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Journal of Soils and Sediments - Urbanization significantly changes the carbon balance of the terrestrial ecosystem, an important component of which is soil CO2 emission. One of the main sources of...  相似文献   
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Twenty plots (20 m2 each) were selected in coniferous and mixed forests of the industrial Vologda district and the Vytegra district without developed industries in Vologda region. In March, snow cores corresponding to the snow cover depth were taken on these plots. In August, soil samples from the 0- to 20-cm layer of litter-free soddy-podzolic soil (Albic Retisol (Ochric)) were taken on the same plots in August. The content of mineral nitrogen (Nmin), including its ammonium (NH+4) and nitrate (NO-3) forms, was determined in the snow (meltwater) and soil. The contents of total organic carbon, total nitrogen, and elements (Al, Ca); pH; particle size distribution; and microbiological parameters―carbon of microbial biomass (Cmic) and microbial respiration (MR)―were determined in the soil. The ratio MR/Cmic = qCO2 (specific respiration of microbial biomass, or soil microbial metabolic quotient) was calculated. The content of Nmic in meltwater of two districts was 1.7 mg/L on the average (1.5 and 0.3 mg/L for the NH+4 and NO3 forms, respectively). The annual atmospheric deposition was 0.6–8.9 kg Nmin/ha, the value of which in the Vologda district was higher than in the Vytegra district by 40%. Reliable correlations were found between atmospheric NH+4 depositions and Cmic (–0.45), between NH+4 and qCO2 (0.56), between atmospheric NO-3 depositions and the soil NO-3 (–0.45), and between NO-3 and qCO2 (–0.58). The content of atmospheric Nmin depositions correlated with the ratios C/N (–0.46) and Al/Ca (–0.52) in the soil. In forests with the high input of atmospheric nitrogen (>2.0 kg NH+4/(ha yr) and >6.4 kg Nmin/(ha yr)), a tendency of decreasing Cmic, C/N, and Al/Ca, as well as increasing qCO2, was revealed, which could be indicative of deterioration in the functioning of microbial community and the chemical properties of the soil.  相似文献   
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Eurasian Soil Science - The relationships between the soil CO2 emission and microbial properties have been studied in Haplic Chernozem of steppe, forest (oak), bare fallow of the reserve area and...  相似文献   
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The change in the composition of camel milk in four dromedaries was studied by including the common measured parameters: protein, total fat, lactose, main minerals (calcium, phosphorus, and iron), and vitamin C. The fat matter varied from 4.34% to 7.81% with a slight decrease all along the lactation and a minimal value at the 14th week corresponding to the lactation peak. Those variations were less important for protein content (from 2.58% to 3.64%), but the minimal value was observed at the 14th week also. The lactose varied slightly around its mean of 3.46%. The vitamin C concentration varied from 48 to 256 mg/l with a tendency of increasing all along the lactation. Calcium and phosphorus concentrations were quite parallel and their ratio Ca/P was constant. The minimal values (1.43 g/l for calcium and 1.16 g/l for phosphorus) were observed at the beginning of the lactation. The iron concentrations varied around the mean of 1.73 mg/l.  相似文献   
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In the forest, meadow, arable, and urban ecosystems (recreational, residential, and industrial zones) of Sergiev Posad, Shatura, Serpukhov, and Serebryanye Prudy districts of Moscow region, spatially separated sites (3–5 points per site) have been randomly selected and soil samples have been taken from the 0–10 (plant litter excluded) and 10- to 150-cm layers (a total of 201 samples have been taken). In the samples, the microbial biomass carbon (Cmic), the rate of the basal (microbial) respiration (BR), and the physical parameters (the particle size distribution (PSD), organic carbon (Corg), pH, heavy metals, and nutrients (NPK)) have been determined. High spatial variability has been revealed for Cmic and BR in all the ecosystems and the functional zones of the studied districts, and a clear tendency of a decrease in these parameters has been shown in the arable soils (by 1.4–3.2 times) and the industrial zone (by 1.7–3.3 times) compared to the natural analogues and other corresponding functional zones. It has been shown that the spatial distribution of the microbiological parameters is significantly (p ≤ 0.05) affected by the physicochemical properties of the soil (Cmic by the PSD and PSD × Corg; BR by the pH and pH × NPK; contributions of 40 and 63%, respectively), as well as by the type of ecosystem and the region of study (the contribution of the sum of these factors to the Cmic and BR was 56 and 67%, respectively). A tendency toward the deterioration of the functioning of the microbial community under the anthropogenic transformation of the soil has been shown. The contribution of the urban soils as a potential source of CO2 emission to the atmosphere has been calculated and discussed.  相似文献   
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Journal of Soils and Sediments - The research aimed to investigate properties and functions of soils constructed from alkaline mining wastes of different origin to remediate the industrial barren...  相似文献   
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Eleven samples of dromedary camel colostrum in Kazakhstan, which originated from one farm only, were collected to study the changes in the physico-chemical composition (total fat, total protein, iodine index, lactose, calcium, phosphorus, iron, vitamin C, urea, ammonia, density, Dornic acidity, pH, and skimmed dry matter) all along the first postpartum week. At that time, the fat matter decreased from 25.9% to 3.1% and protein from 17.2% to 4.2%, in contrast to vitamin C which increased. Minerals showed high variations with lower values the first day after parturition and variable changes up to the end of the week where the values were stabilized. The iron concentration decreased from the second day postpartum. No clear changes of the other parameters were observed, notably for the non-protein nitrogen (urea and ammonia).  相似文献   
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