菹草种群内外溶解氧空间分布日变化研究  

Diurnal Variation of Dissolved Oxygen in the Spatial Distribution Around Potamogeton crispus Population

作　　者：王锦旗[1] 郑有飞[1] 王国祥[2] 

机构地区：[1]南京信息工程大学环境科学与工程学院,南京210044 [2]南京师范大学地理科学学院,南京210097

出　　处：《农业环境科学学报》2013年第4期748-755,共8页Journal of Agro-Environment Science

基　　金：国家自然科学基金(41105113)

摘　　要：溶解氧(DO)是衡量水体污染程度的重要指标,为研究菹草种群生长对湖泊水体水质的影响,对南京玄武湖菹草种群内外水体DO含量进行了连续一昼夜的监测,结果表明菹草种群光合作用对水体DO影响显著。时间分布上,种群区水体DO日出后增加,日落后下降,水下20～80cm19:30左右出现1次下降现象,稍后略有恢复,其后持续降至日出前后,而较深的100cm处无此现象;开阔水域日出后持续升高至日落,日落后下降直至日出前后,且各深度差异不大;交界处呈现种群内的特点,同时具有开阔水域变化趋势。垂直分布上,种群区白天从表层向底层逐渐递减,夜间20～40cm处较低,100cm处也较低,60～80cm处较高;而离种群较远的开阔水域昼夜均从表层向底层递减,离种群较近的开阔水域因水深较浅,各深度差异不大;交界处昼夜均从表层向底层递减。水平分布上,种群内侧点各水深处各时刻始终最高,20～40cm深离开阔水域较近种群外侧点最低;60cm深白天离开阔水域较近种群外侧点最低,夜间交界处最低;80cm深交界处最低;100cm深夜间从种群内侧向开阔水域依次降低,白天规律性不明显。菹草种群对提高水体DO起到积极作用,并对周围水域有一定的影响。Dissolved oxygen（DO） is an important indicator for water pollution. In order to study the effects of Potamogeton crispus population on water quality, the DO content around the P. crispus population was monitored in Xuanwu Lake in Nanjing. The result showed that the pho- tosynthesis of P. crispus significantly improved DO content in the water. （ 1 ）DO content within the P. crispus population was generally higher during daytime than that during the night. DO content increased after sunrise and declined after sunset; it dropped at 19：30 at 20--80 cm depth, then recovered slightly from 21：30 and finally dropped until sunrise. DO content at the open waters increased continuously from sun- rise to sunset, and dropped from sunset to sunrise. DO content did not show significant difference at each water depth. DO content in the junction water area showed similar phenomenon with that within population and the open waters. （2）DO content within water containing P. crispus population decreased from the surface to the bottom during daytime; DO content was higher at 60-80 cm than that at both 20-40 cm and 100 cm during the night. DO content, which was far away from P. crispus population in the open waters decreased from the surface to the bottom, while DO content in the open waters close to the population showed no significant differences at each depth because the water area was relatively shallow. DO content in the junction area decreased from the surface to the bottom during both the daytime and night. （3）DO content for the water surrounding the population was the highest at all periods and all depths; DO content which is outside the water contain- ing population and close to the open water was the lowest at 20--40 cm. During the daytime, DO content in the water containing population and close to the open water was lowest at 60 cm, while it was the lowest in the junction water at night. DO content in the water containing population was the highest in 80 cm depth; it was the lowest in the junction water. DO

关 键 词：湖泊 菹草(Potamogeton CRISPUS L ) 溶解氧 垂直分布 水平分布 

分 类 号：X524[环境科学与工程—环境工程]