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911.
E. V. Tsvetnov O. B. Tsvetnova A. I. Shcheglov A. S. Ryabchuk 《Moscow University Soil Science Bulletin》2012,67(3):137-142
This paper is dedicated to the problem of radioactive contaminated lands?? assessment. We suggest the mechanisms of land value calculation under radionuclide contamination, accountability of such factors as internal and external human irradiation, migration of radionuclides in soil profile, and accountability of the own soil value in the totals sheet, as well as ecosystem services from the assessment facility. The approbation of the suggested method for the conditions of the Tula region is also presented. 相似文献
912.
Wang Lixia Yan Baixing Prasher Shiv O. Ou Yang Bian Yu Cui Hu 《Journal of Soils and Sediments》2019,19(12):4031-4041
Journal of Soils and Sediments - Hydrological condition is one of the important factors impacting microbial structure in riparian wetlands. However, how these microbial communities respond to... 相似文献
913.
Abigail E. Baxter Rory O. Maguire Garnett Whitehurst David Holshouser Mark Reiter 《Communications in Soil Science and Plant Analysis》2019,50(1):65-76
Soybean (Glycine max) commonly experience Mn deficiencies in the coarse-textured soils of Coastal Plain Virginia, especially under high pH conditions. The objective of this study was to investigate the ability of a novel coated fertilizer to provide Mn and B to soybeans in soils where Mn deficiency is common and B deficiency, although far less common than with Mn, is possible. A 60-d greenhouse experiment was conducted with three treatments: control, uncoated KCl, and Mn +B coated KCl applied to Bojac and Dragston sandy loams. Soil and whole plant tissue samples were collected throughout the experiment. Bojac and Dragston soils treated with the coated KCl contained 12.0 mg kg?1 and 15.8 mg kg?1 more Mehlich 1 – Mn, 21.7 mg kg?1 and 23.0 mg kg?1 more Mehlich 3 Mn, and 4.5 mg kg?1 and 4.6 mg kg?1 CaCl2 – Mn than the control and uncoated KCl, respectively. Coated KCl increased above ground tissue Mn by 42.9 mg kg?1 compared to the control and the uncoated KCl treatments in the Bojac soil, while the Dragston soil showed no significant differences in Mn tissue concentration between treatments. Above ground tissue, Mn was much lower in the Dragston soil than the Bojac, probably due to greater organic matter which chelates Mn keeping it less plant available. Boron concentrations did not differ in plant tissue or soil, regardless of the extraction method. Results indicate that the coated KCl product could consistently provide increased Mn concentration in acidic sandy soils despite varying levels of organic matter, but is not effective for B. 相似文献
914.
Enzyme-mediated solvent extraction of carotenoids from marigold flower (Tagetes erecta) 总被引:2,自引:0,他引:2
Barzana E Rubio D Santamaria RI Garcia-Correa O Garcia F Ridaura Sanz VE López-Munguía A 《Journal of agricultural and food chemistry》2002,50(16):4491-4496
Marigold flowers are the most important source of carotenoids for application in the food industry. However, the extraction gives almost 50% losses of the carotenoids depending on conditions for silaging, drying, and solvent extraction. In the past decades, macerating enzymes have been successfully applied to improve the extraction yield of valued compounds from natural products. In this work, an alternative extraction process for carotenoids is proposed, consisting of a simultaneous enzymatic treatment and solvent extraction. The proposed process employs milled fresh flowers directly as raw material, eliminating the inefficient silage and drying operations as well as the generation of hard to deal with aqueous effluents present in traditional processes. The process developed was tested at the 80 L scale, where under optimal conditions a carotenoid recovery yield of 97% was obtained. 相似文献
915.
The concentrations of Cu, Cd, Pb, Zn, V,Ni, Cr, Fe Ca, Mg and K were determined in the organicsoil layer (O horizon) of pine forests in Latvia. Theconcentrations were expressed on a mass, volume andsurface area basis. When concentrations were calculatedper unit mass of the O horizon, significant positivecorrelations between concentrations in the O horizon andPleurozium schreberi were achieved for mostelements (excepting Cr, Ca and K), and to lesser degreesfor Cu, Pb, Zn, V, Ni and Fe when calculated on a volumeor area basis. Non-rotated principal components analysisidentified a major soil factor related to bulk density(volume- and area-based concentrations). The main groupsof related elements defined by varimax-rotated PCAcomponents were similar for the mass- and volume-baseddata, and regions with elevated levels of these elementscould be related to local pollution sources, similar tothe patterns previously reported from surveys based onmoss. 相似文献
916.
Yu. N. Nikol’skii M. Castillo-Alvarez O. S. Bakhlaeva J. Gama-Castro C. Landeros-Sanchez 《Eurasian Soil Science》2010,43(9):985-992
The existing predictions of the changes in the yield of agricultural crops depending on the expected climatic scenarios for
the end of the 21st century are usually performed without consideration for the soil fertility alteration under the effect
of the climate changes. This work deals with an attempt to assess the effect of the possible changes of the fertility of agricultural
soils on the yield of corn and wheat under non- irrigation conditions with reference to the predicted scenario of climate
changes at the doubling of the CO2 in the atmosphere at the end of the 21st century. Studies were performed for typical regions of growing these crops in different
climatic zones of Mexico. 相似文献
917.
Differentiation of species from the Penicillium roqueforti group by volatile metabolite profiling 总被引:1,自引:0,他引:1
Species from the Penicillium roqueforti group were differentiated by volatile metabolite profiling primarily of sesquiterpenes. A total of 24 isolates from species P. roqueforti, Penicillium carneum, and the recently described species Penicillium paneum were inoculated on yeast extract sucrose agar. Volatile metabolites were collected by diffusive sampling onto tubes containing Tenax TA, overnight between the fifth and sixth days of incubation. Volatiles were thermally desorbed and analyzed by gas chromatography coupled to mass spectrometry. The sesquiterpene area of the chromatogram was investigated, and potential sesquiterpenes were tabulated by comparison of their Kovats retention index and mass spectrum. In general, P. carneum isolates produced the lowest number of sesquiterpenes, all of which were unique for P. carneum within the P. roqueforti group. P. roqueforti and P. paneum produced a larger variety of volatile metabolites, some of which they have in common and some of which are unique for the two species. (+)-Aristolochene was found in samples from P. paneum and P. roqueforti. Other Penicillium species in which (+)-aristolochene was also detected were P. commune, P. glandicola, and P. solitum. 相似文献
918.
Data on radiocarbon ages of different fractions of humus (humic acids, fulvic acids, and humin) in the profiles of chernozems
are analyzed. A chronoecological grouping of humus in modern and buried (fossil) soils is suggested. An increase in the radiocarbon
age of humic substances down the soil profile has a stepwise character. It is shown that the 14C content in chernozems decreases down the soil profile more somewhat slower than the 12C content. The dependence of a decrease in the humus content of buried soils on the age of burying is traced for a time span
of 800 ka. 相似文献
919.
A. O. Alekseev T. V. Alekseeva M. Hajnos Z. Sokolowska P. I. Kalinin A. V. Borisov 《Eurasian Soil Science》2008,41(13):1424-1432
This work presents the results of a study of changes in the soil mineral components and the related modifications of the chemical
composition and surface properties of soils in the desert-steppe zone in the southern part of the Ergeni Upland. Burial mounds
dating back to the Bronze epoch have been investigated. According to radiocarbon data, their ages are estimated at 5100 ±
50, 4410 ± 100, 4260 ± 120, 4120 ± 70, and 3960 ± 40 years. The substantial transformation of the clay minerals, the molar
chemical coefficients, the magnetic mineralogy, and the surface properties of the soils permits us to assess the rates of
the mineralogical transformations caused by the climate change during the time interval of less than <∼100 years. The ratio
between the content of the mineral phases in the buried soils of different ages testifies to the primary importance of climatic
factor in comparison with the total duration of weathering or the soil existence on the land surface prior to its burial,
i.e., the soil age. 相似文献
920.
E. D. Nikitin S. A. Shoba O. G. Nikitina E. P. Sabodina 《Moscow University Soil Science Bulletin》2008,63(2):92-96
The development of a concept of ecological functions of soils has facilitated interdisciplinary studies in various fields of soil science and neighboring sciences. As is shown in this paper, the ecological functions of activated sludge have a lot of features similar to the ecological functions of natural soils. A classification of the major ecological functions of activated sludge is suggested. It is stressed that the role of activated sludge as a protective barrier is particularly important for the biosphere preservation, as the self-purification capacity of many water objects is almost exhausted. In general, activated sludge can be considered a biological reactor of a polyfunctional character. 相似文献