| 引用本文: | 刘尚武,张小峰,吕平毓,兰峰.金沙江下游梯级水库对氮、磷营养盐的滞留效应.湖泊科学,2019,31(3):656-666. DOI:10.18307/2019.0305 |
| LIU Shangwu,ZHANG Xiaofeng,LV Pingyu,LAN Feng.Effects of cascade reservoirs in the lower reaches of Jinsha River on nitrogen and phosphorus retention. J. Lake Sci.2019,31(3):656-666. DOI:10.18307/2019.0305 |
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| 摘要: |
| 氮、磷是水域重要的营养或污染物质，大型水库修建将对江河氮、磷物质的输运产生重要影响.以金沙江华弹、向家坝水文站2006-2016年实测水质资料为依据，通过建立污染物浓度与流量比值（TN/Q、TP/Q）与含沙量（S）的关系式，对金沙江下游溪洛渡、向家坝梯级水库蓄水前后进出库总氮（TN）、总磷（TP）浓度及通量的变化特征进行研究.结果表明：（1）华弹站不受蓄水影响，TN和TP浓度在0.38~1.41和0.01~0.73 mg/L之间变化，向家坝站蓄水前TN和TP浓度在0.32~1.33和0.03~0.42 mg/L之间变化，蓄水后在0.35~1.29和0.01~0.05 mg/L之间变化，蓄水后TN浓度较蓄水前略有升高，但TP浓度较蓄水前约降低75%；（2）蓄水前华弹站TN浓度与向家坝站基本接近，TP浓度总体低于向家坝站，蓄水后华弹站TN浓度低于向家坝站，TP浓度明显高于向家坝站；（3）金沙江TN以硝态氮（NO3--N）为主，占TN浓度的67.3%~91.8%；（4）两站的TN浓度随流量和含沙量变化较小，TP浓度与流量和含沙量均呈正相关关系；（5）华弹站TN、TP年通量在48357~135827和4720~14163 t之间变化，年均值分别为90337和8932 t，向家坝站蓄水前后TN年通量在64232~130966和71675~149647 t之间变化，蓄水后通量总体高于蓄水前，TP年通量在8851~18624和3131~7300 t之间变化，蓄水后通量远低于蓄水前；（6）水库蓄水对出库TN浓度与通量无明显影响，但TP浓度与通量较蓄水前明显降低，其中通量年均滞留率约为67.0%. |
| 关键词: 金沙江 总氮 总磷 滞留效应 梯级水库 |
| DOI：10.18307/2019.0305 |
| 分类号: |
| 基金项目:国家重点研发计划项目（2016YFA0600901）资助. |
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| Effects of cascade reservoirs in the lower reaches of Jinsha River on nitrogen and phosphorus retention |
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LIU Shangwu1, ZHANG Xiaofeng1, LV Pingyu2, LAN Feng2
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1.State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, P.R.China;2.Water Environment Monitoring Office on the Yangtze River, Chongqing 400010, P.R.China
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| Abstract: |
| Nitrogen and phosphorus were important nutrients or pollutants in water. The construction of large reservoirs would have a profound impact on their transmission characteristics. Based on the measured water quality data of Huatan and Xiangjiaba hydrological stations from 2006 to 2016 in Jinsha River, the relationships between TN/Q, TP/Q and sediment concentration (S) were established, and the change characteristics of total nitrogen (TN) and total phosphorus (TP) concentrations and flux before and after Xiluodu and Xiangjiaba cascade reservoirs were studied. The result showed as follow:(1)The concentrations of TN and TP were 0.38-1.41 mg/L and 0.01-0.73 mg/L in Xiangjiaba Station, the concentrations of TN and TP were 0.32-1.33 mg/L and 0.03-0.42 mg/L before impoundment, the concentrations of TN and TP were 0.35-1.29 mg/L and 0.01-0.05 mg/L after impoundment in Xiangjiaba Station, the concentration of TP decreased by about 75% compared with that before impoundment. (2) The concentration of TN in Huatan Station was close to Xiangjiaba Station, and the concentration of TP in Huatan Station was less than that in Xiangjiaba Station before impoundment. But after impoundment, the concentration of TN in Huatan Station was less than that in Xiangjiaba Station, and the concentration of TP in Huatan Station was obviously more than that in Xiangjiangba Sation. (3)The concentration of TN in Jinshajiang River was dominated by NO3--N, accounting for 67.3%-91.8%. (4)The concentration of TN had a little relationship with flow and sediment concentration, and the concentration of TP had positive relationships with flow and sediment concentration. (5)The fluxes of TN and TP in Huatan Station were 48357-135827 and 4720-14163 t, with the mean values of 90337 and 8932 t, respectively. The flux of TN were 64232-130966 and 71675-149647 t, and the flux of TP were 8851-18624 and 3131-7300 t before and after impoundment in Xiajiaba Station. (6)TN concentration and discharge had no significant effect after reservoir impoundment, but TP concentration and flux were significantly reduced, the annual retention rate was about 67.0%. |
| Key words: Jinsha River total nitrogen total phosphorus retention effect cascade reservoir |
