Mercury in terrestrial forested systems with highly elevated mercury deposition in southwestern China: The risk to insects and potential release from wildfires
Mercury in terrestrial forested systems with highly elevated mercury deposition in southwestern China: The risk to insects and potential release from wildfires
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中国西南部汞沉积高度升高的陆地森林系统中的汞：对昆虫的风险和野火的潜在释放
DOI：
10.1016/j.envpol.2016.01.003
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发表时间：
2016
影响因子：
8.9
通讯作者：
Zhang Xiaoshan
中科院分区：
文献类型：
--
作者：
Zhou Jun;Wang Zhangwei;Sun Ting;Zhang Huan;Zhang Xiaoshan
森林被认为是全球汞循环中的一个汞库。然而，很少有研究调查汞在中国森林系统中的分布。中国西南部铁山坪森林集水区受到工业活动和燃煤汞排放的影响。我们的工作研究了大气、土壤、植被和昆虫中的汞含量，以期估计森林火灾期间汞释放的可能性。本研究的结果表明，总气态汞（TGM）浓度高度升高，年平均浓度为3.51 ± 1.39 ng m−2。在植物组织中，汞含量的大小顺序为叶/针>根>树皮>分支>树干。生态系统汞库总量为103.5 mg m− 2，约99.4%的汞存在于土壤层（0-40 cm）中。其余0.6%（0.50 mg m−2）的汞储存在生物质中。森林生态系统中大量的汞库存对大气汞构成严重威胁，在潜在的野火和森林昆虫（金龟子、天牛和天牛）的额外生态压力下，汞浓度分别为1983 ± 446、49 ± 38和7 ± 5 ng g−1。因此，本研究中获得的结果对森林中汞储存、森林昆虫风险和野火期间汞向大气释放的可能性的全球估计具有影响。
Forests are considered a pool of mercury in the global mercury cycle. However, few studies have investigated the distribution of mercury in the forested systems in China. Tieshanping forest catchment in southwest China was impacted by mercury emissions from industrial activities and coal combustions. Our work studied mercury content in atmosphere, soil, vegetation and insect with a view to estimating the potential for mercury release during forest fires. Results of the present study showed that total gaseous mercury (TGM) was highly elevated and the annual mean concentration was 3.51 ± 1.39 ng m−2. Of the vegetation tissues, the mercury concentration follows the order of leaf/needle > root > bark > branch > bole wood for each species. Total ecosystem mercury pool was 103.5 mg m−2and about 99.4% of the mercury resides in soil layers (0–40 cm). The remaining 0.6% (0.50 mg m−2) of mercury was stored in biomass. The large mercury stocks in the forest ecosystem pose a serious threat for large pluses to the atmospheric mercury during potential wildfires and additional ecological stress to forest insect: dung beetles, cicada and longicorn, with mercury concentration of 1983 ± 446, 49 ± 38 and 7 ± 5 ng g−1, respectively. Hence, the results obtained in the present study has implications for global estimates of mercury storage in forests, risks to forest insect and potential release to the atmosphere during wildfires.