocarbons (78%) and oxygenated terpenoids (9%). α-Bergamotene (27.38%) and α-copaene (23.05%) are found to be the major compounds. A comparison of the chemical composition of the oil was made with that of flowers and fruits.


2013 ◽  
Vol 13 (15) ◽  
pp. 7875-7894 ◽  
Author(s):  
I. El Haddad ◽  
B. D'Anna ◽  
B. Temime-Roussel ◽  
M. Nicolas ◽  
A. Boreave ◽  
...  

Abstract. As part of the FORMES summer 2008 experiment, an Aerodyne compact time-of-flight aerosol mass spectrometer (cToF-AMS) was deployed at an urban background site in Marseille to investigate the sources and aging of organic aerosols (OA). France's second largest city and the largest port in the Mediterranean, Marseille, provides a locale that is influenced by significant urban industrialized emissions and an active photochemistry with very high ozone concentrations. Particle mass spectra were analyzed by positive matrix factorization (PMF2) and the results were in very good agreement with previous apportionments obtained using a chemical mass balance (CMB) approach coupled to organic markers and metals (El Haddad et al., 2011a). AMS/PMF2 was able to identify for the first time, to the best of our knowledge, the organic aerosol emitted by industrial processes. Even with significant industries in the region, industrial OA was estimated to contribute only ~ 5% of the total OA mass. Both source apportionment techniques suggest that oxygenated OA (OOA) constitutes the major fraction, contributing ~ 80% of OA mass. A novel approach combining AMS/PMF2 data with 14C measurements was applied to identify and quantify the fossil and non-fossil precursors of this fraction and to explicitly assess the related uncertainties. Results show with high statistical confidence that, despite extensive urban and industrial emissions, OOA is overwhelmingly non-fossil, formed via the oxidation of biogenic precursors, including monoterpenes. AMS/PMF2 results strongly suggest that the variability observed in the OOA chemical composition is mainly driven in our case by the aerosol photochemical age. This paper presents the impact of photochemistry on the increase of OOA oxygenation levels, formation of humic-like substances (HULIS) and the evolution of α-pinene SOA (secondary OA) components.


Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2949
Author(s):  
Juan I. Burneo ◽  
Ángel Benítez ◽  
James Calva ◽  
Pablo Velastegui ◽  
Vladimir Morocho

Chemical compositions of plants are affected by the initial nutrient contents in the soil and climatic conditions; thus, we analyzed for the first time the effects of soil and leaf nutrients on the compositions of the essential oils (EOs) of Siparuna muricata in four different localities in Ecuador. EOs were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) and a gas chromatography/flame ionization detector (GC/FID). Enantiomeric distribution by GC/MS was determined, modifying the enantiomeric separation of β-pinene, limonene, δ-elemene, β-bourbonene, cis-cadina-1 (6), 4-diene and atractylone. A total of 44 compounds were identified. The most representative for L1 were guaiol, atractylone and 4-diene; for L2, cis-cadina-1(6),4-diene and myrcene; for L3, atractylone, myrcene and germacrene B; and finally, L4 germacrene B, myrcene and cis-cadina-1(6),4-diene. Correlations between soil- leaf chemical elements such as Al, Ca, Fe, Mg, Mn, N and Si in the different localities were significant with chemical composition of the essential oil of Siparuna muricata; however, correlations between soil and leaf K, P, and Na were not significant. Cluster and NMDS analysis showed high dissimilarity values of secondary metabolites between four localities related with changes in soil- leaf nutrients. Thus, the SIMPER routine revealed that not all secondary metabolites contribute equally to establishing the differences in the four localities, and the largest contributions are due to differences in guaiol, cis-cadina-1(6),4-diene, atractylone and germacrene. Our investigation showed for the first time the influences of altitude and soil- leaf chemical elements in the chemical composition of the EOs of S. muricata.


Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1471
Author(s):  
Maria V. Korneykova ◽  
Anastasia S. Soshina ◽  
Andrey I. Novikov ◽  
Kristina V. Ivashchenko ◽  
Olesya I. Sazonova ◽  
...  

For the first time, a mycological analysis of outdoor urban environment (air, leaves, sealed surfaces) was carried in the cities of subarctic (Murmansk) and temperate (Moscow) climatic zones. The chemical composition of dust deposited on leaves of dominant tree species was taken as an indicator of the air quality. Assessment of the complex impact of factors (climate zone, type of substrate, anthropogenic load) on the quantitative and qualitative parameters of mycobiome was performed. Compared to Moscow, Murmansk was characterized by an increased number and concentrations of pollutants in the deposited dust. The number of culturable airborne fungi in Murmansk was substantially lower than in Moscow. Half of the species belonged to the opportunistic in both cities. Most dangerous opportunistic fungi were absent in the air of recreational zones but present on leaves surface and in road dust in all assessed zones of the cities. Dust chemical composition affected the diversity of fungi species. While the relationship of biological parameters with concentration of potentially toxic metals was generally negative, Cd increased the fraction of opportunistic fungi in road dust. The study revealed an importance of substrate in determining the sensitivity of outdoor mycobiome to pollution and highlighted its biological characteristics sensitive to climate.


Author(s):  
O. Glotka ◽  
V. Olshanetskii

Purpose. The aim of the work is to obtain predictive regression models, with the help of which, it is possible to adequately calculate the mechanical properties of nickel-based superalloys of equiaxial crystallization, without carrying out preliminary experiments. Research methods. To find regularities and calculate  the latest CALPHAD method was chosen, and modeling of thermodynamic processes of phase crystallization was performed. Results. As a result of experimental data processing, the ratio of alloying elements Kg¢ was proposed for the first time, which can be used to assess the mechanical properties, taking into account the complex effect of the main alloy components. The regularities of the influence of the composition on the properties of heat-resistant nickel alloys of equiaxial crystallization are established. The analysis of the received dependences in comparison with practical results is carried out. The relations well correlated with heat resistance, mismatch and strength of alloys are obtained. Scientific novelty. It is shown that for multicomponent nickel systems it is possible with a high probability to predict a mismatch, which significantly affects the strength characteristics of alloys of this class. The regularities of the influence of the chemical composition on the structure and properties of alloys are established. A promising and effective direction in solving the problem of predicting the main characteristics of heat-resistant materials based on nickel is shown Practical value. On the basis of an integrated approach for multicomponent heat-resistant nickel-based alloys, new regression models have been obtained that make it possible to adequately predict the properties of the chemical composition of the alloy, which made it possible to solve the problem of computational prediction of properties from the chemical composition of the alloy. This allows not only to design new nickel-based alloys, but also to optimize the composition of existing brands.


2021 ◽  
Vol 262 ◽  
pp. 03023
Author(s):  
Aida Tamahina ◽  
Urfa Turan Ogly Turabov

The pasture digression of meadows followed by soil deflation is one of the pressing environmental problems. This problem is typical for mountain pastures that are constantly in economic circulation. The article presents the results of a geobotanical survey of the Zolsky pastures on the territory of the Kabardino-Balkarian Republic in 2018-2020. The results of a geobotanical survey show that the pasture phytocenoses are characterized by high floristic diversity due to the heterogeneity of edaphic and orographic factors. The flora of the pastures is represented by postwood moist sedgy-and-tussock-grass, mesophilic woodreed-and-agrostidinic grass, cereal forb, forbs cereal mesophilic and subalpine meadows, low sedgy meadow steppes. The average yield for the pasture period varies from 7.2 to 16.6 centners/ha of dry eaten mass. The consequence of prolonged pasturage and excessive pasture load was a decrease in alpha and beta diversity, the formation of low-productive secondary plant communities of non-food, poisonous and weed grasses, the destruction of sod and soil outcropping. Restoration of degraded pasture ecosystems is possible on the basis of ecological intensification, which provides for the regulation of pasture loads, adherence to grazing terms, phytomelioration using perennial grasses, and short-term isolation of pastures from grazing. This will prevent erosion processes, increase biodiversity, productivity, forage value of grass stand and stability of pasture ecosystems.


Author(s):  
Natalya V. Plikina ◽  
◽  
Andrey N. Efremov ◽  
Galina V. Samoilova ◽  
◽  
...  

The results of monitoring the populations of protected plant species of the Omsk region in the territories of Russko-Polyansky municipal district are presented. During the research 210 cenopopulations of 32 of protected plants species were found in total. The locations of 20 protected species at the regional level were identified at the studied district for the first time: Adonis villosa, A. volgensis, Allium clathratum, Alyssum lenense, Astragalus buchtormensis, A. stenoceras, Dianthus ramosissimus, Ephedra distachya, Fritillaria meleagroides, Hedysarum gmelinii, Iris halophila, I. humilis, Linum perenne, Orostachys spinosa, Puccinellia gigantea, Ranunculus polyrhizos, Stipa lessingiana, Tanacetum millefolium, Tulipa patens, Valeriana tuberose. Two species (Stipa pennata, S. zalesskii) have considered as federal protected objects. Three sites were identified where the maximum number of protected species in natural habitats is concentrated, one of them has now received the status of a specially protected natural area of local and regional significance.


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