水源型水庫的氮形態(tài)分布特征與水體富營養(yǎng)化的關系

詹志薇 譚志 金臘華 謝宏琴 張一凡 陳秋強

摘要根據(jù)實測水質(zhì)數(shù)據(jù)，對東莞市某備用水源水庫的氮形態(tài)分布特征及其與葉綠素a及水體綜合營養(yǎng)指數(shù)（TLT）的關系進行了分析，旨在為預防或減輕水體富營養(yǎng)化提供理論依據(jù)。結(jié)果表明：水源型水庫易受到營養(yǎng)性污染，呈中度或低度富營養(yǎng)化狀態(tài)；氮形態(tài)在水庫進水區(qū)以氨氮和硝酸鹽氮為主，且占比均在45%以上，出水區(qū)以硝酸鹽氮為主，且占比在75%以上，從進水區(qū)到出水區(qū)氨氮占比下降80%以上，季節(jié)變化對氮形態(tài)空間分布有一定影響，但影響程度不大；氨氮與葉綠素a和TLI無明顯的相關性，不對水體富營養(yǎng)化產(chǎn)生直接作用；硝酸鹽氮與葉綠素a和TLI呈負相關，對水體富營養(yǎng)化有一定的抑制作用；亞硝酸鹽氮和有機氮同葉綠素a以及TLI呈正相關，對水體富營養(yǎng)化有促進作用。降低排入水庫的氨氮和有機氮含量是有效預防或減輕水體富營養(yǎng)化的主要途徑。

關鍵詞水源型水庫；氮形態(tài)；葉綠素a；水體富營養(yǎng)化

中圖分類號S181.3文獻標識碼

A文章編號0517-6611（2017）10-0059-04

The Relationship between the Distribution of Nitrogen Forms and Eutrophication of Water Source Reservoirs

ZHAN Zhiwei1，TAN Zhi1，JIN Lahua2，CHEN Qiuqiang1* et al（1.Environmental Monitoring Center Station of Dongguan，Dongguan，Guangdong 523009；2.College of Environment，Jinan University，Guangzhou，Guangdong 510632）

AbstractBased on detected water quality data，the distribution characteristics of different form nitrogen and its relationships to chlorophyll a （Chla） and comprehensive nutrition status index of water body （TLI） in a reservoir as drinking water source in Dongguan were analyzed to provide theoretical bases for prevention and reduction of the eutrophication.The results showed that reservoirs of this kind may easily be polluted nutritionally and present moderate or low level of eutrophication，and the nitrogen form was given priority to ammonia nitrogen and nitrate nitrogen whose proportion was more than 45% respectively in the inflow area，but priority to nitrate nitrogen whose proportion was as high as 75% and above in the outflow area of the reservoir，also the proportion of ammonia nitrogen drops by 80% and above during the process from the inflow area to the outflow area，and moreover seasonal variation gives little impact to the spatial distribution of nitrogen forms.It has been found from the analyses that ammonia nitrogen has no obvious correlation with Chla and TLI and doesnt give direct contribution to the eutrophication，and nitrate nitrogen presents negative correlation with Chla and TLI and has a certain inhibitory effect to the eutrophication，but nitrite nitrogen and organic nitrogen positively relate with Chla and TLI so that it stimulates the eutrophication.To reduce the input amount of ammonia nitrogen and organic nitrogen into the reservoir was the main way to effectively prevent or mitigate eutrophication of water body in reservoirs.

Key wordsWater source reservoir；Nitrogen form；Chlorophyll a；Water body eutrophication

氮污染不僅對水庫水體富營養(yǎng)化有促進作用，而且會在飲用水氯消毒過程中生成具有強“三致”作用的含氮消毒副產(chǎn)物（N-DBPs），嚴重影響飲用水的安全。水中的氮形態(tài)包括無機氮和有機氮，其中無機氮以氨氮、硝酸鹽氮和亞硝酸鹽氮的形態(tài)出現(xiàn)。探明水庫水中不同形態(tài)氮的數(shù)量和變化特征，分析不同形態(tài)氮對水體富營養(yǎng)化的影響，對指導飲用水制取過程中科學選擇脫氮工藝及指導科學規(guī)劃與實施飲用水源保護具有重要的理論意義。……