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《Communications in Soil Science and Plant Analysis》2012,43(15-20):2899-2909
Abstract Long‐term field experiments are the most suitable tools for determining the optimal nutrient‐supplying technologies that contribute to sustainable agriculture. Under certain environmental conditions (low precipitation, deep groundwater table, negative water balance), part of the applied nitrogen (N) can be found in the soil profile for a longer period and provide N nutrition for crops. A long‐term field experiment has been running at Nagyhörcsök in Hungary since 1973. The nitrogen–phosphorus–potassium (NPK) application rates follow the overall nutrient‐supplying categories (weak, medium, adequate, excessive) by the main nutrients and their combinations. The seasonal dynamics of exchangeable NH4 and NO3 were followed in 1983 and 2003. From certain treatments, two parallel average samples (20–20 subsamples were mixed to get average composite samples by plots) were collected 19 times from March through November from three soil layers. There was no difference in NH4‐N between years, and its seasonal fluctuation was slight in both years, whereas there was an increase in NO3‐N in accordance with the applied N rates. No significant difference occurred in the NO3‐N of the N0P0K0 and the N1P1K1 treatments during both years. A significantly higher NO3‐N content was observed in the higher rate nutrient treatments. Both soil N forms were higher in 1983 than in 2003. Based on the experimental results, the fate and behavior of the surplus N in the soil can be characterized and the residual amount can be taken into account during the calculation of the N‐fertilization demand of arable crops in relation to the N‐fertilizer advisory system. 相似文献
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Land use and soil cover patterns of arable lands in Balakhna district of Nizhny Novgorod gubernia in the last quarter of the 18th century and in the middle of the 19th century were studied with the use of the General Land Survey plan of Balakhna district (scale 1 : 84000), the map of Nizhny Novgorod gubernia by Mende (scale 1 : 42000), and the State Soil Map (scale 1 : 1 M). The data obtained attested to a steady and considerable decrease in the plowed area during that period. According to the historical materials, at the end of the 18th century, plowland occupied about 1290 km2, or 32% of the entire district (4200 km2). In the middle of the 19th century, the plowed area decreased to about 990 km2 (25%). According to the modern statistical data on land use in Balakhna district (within its boundaries of the 18th–19th centuries), the area of plowed fields is less than 700 km2 (18%). This means that at least 14% of the study area is occupied by the postagrogenic soils. If we take the plowed area of the district in the 18th century for 100%, we can conclude that more than 40% of formerly plowed lands have been transformed into long-term fallows. The absolute predomination of soddy-podzolic soils (Retisols) is typical of the soil cover of Balakhna district. In the course of the reduction of the plowland area from the end of the 18th century to the middle of the 19th century, the percent of different soils composing this area did not change much. In general, the impact of soil quality on the decrease in the plowland area in that period is not observed. 相似文献
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Inmaculada Riba Enrique García-Luque Alejandra Maz-Courrau María Luisa González de Canales Tomás Ángel DelValls 《Water, air, and soil pollution》2010,212(1-4):329-336
This study assesses the effect of salinity in bioavailability and toxicity of Zn by means of laboratory bioassays by observing contamination in both sediment and water, accumulation of Zn in biological tissues, and histopathological damage in the gills and guts tissues of Ruditapes philippinarum clams, which were exposed to different types of sediments from the Gulf of Cádiz (SW Spain) as well as two dilutions of toxic mud coming from an accidental mining spill. With this objective, the coefficients of distribution (K D) for Zn between overlying water and sediments were calculated, the histopathological frequencies in the tissues of the gills and guts of clams were determined, and the biota-sediment bioaccumulation factors as well as the bioaccumulation factors were quantified in the different stations. Results showed that the greatest histopathological damages appeared when the salinity values decreased. Statistical results showed that salinity was inversely correlated with histopathological damage (p?<?0.01) for the lesion index for gills. The most outstanding results were observed in the two dilutions of toxic mud (0.3% and 7.9%) at a salinity value of 10. Salinity was inversely correlated with the concentration of Zn in biological tissues (p?<?0.05) and inversely correlated with the concentration of Zn in water and sediment. Zn mobilization to the overlying water is produced when salinity values decrease. 相似文献
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Scientific cooking, which offered reliable results from standardized recipes, required exact measuring. The cup measure was a portion of an old official ale measure, but the teaspoon and tablespoon evolved from common cooking and eating utensils. Several versions of equivalents developed and were in use by the late 19th century. In 1915 the U.S. Bureau of Standards officially codified the amounts, but, as late as 1948, measuring utensils available for purchase were not necessarily accurate. 相似文献
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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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Ovsepyan L. A. Kurganova I. N. Lopes de Gerenyu V. O. Rusakov A. V. Kuzyakov Ya. V. 《Eurasian Soil Science》2020,53(1):50-61
Eurasian Soil Science - The postagrogenic dynamics of organic carbon (Corg), total nitrogen (Ntot), and density fractions of organic matter (OM) in the dark gray soil (Haplic Phaeozem, Belgorod... 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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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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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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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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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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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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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