基于未扰动土壤中7Be的量估算其沉降通量的研究

本文基于未扰动土壤中⁷Be的量和日降雨资料，估算了陕西省杨凌区天然放射性核素⁷Be的沉降通量。结果显示，雨水中⁷Be的实测浓度和估算浓度之间无显著差异(P>0.05)，说明基于未扰动土壤中⁷Be的量估算雨水中⁷Be的浓度，进而估算⁷Be的沉降通量是合理的。计算发现，⁷Be沉降通量年内和年际均存在较大变异性，月沉降通量变异系数达0.97，夏季沉降通量大，冬季的小，年均沉降通量为2069 Bq/m²。未扰动土壤中⁷Be的量及⁷Be的沉降通量主要受降雨量及其时间分布的影响，不同时间尺度下⁷Be沉降通量与相对应降雨量之间呈显著线性正相关。

7Be Atmospheric Deposition Flux Determined From Undisturbed Soil

Based on ⁷Be inventories in undisturbed soil and daily rainfall data, ⁷Be deposition flux was estimated in Yangling District, Shaanxi Province, China. The results show that there is no significant difference between the measured ⁷Be mean concentration and the estimated in rainfall, which demonstrates that it is reasonable to use ⁷Be inventories in undisturbed soil to estimate ⁷Be mean concentration in rainfall and then calculate ⁷Be deposition flux. Inter and intra-annual variation of ⁷Be deposition flux is significant difference at the study site. The coefficient of variation for monthly ⁷Be deposition flux is 0.97. There is a marked seasonality in the seasonal values of ⁷Be deposition flux. Maximum value occurs in summer and minimum value occurs in winter. The annual ⁷Be deposition flux is 2069 Bq/m². The variation of ⁷Be inventory in undisturbed soil and ⁷Be deposition flux were determined by the precipitation amount and its temporal distribution. The strong linear correlation between ⁷Be deposition flux and precipitation amount is evident at different time scales.