我国典型湖泊磷浓度对水体指标及蓝藻水华爆发趋势的潜在影响--基于Meta分析

The potential impact of phosphorus concentration in typical lakes in China on water body indicators and cyanobacteria bloom trends based on meta-analysis

水体富营养化可引发蓝藻水华,对水生态环境和饮用水的安全产生严重危害,揭示蓝藻水华的发生机理和变化规律是防治的基础。基于1989-2019年公开发表的相关研究,提取583对有效数据,利用Meta分析了我国典型湖泊中磷浓度对水体指标及蓝藻水华爆发趋势的影响。结果表明:磷浓度对水体透明度(SD)产生负效应,对溶解氧(DO)含量、高锰酸盐指数(CODMn)和叶绿素a(Chla)含量产生正效应。随着磷浓度的增加,上述4种指标呈现不同的变化趋势:磷浓度对DO含量的正效应逐渐转变为负效应,在磷的质量浓度为0.2~0.3 mg/L时负效应最大(亚热带季风气候);对SD的负效应随磷浓度的增加先增大后略有减小,在磷的质量浓度为0.1~0.2 mg/L时负效应最大;CODMn和Chla含量对磷浓度的响应趋势基本相似,在亚热带季风气候条件下,磷的质量浓度分别为0.2~0.3 mg/L和>0.3 mg/L时二者的正效应最大。此外,与温带季风气候地区相比,在磷的质量浓度为0~0.1 mg/L时亚热带季风气候地区的湖泊水质更容易受磷浓度的影响,蓝藻水华爆发的风险相对较高。

Eutrophication of water bodies can cause cyanobacteria bloom,which does serious harm to the aquatic ecological environment and the safety of drinking water.Understanding the underlying occurrence mechanism and the factors affecting the variation in cyanobacteria bloom is the basis of prevention and control.Based on relevant studies published from 1989 to 2019,583 pairs of effective data were extracted and meta-analysis was used to study the effects of phosphorus concentration on water indexes and the outbreak trend of cyanobacteria blooms in typical lakes in China.The results showed that phosphorus concentrations had a negative effect on water transparency(SD)and a positive effect on dissolved oxygen(DO)content,permanganate index(CODMn)and chlorophyll a(Chla)content.With a further increase in phosphorus concentration,the above four indexes showed different trends.The positive effect of phosphorus concentration on DO content gradually changed into negative effect,and the negative effect was the greatest when the phosphorus concentration was 0.2-0.3 mg/L(subtropical monsoon climate).The negative effect on SD increased at first and then decreased slightly with increasing phosphorus concentration,and the negative effect reached a maximum when the phosphorus concentration was 0.1-0.2 mg/L.The response trends of CODMn and Chla content to increasing phosphorus concentration were similar,and under subtropical monsoon climate,the positive effects of phosphorus concentration reached their maximum when the phosphorus concentration were 0.2-0.3 mg/L and>0.3 mg/L respectively.In addition,compared with the temperate monsoon climate,the lake water quality in a subtropical monsoon climate is more seriously affected by phosphorus concentration when phosphorus concentration was 0-0.1 mg/L,and the risk of cyanobacteria bloom outbreak is higher.