水华初期蓝藻颗粒有机物在不同菌群作用下分解释放营养盐的过程研究  

Processes of nutrients release from particulate organic matter derived from cyanobacterial blooms in early stage by different microflora

作　　者：黄亚新[1,2] 张小倩 杨燕[1] 孔繁翔 卢亚萍[1] 施丽梅[2] HUANG Yaxin;ZHANG Xiaoqian;YANG Yan;KONG Fanxiang;LU Yaping;SHI Limei(College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China;State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China)

机构地区：[1]南京农业大学生命科学学院,南京210095 [2]中国科学院南京地理与湖泊研究所,湖泊与环境国家重点实验室,南京210008

出　　处：《生态科学》2017年第5期55-63,共9页Ecological Science

基　　金：江苏省自然科学基金项目(BK20131466);国家自然科学基金项目(31370509)

摘　　要：蓝藻水华为富营养化湖泊制造了大量有机物,这些藻源有机物的分解影响了水体中的营养盐循环。通过室内模拟附生细菌(A),附生细菌与游离细菌(AF),及附生细菌与底泥细菌(AS)三个实验组作用下蓝藻颗粒有机物(POM)在黑暗条件下长期(132天)分解过程,监测颗粒态有机碳(POC)、氮(PON)、磷(POP)、硝酸盐(NO_3~–)、磷酸盐(PO_4^(3–))、溶解性有机碳(DOC)等浓度的变化,揭示蓝藻颗粒有机物的分解和营养盐释放规律。结果表明,在整个降解过程中,叶绿素a(Chla)浓度在培养第28天时降低至最低水平,在三个实验组中Chla分解速率随时间的变化而增大,平均分解速率为:(0.15±0.06)mg/(L·d)。而POC,PON,POP的分解大致分为两个阶段,快速分解大都在28天以内,而后为缓慢降解,且分解速率明显低于Chla,平均分解速率分别为(0.03±0.03)mg/(L·d),(0.04±0.05)mg/(L·d),(0.03±0.02)mg/(L·d),且呈现随着时间变化而降低的趋势。三者之间及其在三个实验组之间的分解速率并无显著性差异。A、AF、AS三个实验组中,POC的最大分解量分别为82.30%、81.90%、63.14%;PON的最大分解量分别为92.85%、91.68%、73.27%;POP的最大分解量分别为93.50%、91.25%、70.11%,表明了POC的转化量小于PON和POP,AS实验组中POM的分解量最低,说明了底泥微生物对藻源有机物具有较低的分解量。此外,随着藻源有机物的降解,水体中NO_3~–、PO_4^(3–)、DOC的最大值出现在Chla完全降解之后,分别是初始值的2.36倍、2.13倍、2.64倍,说明了藻源颗粒有机物的分解将显著增加水体中的营养盐。Cyanobacterial blooms introduce plenty of organic matters to eutrophic lakes,and degradation of these organic matters greatly affects the circulation of nutrients in the water body.In this study,a long-term(132days)degradation process of particulate organic matter(POM)derived from bloom-forming cyanobacteria was simulated under dark conditions in laboratory.The contribution of three bacterial communities to the processes,including cyanobacteria attached bacteria(A),combined effect of attached bacteria and free living bacteria(AF),and combined effect of attached bacteria and sediment bacteria(AS),were investigated.Changes in concentrations of particulate organic carbon(POC),particulate organic nitrogen(PON),particulate organic phosphorus(POP),nitrate(NO3-),phosphate(PO43-)and dissolved organic carbon(DOC)were monitored to reveal the pattern of POM decomposition and nutrient release.The results showed that during the entire degradation process,the concentration of Chla reduced below detection at the28th day.Decomposition rate of Chla increased with time in all the three experimental groups,with an average of(0.15±0.06)mg/(L·d).However,the decomposition of POC,PON and POP roughly divided into two phases including the rapid decomposition stage mostly within28days,and then the slow decomposition phase.The average decomposition rate of POC,PON and POP decreased during the entire process,and was(0.03±0.03)mg/(L·d),(0.04±0.05)mg/(L·d)and(0.03±0.02)mg/(L·d),respectively.They were not significantly different from each treatment,and also not different among the three experimental groups.The maximum release amount of POC in the three experimental groups A,AF,AS was82.30%,81.90%and63.14%;that of PON was92.85%,91.68%and73.27%;and that of PP was:93.50%,91.25%and70.11%respectively.It indicated that the AS experimental group had the lowest POM release,and the amount of POC release was less than PON and POP.These results illustrated that sediment bacteria might contribute more to POM degradation.In addition,along with degr

关 键 词：蓝藻水华 微生物 分解 营养盐 太湖 

分 类 号：X524[环境科学与工程—环境工程]