雄烯二酮在我国典型土壤中的吸附特性

采用批吸附室内模拟实验研究了雄烯二酮在我国红壤、潮土、黑土3种典型土壤中的吸附特征,以及牛粪溶解态有机质(DOM)对土壤吸附雄烯二酮的影响。结果表明,雄烯二酮在土壤中吸附动力学符合Elovch方程(R20.89),热力学特征可通过Freundlich等温吸附方程(R20.83)描述,土壤对雄烯二酮的吸附呈非线性吸附特征,其中潮土吸附等温线的非线性最强(n=0.37);吸附系数K f介于6.0~20.2,并与有机质含量呈显著正相关(p0.05)。雄烯二酮浓度较低时,共存牛粪DOM抑制其在土壤表面的吸附作用。研究认为,有机质是土壤吸附雄烯二酮的主要组分,共存牛粪DOM可促进雄烯二酮向地表水和地下水的迁移。

Sorption of Androstenedione on Typical Soils of China

Batch equilibrium experiment was conducted to study the sorption characteristics of androstenedione to three typical soils of China (red soil, alluvial soil and black soil) and the influence of dissolved organic matter (DOM) in cattle manure on androstenedione sorption. The results indicated that the absorption of androstenedione was in accordance of the Elovch reaction kinetics in the entire stage (R²>0.89). Freundlich isotherm turned out to be statistically described the sorption of androstenedione to the soils (R²>0.83). Androstenedione adsorption nonlinearity was observed for the soils, the most isotherm deviation from linearity occurred in the alluvial soil (n=0.37). The sorption coefficient (k_f) ranged from 6.0 to 20.2 for the three soils, which showed a significant positive relation to the organic carbon content of each soil (p<0.05). Coexisted cattle manure DOM enhanced the androstenedione sorption at a lower concentration, while the opposite effect occurred when DOM concentration increased to high level. These results suggested that androstenedione was mostly adsorbed by the organic matter of soils, and coexisted cattle manure DOM could contribute to the transport of androstenedione to underground and surface water.