Corrigendum to “Contribution of bedrock dip angle impact to nitrogen and phosphorus leakage loss under artificial rainfall simulations on slopes parallel to and perpendicular to the bedrock dip in a karst trough valley” [Catena 196 (2021) 104884]

Abstract Stormwater runoff is identified as a major source of pollution in water bodies, and to limit the impact of these pollutants on groundwater quality, permeable asphalt pavement systems (PAPS) have been built worldwide. But so far, few have considered zeolite or regulated zeolite as a post-treatment in reservoirs in PAPS. This study aimed at investigating the efficiencies of modified zeolites in removing NH4+-N and TP from stormwater runoff and providing a novel insight into the research on the reuse of stormwater runoff by PAPS. The effect of PAPS with a zeolite-regulated reservoir on removing nutrient in stormwater was explored by artificial rainfall experiments and temporary storage experiments. Results showed that the removal rate of NH4+-N and TP in PAPS with a regulated-zeolite reservoir increased by 23.7% and 37.2%, respectively, during simulated rainfall events when compared to those without a regulated-zeolite reservoir. TP was mainly removed by the form of phosphorus precipitation such as Zr(H2PO4)2. Ion exchange and adsorption during the temporary storage period were considered as the main approaches for removal of NH4+-N and TP. This study can help develop an optimal strategy for the operation of PAPS in treating stormwater runoff from urban roads.

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Nutrient leaching from extensive green roofs with different substrate compositions: a laboratory study

Water Science & Technology ◽

10.2166/wst.2017.622 ◽

2017 ◽

Vol 77 (4) ◽

pp. 1007-1014 ◽

Cited By ~ 2

Author(s):

Wei Zhang ◽

Xing Zhong ◽

Wu Che

Keyword(s):

Peat Soil ◽

Green Roof ◽

Green Roofs ◽

Nutrient Leaching ◽

Nitrogen And Phosphorus ◽

Cumulative Emission ◽

Term Operation ◽

Artificial Rainfall ◽

The Difference ◽

Extensive Green Roofs

Abstract To investigate nutrient leaching from extensive green roofs, green roof platforms were established to investigate the effluent quantity and quality during artificial rainfall. When the influent volume reached three times the empty bed volume, for which the cumulative rainfall was around 300 mm, the effluent TP and COD concentrations of green roof platforms filled with peat soil did not tend to stabilize. For a long-term operation, the substrate depths had little significant influence on TN, TP and COD concentrations of the green roof effluents. A normalized cumulative emission process method was proposed to discuss the difference in various pollutant leaching processes. Obvious differences in the leaching process of different contaminants for green roof platforms filled with various substrates were observed. For the green roof filled with modified substrates, the nitrogen and phosphorus pollutant leaching rates were relatively high in the initial stage of green roof operation and the phosphorus leaching rate was higher than that of nitrogen. The green roof is a sink for TN, but not for TP and COD in this study. The outcomes are critical for the selection of green roof substrates and also contribute to green roof maintenance.

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Study of the Leakage Loss in a Silica-on-Silicon Slab Waveguide

Fiber & Integrated Optics ◽

10.1080/01468030303817 ◽

2003 ◽

Vol 22 (4) ◽

pp. 249-261 ◽

Cited By ~ 1

Author(s):

JUN LU ◽

SAILING HE ◽

VLADIMIR ROMANOV

Keyword(s):

Slab Waveguide ◽

Leakage Loss ◽

Silicon Slab

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Influence of increased nutrient supply on Microcystis aeruginosa at cellular and proteomic levels

Aquatic Microbial Ecology ◽

10.3354/ame01939 ◽

2020 ◽

Vol 85 ◽

pp. 47-58

Author(s):

Y Jiang ◽

Y Liu

Keyword(s):

Microcystis Aeruginosa ◽

Regulatory Protein ◽

Acid Synthesis ◽

Nutrient Supply ◽

Nitrogen Supply ◽

Nitrogen And Phosphorus ◽

Comprehensive Description ◽

Amino Acid Synthesis ◽

High Nutrient ◽

Proteomic Responses

Various studies have observed that increased nutrient supply promotes the growth of bloom-forming cyanobacteria, but only a limited number of studies have investigated the influence of increased nutrient supply on bloom-forming cyanobacteria at the proteomic level. We investigated the cellular and proteomic responses of Microcystis aeruginosa to elevated nitrogen and phosphorus supply. Increased supply of both nutrients significantly promoted the growth of M. aeruginosa and the synthesis of chlorophyll a, protein, and microcystins. The release of microcystins and the synthesis of polysaccharides negatively correlated with the growth of M. aeruginosa under high nutrient levels. Overexpressed proteins related to photosynthesis, and amino acid synthesis, were responsible for the stimulatory effects of increased nutrient supply in M. aeruginosa. Increased nitrogen supply directly promoted cyanobacterial growth by inducing the overexpression of the cell division regulatory protein FtsZ. NtcA, that regulates gene transcription related to both nitrogen assimilation and microcystin synthesis, was overexpressed under the high nitrogen condition, which consequently induced overexpression of 2 microcystin synthetases (McyC and McyF) and promoted microcystin synthesis. Elevated nitrogen supply induced the overexpression of proteins involved in gas vesicle organization (GvpC and GvpW), which may increase the buoyancy of M. aeruginosa. Increased phosphorus level indirectly affected growth and the synthesis of cellular substances in M. aeruginosa through the mediation of differentially expressed proteins related to carbon and phosphorus metabolism. This study provides a comprehensive description of changes in the proteome of M. aeruginosa in response to an increased supply of 2 key nutrients.

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Method application of optimal multi-parameter analysis to assess the distribution of water masses as an example of CTD data of the Barents Sea in summer 2017

Hydrosphere Еcology (Экология гидросферы) ◽

10.33624/2587-9367-2019-2(4)-38-51 ◽

2019 ◽

pp. 38-51

Author(s):

Valeriy G. Yakubenko ◽

Anna L. Chultsova

Keyword(s):

Barents Sea ◽

Field Measurements ◽

Structural Similarity ◽

Water Masses ◽

Parameter Analysis ◽

Water Dynamics ◽

Phosphorus Concentration ◽

Nitrogen And Phosphorus ◽

The Barents Sea ◽

Expert Assessments

Identification of water masses in areas with complex water dynamics is a complex task, which is usually solved by the method of expert assessments. In this paper, it is proposed to use a formal procedure based on the application of the method of optimal multiparametric analysis (OMP analysis). The data of field measurements obtained in the 68th cruise of the R/V “Academician Mstislav Keldysh” in the summer of 2017 in the Barents Sea on the distribution of temperature, salinity, oxygen, silicates, nitrogen, and phosphorus concentration are used as a data for research. A comparison of the results with data on the distribution of water masses in literature based on expert assessments (Oziel et al., 2017), allows us to conclude about their close structural similarity. Some differences are related to spatial and temporal shifts of measurements. This indicates the feasibility of using the OMP analysis technique in oceanological studies to obtain quantitative data on the spatial distribution of different water masses.

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Failure Analysis Of Buried Gas Pipelines Crossing Seismic Faults

Academic Perspective Procedia ◽

10.33793/acperpro.03.02.2 ◽

2020 ◽

Vol 3 (2) ◽

pp. 781-790

Author(s):

M. Rizwan Akram ◽

Ali Yesilyurt ◽

A.Can. Zulfikar ◽

F. Göktepe

Keyword(s):

Ground Deformation ◽

Warning System ◽

Strike Slip ◽

Gas Pipelines ◽

Steel Pipes ◽

Seismic Fault ◽

Fault Parameters ◽

Dip Angle ◽

Permanent Ground Deformation ◽

Recent Earthquakes

Research on buried gas pipelines (BGPs) has taken an important consideration due to their failures in recent earthquakes. In permanent ground deformation (PGD) hazards, seismic faults are considered as one of the major causes of BGPs failure due to accumulation of impermissible tensile strains. In current research, four steel pipes such as X-42, X-52, X-60, and X-70 grades crossing through strike-slip, normal and reverse seismic faults have been investigated. Firstly, failure of BGPs due to change in soil-pipe parameters have been analyzed. Later, effects of seismic fault parameters such as change in dip angle and angle between pipe and fault plane are evaluated. Additionally, effects due to changing pipe class levels are also examined. The results of current study reveal that BGPs can resist until earthquake moment magnitude of 7.0 but fails above this limit under the assumed geotechnical properties of current study. In addition, strike-slip fault can trigger early damage in BGPs than normal and reverse faults. In the last stage, an early warning system is proposed based on the current procedure.&nbsp;

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