城市给水管网细菌再生长营养元素的试验研究

摘要

通过对南方某市给水管网10个取样点的水质分析,研究了细菌再生长所需的碳、磷浓度的临界值,利用可同化有机碳(AOC)和生物可利用磷(MAP)两个生物稳定性指标对该给水管网微生物生长的限制性营养因子进行了探讨.结果表明,管网水中细菌再生长所需碳和磷的临界值分别为300 μg Ac--C/L和5μg PO4--P/L.10个取样点在春、夏、秋、冬四季的AOCIP相较于AOCI的平均增长率分别为4.59％、3.64％、2.42％和43.42％,MAPIC相较于MAPI的平均增长率分别为56.11％、54.92％ 、60.83％和7.67％.在春、夏、秋三季,AOCI,＞ AOCI,MAPIC≈MAPI;在冬季,AOCIP≈AOCI,MAPIC＞ MAPI,表明管网各取样点水中细菌的再生长在春季、夏季和秋季受到碳元素限制,而冬季管网各取样点水中细菌的再生长受到磷元素的限制.研究成果可为保障给水管网供水的生物稳定性提供理论参考.%Through the water quality analysis of 10 sampling points from the drinking water distribution system of a southern city in China,the critical values of carbon and phosphorus required for bacterial regrowth were studied,and the limiting nutrient factors of the water supply network were discussed by two indexes:assimilable organic carbon (AOC) and microbially available phosphorus (MAP).Results showed that critical values of the carbon and phosphorus needed for bacterial regrowth in water supply network were 300 μg Ac--C/L and 5 μg PO43--P/L.In all seasons,average growth rates of AOCIPcompared to AOCI were 4.59％,3.64％,2.42％ and 43.42％,respectively,and average growth rates of MAPIC compared to MAPI were 56.11％,54.92％,60.83％ and 7.67％,respectively.In spring,summer and autumn,AOCIP ＞ AOCI,MAPIC ≈ MAPI,and in winter,AOCIP ≈ AOCI,MAPIC ＞ MAPI,which demonstrated that the bacterial regrowth of water supply distribution system in spring,summer and autumn was subject to carbon constraint,while in winter it was limited by phosphorus.The results of this study provide a theoretical reference for the biological stability of the supplied water of the drinking water distribution system.