北方高盐景观水体氮磷时空分布特征及富营养化评价

为掌握北方高盐景观水体的水环境状况,选取天津市中新生态城3个景观水体(清净湖、蓟运河和蓟运河故道)为研究对象,于2013年12月—2014年11月对其进行定期取样监测,开展水体氮磷污染特征分析及富营养化评价。结果表明:1)蓟运河、清净湖和蓟运河故道的TDS均值分别为3.42,4.64,20.2 g/L,属于高盐景观水体;2)水体TN和TP浓度逐月变化显著,水质整体上冬春季优于夏秋季,其中蓟运河TP和TN的浓度最大,且波动较大;3)根据TN/TP比值判定,研究区水体除清净湖在短时间表现为氮限制外,水体大部分时间段内表现为磷限制,P为主要限制因子;4)富营养化评价表明:水体均处于富营养状态,且有蓟运河>蓟运河故道>清净湖;5)相关性结果表明:TDS与电导率、水温及EI呈显著正相关,相关系数分别为0.905、0.822和0.645,盐度也是影响富营养化的关键因素。

RISK PREDICTION AND EARLY WARNING OF EUTROPHICATION IN HUANREN RESERVOIR

Nutritional status and spatial-temporal variations in each section of Huanren Reservoir was evaluated by comprehensive nutrition state index method,based on monitoring data from 2005 to 2015 of Huanren Reservoir in Liaoning Province.Expected values of comprehensive nutrition state index in next five years were predicted using unitary linearity regression model.The distributions of the nutrient index conform to the law of normal distribution proved by Kolmogorov-Smirnov test.Furthermore,eutrophication risk of each reservoir section in next 5 years was predicted using cumulative density function.As a result,reservoir head region would transform into high-risk area (81.70％) since 2019,while the risk of middle region would be relatively low (38.97％ and 34.66％),and the tail section would face very low risk (3.42％).Urban domestic sewage collection and treatment and agricultural non-point pollution management in upstream region should be strengthened to control eutrophication risk of Huanren Reservoir.