Proceedings 會 刊 - SCCAEPA SPONSORS

Structure dynamics and function of microbial community in a denitrifying dephosphatation
system
YU Ran, and LU Xiwu*
School of Energy and Environment, Southeast University, Sipailou 2#, Nanjing 210096, P.R. China
Abstract: The microbial communities in an anoxic tank of an anaerobic-anoxic/nitrifying (A2N) two sludge
system coupled with induced crystallization (IC) were investigated for denitrifying dephosphatation
process. Similar microbial relative abundance distribution profiles were observed in both the sequencing
batch and continuous flow reaction systems. The phosphorus accumulating organisms (PAOs)
consistently accounted for more than 70% of the eubacterial density with the denitrifying phosphateaccumulating
organisms (DPAOs) identified as the predominant species. The increase of COD to
phosphorus feeding ratios from 18:1 to 63:1 steadily enhanced the phosphorus removal rates, but no
statistically significant effects were observed on the PAO relative abundance. The change of COD to
nitrogen feeding ratio from 5:1 to 6:1 restrained both the phosphorus and nitrogen removal efficiencies,
and the PAOs‟ relative density. The relative density distribution of GAOs mirrored the PAOs distribution,
which revealed the existence of carbon competition between PAOs and glucose accumulating organisms
(GAOs) in the denitrifying dephosphatation system. The Actinobacteria class and the Rhodocyclus genus
were identified as the important DPAOs contributors. The non-comparable abundance distribution profiles
of Actinobacteria, Rhodocyclus, and PAOs hinted that the phylogenetic diversity and the predominant
DPAO density secured the functional stability of denitrifying dephosphatation in the A2N-IC system.
Keywords: denitrifying phosphate-accumulating organisms (DPAOs), phosphorus accumulating
organisms (PAOs), microbial relative density distribution, anaerobic-anoxic/nitrifying/induced
crystallization process (A2N-IC), phosphorus removal.
Research on eco-compensation for water conservation based on WTA: case study of Miyun
Reservoir, China
Linyu Xu 1 Bing Yu 1 Yang Li 1
1 State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of
Environment, Beijing Normal University, No. 19, Xinjiekouwai Street, Haidian District, Beijing, 100875,
China, Email: xly@bnu.edu.cn, yubing-01@163.com
Abstract: Eco-compensation is an effective economic management method for ecological protection and
has been widely used for water resource protection. The determination of eco-compensation standard is
the key issue in eco-compensation research, as it is hard to quantify the variation of stakeholders‟
benefits exactly. For this case, the willingness to accept (WTA) was brought into the accounting system of
eco-compensation standards in this paper, with the case study of Miyun Reservoir conservation area. In
this paper, the econometric models were built based on the contingent valuation questionnaires, and the
influential factors of stakeholders‟ willingness and WTA amount were studied respectively. The results
showed that the average value of Miyun Reservoir residents‟ WTA was about 1700 yuan/family/year.
While, the distance to reservoir, job types, and the cognition of eco-compensation showed significant
effect on their bid values.
Keywords: contingent valuation method;preference analysis; questionnaire survey; Miyun Reservoir
Structure dynamics and function of microbial community in a denitrifying dephosphatation
system
YU Ran 1 , and LU Xiwu 1 *
1. School of Energy and Environment, Southeast University, Sipailou 2#, Nanjing 210096, P.R. China
* Corresponding author, Email: yuran@seu.edu.cn, xiwulu@seu.edu.cn
Abstract:The microbial communities in an anoxic tank of an anaerobic-anoxic/nitrifying (A2N) two sludge
system coupled with induced crystallization (IC) were investigated for denitrifying dephosphatation
process. Similar microbial relative abundance distribution profiles were observed in both the sequencing
batch and continuous flow reaction systems. The phosphorus accumulating organisms (PAOs)
consistently accounted for more than 70% of the eubacterial density with the denitrifying phosphateaccumulating
organisms (DPAOs) identified as the predominant species. The increase of COD to
phosphorus feeding ratios from 18:1 to 63:1 steadily enhanced the phosphorus removal rates, but no
statistically significant effects were observed on the PAO relative abundance. The change of COD to
nitrogen feeding ratio from 5:1 to 6:1 restrained both the phosphorus and nitrogen removal efficiencies,
and the PAOs‟ relative density. The relative density distribution of GAOs mirrored the PAOs distribution,
which revealed the existence of carbon competition between PAOs and glucose accumulating organisms
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