Soil moisture and precipitation are important parameters that influence Hg air-surface exchange at background sites, thereby influencing Hg distribution in the environment. Australia is a unique and understudied climatic region. Rainfall across the temperate regions of Australia is highly variable on both annual and inter-annual scales and is overall a relatively dry continent. As such, it is plausible that Australian terrestrial fluxes do not respond to precipitation and soil moisture changes in the same way as observed in the Northern Hemisphere. This study focused on investigating Hg flux in response to precipitation and soil moisture changes at a background site in south-eastern Australia over a 14-month measurement period. The Austral summer experienced the highest rainfall, with a cumulative average of 3.21 mm d⁻¹ and rainfall occurring during 5.95% of the half-hourly measurements during this period. Autumn 2018 had the lowest daily rainfall (1.20 mm d⁻¹). Hg fluxes during rainfall averaged 1.03 ng m⁻² h⁻¹ (standard deviation (SD), 20.78), compared to the overall study average of 0.002 ng m⁻² h⁻¹ (SD 14.23), signifying influence from the occurrence of rain. Mercury fluxes at this site show substantial spikes that often coincided with the occurrence of rainfall. Mercury released from the substrate during rainfall is primarily due to the interstitial release of Hg as the water infiltrates the soil pore space. Deposition during rainfall also indicated rapid recycling of Hg between the soil and air. There was little evidence of enhanced Hg fluxes occurring caused by increased soil volumetric water content. Lack of enhancement suggests that Hg stores within the substrate are depleted during the initial release.

土壤水分和降水是影响背景地点汞空气表面交换的重要参数，从而影响环境中汞的分布。澳大利亚是一个独特而未被充分研究的气候区域。澳大利亚温带地区的降雨量在年度和年度间变化很大，总体而言是一个相对干燥的大陆。因此，有可能澳大利亚陆地通量对降水和土壤水分变化的响应方式与在北半球所观察到的方式不同。这项研究的重点是调查在14个月的测量期内澳大利亚东南部某背景站点响应于降水和土壤水分变化而产生的汞通量。澳大利亚夏季的降雨量最大，累计平均为3.21 mm d ^-1在此期间，每半小时测量值的5.95％发生降雨。2018年秋季的日降雨量最低（1.20 mm d ^-1）。降雨期间的汞通量平均为1.03 ng m ^-2 h ^-1（标准偏差（SD）为20.78），而总体研究平均值为0.002 ng m ^-2 h ^-1（SD 14.23），表示受到降雨的影响。该地点的汞通量显示出大量的峰值，通常与降雨的发生同时发生。降雨过程中从基质释放的汞主要是由于水渗透到土壤孔隙空间后，汞的间隙释放。降雨期间的沉积也表明汞在土壤和空气之间快速循环。几乎没有证据表明由于土壤体积含水量增加而导致汞通量增加。缺乏增强表明底物内的汞存储在初始释放过程中被耗尽。