乌达煤田雾冰藜汞的初步调查

50多年前内蒙古乌海市乌达煤田随着工业采煤出现了煤层自燃亦称地下煤火,历经曲折的一轮又一轮治理,目前仍有火点分布。笔者等在深入煤田腹地调查基础上采用Lumex RA-915M/PYRO-915+汞分析仪检测了298件当地的戈壁草本植物雾冰藜(Bassia dasyphylla)的叶和茎样品。结果是:火点附近雾冰藜的叶汞含量总均值达到903ng/g,茎汞328ng/g;远离火点的煤田公路沿线雾冰藜的叶汞为131ng/g,茎汞62ng/g。表明:乌达煤田存在空气汞污染;污染源是区内煤层自燃;污染水平介于典型汞矿区与垃圾焚烧厂附近环境之间。建议:一年生草本雾冰藜有潜力成为空气汞污染的生物指示;它作为荒漠先锋植物很可能适于中国北方地下煤火的环境地球化学研究和调查。

Mercury Contents of Bassia dasyphylla around Undergoing Coal Fire in Wuda Coal Field, Wuhai, Inner Mongolia

The ongoing underground coal fire in Wuda coal field, Inner Mongolia, China started over 50 years ago and continues to pose environmental and biological hazards. To investigate its potential impact on local plantation, a total of 298 Bassia dasyphylla (sandwort) leaf and stem samples were collected at Wuda coal field, and the mercury level was determined by Lumex RA-915M/PYRO-915+ mercury analyzer. The average mercury concentration in the leaves and stems of B. dasyphylla sampled at coal fire area are 903 ng/g and 328 ng/g, and that in the leaf and stem samples collected alongside the main road of the coal field are 131 ng/g and 61.8 ng/g. The result suggests there is atmospheric mercury pollution within the whole coal field area, and the source is the underground coal fire. The pollution level is between typical mercury mine and garbage incinerator. Furthermore, the annual herb B. dasyphylla as a pioneer plant in arid land and desert proves to be a potential biological indicator of mercury pollution for the environmental and biogeochemical study of the prevailing underground coal fire in north China.