综合水质标识指数法在水库季节性污染时空分布评估中的应用

文章结合水质标识指数方法对辽宁西部某供水水库的季节性污染时空特征进行评估,并对其水质季节性变化的成因进行探讨。结果表明:研究水库在丰水期水质总体达II类水标准,总体达标率高于80%,而在枯水期由于水量锐减,进入水库的污染物浓度下降明显,可达III类水标准,总体达标率低于60%,但在丰水期水库水体富营养化程度高于枯水期,丰水期发生富营养化总体风险几率较高。通过对沿程水质监测断面的追踪分析,城市生活点源排放是研究水库水体季节性变化特征的主因。从上游到下游监测断面,水库沿程污染指数空间变化整体呈现增加趋势。

浅析眉山市主城区臭氧污染

通过对近三年国控站点监测数据统计,分析眉山市主城区污染物的季节性变化特征以及首要污染物对环境空气优良率的贡献比例。夏季的臭氧污染已成为制约空气质量优良率的主要因素,今年6月共出现了4次臭氧污染过程。因此,着重对2021年6月环境空气质量监测数据、臭氧污染过程、环境气象因素三者之间的关系进行浅析,同时对主城区形成臭氧的前体污染物组分进行定性和定量的分析,从而找出导致本地臭氧污染的源头,进一步分类治理从而提升环境空气质量。

Seasonal variation in imposex intensity of Thais clavigera

Imposex, specifically caused by TBT pollution, refers to the superimposition of male sexual characteristics in gastropod females. Seasonal variation of imposex intensity in Thais clavigera from both slightly and severely contaminated sites in Hong Kong waters was studied from 1988 to 1999. The male penis length showed significant difference between both sites and seasons. It was shortest during late autumn and early winter (October to December) and longest during spring and early summer (February to June). Female penis length also showed significant difference between sites. It did not change seasonally, however. The RPS (Relative Penis Size) index was the highest during autumn and early winter, and the lowest during spring and early summer. The VDS (Vas Deferens Sequence) index remained stable throughout the sampling period. This study showed that VDS index is a better indicator when we compare relative intensity of imposex. The comparison can only be meaningful provided the samples from different locations are taken during the same season.