Zalewska Tamara, Biernacik Dawid
Institute of Meteorology and Water Management - National Research Institute, Waszyngtona 42, 81-1342 Gdynia, Poland.
Institute of Meteorology and Water Management - National Research Institute, Waszyngtona 42, 81-1342 Gdynia, Poland.
Sci Total Environ. 2022 Jun 20;826:154205. doi: 10.1016/j.scitotenv.2022.154205. Epub 2022 Feb 27.
The main aim of this research was to determine the transport and deposition velocities of Be and Pb based on a vast database containing the results of measurements of Be and Pb in fallout and aerosol samples carried out at several stations located throughout Poland in the period from 2000 to 2016. The monthly deposition flux of Be and Pb showed an unequivocal downward trend but was also subject to seasonal changes, with maximum values in the summer period. The same patterns were found in the case of the deposition rate, the average values of which were 0.7 cm s for Be and 0.5 cm s for Pb. A strong, statistically significant dependence of the deposition rate on the amount of dust was demonstrated, whereby a 10 μg m decrease in dust increases the Be deposition rate by 0.1 cm s. Reduction of the concentration of carrier particles reduces the share of dry deposition in favour of precipitation convection, which is much more significant for the transport of both isotopes to the surface. Study of the effect of meteorological parameters showed that the concentrations of Be in fallout and aerosol samples and Pb in fallout increase with increasing temperature, indicating a significant share of convection processes in isotope transport. The concentrations of Pb in aerosols did not show any significant statistical changes over time. Their maximum values were observed in the winter period, indicating an additional source of this isotope related to combustion processes in the heating season. The studies confirmed the dominant role of convective precipitation and large-scale precipitation processes in the elution of Be from the atmosphere by showing the monthly deposition of this isotope to be strongly dependent on the total precipitation (r = 0.618).
本研究的主要目的是基于一个庞大的数据库来确定铍（Be）和铅（Pb）的传输及沉降速度，该数据库包含了2000年至2016年期间在波兰各地多个站点对沉降物和气溶胶样本中铍和铅的测量结果。铍和铅的月沉降通量呈现出明确的下降趋势，但也存在季节性变化，夏季达到最大值。沉降速率也呈现相同模式，铍的沉降速率平均值为0.7厘米/秒，铅为0.5厘米/秒。研究表明沉降速率与沙尘量之间存在强烈的、具有统计学意义的相关性，沙尘量每减少10微克/立方米，铍的沉降速率就增加0.1厘米/秒。载体颗粒浓度的降低会减少干沉降的比例，有利于降水对流，这对于两种同位素向地表的传输更为重要。气象参数影响研究表明，沉降物和气溶胶样本中铍的浓度以及沉降物中铅的浓度随温度升高而增加，这表明对流过程在同位素传输中占很大比例。气溶胶中铅的浓度随时间未显示出任何显著的统计变化。其最大值出现在冬季，表明该同位素存在与供暖季节燃烧过程相关的额外来源。这些研究通过表明该同位素的月沉降量强烈依赖于总降水量（r = 0.618），证实了对流降水和大规模降水过程在大气中铍的洗脱过程中的主导作用。
