黄河高村至利津河段水体和沉积物中不同形态磷的分布特征

Distribution of Different Phosphorus Species in Water and Sediments from Gaocun to Lijin Reaches of the Yellow River

黄河是我国第二大河流,其对营养盐的输送在区域乃至全球范围内扮演着很重要的角色.本研究对黄河高村至利津河段5个站点两季水体和沉积物中不同形态磷的分布特征进行了研究.结果表明,黄河高村至利津河段水体5月处于磷污染状态,5月水体总磷(TP)变化范围为0.05~2.31 mg·L^(-1),9月为0.03~0.1 mg·L^(-1),颗粒态磷(PP)为主要赋存形态,TP与PP呈极显著相关(P<0.01),径流量和水体TP与PP显著正相关(P<0.05),总溶解性磷(TDP)与溶解性无机磷(DIP)显著负相关(P<0.05,P<0.01),流量增加对TDP和DIP的稀释作用很明显,但黄河高村至利津河段土壤磷流失仍然很严重.水体悬浮颗粒物(SPM)质量浓度与DIP显著负相关(P<0.01),SPM对水体DIP的吸附作用明显;秋季水体高锰酸盐指数较春季高,受有机物污染更严重,水体高锰酸盐指数与DIP质量浓度显著正相关(P<0.01).黄河高村至利津河段沉积物两季总磷的含量基本处于未污染水平,沉积物TP 5月变化范围为284.23~569.58 mg·kg^(-1),9月为287.97~355.39 mg·kg^(-1),钙磷(CaP)为无机磷(IP)的主要赋存形态.活性有机磷(L-OP)含量与径流量,水体SPM质量浓度和高锰酸盐指数显著相关(P<0.01,P<0.05,P<0.01),5月利津站点的有机磷(OP)含量明显较高,可能是降雨冲刷流域内矿物开采区导致的,黄河高村至利津河段能源基地生产活动需要密切关注.

The Yellow River is the second longest river in China,which plays a very important role in the transportation of nutrients at the regional and even global scale. Water and sediment samples were collected at five sites located at the Gaocun to Lijin reaches along the Yellow River and the distribution characteristics of different phosphorus species were analyzed. The concentration of suspended particulate matter（ SPM） in water ranged from 1. 89 to 2. 67 g·L^-1with an average of 2. 26 g·L^-1in May and from 0. 43 to 1. 79g·L^-1with an average of 1. 21 g·L^-1in September. It almost had the same variation rule as the water flux,which reflects the influence of water flux on SPM transportation. The concentration of total phosphorus（ TP） in water ranged from 0. 05 to 2. 31 mg·L^-1in May and from 0. 03 to 0. 1 mg·L^-1in September. Particulate phosphorus（ PP） was the dominant TP species in both months,and TP and PP were significantly correlated（ P〈0. 01）,which implied that phosphorus loss in soil from Gaocun to Lijin reaches is still serious.Water runoff was positively correlated with TP and PP（ P〈0. 05）,but negatively correlated with total dissolved phosphorus（ TDP）and dissolved inorganic phosphorus（ DIP）（ P〈0. 05,P〈0. 01,respectively）. Increasing water runoff obviously increased the dilution of TDP and DIP. The concentration of SPM was negatively correlated with DIP（ P〈0. 01）,the adsorption of SPM on phosphorus was mainly the adsorption of DIP. The permanganate index in water was higher in fall suggesting more serious organic pollution and it was positively correlated with DIP（ P〈0. 01）. The phosphorus content in sediments was quite low in both months; the total phosphorus（ TP） content in sediments ranged from 284. 23 to 569. 58 mg·kg^-1in May and from 287. 97 to 355. 39 mg·kg^-1in September. Calcium-bound phosphate（ Ca-P） was the dominant species of inorganic phosphorus（ IP）. The labile organic phosphorus（ L-OP） content was significantly correlated with runoff,SPM concentration,and permanganate index（ P〈0. 01,P〈0. 05,P〈0. 01,respectively）. The organic phosphorus（ OP） content was significantly higher at the Lijin site in May,likely caused by the rainfallrunoff from the mining area around Lijin. The energy-based production activities from the Gaocun to Lijin reaches should also be further investigated.