More Like this

1. The fate and removal of pharmaceuticals and personal care products within wastewater treatment facilities discharging to the Great Bay Estuary

   https://doi.org/10.1002/wer.1680  

   Hidrovo, Alexandria ; Luek, Jenna L. ; Antonellis, Carmela ; Malley, Jr., James P. ; Mouser, Paula J. ( January 2022 , Water Environment Research)

   Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that derive primarily in the water environment from combined sewer overflows and discharges from industrial and municipal wastewater treatment facilities (WWTFs). Due to incomplete removal during wastewater treatment, PPCP impacts to aquatic ecosystems are a major concern. The Great Bay Estuary (New Hampshire, USA) is an important ecological, commercial, and recreational resource where upstream WWTFs have recently been under pressure to reduce nitrogen loading to the estuary and consequently upgrade treatment systems. Therefore, we investigated the distribution and abundance of 18 PPCPs and three flame retardants within the Great Bay Estuary and WWTFs discharging to the estuary to examine how WWTF type influenced PPCP removal. All 21 analytes were frequently detected at μg/L to ng/L concentrations in influent and effluent and ng/kg in sludge. WWTFs with enhanced nutrient removal and longer solids retention times correlated to higher PPCP removal, indicating facility upgrades may have benefits related to PPCP removal. Understanding PPCP fate during treatment and in downstream waters informs our ability to assess the environmental and ecological impacts of PPCPs on estuarine resources and develop mitigation strategies to better protect marine ecosystems from emerging contaminant exposure.

   PPCP removal positively correlated with solids retention time and varied by treatment facility and compound.

   Upgrade of WWTFs for biological nitrogen removal may also increase PPCP removal.

   Surface water fluoxetine concentrations may present an ecological risk to the Great Bay Estuary.

    

   more » « less
2. Case study: Bioaugmenting the comammox dominated biomass from B‐stage to enhance nitrification in A‐stage at Blue Plains AWWTP

   https://doi.org/10.1002/wer.11005  

   Nguyen Quoc, Bao ; Peng, Bo ; De Clippeleir, Haydee ; Winkler, Mari‐Karoliina H. ( February 2024 , Water Environment Research)

   A comprehensive case study was undertaken at the Blue Plains wastewater treatment plant (WWTP) to explore the bioaugmentation technique of introducing nitrifying sludge into the non‐nitrifying stage over the course of two operational years. This innovative approach involved the return of waste activated sludge (WAS) from the biological nutrient removal (BNR) system to enhance the nitrification in the high carbon removal rate system. Thecompleteammoniaoxidizer (comammox)Nitrospira Nitrosawas identified as the main nitrifier in the system. Bioaugmentation was shown to be successful as nitrifiers returned from BNR were able to increase the nitrifying activity of the high carbon removal rate system. There was a positive correlation between returned sludge from the BNR stage and the specific total kjeldahl nitrogen (TKN) removal rate in A stage. The bioaugmentation process resulted in a remarkable threefold increase in the specific TKN removal rate within the A stage. Result suggested that recycling of WAS is a simple technique to bio‐augment a low SRT system with nitrifiers and add ammonia oxidation to a previously non‐nitrifying stage. The results from this case study hold the potential for applicable implications for other WWTPs that have a similar operational scheme to Blue Plains, allowing them to reuse WAS from the B stage, previously considered waste, to enhance nitrification and thus improving overall nitrogen removal performance.

   Comammox identifying as main nitrifier in the B stage.

   Comammox enriched sludge from B stage successfully bio‐augmented the East side of A stage up to threefold.

   Bioaugmentation of comammox in the West side of A stage was potentially inhibited by the gravity thickened overflow.

   Sludge returned from B stage to A stage can improve nitrification with a very minor retrofits and short startup times.

    

   more » « less
3. Interrogating the performance and microbial ecology of an enhanced biological phosphorus removal/post‐anoxic denitrification process at bench and pilot scales

   https://doi.org/10.1002/wer.10852  

   Coats, Erik R. ; Appel, Felicity J. ; Guho, Nick ; Brinkman, Cynthia K. ; Mellin, Jason ( April 2023 , Water Environment Research)

   Research focused on interrogating post‐anoxic enhanced biological phosphorus removal (EBPR) at bench and pilot scales. Average bench‐scale effluent ranged from 0.33 to 1.4 mgP/L, 0.35 to 3.7 mgNH₃‐N/L, and 1.1 to 3.9 mgNO_x‐N/L. Comparatively, the pilot achieved effluent (50th percentile/average) of 0.13/0.2 mgP/L, 9.7/8.2 mgNH₃‐N/L, and 0.38/3.3 mgNO_x‐N/L under dynamic influent and environmental conditions. For EBPR process monitoring, P:C ratio data indicated that 0.2–0.4 molP/molC will result in stable EBPR; relatedly, a target design influent volatile fatty acid (VFA):P ratio would exceed 15 mgCOD/mgP. Post‐anoxic EBPR was enriched forNitrobacterspp. at 1.70%–20.27%, withParcubacteriaalso dominating; the former is putatively associated with nitritation and the latter is a putative fermenting heterotrophic organism. Post‐anoxic specific denitrification rates (SDNRs) (20°C) ranged from 0.70 to 3.10 mgN/gVSS/h; there was a strong correlation (R² = 0.94) between the SDNR and %Parcubacteriafor systems operated at a 20‐day solids residence time (SRT). These results suggest that carbon substrate potentially generated by this putative fermenter may enhance post‐anoxic EBPR.

   Post‐anoxic EBPR can achieve effluent of <0.2 mgP/L and <12 mgN/L.

   The P:C and VFA:P ratios can be predictive for EBPR process monitoring.

   Post‐anoxic EBPR was enriched forNitrobacterspp. overNitrospiraspp. and also forParcubacteria, which is a putative fermenting heterotrophic organism.

   Post‐anoxic specific denitrification rates (20°C) ranged from 0.70 to 3.10 mgN/gVSS/h.

   BLASTn analysis of 16S rDNA PAO primer set was shown to be improved to 93.8% for Ca. Accumulibacter phosphatis and 73.2%–94.0% for all potential PAOs.

    

   more » « less
4. Sensor‐mediated granular sludge reactor for nitrogen removal and reduced aeration demand using a dilute wastewater

   https://doi.org/10.1002/wer.1296  

   Bekele, Zerihun A. ; Delgado Vela, Jeseth ; Bott, Charles B. ; Love, Nancy G. ( February 2020 , Water Environment Research)

   A sensor‐mediated strategy was applied to a laboratory‐scale granular sludge reactor (GSR) to demonstrate that energy‐efficient inorganic nitrogen removal is possible with a dilute mainstream wastewater. The GSR was fed a dilute wastewater designed to simulate an A‐stage mainstream anaerobic treatment process. DO, pH, and ammonia/nitrate sensors measured water quality as part of a real‐time control strategy that resulted in low‐energy nitrogen removal. At a low COD (0.2 kg m⁻³ day⁻¹) and ammonia (0.1 kg‐N m⁻³ day⁻¹) load, the average degree of ammonia oxidation was 86.2 ± 3.2% and total inorganic nitrogen removal was 56.7 ± 2.9% over the entire reactor operation. Aeration was controlled using a DO setpoint, with and without residual ammonia control. Under both strategies, maintaining a low bulk oxygen level (0.5 mg/L) and alternating aerobic/anoxic cycles resulted in a higher level of nitrite accumulation and supported shortcut inorganic nitrogen removal by suppressing nitrite oxidizing bacteria. Furthermore, coupling a DO setpoint aeration strategy with residual ammonia control resulted in more stable nitritation and improved aeration efficiency. The results show that sensor‐mediated controls, especially coupled with a DO setpoint and residual ammonia controls, are beneficial for maintaining stable aerobic granular sludge.

   Tight sensor‐mediated aeration control is need for better PN/A.

   Low DO intermittent aeration with minimum ammonium residual results in a stable N removal.

   Low DO aeration results in a stable NOB suppression.

   Using sensor‐mediated aeration control in a granular sludge reactor reduces aeration cost.

    

   more » « less
5. A trait‐based approach to assessing resistance and resilience to wildfire in two iconic North American conifers

   https://doi.org/10.1111/1365-2745.13480  

   Rodman, Kyle C. ; Veblen, Thomas T. ; Andrus, Robert A. ; Enright, Neal J. ; Fontaine, Joseph B. ; Gonzalez, Angela D. ; Redmond, Miranda D. ; Wion, Andreas P. ; Battipaglia, ed., Giovanna ( August 2020 , Journal of Ecology)

   Ongoing changes in fire regimes have the potential to drive widespread shifts in Earth's vegetation. Plant traits and vital rates provide insight into vulnerability to fire‐driven vegetation shifts because they can be indicators of the ability of individuals to survive fire (resistance) and populations to persist (resilience) following fire.

   In 15 study sites spanning climatic gradients in the southern Rocky Mountains, USA, we quantified variation in key traits and vital rates of two co‐occurring, widely distributed conifers (Pinus ponderosaDouglas ex. P. Lawson & C. Lawson andPseudotsuga menziesii(Mirb.) Franco). We used mixed‐effects models to explain inter‐ and intraspecific variation in tree growth, survival, bark thickness and seed cone production, as a function of species, tree life stage (i.e. diameter, height and age), average climate, local competition and site conditions.

   Pinus ponderosawas predicted to survive low‐severity fire at a 23% earlier age thanP. menziesii.Pinus ponderosahad thicker bark and more rapid juvenile height growth, traits conferring greater fire resistance. In contrast,P. menziesiiwas predicted to produce seed cones at a 28% earlier age thanP. ponderosa. For both species, larger individuals were more likely to survive fire and to produce cones. ForP. ponderosa, cone production increased where average actual evapotranspiration (AET) was higher and local competition was lower. More frequent cone production on productive sites with higher AET is an important and underappreciated mechanism that may help to explain greater resilience to fire in these areas.

   Synthesis. Our analyses indicated that many plant traits and vital rates related to fire differed betweenPinus ponderosaandPseudotsuga menziesii, with trade‐offs between investment in traits that promote individual defence to fire and those that promote recolonization of disturbed sites. Future changes in fire regimes will act as a filter throughout North American forests, with our findings helping to infer which individuals and populations of two iconic species are most vulnerable to future change and offering a framework for future inquiry in other forests facing an uncertain future.

    

   more » « less