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131.
The aim of the study was to compare accumulation efficiency of Al, Ba and nutritional elements (Ca, Fe, K, Mg, Mn, Na) exhibited by six edible mushrooms collected in particular regions of Poland during the last 20 years. The studied mushroom species were Boletus edulis, Cantharellus cibarius, Lactarius deliciosus, Leccinum aurantiacum, Suillus luteus and Xerocomus badius. The highest and the lowest concentrations of the elements in tested mushroom species were 11 – 410, 34 – 337, 16785 – 34600, 140 – 607, 12 – 75 and 16 – 143 mg kg?1d.m., respectively. The highest average concentrations of Al, Mg and Mn were observed in Suillus luteus fruiting bodies, while for Ba, Ca, K and Na it was in Lactarius deliciosus. BCF >1 was found for K and Mg in all tested mushroom species and additionally for the highest Ca and Na concentrations of all tested mushroom species except for C. cibarius and S. luteus, respectively. For the other tested elements (Al, Ba, Fe and Mn) BCF values < 1 were recorded.  相似文献   
132.
Mitigation and Adaptation Strategies for Global Change - The focus of this perspective piece is on memory, persistence, and explainable outreach of forced systems, with greenhouse gas (GHG)...  相似文献   
133.
134.
The chemical structure of liquid products of the pinewood sawdust (W) co-pyrolysis with polystyrene (PS) and polypropylene (PP) with and without the zinc chloride as an additive was investigated. The pyrolysis process was carried out at 450 °C with the heating rate of 5 °C/min. The yield of liquid products of pyrolysis was in the range of 37–91 wt% and their form was liquid or semi-solid depending on the composition of the wood/polymer blend. The zinc chloride addition to wood/polymer blends has influenced the range of samples decomposition as well as the chemical structure of resulted bio-oils. All bio-oils from wood/polypropylene blends were two-phase (liquid and solid). Contrarily, all bio-oils obtained from biopolymer/polypropylene blends with zinc chloride added were yellow liquids. All analyses proved that the structure and the quality of bio-oil strongly depend on both the composition of the blend and the presence of ZnCl2 as an additive. The FT-IR analyses of oils showed that oxygen-containing groups and hydrocarbons content highly depend on the composition of biomass/synthetic polymer mixture. The fractionation of bio-oils by column chromatography with four different solvents was followed by GC–MS analysis. Results confirmed the significant removal and/or transformation of oxygen-containing organic compounds due to the zinc chloride presence during pyrolysis process.  相似文献   
135.
The aim of the study was to estimate Zn phytoextraction and changes in biomass of S?×?rubens growing in modified Knop's solution with different levels of Zn addition (0.5, 1.0, 2.5 and 5.0?mM). Obtained results were correlated with secretion of selected low-molecular-weight organic acids (LMWOAs) in the rhizosphere, roots and leaves. An increase in Zn concentration in Knop's solution resulted in Zn accumulation in roots, shoots and leaves. The highest accumulation was observed for plants growing in 5?mM Zn, at concentration levels 4741.36?±?98.66, 1227.31?±?16.57 and 2241.65?±?34.90?mg?kg?1 DW in roots, shoots and leaves, respectively. The bioaccumulation factor and the translocation factor for plants growing in 0.5, 1.0 and 2.5?mM Zn clearly indicate that this Salix taxon is an effective Zn accumulator. The general reduction of Salix biomass with an increase in Zn concentration in the solution was observed. In the rhizosphere, the total LMWOA concentration was almost 0.93?µmol?kg?1 DM for control (Zn free) plants, while for 5.0?mM of Zn it was 4.9?µmol?kg?1 DM. Increasing concentrations of acids were observed in roots (1.34 for the control and 5.57?µmol?kg?1 DM for plants treated with 2.5?mM of Zn).  相似文献   
136.
Two-year old Ulmus laevis Pall (U. laevis) seedlings were cultivated in a three-month hydroponic experiment with inorganic (aresenite – As(III) and arsenate – As(V)) and organic (dimethylarsenic acid – DMA(V)) arsenic forms, at 0.06 and/or 0.6?mM concentrations. Further, the profile and content of total low molecular weight organic acids (LMWOAs) were investigated in the rhizosphere, roots and leaves of U. laevis. Obtained results showed that the addition of As(III) or As(V) individually or in a mixture led to increased LMWOAs concentration in the rhizosphere, especially of oxalic and malonic acids, in comparison to the control, while in roots the overall content of the profiled LMWOAs decreased. In both rhizosphere and roots, addition of the DMA(V) form resulted in the inhibition of LMWOAs exudation into the rhizosphere and their creation in plant roots. Leaves were characterised by a higher content of LMWOAs than in the rhizosphere and roots for all experimental systems, where the profile and content of LMWOAs was strictly correlated with the analysed As forms. Our study indicated that creation of LMWOAs in U. laevis organs and their exudation to the rhizosphere could be responsible for the As toxicity tolerance of the plants.  相似文献   
137.
Environmental Geochemistry and Health - The authors present the results of chemical and mineralogical analyses of urban dusts collected in the spring seasons of 2015 and 2016 in three different...  相似文献   
138.
Redistribution of soil, nutrients, and contaminants is often driven by wind erosion in semiarid shrublands. Wind erosion depends on wind velocity (particularly during episodic, high-velocity winds) and on vegetation, which is generally sparse and spatially heterogeneous in semiarid ecosystems. Further, the vegetation cover can be rapidly and greatly altered due to disturbances, particularly fire. Few studies, however, have evaluated key temporal and spatial components of wind erosion with respect to (i) erosion rates on the scale of weeks as a function of episodic high-velocity winds, (ii) rates at unburned and burned sites, and (iii) within-site spatial heterogeneity in erosion. Measuring wind erosion in unburned and recently burned Chihuahuan desert shrubland, we found (i) weekly wind erosion was related more to daily peak wind velocities than to daily average velocities as consistent with our findings of a threshold wind velocity at approximately 7 m s(-1); (ii) greater erodibility in burned vs. unburned shrubland as indicated by erosion thresholds, aerodynamic roughness, and nearground soil movement; and (iii) burned shrubland lost soil from intercanopy and especially canopy patches in contrast to unburned shrubland, where soil accumulated in canopy patches. Our results are among the first to quantify post-fire wind erosion and highlight the importance of accounting for finer temporal and spatial variation in shrubland wind erosion. This finer-scale variation relates to semiarid land degradation, and is particularly relevant for predictions of contaminant resuspension and redistribution, both of which historically ignore finer-scale temporal and spatial variation in wind erosion.  相似文献   
139.
Whether anti-vibration gloves are effective in protecting against vibrations depends not only on the materials they are made of, but also on the parameters of the source of vibration. Depending on those parameters, the effectiveness of the same means of protection may be radically different. This article presents a methodology of using a neural network to test anti-vibration gloves. A network can map gloves in various conditions, i.e., for vibrations of various amplitudes and spectra, and for various forces exerted by the worker on a tool. Real, measured vibration signals produced by different tools were used in training a neural network. The results presented in this article prove that real properties of gloves are accurately represented by their models developed as a result of training a neural network.  相似文献   
140.
Polyacrylamide(PAM) used in sludge dewatering exists widely in high-solid anaerobic digestion. Acrylamide is registered in the list of chemicals demonstrating toxic, carcinogenic and mutagenic properties. Therefore, it is reasonable to ask about the mobility of such residual substances in the environment. The study was carried out to assess the impact of the mesophilic(39 ± 1°C) and thermophilic(54 ± 1°C) fermentation process on the level of acrylamide monomer(AMD) content in the dairy sludge. The material was analysed using high-performance liquid chromatography(HPLC) for quantification of AMD. The results indicate that the process of methane fermentation continues regardless of the temperature effects on the degradation of AMD in dairy sludge. The degree of reduction of acrylamide monomer for thermophilic fermentation is 100%, while for mesophilic fermentation it is91%. In practice, this means that biogas technology eliminates the risk of AMD migration to plant tissue. Moreover, it should be stressed that 90% of cumulative biogas and methane production was reached one week earlier under thermophilic conditions — the dynamics of the methanisation process were over 20% faster.  相似文献   
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