Reitzel Kasper, Hansen Jonas, Andersen Frede O, Hansen Kjeld S, Jensen Henning S
Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
Environ Sci Technol. 2005 Jun 1;39(11):4134-40. doi: 10.1021/es0485964.
In the sediment of the shallow, hypertrophic Lake Sønderby, Denmark, potentially mobile phosphorus (Pmobile) was determined by a sequential extraction technique as the sum of porewater P, iron-bound P, and nonreactive P (i.e., polyphosphates and organic P). A good agreement was observed between loss rates of Pmobile in the top 10 cm of the sediment from winter to summer, P release rates measured in undisturbed sediment cores, and rates of P accumulation in the lake water from winter to summer (22, 32, and 30 mg of P m(-2) day(-1), respectively). This suggests that the operationally defined Pmobile was the sediment P fraction responsible for the internal loading in the lake. In autumn 2001, 11 mg of aluminum (Al) L(-1), equivalent to 31 g of Al m(-2), was added to the lake water. This dosage represented a 4:1 molar ratio between Al and Pmobile. The Al treatment significantly decreased lake water P, and P precipitated from the lake water was recovered as Al-bound P in the sediment after the treatment. Internal P loading was reduced by 93% in the two posttreatment years, relative to 2001. Accordingly, average summer concentrations of total P in lake water declined from 1.28 (SE = 0.17) and 1.3 (SE = 0.14) mg L(-1) in the two pretreatment years to 0.09 (SE = 0.01) and 0.13 (SE = 0.01) mg L(-1) in the posttreatment years. pH levels remained unchanged relative to pretreatment levels, while the total alkalinity was reduced from 3.2 (SE = 0.04) to 2.7 (SE = 0.03) mequiv L(-1).
在丹麦索nderby浅的富营养化湖泊的沉积物中，采用连续提取技术测定了潜在可移动磷（Pmobile），其为孔隙水磷、铁结合磷和非反应性磷（即多磷酸盐和有机磷）的总和。观察到沉积物顶部10厘米处从冬季到夏季Pmobile的损失率、在未扰动沉积物岩心中测得的磷释放率以及湖水中从冬季到夏季的磷积累率之间具有良好的一致性（分别为22、32和30毫克磷每平方米每天）。这表明按操作定义的Pmobile是湖泊内部负荷的沉积物磷组分。2001年秋季，向湖水中添加了11毫克铝（Al）每升，相当于31克铝每平方米。该剂量代表了铝与Pmobile之间4:1的摩尔比。铝处理显著降低了湖水磷含量，处理后从湖水中沉淀的磷在沉积物中以铝结合磷的形式回收。与2001年相比，处理后的两年内内部磷负荷降低了93%。相应地，湖水总磷的夏季平均浓度从预处理前两年的1.28（标准误 = 0.17）和1.3（标准误 = 0.14）毫克每升降至处理后两年的0.09（标准误 = 0.01）和0.13（标准误 = 0.01）毫克每升。pH水平相对于预处理水平保持不变，而总碱度从3.2（标准误 = 0.04）降至2.7（标准误 = 0.03）毫当量每升。
