内蒙古西部沙漠颗粒物磷的化学形态研究

Chemical speciation of phosphorus in desert particles from western Inner Mongolia

文中用一种连续萃取方法(SEDEX)分析了内蒙古西部沙漠<63μm颗粒物磷的五种形态:可交换态磷P_(ex);铁结合态磷P_(Fe);自生碳酸盐氟磷灰石+CaCO_3缔合磷P_(au);由岩屑形成磷灰石磷(P_(det))和有机磷(P_(org))。研究得出以下结论:1)内蒙古西部沙漠颗粒物中的磷以Pau为主,在自然粒径的颗粒物样品中P_(au)在154.44~1836.66mg·Kg^(-1),P_(au)含量与颗粒物粒径成反比,即粒径越小,含量越高。其次是P_(det),含量在8.12~477.72mg·Kg^(-1)。其他两种较易被生物利用的P(P_(ex)、P_(Fe))的总和为19.71~44.63mg·Kg^(-1),占TP的0.27%~8.51%;2)两种粒度相比,TP含量顺序均为甘肃临泽>巴丹吉林(阿右旗)>巴丹吉林(嘎顺诺尔)>乌兰布和(巴彦高勒)>腾格里(阿左旗)>巴丹吉林(八道桥)。作为沙尘暴源头,<63μm颗粒物易形成高空飞尘,飘过我国东部海区至太平洋,远距离输送了磷。

In this study, a sequential extraction method （SEDEX） was developed to separate live particles loosely sorbed p （ Pex）, ferric iron - bound p （ Pre）, authigenic carbonate fluorapatite ＋ biogenic apatite ＋ CaCO3 asso- ciated p （Pau）, detrital apatite P （Pdet） and organic P （Porg）＂ We reached the following conclusion： （1）The contents of Pau in sands with natural grain size collected from western deserts of Inner Mongolia are 154. 444mg·Kg^-1 - 1836. 664mg ·Kg^-1. The contents of Pau is in reverse proportion to the particle size, that the smaller of the grain size, the higher the contents. The next is Pdet, its content is 8. 514mg · Kg^-1 -477. 724mg · Kg^-1. The other two P that are easily used by plants their total content is 19.71-44. 634mg· Kg^-1 , accounting for 0. 27% -8.57% of the total P. （2） For the TP in the sand samples with different particle sizes, the TP are （Gan- Su - Linze） 〉 Badanjiein （ Alashom youqi） 〉 Badanjilin （ Shanga nwoer） 〉 Ulan Buh Desert （ Baying - gaule ） 〉 Tengel - li（Azuoqi） 〉 Badanjilin（ Batong - bridge）. As source of sand storm, the particles 〈 63 μm carried p fly from Inner Mongolia to the East China Sea and the Pacific Ocean, and transported P long distance.