[Driving Factors Analyze of Phytoplankton Community by Comparison of Population and Functional Groups and Water Quality Evaluation in Dongting Lake].

Phytoplankton is the most important component of water ecosystems, which could indicate the state of the water environment owing to its sensitivity to water environment variation. However, its response to the environment is influenced by classification methods. To understand the phytoplankton population(phyla and genera) and functional groups(FG) for driving response characteristics and applicability to the environment in Dongting Lake, a total of four samples were collected from the lake from March to December 2019, and the distribution characteristics of the phytoplankton population and functional groups and their responses to environmental factors were compared and analyzed.

Effects of Summer and Autumn Drought on Eutrophication and the Phytoplankton Community in Dongting Lake in 2022.

Since July 2022, the Yangtze River basin has experienced the most severe hydro-meteorological drought since record collection started in 1961, which has greatly affected the ecological environment of the Dongting Lake (DTL) basin. To investigate the effects of drought events on the eutrophication and phytoplankton community structure of DTL, the lake was sampled twice in August and September 2022 based on the water level fluctuations resulting in 47 samples. Furthermore, we combined the comprehensive trophic level index (TLI) and phytoplankton Shannon-Wiener diversity index () to characterize and evaluate the eutrophication status.

Nitrogen removal and microbial mechanisms in a novel tubular bioreactor-enhanced floating treatment wetland for the treatment of high nitrate river water.

A novel tubular bioreactor-enhanced floating treatment wetland (TB-EFTW) was developed for the in situ treatment of high nitrate river water. When compared with the enhanced floating treatment wetland (EFTW), the TB-EFTW system achieved 30% higher total nitrogen removal efficiency. Further, the average TN level of the TB-EFTW effluent was below the Grade IV requirement (1.

Quantitative characterization and genetic diversity associated with N-cycle pathways in urban rivers with different remediation techniques.

The nitrate reduction contributions of denitrification, anaerobic ammonium oxidation (anammox) and dissimilatory nitrate reduction to ammonium (DNRA) remain largely unknown especially in the context of river remediation. In this research, the quantitative differentiation of these three nitrate-reduction processes with different remediation conditions was done by the joint use of microbial analysis and nitrogen isotope-tracing. The experiments were done in simulated river systems with 100-day operations.

The coupling of mixotrophic denitrification, dissimilatory nitrate reduction to ammonium (DNRA) and anaerobic ammonium oxidation (anammox) promoting the start-up of anammox by addition of calcium nitrate.

This study discovered one nitrate-calcium-based anammox start-up pathway. Compared with control, the start-up time of anammox was saved by 33.3%, and the average total nitrogen removal efficiency increased from 29.

Effects of design parameters, microbial community and nitrogen removal on the field-scale multi-pond constructed wetlands.

Ecological multi-pond constructed wetlands (CWs) are an alternative wastewater treatment technology for nitrogen removal from non-point source pollution. As an important component of nitrogen cycles in the field-scale CWs, microorganisms are affected by design parameters. Nevertheless, the mechanism of design parameters affecting the distribution of microbial community and removal performance remains largely unexplored.

Feasibility of iron scraps for enhancing nitrification of domestic wastewater at low temperatures.

The development of an effective approach to improve low-temperature nitrification of domestic wastewater remains an important issue that needs to be urgently addressed. This study was intended to verify the feasibility of using iron scraps as an effective immobilization material to enhance nitrification activity in domestic wastewater-treatment systems at low temperatures. Iron scraps were tried and compared with one common immobilization material (PVA-SA embedded balls) in terms of low-temperature nitrification performances, anti-shock capacity, dynamics of microbial community, and economic costs.

Calcium nitrate as a bio-stimulant for anaerobic ammonium oxidation process.

This study explored the role of calcium nitrate as a bio-stimulant for anaerobic ammonium oxidation (anammox) process. The anaerobic sequencing batch reactor was firstly inoculated with malodorous river sediment and only fed with calcium nitrate until no marked endogenous release of ammonium in effluent (Phase 1). Subsequently, nitrite and ammonium were supplied to test the performance of anammox process (Phase 2).

Coagulation-flocculation: a potential application for mosquito Larval Source Management (LSM).

Larval mosquitoes have a more limited home range and lower resistance to adverse environment than adults, thus can be ideal targets for vector control in some cases. Coagulation-flocculation technology, which could be used for water treatment in breeding sites of several vector mosquito species, can significantly change both the distribution of organic particles and surface sediment characteristics in water environment. The aim of this study was to explore the effect, principle and possibility of using coagulation-flocculation technology in immature mosquitoes killing.

Responses of Ammonia-Oxidizing Archaea and Bacteria in Malodorous River Sediments to Different Remediation Techniques.

In this study, the joint use of high throughput sequencing, real-time quantitative PCR, and ammonia-oxidizing bacteria (AOB)-inhibiting allylthiourea was used to differentiate between the contributions of ammonia-oxidizing archaea (AOA) vs AOB to ammonia oxidation and ascertain how AOA and AOB responded to two widely used river remediation techniques (aeration and Ca(NO) injection). Results showed that ammonia oxidation was largely attributed to ATU-sensitive AOB rather than AOA and Nitrosomonas was the predominant AOB-related genus (53.86%) in the malodorous river.

Effects of exposure to anionic surfactants (SDBS and SDS) on nitrogen removal of aerobic denitrifier.

In order to explain the effect of anionic surfactants on aerobic denitrification in the urban river, sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl sulfonate (SDS) were added in aerobic denitrifier and the efficiency of nitrogen removal, microbial mechanisms, and enzyme activity was investigated in this study. The results showed that the total nitrogen (TN) and the nitrate nitrogen ( ) removal efficiency decreased as an increase of SDBS concentration. In contrast, 59.

Dynamics of nitrogen transformation and bacterial community with different aeration depths in malodorous river.

In this research, the dynamics of nitrogen transformation and bacterial community in malodorous river were investigated with different aeration depths. Computational flow dynamics (CFD) and Reynolds number (Re) were specially used to characterize the hydrodynamics condition under different aeration depths. The results indicated that aeration depth had vital impact on nitrogen transformation and bacterial community structure.

Multiphasic assessment of effects of design configuration on nutrient removal in storing multiple-pond constructed wetlands.

As an important technology for purifying and recycling agricultural wastewater, storing multiple-pond constructed wetlands (SMCWs) are widely used in the treatment of non-point source pollution. However, the influences of design configuration (surface area, volume, flow path, aspect ratio, water depth, percent vegetation cover and planting pattern) on pollution mitigation in SMCWs are still underexplored. To improve the sustainability of constructed wetlands, the removal performances of four groups of SMCWs were assessed through multiphasic analyses.

A novel pilot-scale tubular bioreactor-enhanced floating treatment wetland for efficient in situ nitrogen removal from urban landscape water: Long-term performance and microbial mechanisms.

In order to strengthen in situ nitrogen removal of urban landscape water, a novel pilot-scale tubular bioreactor-enhanced floating treatment wetland (TB-EFTW) was constructed, and the long-term performance and responsible microbial mechanisms were investigated in this study. The results showed that the system could remove 81.5% nitrogen from the landscape water after 240 days' operation.

Seasonal variations of performance and operation in field-scale storing multipond constructed wetlands for nonpoint source pollution mitigation in a plateau lake basin.

Storing multipond constructed wetlands, dispersed in the areas of rural lake or river basins, are unique and alternative conventional treatment systems for non-point source pollution. However, the sustainable operation and successful application of these systems remain a challenge. This study aimed to assess the seasonal variations of performance, identify operational factors of nutrients removal and fill the knowledge gap of field-scale storing multipond constructed wetlands application in a plateau lake watershed.

Use of multiple water surface flow constructed wetlands for non-point source water pollution control.

Multiple free water surface flow constructed wetlands (multi-FWS CWs) are a variety of conventional water treatment plants for the interception of pollutants. This review encapsulated the characteristics and applications in the field of ecological non-point source water pollution control technology. The roles of in-series design and operation parameters (hydraulic residence time, hydraulic load rate, water depth and aspect ratio, composition of influent, and plant species) for performance intensification were also analyzed, which were crucial to achieve sustainable and effective contaminants removal, especially the retention of nutrient.

Assessment and analysis of aged refuse as ammonium-removal media for the treatment of landfill leachate.

This is the first attempt to explore the sustainability of aged refuse as ammonium-removal media. Batch experiments combined with the aged-refuse-based reactor were performed to examine how the adsorption and desorption processes are involved in the ammonia removal via aged refuse media in this research. The results showed that the adsorption of ammonium by aged refuse occurred instantly and the adsorbed ammonium was stable and less exchangeable.

Screening and optimizing of inhibitors for ammonia-oxidizing bacteria in sediments of malodorous river.

The proper use of selective ammonia-oxidizing archaea (AOA) and/or ammonia-oxidizing bacteria (AOB) inhibitors is critical to distinguish AOA and AOB contribution. In this research, three inhibitors including ampicillin, dicyandiamide (DCD), and allylthiourea (ATU) were examined mainly focusing on inhibiting dosage, adaptability, and effects. The results showed that the optimized inhibitory dosage of ampicillin, DCD, and ATU was separately 1.

Impact of aeration disturbances on endogenous phosphorus fractions and their algae growth potential from malodorous river sediment.

The present work assessed the impact of aeration disturbances on sediment-bound phosphorus fractions and their algae growth potential from a typical malodorous river. Phosphorus was sequentially extracted by a modified version of Hedley fractionation method. It was found that the mean contents of TP was 1476.

Biomineralization in metakaolin modified cement mortar to improve its strength with lowered cement content.

The role of industrial byproduct as supplementary cementitious material to partially replace cement has greatly contributed to sustainable environment. Metakaolin (MK), one of such byproduct, is widely used to partial replacement of cement; however, during cement replacement at high percentage, it may not be a good choice to improve the strength of concrete. Thus, in the present study, biocement, a product of microbially induced carbonate precipitation is utilized in MK-modified cement mortars to improve its compressive strength.

The large-scale process of microbial carbonate precipitation for nickel remediation from an industrial soil.

Microbial carbonate precipitation is known as an efficient process for the remediation of heavy metals from contaminated soils. In the present study, a urease positive bacterial isolate, identified as Bacillus cereus NS4 through 16S rDNA sequencing, was utilized on a large scale to remove nickel from industrial soil contaminated by the battery industry. The soil was highly contaminated with an initial total nickel concentration of approximately 900 mg kg.

[Research on Remediation of Heavy Metals in Sediment with Lotus and Water Lily].

The aquatic landscape plants lotus and water lily were selected to repair the heavy metal in black odorous river sediments. With ICP-AES inductively coupled full spectrum of direct reading plasma emission spectrometry, the total and forms of content of heavy metals Cd, Cr, Cu, Ni, Pb in sediment and plants, the distribution of heavy metals in plants to were determined .The results showed that the average removal rate of the lotus in terms of the removal of heavy metals in the sediments was 20.

Abundance and distribution of immature mosquitoes in urban rivers proximate to their larval habitats.

Whether ecological restoration of polluted urban rivers would provide suitable breeding habitats for some mosquitoes was not clear yet. It was therefore important to determine how altered river conditions influence mosquito ecology. Monthly data on water quality and larval density were obtained to determine the effects of river systems on the distribution and abundance of immature mosquitoes in two coastal cities in Eastern China.