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The aim of the study was to investigate how the quality of snow varies within a city. The study area is situated in the Luleå municipality, in northern Sweden (lat. 65°35′N and long. 22°10′E). For this study, the city was divided into three different types of areas: housing areas, city centre and outskirts. In one area of each type, sampling sites were selected. Snow samples were taken at nine occasions, once every fourteenth day in the city centre and in the housing area. Analyses were carried out for pH, conductivity, suspended solids and both the total and dissolved concentration of phosphorus and selected metals. It was concluded that traffic or activities related to traffic were a major source of heavy metals and phosphorus in urban snow, both in the city centre and in the housing area. Also, the type of area and the design of the street were important for the quality of snow. A clear relation was found between the pH and the quantity of suspended solids in the snow. Higher pH values were found in snow samples from sites with higher traffic loads, and lower pH values at sites, which were the no-traffic sites, with small quantities of particles. The particulate and dissolved substances in the snow behaved in different ways. 相似文献
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V. S. Anisimov L. N. Anisimova L. M. Frigidova D. V. Dikarev R. A. Frigidov Yu. N. Korneev A. I. Sanzharov S. P. Arysheva 《Eurasian Soil Science》2018,51(4):407-417
The mobility and migration capacity of Zn in the soil-plant system were studied in a series of pot experiments with barley as a test plant. The parameters of Zn accumulation depending on the metal concentrations in soils and soil solutions were estimated by soil and water culture methods. Experiments with barley in water culture were performed on a nutrient (soil) solution extracted from soddy-podzolic soil (Albic Retisol (Loamic, Ochric)) to which Zn2+ was added to reach working concentrations increasing from 0.07 to 430 μM. Different responses of barley plants to changes in the concentration of Zn in the studied soil were identified. Ranges of the corresponding concentrations in the soil and aboveground barley biomass were determined. Parameters of Zn accumulation by test plants were determined depending on the metal content in soddypodzolic soil and the soil solution. A new method was proposed for evaluating the buffer capacity of soils with respect to a heavy metal (Zn) using test plants (BCS(P)Zn). The method was used to evaluate the buffering capacity of loamy sandy soddy-podzolic soil. The considered methodological approach offers opportunities for using data obtained during the agroecological monitoring of agricultural lands with heavy metals (HMs), including the contents of exchangeable HMs and macroelements (C and Mg) in soils and concentrations of HMs and (Ca + Mg) in plants, in the calculation of the buffering capacity of the surveyed soils for HMs. 相似文献
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T. S. Demkina A. V. Borisov V. A. Demkin T. E. Khomutova T. V. Kuznetsova M. V. El’tsov S. N. Udal’tsov 《Eurasian Soil Science》2017,50(7):791-804
Diagnostic features of a catastrophic aridization of climate, desertification, and paleoecological crisis in steppes of the Lower Volga region have been identified on the basis of data on the morphological, chemical, and microbiological properties of paleosols under archeological monuments (burial mounds) of the Middle Bronze Age. These processes resulted in a certain convergence of the soil cover with transformation of zonal chestnut (Kastanozems) paleosols and paleosolonetzes (Solonetz Humic) into specific chestnut-like eroded saline calcareous paleosols analogous to the modern brown desert-steppe soils (Calcisols Haplic) that predominated in this region 4300–3800 years ago.1 In the second millennium BC, humidization of the climate led to the divergence of the soil cover with secondary formation of the complexes of chestnut soils and solonetzes. This paleoecological crisis had a significant effect on the economy of the tribes in the Late Catacomb and Post-Catacomb time stipulating their higher mobility and transition to the nomadic cattle breeding. 相似文献
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Granado-Lorencio F Donoso-Navarro E Sánchez-Siles LM Blanco-Navarro I Pérez-Sacristán B 《Journal of agricultural and food chemistry》2011,59(21):11819-11824
Bioactive compounds are used in the design and development of new food products with potential health benefits, although little is known regarding their bioavailability and interactions. This study assessed the stability, in vitro bioaccessibility, and human bioavailability of β-cryptoxanthin from β-cryptoxanthin-rich drinks with and without added phytosterols developed for this purpose. The developed drinks showed no difference in the content of β-cryptoxanthin, and they were stable over 6 months. In vitro, hydrolysis of β-cryptoxanthin esters and the amount of free β-cryptoxanthin at duodenal and micellar phases were similar regardless of the presence of phytosterols. In the human study, the daily intake provoked significant increments of β-cryptoxanthin in serum regardless of the type of the drink. In conclusion, in vitro and in vivo human studies have shown that the bioavailability of β-cryptoxanthin is not significantly affected by the presence of phytosterols when they are simultaneously supplied in a drink. 相似文献
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Bronnikova M. A. Agatova A. R. Lebedeva M. P. Nepop R. K. Konoplianikova Yu. V. Turova I. V. 《Eurasian Soil Science》2018,51(12):1381-1396
Eurasian Soil Science - The results of morphosubstantive genetic study of a soil–sedimentary sequence with four buried soils in the Boguty River basin (southeastern Altai) are discussed. A... 相似文献
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The method of phytoindication of the soil water status and nutrient supply was applied to natural and oil-contaminated soils in the middle reaches of the Ob’ River. These soil characteristics were indirectly assessed using the ecological scales developed by L. G. Ramenskii. On this basis, changes in the soil water status and nutrient supply under the impact of soil contamination with oil and oil products were estimated for the particular soil and landscape conditions 相似文献
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D. A. Kaverin A. V. Pastukhov E. M. Lapteva C. Biasi M. Marushchak P. Martikainen 《Eurasian Soil Science》2016,49(5):498-511
The morphology and properties of the soils of permafrost peatlands in the southeast of the Bol’shezemel’skaya tundra are characterized. The soils developing in the areas of barren peat circles differ from oligotrophic permafrost-affected peat soils (Cryic Histosols) of vegetated peat mounds in a number of morphological and physicochemical parameters. The soils of barren circles are characterized by the wellstructured surface horizons, relatively low exchangeable acidity, and higher rates of decomposition and humification of organic matter. It is shown that the development of barren peat circles on tops of peat mounds is favored by the activation of erosional and cryogenic processes in the topsoil. The role of winter wind erosion in the destruction of the upper peat and litter horizons is demonstrated. A comparative analysis of the temperature regime of soils of vegetated peat mounds and barren peat circles is presented. The soil–geocryological complex of peat mounds is a system consisting of three major layers: seasonally thawing layer–upper permafrost–underlying permafrost. The upper permafrost horizons of peat mounds at the depth of 50–90 cm are morphologically similar to the underlying permafrost. However, these layers differ in their physicochemical properties, especially in the composition and properties of their organic matter. 相似文献
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Eurasian Soil Science - The accumulation of polycyclic aromatic hydrocarbons (PAHs) in plants and peat of three natural subzones—forest-tundra, southern tundra, and northern tundra—is... 相似文献
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T. Matys Grygar T. Nováková M. Mihaljevič L. Strnad I. Světlík L. Koptíková L. Lisá R. Brázdil Z. Máčka Z. Stachoň H. Svitavská-Svobodová D.S. Wray 《CATENA》2011
Sediment profiles from the floodplain of Morava River in the Czech Republic have been collected from exposed river banks (4–6 m long sections) and cores (2–4 m deep) and investigated using a set of geochemical proxies validated by granulometry and conventional geochemical analysis, outlined in our previous paper. The work was conducted to evaluate the increase in sedimentation rate during Medieval and modern time periods. Correlation of sediments along the current channel belt allows identification of two most important synchronous changes in the channel structure over the past 1300 years: in the 13th century and at the end of the 16th century. These changes could be related to central European climatic extremes rather than to land cover/land use practises. Analysis of the pollen record in peaty deposits at the floodplain edge allows excluded dramatic deforestation in Medieval times. Maps of the area from the last five centuries revealed direct and indirect signs of past avulsions and clearly show how the original multichannel system was transformed into a single meandering channel in the early 20th century. The extrapolated aggradation rate (net vertical accretion of floodplain fines except for levee sediments) increased from 0.2–0.3 cm/year in 700 AD to 0.3–0.4 cm/year in 2000 AD depending on the grain size of the sediment. This is the smallest yet reported enhancement of siliclastic deposition, although Morava River watershed has been intensively used for agriculture and its land cover has changed in a manner similar to west and central European rivers. 相似文献
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Four Scythian kurgans of the burial site Beloe Lake-3 were studied in the Turan–Uyuk Depression in the Republic of Tyva. They were constructed about 2565–2390 calendar years ago (calibrated with deviation 1 σ). Soil formation after 2500 yrs of the construction of the kurgans was examined in the interkurgan area. The properties of the background surface and ancient buried soils have much in common, and the difference between the soils of the four kurgans is small. This attests to the fact that the paleoclimatic conditions in the period of the necropolis construction remained stable and were similar to the modern climatic conditions. According to palynological data, the climate at the stage of the construction of the first two kurgans was a little more humid in comparison with the modern climate; it became somewhat drier after 95 years, during the construction of the third kurgan (2425 cal. BP) and again tended to humidification at the final stage of the necropolis creation. These changes in the paleoclimatic conditions are indicated by variations in the structure and composition of associations of xerophytes, mesophytes, hydrophytes, and ruderal plants. At the Uyuk stage, the area was mainly occupied by steppe phytocenoses with a predominance of xerophytes over mesophytes, and hydrophilous vegetation was allocated to moistened habitats near water reservoirs. Larch forests grew near water bodies. The variable anthropogenic impact on the landscape was stronger at the initial and final stages of the construction of the Uyuk culture necropolis. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(9-10):2433-2442
Abstract An experiment was conducted to determine if time‐domain reflectometry (TDR) could be used to measure the water content at different depths in the O‐to‐75 cm soil layer. Probes of three wires (1/8 inch diameter and 30 cm exposed length) were installed in field plots differing in current crop‐fertilization history. Measurements of volumetric water content using bulk density and gravimetric water content were made to calibrate the TDR method. Comparison of water contents determined by TDR with those from gravimetric samples showed that there is a linear relationship (small offset but same slope) of water content with depth, indicating that there is little difference in volumetric water content from the 0 to 75 depth. However, the TDR method gives consistently lower water content values as compared with values obtained by gravimetric determination. Continuous measurements of profile soil water content with TDR in wet and dry periods during the year indicated that the mayor differences in volumetric water content correspond to the first 30 cm depth. 相似文献
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OBJECTIVE: Concordance of nutritional research priorities with the related burden of disease is essential to develop cost-effective interventions to address the nutritional problems of populations. The present study aimed to evaluate whether nutrition research priorities are in agreement with the population's nutritional problems in Latin America. DESIGN: The epidemiological profile was contrasted with the research priorities and research produced by academic institutions for each country. Qualitative analysis of research production by type of contribution to problem solving was also conducted. SETTINGS: Nine Latin American countries. RESULTS: Obesity (high body mass index (BMI)) and micronutrient deficiencies (anaemia) emerged as key problems, followed by stunting, breast-feeding/lactation and low birth weight. Wasting in children and women (low BMI) was uncommon. Concordance of ranked research priorities with the epidemiological profile of the country was generally good for nutrition-related chronic diseases, micronutrients and low birth weight, but not for undernutrition, stunting and breast-feeding. Studies on the efficacy and effectiveness of interventions were uncommon. CONCLUSIONS: The present research agenda insufficiently supports the goal of public health nutrition, which is to ensure the implementation of cost-effective nutrition programmes and policies. A more rational approach to define research priorities is needed. 相似文献
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Experimental studies and the analysis of published data have shown that carbon reserves in soils generally increase upon soil
exclusion from agricultural use. The rate of carbon accumulation in the abandoned soils depends on the soil type, the time
elapsed since the soil abandoning (the restoration period), and the thickness of the layer for which the rate of carbon accumulation
is determined. For the upper 20-cm-thick layer, it varies from 66 to 175 g C/m2 per year in dependence on the type of soil and averages 111 g C/m2 per year. The highest rate is typical of the first 10–15 years of soil restoration. According to our calculations, the carbon
sequestration in the upper 20-cm-thick layer of Russian soils due to changes in land use was 184–673 Mt C in 1990–2005 and
may reach 282–1030 Mt C by 2020. 相似文献
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Contamination levels of the organic horizon of Al–Fe-humus podzols (Albic Rustic Podzols) in the zone affected by atmospheric emissions of the Severonikel smelter (Murmansk oblast) within a 20-yearlong period are compared. The spatiotemporal changes in the total content of heavy metals in the soils in response to a decrease in aerotechnogenic loads have a complicated pattern. As the content of heavy metals in the soils varies widely, the correlation between their amount in the organic soil horizon and the distance from the contamination source is absent. In response to the ninefold decrease in the amount of atmospheric emission of Ni compounds, the bulk content of Ni in the organic horizons of podzols reliably decreased by 2.5 times. The threefold decrease in the emission of Cu compounds proved to be insufficient for a significant decrease in the Cu content in the soils. In 2016, the content of heavy metals in some sampling points even increased in comparison with the earlier periods. The Ni-to-Cu ratio in the soil samples changed significantly. In 1989–1994, bulk forms of heavy metals in the soil samples formed the sequence Ni > Cu > Co; in 2016, it changed to Cu > Ni > Co, which corresponds to the proportions of these metals in the aerial emissions. Under conditions of the continuous input of heavy metals from the atmosphere, the contamination of the organic horizons of podzols with heavy metals remains at the high or very high levels. 相似文献
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Concentration of sulfur (S) in mulberry leaves was 1.44 ～ 2.67 g kg?1 (Mean ± SE = 2.03 ± 0.30 g kg?1) in the six provinces of Jiangxi, Anhui, Hubai, Hunan, Jiangsu, and Fujian, China. Concentration of S in mulberry leaves was influenced significantly by the concentration of available S in soils of mulberry gardens (R 2 = 0.1773**, n = 52). Sulfur concentration in mulberry leaves, cocoon shells, silkworm pupae, and silkworm excrement in high-yielding mulberry gardens was higher than that in low-yielding mulberry gardens. The curvilinear correlation between concentration of sulfur in mulberry leaves and cocoon shells was significant (R 2 = 0.2101*, n = 26, a < 0). 相似文献
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Mao Ting Zhan Zhang Ni Shan-Jun Zhao Yi-Zhou Li Xin Zhang Li-Li Liu Yan Li Xu 《Genetic Resources and Crop Evolution》2021,68(5):1785-1797
Genetic Resources and Crop Evolution - Asian cultivated rice (Oryza sativa L.) is divided into two subspecies, indica (O. sativa L. subsp. indica) and japonica (O. sativa L. subsp. japonica).... 相似文献
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I. V. Ivanov O. S. Khokhlova V. V. Galitskii O. A. Chichagova E. P. Zazovskaya 《Eurasian Soil Science》2012,45(8):802-810
The dynamics of the 14C content in the humus of chernozems in 1900?C2008 are considered. The elevated 14C content in the atmosphere because of nuclear weapons tests has led to the contamination of humus with bomb radiocarbon. In 1966?C1968, the 14C reserves in the profiles of chernozems exceeded the background ones by 15%; in 1978, by 12%; and, in 1998, by 2%. By the year of 2008, its reserves became equal to the background ones. The 14C distribution along the soil profiles changed. By 1978, the 0- to 30-cm-thick soil layer became free from radiocarbon due to its self-purification; however, at depths of 40?C70 and 100?C115 cm, its weak accumulation was registered. By 2008, the whole soil profile was free from 14C. The main mechanism of the soil self-purification from radiocarbon is suggested to be the constant substitution of fragments of humus compound structures for those of fresh organic matter entering the soils with the 14C content being in equilibrium with the atmospheric one, i.e., due to the renewal of the carbon in the humus. The rate of the carbon renewal and its migration in the soils are assed based on the 14C concentrations in the humus. 相似文献