Characterizing the purification effect on the ecological reservoir and its influencing factors

Abstract

水库水体污染控制及富营养化防治是保障城市原水供应安全的重要环节.本研究针对金泽水源水库太浦河来水氮、磷浓度较高的特点，自行设计建设了5个面积均为240 m²的生态净化模拟试验池（A、B、C、D和对照）开展模拟试验，研究了不同水库形态、水生植物种植面积比例及种植方式对水体氮、磷污染物去除的影响.结果表明，通过模拟试验池的生态净化，原水中铵态氮（NH₄⁺-N）、总磷（TP）和总氮（TN）的平均去除率分别为50.36%、53.73%和22.25%，C池TN和NH₄⁺-N去除率最高分别达到了24.97%和54.61%，D池TP去除率最高，达到62.16%，水体溶解氧（DO）平均浓度提高了1.11 mg/L，平均透明度提高了27.6 cm，均显著高于对照池.水库形态结构、水生植物面积比例及种植方式对水体氮、磷污染物净化效果影响明显，增大水库浅水区面积能有效提高对水体氮、磷污染物的去除能力，增加水生植物种植面积能有效提高水体氮污染物去除和DO、透明度的提升能力，采用浮床种植方式能有效提高水体磷污染物去除和透明度提升能力.本研究结果能为金泽水源水库及其他类似水库的设计和建设提供科学依据.;Water pollution and eutrophication control in reservoirs are important to ensure the safety of urban water supply. Four ecological purification pilot reservoirs (A, B, C and D) and one controlled reservoir with 240 m² area were constructed in Linjiang Water Plant characterized by high concentrations of nitrogen and phosphorus. The effects of different reservoir configurations, the proportion of aquatic plant planting area, and planting methods on the removal of total nitrogen (TN) and total phosphorus (TP) were determined according to the pilot reserves. The results showed that the average removal rates of ammonium nitrogen (NH₄⁺-N), TP and TN for the inflow water were 50.36%, 53.73% and 22.25% by the ecological purification of the pilot reservoirs, respectively; C reservoir had the highest removal rates of TN and NH₄⁺-N of 24.97% and 54.61%, respectively; the highest removal rate of TP was found at D reservoir of 62.16%; the average dissolved oxygen (DO) concentration and transparency of the four pilot reservoirs increased by 1.11 mg/L and 27.6 cm, respectively, which was significantly higher than those of the controlled reservoir. The shape and structure of the reservoirs, the proportion of aquatic plant planting area, and the planting methods had obvious influences on the purification of TN and TP. The increase of shallow water area can effectively improve the removal of TN and TP; the increase of the planting area of aquatic plants can effectively increase DO concentration, improve the removal of TN, and enhance the transparency; the planting method of floating bed can effectively promote the removal of TP and enhance the transparency. The results of this study provide a scientific basis for the design and construction of Jinze Reservoir and other similar reservoirs as water sources.