摘要
为探究富营养化浅水湖泊所富集的有机物对湖泊碳循环和水质的影响,本研究构建微宇宙系统,模拟蓝藻和芦苇碎屑单独分解及混合分解过程.通过测定各组上覆水营养盐浓度、有机质含量及结构的变化,揭示富营养化湖泊藻草残体混合分解过程中养分和有机碳的释放特征.结果表明,在实验0-88 h内,在添加相同的碳源条件下,蓝藻和芦苇混合处理组总碳(TC)释放量显著高于理论值,表明藻草碎屑混合分解存在共代谢效应.在培养初期,沉积物通过共代谢效应对水质产生了较大的影响,加速向水体中释放氮、磷物质.相较单独的植物分解,混合处理组中总氮(TN)、总磷(TP)的最大释放量分别提高了13.49%和26.84%;通过三维荧光光谱表征的类富里酸荧光强度变化也表明:较芦苇处理组,混合处理组中芦苇的分解速率更快.在培养开始后,各处理组均快速转变为厌氧状态,TC、TN、TP浓度随时间变化总体上呈先快速上升再逐渐平缓的趋势,分别在第228、108和324小时达最大值(372.4±2.98)、(138.45±2.97)和(7.95±1.11)mg/L.细菌特异性脂肪酸含量变化表明,将蓝藻碎屑添加到芦苇碎屑中,会增加芦苇碎屑中细菌的丰度,从而提高分解速率,激发共代谢效应.在全球气候变暖的背景下,随着富营养化湖泊藻类暴发频次增加,共代谢效应可能还会进一步加强,对富营养化湖泊水质将会持续产生影响.
In order to explore the effect of enriched organic matter in eutrophic shallow lakes on water quality and carbon cycle,in this study,we constructed a microcosm system to simulate the separate decomposition and mixed decomposition of cyanobacteria and reed debris.The changes of nutrient concentration,organic matter content and structure of the overlying water in each treatment were determined to reveal the release characteristics of nutrients and organic carbon during the mixed decomposition process of cyanobacteria and reed debris in eutrophic lakes.The results showed that the total carbon(TC)release of the mixed treatment was significantly higher than the theoretical value within 0-88 hours of the experiment under the same carbon source addition,indicating that there is a co-metabolism effect during the mixed decomposition of cyanobacteria and reed debris.In the initial stage of the cultivation,sediments accelerated the release of total nitrogen(TN)and total phosphorus(TP)to the overlying water and caused a significant impact on the water quality via the co-metabolism effect.Compared with the reed treatment,the maximal release of TN and TP in the mixed treatment increased by 13.49%and 26.84%,respectively.The change of fluorescence intensity of fulvic acid characterized by the three-dimensional fluorescence spectroscopy(EEMs)also showed that the decomposition rate of reed was faster in the mixed treatment group.At the beginning of cultivation,each treatment quickly turned into anaerobic state,and the concentration of TC,TN and TP displayed a trend of dramatical increase and then gradually flattened,with a maximum of(372.4±2.98),(138.45±2.97),and(7.95±1.11)mg/L at 228,108 and 324 hours,respectively.The variations of bacterial specific fatty acid showed that the input of Microcysti s detritus into Phragmites detritus increased the abundance of decomposing bacteria in Phragmites detritus,and accelerated the decomposition rates,resulting in the co-metabolism of Microcystis and Phragmites carbon.Under the backgroun
作者
石瑞洁
马杰
吕成旭
许晓光
党馨逸
蒋燕妮
叶子
吴懿婷
王国祥
Shi Ruijie;Ma Jie;Lv Chengxu;Xu Xiaoguang;Dang Xinyi;Jiang Yanni;Ye Zi;Wu Yiting;Wang Guoxiang(School of Environment,Nanjing Normal University,Nanjing 210023,P.R.China;Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application,Jiangsu Key Laboratory of Environmental Change and Ecological Construction,Jiangsu Engineering Lab of Water and Soil Eco-remediation,Nanjing 210023,P.R.China)
出处
《湖泊科学》
EI
CAS
CSCD
北大核心
2021年第4期1062-1071,共10页
Journal of Lake Sciences
基金
国家水体污染控制与治理科技重大专项(2017ZX07203-003)
国家自然科学基金项目(42077294,41703105)联合资助.
