CAJ | 학술논문

采用平衡解吸法研究了沉积物不同有机矿质复合体对磷的解吸特征影响.结果表明,通过过氧化氢去除腐殖质后沉积物磷的解吸比例(Dr=0.65)大幅度增加,解吸迟滞性指数(TⅡ=0.01)显著降低,有机矿质复合体是影响磷在沉积物上固持特征的重要因素;磷在钙键和铁铝键有机矿质复体团聚结构微孔隙中引起的团聚体结构不可逆形变是导致磷解吸比例降低、解吸迟滞性指数增大的原因之一.铁铝键有机矿质复合体(Dr=0.17、TⅡ=0.32)对磷的固持能力强于钙键复合体(Dr=0.25、TⅡ=0.22),其因原因有二,三价的铁铝离子与二价的钙离子相比,更有利于复合结构的形成,铁铝键有机矿质复合体除对团聚体结构形成有重要影响外,还存在铁铝氧化物及水化氧化物对磷的配位吸附作用(相当于化学吸附),因而铁铝键有机矿质复合体对磷的固持能力比钙键复合体强得多;考查沉积物对磷的解吸特征不但要考虑腐殖质的含量,更要考虑腐殖质的复合形态,它也是影响沉积物磷解吸特征的重要因素,铁铝键有机矿质复合体、钙键有机矿质复合体携载的吸附态磷对上覆水体的释放通量可分别按其饱和吸附量17%和25%估算.
채용평형해흡법연구료침적물불동유궤광질복합체대린적해흡특정영향.결과표명,통과과양화경거제부식질후침적물린적해흡비례(Dr=0.65)대폭도증가,해흡지체성지수(TⅡ=0.01)현저강저,유궤광질복합체시영향린재침적물상고지특정적중요인소;린재개건화철려건유궤광질복체단취결구미공극중인기적단취체결구불가역형변시도치린해흡비례강저、해흡지체성지수증대적원인지일.철려건유궤광질복합체(Dr=0.17、TⅡ=0.32)대린적고지능력강우개건복합체(Dr=0.25、TⅡ=0.22),기인원인유이,삼개적철려리자여이개적개리자상비,경유리우복합결구적형성,철려건유궤광질복합체제대단취체결구형성유중요영향외,환존재철려양화물급수화양화물대린적배위흡부작용(상당우화학흡부),인이철려건유궤광질복합체대린적고지능력비개건복합체강득다;고사침적물대린적해흡특정불단요고필부식질적함량,경요고필부식질적복합형태,타야시영향침적물린해흡특정적중요인소,철려건유궤광질복합체、개건유궤광질복합체휴재적흡부태린대상복수체적석방통량가분별안기포화흡부량17%화25%고산.
Effect of different organo-mineral complexes on desorption characteristic of phosphorus on sediment was investigated by batch experiment of equilibrium desorption. Results indicated that desorption ratio increased dramatically after humus was removed by H2O2 (Dr=0.65), and desorption hysteresis index decreased simultaneously (TⅡ=0.01). Organo-mineral complex was a main influencing factor in fixed and maintained characteristic of phosphorus on sediment. On the one hand, the irreversible transformation of aggregate structure on Fe/Al-bound or Ca-bound complex was fundamental cause of desorption ratio lower and hysteresis index higher. On the other hand, fixed and maintained capacity of Fe/Al-bound complex (Dr=0.17、TⅡ=0.32) was higher than Ca-bound complex (Dr=0.25、TⅡ=0.22), (1)Trivalent iron ion was more favorable for complex structure formation than divalent calcium ion. (2)Besides Fe/Al-bound complex had a great effect upon aggregate structure formation, there was a Fe/Al oxide or hydration oxide coordination sorption (chemical sorption) of phosphorus on sediment. Taking into account desorption characteristic was not only humus content, but also compound state of humus, as it was also an important factor. When regarded sorption capacity as a basic standard, releasing flux of adsorption state phosphorus on Ca-bound complex and Fe/Al-bound complex were also estimated in accordance with 25%and 17%.