库布齐沙漠恩格贝沙样中磷的化学赋存形态

通过采用七步连续萃取法对库布齐沙漠恩格贝沙样磷形态的分析,揭示了恩格贝沙样中磷的各种存在形态及含量分布。结果表明：所取沙样中总磷 (TP) 含量在94.33~251.04 μg·g-1 之间,且含量随沙样粒径的减小而增大。无机磷（IP）含量在 88.75~234.83 μg·g-1 之间,占TP含量的 94.08%~93.54%,其中以自生钙结合磷（Ca-P）和原生碎屑磷（De-P）为主,二者占到TP 含量的82.81%~86.13%。有机磷（Or-P）含量在5.58~16.21 μg·g-1之间,占总磷的5.91%~6.46%。在所有不同粒径沙样中各形态磷含量的高低顺序为：原生碎屑磷（De-P）、自生钙结合磷（Ca-P）、有机磷（Or-P）、吸附态磷（Ads-P）、铁磷（Fe-P）、铝磷（Al-P）、闭蓄态磷（Obs-P）,其中Obs-P含量极微。在所取沙样中 Ads-P、Fe-P、De-P、Or-P、Al-P、Obs-P 各自含量都随颗粒物粒径的减小而增大,但Al-P和Obs-P的变化幅度很小。而Ca-P含量受粒径影响较小,粗颗粒沙样中含量略高一些。

Various Forms of Phosphorus in Engebei Sands of Hobq Desert

The Engebei sands from Hobqi Desert were analyzed with the sequential extraction method, and the various forms of phosphorus and their content distributions were revealed. The results showed that the concentration of total phosphorus (TP) in Engebei sands of Hobqi Desert ranges from 94.33 μg·g-1 to 251.04 μg·g-1, which increases with sand particle size decreasing. Inorganic phosphorus (IP) is found to be the major phosphorus form of TP and its content ranges from 88.75 μg·g-1 to 234.83 μg·g-1, and its main composition is Ca-P and De-P, of which the ratio to TP is from 82.81% to 86.13%. Or-P ratio to TP is from 5.91% to 6.46%. De-P is found to be the major phosphorus form in all the different particle size sands and Ca-P the second, Or-P the third, Ads-P the fourth, Fe-P the fifth, Al-P the sixth and Obs-P exists in very minute quantities. The contents of various phosphorus forms increase with sand particle size decreasing except Ca-P which has no obvious change.