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971.
The seed storage protein composition of one collection of cultivated einkorn wheat (Triticum monococcum L. ssp. monococcum) of Spanish origin has been analysed by SDS-PAGE and A-PAGE. Three allelic variants were detected for the Glu-A1m, whereas up to six alleles were detected for the Glu-A3m. For the gliadins, 7 and 14 alleles for the Gli-A1m and Gli-A2m were found between the evaluated accessions. Internal variability was detected in some of these materials, which could be
related to the landrace nature of them. Up to 48 different genotypes based on the origin and seed storage protein composition
have been identified. Further researches on these materials must be carried out for determining the variability degree in
morphological traits that could complement the evaluation for their safeguard. 相似文献
972.
P.K. Farage J. Ard L. Olsson E.A. Rienzi A.S. Ball J.N. Pretty 《Soil & Tillage Research》2007,94(2):457-472
Historically, agriculturally induced CO2 release from soils has contributed to rising levels in the atmosphere. However, by using appropriate management, soils can be turned into carbon sinks. Many of the dryland regions of the world are characterised by degraded soils, a high incidence of poverty and a low capacity to invest in agriculture. Two well-proven soil organic matter models (CENTURY 4.0 and RothC-26 3) were used two explore the effects of modifying agricultural practices to increase soil carbon stocks. The changes to land management were chosen to avoid any significant increase in energy input whilst using technologies that would be available without radically altering the current agricultural methodology. Case studies were selected from dryland farming systems in Nigeria, Sudan and Argentina. Modelling showed that it would be possible to make alterations within the structure of the current farming systems to convert these soils from carbon sources to net sinks. Annual rates of carbon sequestration in the range 0.08–0.17 Mg ha−1 year−1 averaged over the next 50 years could be obtained. The most effective practices were those that maximised the input of organic matter, particularly farmyard manure (up to 0.09 Mg ha−1 year−1), maintaining trees (up to 0.15 Mg ha−1 year−1) and adopting zero tillage (up to 0.04 Mg ha−1 year−1). Verification of these predictions will require experimental data collected from field studies. 相似文献
973.
Slobodan Miko Georg Koch Saša Mesić Martina Šparica Miko Marko Šparica Polona Vreča Tadej Dolenec 《Journal of Soils and Sediments》2007,7(5):303-312
Background, Aim and Scope
Most of the cathment areas supplying water and mineral matter to the Adriatic bays with healing mud/peloids are affected by various degrees of human impact, i.e. activity that is introducing various types of contaminants to environment. The bays represent shallow marine depositional environments where organic-rich sediments accumulate. Investigations for balneological characterization of several localities along the Croatian coast have shown that these organic-rich sediments may be classified as healing mud, i.e. peloids. Healing mud due to its balneologic features is in treatment of various diseases and in improvement of the overall health conditions and general well-being. Various components of mud, particularly trace elements, could be absorbed through dermal contact. Therefore, the study of the abundance of such potentially toxic elements as As, Pb, Hg, Cd, Se, Sb, Cu, Zn in marine sediments used as healing mud is necessary in order to know their mobility and to avoid possible intoxications. 相似文献974.
Gómez-Plaza E Gil-Muñoz R López-Roca JM Martínez A 《Journal of agricultural and food chemistry》2000,48(3):736-741
The purpose of this work was to determine the influence of vinification technique (maceration temperature and clarification method), storage temperature, and length of storage time on the phenolic compounds and color of young red wines. Multivariate analysis of variance and principal component analysis pointed to significant differences among all of the variables according to vinification technique and length of storage time. Storage temperature did not cause significant differences between some of the variables. The best color characteristics were obtained when low-temperature maceration wines were clarified with polyvinylpyrrolidone. Color quality also improved with lower storage temperature. 相似文献
975.
Robson Thiago Xavier de Sousa Gaspar Henrique Korndörfer Rogério Augusto Brem Soares Patrícia Rezende Fontoura 《Journal of plant nutrition》2015,38(9):1444-1455
Phosphate applications are still rare in sugarcane cultivation and can be done with phosphorus fertilizers of residual over. This study aims to evaluate the agronomic efficiency of phosphate fertilization before sugarcane planting and its effect on sugarcane yield. The study was carried out over three crop cycles at the Jalles Machado sugar-mill in Goianésia, GO, Brazil. The treatments consisted of five different phosphorus sources (soluble and insoluble) applied at a rate of 300 kg ha?1 phosphorus pentoxide (P2O5). The phosphorus fertilizers used were: triple superphosphate, mono-ammonium phosphate (MAP), Arad rock phosphate, Itafós rock phosphate, and magnesium term phosphate. The effects of these fertilizers were evaluated by plant height (ground to Top Visible Dewlap; TVD), leaf phosphorus content, agronomic efficiency, and sugarcane yield from cane-plants, first ratoon, and second ratoon. Magnesium term phosphate and triple superphosphate resulted in greater plant-cane height. Leaf phosphorus concentrations were highest with applications of MAP, magnesium term phosphate, and triple superphosphate. Phosphate applications did not affect sugarcane plant yield, but did increase ratoon yield. In general, the residual effect of insoluble phosphate increased over the years. The agronomic efficiency (AE) of phosphate was (in descending order): triple superphosphate (100%), term phosphate (89%), MAP (80%), Itafós rock phosphate (67%), and Arad rock phosphate (60%). 相似文献
976.
María López-Martín Marta Velasco-Molina Heike Knicker 《Journal of Soils and Sediments》2016,16(2):360-370
Purpose
Fire in mountainous areas can lead to increased variability of their soil organic matter (SOM) due to spatial inhomogeneity and pre-fire fuel distribution. Here, we elucidated if this was the case in our study area and how this affected the reliability of solid-state 13C NMR spectroscopy applied for the study of the medium-term impact of fire on SOMMaterials and methods
The study occurred in the Sierra de Aznalcóllar, Southern Spain, which experienced their last intense fire 7 years before sampling. In a first approach (method 1), the corners and the center of a randomly chosen square with a side length of 15 m were sampled and analyzed separately. For comparison, composite samples (method 2) were obtained from three soils. We characterized material from unburnt, burnt, and double burnt regions. Data describing the physical and chemical properties of the soils together with the NMR spectroscopic characterization were analyzed using ANOVA.Results and discussion
Both sampling methods yielded comparable results with comparable standard errors. No major differences between the fire-affected and unburnt soils were observed with respect to physical and chemical properties and C and N contents, but solid-state 13C NMR spectroscopy indicated a small but significant elevation of aromaticity in the soils with fire history.Conclusions
The analysis showed that sampling with reduced replicates (method 1) can still lead to representative NMR data. The more complex sampling of comparing three composite samples (method 2) did not decrease the standard error. Our results also indicate that in the study area typical properties of the soil and its SOM induced by former burnings will not persist beyond a few decades.977.
Martyna A. Rzętała 《Journal of Soils and Sediments》2016,16(10):2458-2470
Purpose
Cadmium (Cd) is considered a toxic element and its concentrations are relevant to human health and the environment. Therefore, the purpose of the study was to determine the extent to which the bottom sediments of water bodies (artificial lakes and ponds) in the Silesian Upland in southern Poland are contaminated with Cd; an attempt was also made to determine the factors that condition spatial differences in the concentration of this element between individual water bodies in the region.Materials and methods
Measurements of the Cd content in bottom sediments were carried out in 35 water bodies in southern Poland in 2011 and 2012. Depending on the surface area and morphometric characteristics, from two to nine samples representative in terms of sediment thickness were collected in each water body. Cadmium concentrations were determined for 92 0.25 g aliquots using the TD-ICP method.Results and discussion
Cadmium content in all samples (0.7–580.0 mg kg?1) was higher than the natural range of concentrations for this element in the Earth’s crust (0.1–0.3 mg kg?1) and the geochemical background for Poland (0.5 mg kg?1) and, with a few exceptions, was also higher than the preindustrial concentration (1.0 mg kg?1) and the regional geochemical background (2.5 mg kg?1). Adopting natural Cd concentrations in the Earth’s crust (0.1–0.3 mg kg?1) as the baseline for the geoaccumulation index (Igeo), the sediments examined can be classified as extremely and heavily contaminated (and moderately contaminated in a small number of cases). The assessment of sediment quality based on Igeo, with the regional geochemical background (2.5 mg kg?1) adopted as the baseline, results in non-contaminated and moderately contaminated sediments being dominant with a far smaller number of heavily and extremely contaminated ones.Conclusions
In the case of several water bodies, Cd concentrations were at record levels that have not been found anywhere else in the world. On the basis of the Igeo, sediments of varying quality were found—from virtually uncontaminated to extremely contaminated. The Igeo index as an indicator of the quality of bottom sediments is a measure that requires careful interpretation, especially when different concentration levels regarded as natural are used for determining its value.978.
This article describes the temperature dependence of sixteen PCBs in ambient air from the relationship ln(C) = m + (1000/T) + b and the Clausius-Clapeyron equation from data obtained at an open urban area of Madrid. The study was applied to predice long/short range transport influence as PCB sources in a typical semi-urban ambient without the influence of industrialised or contaminated sites around. The present study also relate surface soil/ambient air data to characterise soil/air cycled seasonal behaviour in the observation site. Regarding both compartments, a comparison was done calculating fugacity quotients from one full year data. 相似文献
979.
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
980.
Forms of cadmium occurrence in the bottom sediment of a heated water reservoir, polluted substantially with this metal was analysed in the paper. Apart from the analysis mentioned above, a total cadmium content in the bottom sediment and a content of cadmium dissolved in the water of the reservoir was also determined. Dependences between particular forms of cadmium occurrence and its total content in the bottom sediment were analysed. An influence of cadmium content in water on the level of particular cadmium forms in the bottom sediment and an influence of other parameters of the reservoir's water on the content of cadmium in the bottom sediment were also examined. 相似文献