Effects of Large-Scale Manure Treatment Processes on Pathogen Reduction, Protein Distributions, and Nutrient Concentrations

One of the most critical variables in microalgae-related processes is the pH; it directly determines the overall performance of the production system especially when coupling with wastewater treatment. In microalgae-related wastewater treatment processes, the adequacy of pH has a large impact on the microalgae/bacteria consortium already developing on these systems. For cost-saving reasons, the pH is usually controlled by classical On/Off control algorithms during the daytime period, typically with the dynamics of the system and disturbances not being considered in the design of the control system. This paper presents the modelling and pH control in open photobioreactors, both raceway and thin-layer, using advanced controllers. In both types of photobioreactors, a classic control was implemented and compared with a Proportional–Integral (PI) control, also the operation during only the daylight period and complete daily time was evaluated. Thus, three major variables already studied include (i) the type of reactors (thin-layers and raceways), (ii) the type of control algorithm (On/Off and PI), and (iii) the control period (during the daytime and throughout the daytime and nighttime). Results show that the pH was adequately controlled in both photobioreactors, although each type requires different control algorithms, the pH control being largely improved when using PI controllers, with the controllers allowing us to reduce the total costs of the process with the reduction of CO2 injections. Moreover, the control during the complete daily cycle (including night) not only not increases the amount of CO2 to be injected, otherwise reducing it, but also improves the overall performance of the production process. Optimal pH control systems here developed are highly useful to develop robust large-scale microalgae-related wastewater treatment processes.

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Microbial’s Effects on Invasive Grass’ Response to Water and Nutrient Stress

10.21203/rs.3.rs-117418/v1 ◽

2020 ◽

Author(s):

Bo Zhang ◽

Yingdan Yuan ◽

Karolina M. Pajerowska-Mukhtar ◽

Michelle Afkhami ◽

Alan Hastings ◽

...

Keyword(s):

Large Scale ◽

Interactive Effect ◽

Invasion Biology ◽

Imperata Cylindrica ◽

Invasion Success ◽

Nutrient Concentrations ◽

Sequencing Analysis ◽

Drought Treatment ◽

Plant Microbe Interaction ◽

Invasion Mechanisms

Abstract Background Soil microbiomes play important roles in invasion biology, yet it is often treated as a ‘black box’ in modeling or large-scale field studies. Hence, investigating the change of association between invasive vegetation and soil microbes under changing environmental conditions, and exploring the genetic functions of associated microbiomes will provide a deeper understanding of invasion mechanisms. We performed a microcosm experiment with cogongrass (Imperata cylindrica (L.) P. Beauv.), which is one of the 100 worst invasive plants in the world. We combined rigorous sequencing analysis, including 16S rRNA, ITS, and shotgun metagenome sequencing, for the first time, to investigate the interactive effect of change in soil water and nutrient concentrations on microbiomes diversity, composition and genetic functions under invasion. Results We found that experimental drought has a stronger effect on the bacterial community than the fungal community. We discovered an enrichment of microbial groups, including Proteobacteria, Actinobacteria, Bacteroidetes and Chloroflexi under drought treatment, could likely contribute to invasion success. Further, we showed a striking trend of induction of cell wall, membrane and desiccation-related genes in drought treatment and a marked downregulation in regular treatment, which could create a more hydrated microenvironment, facilitating biofilm formation and better protection from desiccation.Conclusions Our work contributes to highlighting the associated microbial communities may have a potential long-term impact on increasing cogongrass drought resistance, ultimately, future invasion might be severe due to the plant-microbe interaction. These findings are important because current modeling practice, lacking comprehensive consideration of the plant-microbe interaction, could lead to a significant underestimate of predictions of future invasion patterns.

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Modelling the biogeochemical effects of heterotrophic and autotrophic N<sub>2</sub> fixation in the Gulf of Aqaba (Israel), Red Sea

Biogeosciences ◽

10.5194/bg-15-7379-2018 ◽

2018 ◽

Vol 15 (24) ◽

pp. 7379-7401 ◽

Cited By ~ 2

Author(s):

Angela M. Kuhn ◽

Katja Fennel ◽

Ilana Berman-Frank

Keyword(s):

Water Column ◽

Red Sea ◽

N2 Fixation ◽

Large Scale ◽

Gulf Of Aqaba ◽

Nutrient Concentrations ◽

Nutrient Ratios ◽

Biogeochemical Models ◽

Deep Waters ◽

Direct Measurements

Abstract. Recent studies demonstrate that marine N2 fixation can be carried out without light by heterotrophic N2 fixers (diazotrophs). However, direct measurements of N2 fixation in aphotic environments are relatively scarce. Heterotrophic as well as unicellular and colonial photoautotrophic diazotrophs are present in the oligotrophic Gulf of Aqaba (northern Red Sea). This study evaluates the relative importance of these different diazotrophs by combining biogeochemical models with time series measurements at a 700 m deep monitoring station in the Gulf of Aqaba. At this location, an excess of nitrate, relative to phosphate, is present throughout most of the water column and especially in deep waters during stratified conditions. A relative excess of phosphate occurs only at the water surface during nutrient-starved conditions in summer. We show that a model without N2 fixation can replicate the observed surface chlorophyll but fails to accurately simulate inorganic nutrient concentrations throughout the water column. Models with N2 fixation improve simulated deep nitrate by enriching sinking organic matter in nitrogen, suggesting that N2 fixation is necessary to explain the observations. The observed vertical structure of nutrient ratios and oxygen is reproduced best with a model that includes heterotrophic as well as colonial and unicellular autotrophic diazotrophs. These results suggest that heterotrophic N2 fixation contributes to the observed excess nitrogen in deep water at this location. If heterotrophic diazotrophs are generally present in oligotrophic ocean regions, their consideration would increase current estimates of global N2 fixation and may require explicit representation in large-scale models.

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A review of current and developing potable water treatment processes

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1243/09544080360562945 ◽

2003 ◽

Vol 217 (1) ◽

pp. 11-23 ◽

Cited By ~ 5

Author(s):

D G Stevenson

Keyword(s):

Water Treatment ◽

Large Scale ◽

Potable Water ◽

Regulatory Requirements ◽

Treatment Technology ◽

The Past ◽

Treatment Processes ◽

The United Kingdom ◽

Scale Of Operation ◽

Potable Water Treatment

The changes in water treatment technology that have occurred within the United Kingdom over the past 25–30 years, together with the present direction of development, are reviewed. Water treatment for public supply differs from many other process technologies, notably in the large scale of operation, the longevity of the plant, the regulatory environment and the slow rate at which new processes can be introduced. Thus, many developments are initiated as a result of regulatory requirements rather than economic factors. Reliability is paramount, and this leads to mechanical simplicity.

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The Mediterranean Sea system: a review and an introduction to the special issue

Ocean Science ◽

10.5194/os-9-789-2013 ◽

2013 ◽

Vol 9 (5) ◽

pp. 789-803 ◽

Cited By ~ 81

Author(s):

T. Tanhua ◽

D. Hainbucher ◽

K. Schroeder ◽

V. Cardin ◽

M. Álvarez ◽

...

Keyword(s):

Mediterranean Sea ◽

Large Scale ◽

Chemical Properties ◽

Short Review ◽

Background Information ◽

Nutrient Concentrations ◽

Special Issue ◽

Ocean Science ◽

The Mediterranean ◽

Biogeochemical Parameters

Abstract. The Mediterranean Sea is a semi-enclosed sea characterized by high salinities, temperatures and densities. The net evaporation exceeds the precipitation, driving an anti-estuarine circulation through the Strait of Gibraltar, contributing to very low nutrient concentrations. The Mediterranean Sea has an active overturning circulation, one shallow cell that communicates directly with the Atlantic Ocean, and two deep overturning cells, one in each of the two main basins. It is surrounded by populated areas and is thus sensitive to anthropogenic forcing. Several dramatic changes in the oceanographic and biogeochemical conditions have been observed during the past several decades, emphasizing the need to better monitor and understand the changing conditions and their drivers. During 2011 three oceanographic cruises were conducted in a coordinated fashion in order to produce baseline data of important physical and biogeochemical parameters that can be compared to historic data and be used as reference for future observational campaigns. In this article we provide information on the Mediterranean Sea oceanographic situation, and present a short review that will serve as background information for the special issue in Ocean Science on "Physical, chemical and biological oceanography of the Mediterranean Sea". An important contribution of this article is the set of figures showing the large-scale distributions of physical and chemical properties along the full length of the Mediterranean Sea.

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A Research Method for Semi-Automated Large-Scale Cultivation of Maize to Full Maturity in an Artificial Environment

Agronomy ◽

10.3390/agronomy11101898 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1898

Author(s):

Matthew Wiethorn ◽

Chad Penn ◽

James Camberato

Keyword(s):

Light Intensity ◽

Large Scale ◽

Maize Yield ◽

Nutrient Concentrations ◽

Shoot Biomass ◽

Plant Responses ◽

Precise Control ◽

Advantages And Disadvantages ◽

Artificial Environment ◽

Maize Plants

There are unique advantages and disadvantages to using the field, greenhouse, growth chamber, and media-less techniques for growing maize (Zea mays L.) for research purposes. Soil-buffered nutrients such as phosphorus (P) do not allow for precise control of solution concentrations in the field, while greenhouses, growth chambers, and hydroponics provide limiting conditions. The objectives of this study were to develop a practical technique for productively cultivating several maize plants from seed to physiological maturity (R6) in a grow room environment, with precise control of nutrient availability and timing, and evaluate its utility for the purpose of measuring plant responses to variations in nutrient concentrations. The construction and testing of a semi-automated grow room for conducting nutrient studies on 96 maize plants utilizing simulated or artificial conditions are described. Plant growth response to a range of solution phosphorus (P) concentrations was tested to evaluate the utility of the technique. Maize yield components were measured and compared to values for field-grown plants. Due to ideal conditions and successful simulation of light intensity, diurnal fluctuations in temperature and RH, and changing photoperiod, grain yield and tissue nutrient concentrations were comparable to field-grown maize, although with greater shoot biomass. Plants responded positively to increased P concentrations in fertigation. The technique can be used for large-scale plant nutrient studies that require precise control of bioavailability and timing as well as manipulation of light intensity and photoperiod duration.

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Nutrient Pollutants in Surface Water—Assessing Trends in Drinking Water Resource Quality for a Regional City in Central Europe

Sustainability ◽

10.3390/su11071988 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1988 ◽

Cited By ~ 1

Author(s):

Włodzimierz Kanownik ◽

Agnieszka Policht-Latawiec ◽

Wioletta Fudała

Keyword(s):

Surface Water ◽

River Water ◽

Water Resource ◽

Water Resource Management ◽

Control Point ◽

Ammonium Nitrogen ◽

Nutrient Concentrations ◽

The European Union ◽

Treatment Processes ◽

Kjeldahl Nitrogen

This paper presents the changes in concentration of seven biogenic indices in the Wisłok River water and determines the water treatment processes required in order to obtain water fit for consumption. The investigations were conducted during 2004–2013, and water samples were collected at a measuring-control point was situated at 67.9 km on the river at the surface water intake for the water supply to the Rzeszów city dwellers. Analysis of the research results allows for the forecasting of technological and organizational changes in the treatment processes of the abstracted water. It was found that only the mean concentration of Kjeldahl nitrogen exceeded the value admissible for class I, which allowed the Wisłok River water to be classified as class II with good potential and determined the water quality category as A2, which indicates the necessity for typical performance physical and chemical treatment. Downward trends in the contents of the tested nutrients occurred during the period of investigation, except for nitrite nitrogen. Statistically significant downward trends were registered for ammonium nitrogen, Kjeldahl nitrogen, total nitrogen and phosphates. The decline in nutrient concentrations in the water of Wisłok is a tangible result of the introduction of new standards of water resource management in the catchment, compliant with the European Union legislation.

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Modelling of full-scale wastewater treatment plants with different treatment processes using the Activated Sludge Model no. 3

Water Science & Technology ◽

10.2166/wst.2001.0012 ◽

2001 ◽

Vol 44 (1) ◽

pp. 49-56 ◽

Cited By ~ 7

Author(s):

M. Wichern ◽

F. Obenaus ◽

P. Wulf ◽

K.-H. Rosenwinkel

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Phosphorus Removal ◽

Large Scale ◽

Wastewater Treatment Plants ◽

Biological Phosphorus Removal ◽

Activated Sludge Model ◽

Treatment Processes ◽

Biological Phosphorus ◽

P Removal

In 1999 the Activated Sludge Model no. 3 (ASM 3) by the IWA task Group on Mathematical Modeling for Design and Operation of Biological Wastewater Treatment was presented. The model is used for simulation of nitrogen removal. On the basis of a new calibration of the ASM 3 with the easy degradable COD measured by respiration simulation runs of this paper have been done. In 2000 a biological phosphorus removal module by the EAWAG was added to the calibrated version of ASM 3 and is now serving the current requirements for modelling the enhanced biological P-removal. Only little experiences with different load situations of large-scale wastewater treatment plants were made with both new models so far. This article reports the experiences with the simulation and calibration of the biological parameters using ASM 3 and the EAWAG BioP Module. Three different large-scale wastewater treatment plants in Germany with different treatment systems will be discussed (Koblenz: pre-denitrification; Hildesheim: simultaneous denitrification with EBPR; Duderstadt: intermediate denitrification with EBPR). Informations regarding the choice of kinetic and stoichiometric parameters will be given.

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