Estimating the Importance of Hydrologic Conditions on Nutrient Retention and Plant Richness in a Wetlaculture Mesocosm Experiment in a Former Lake Erie Basin Swamp

The western basin of Lake Erie, the shallowest of the Laurentian Great Lakes in North America, is now plagued by harmful algal blooms annually due to nutrient discharges primarily from its basin. Water quality was impacted so significantly by toxic cyanobacteria in 2014 that the city of Toledo’s water supply was shut off, affecting hundreds of thousands of residents. A new agricultural land management approach, ‘wetlaculture (=wetland + agriculture)’, has a goal of reducing the need for fertilizer applications while preventing fluxes of nutrients to downstream aquatic ecosystems. A wetlaculture mesocosm experiment was set up on agricultural land near Defiance, Ohio, on the northwestern edge of the former ‘Great Black Swamp’. The mesocosms were randomly assigned to four hydrologic treatments involving two water depths (no standing water and ~10-cm of standing water) and two hydraulic loading rates (10 and 30 cm week−1). Nearby agricultural ditch water was pumped to provide weekly hydraulic loading rates to the mesocosms. During the two-year period, the net mass retention of phosphorus from the water was estimated to have averaged 1.0 g P m−2 in the wetland mesocosms with a higher hydraulic loading rate, while the highest estimated net nitrogen mass retention (average 22 g N m−2) was shown in the wetland mesocosms with 10 cm of standing water and higher hydraulic loading rate. Our finding suggests that hydrologic conditions, especially water level, contribute directly and indirectly to nutrient retention, partially through the quick response of the wetland vegetation community. This study provides valuable information for scaling up to restore significant areas of wetlaculture/wetlands in the former Great Black Swamp, strategically focused on reducing the nutrient loading to western Lake Erie from the Maumee River Basin.

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Coarse filters for pond effluent polishing: comparison of loading rates and grain sizes

Water Science & Technology ◽

10.2166/wst.2007.342 ◽

2007 ◽

Vol 55 (11) ◽

pp. 121-126 ◽

Cited By ~ 1

Author(s):

M. von Sperling ◽

J.G.B. de Andrada ◽

W.R. de Melo Júnior

Keyword(s):

Loading Rate ◽

Uasb Reactor ◽

E Coli ◽

Effluent Quality ◽

Loading Rates ◽

Hydraulic Loading ◽

Grain Sizes ◽

Belo Horizonte ◽

The City ◽

Rock Size

A system comprising a UASB reactor, shallow polishing ponds and shallow coarse filters, treating actual wastewater from the city of Belo Horizonte, Brazil, has been evaluated. The main focus of the research was to compare grain sizes and hydraulic loading rates in the coarse filters. Two filters operating in parallel were investigated, with the following grain sizes: Filter 1: 3 to 10 cm; Filter 2: 8 to 20 cm. Two hydraulic loading rates were tested: 0.5 and 1.0 m3/m3.d. The filter with the lower rock size had a better performance than the filter with the larger rock size in the removal of SS and, as a consequence, BOD and COD. A better performance was obtained with the hydraulic loading rate of 0.5 m3/m3.d, as compared to the rate of 1.0 m3/m3.d. The effluent quality during the period with the lower loading rate was very good for discharge into water bodies or for agricultural reuse (median effluent concentrations from Filter 1: BOD: 20 mg/L; COD: 106 mg/L; SS: 28 mg/L; E. coli: 528 MPN/100 mL).

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Transport effects on hydraulic loading rate and microbial removal performance in biosand filters

Journal of Water and Health ◽

10.2166/wh.2014.167 ◽

2014 ◽

Vol 12 (4) ◽

pp. 686-691 ◽

Cited By ~ 6

Author(s):

Julie Napotnik ◽

Kristen Jellison

Keyword(s):

Loading Rate ◽

E Coli ◽

Loading Rates ◽

Hydraulic Loading ◽

Filter Performance ◽

Implementation Costs ◽

Transport Effects ◽

Biosand Filters ◽

Microbial Removal ◽

Potential Negative Consequence

Biosand filters (BSFs) are increasingly designed using smaller and/or lighter casing material in an effort to reduce logistical requirements and implementation costs. The increased portability of a smaller, lighter design presents a potential negative consequence: the ability to move the installed/operational filter by the homeowner and potentially disturb the system. This study investigated the effects of moving and agitation on filter performance, using mature BSFs which had been in use for over nine months prior to the move. Data were analyzed for four replicate filters of three different filter types: the traditional concrete BSF and two plastic bucket (5-gal and 2-gal, respectively; 5-gal bucket = 18.9-L bucket, 2-gal bucket = 7.6-L bucket) BSFs. Filters were moved approximately 1 km and monitored for hydraulic loading rates (HLRs) and Escherichia coli removal for 8 weeks following the move. Moving the filters resulted in reduced HLRs, likely due to sand compaction, but E. coli removal remained high (log10 removal ≥2.8 for all sizes) and increased significantly as compared to data collected prior to the move. The resulting operational implications of moving BSFs are discussed.

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Influence of hydrologic conditions on nutrient retention, and soil and plant development in a former central Ohio swamp: A wetlaculture mesocosm experiment

Ecological Engineering ◽

10.1016/j.ecoleng.2020.105969 ◽

2020 ◽

Vol 157 ◽

pp. 105969

Author(s):

BingBing Jiang ◽

William J. Mitsch

Keyword(s):

Plant Development ◽

Nutrient Retention ◽

Mesocosm Experiment ◽

Hydrologic Conditions

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Effects of hydraulic loading rate and aeration mode on nitrogen removal and nitrogen functional gene abundances in subsurface wastewater infiltration systems

Water Science & Technology ◽

10.2166/wst.2017.208 ◽

2017 ◽

Vol 76 (1) ◽

pp. 210-218 ◽

Cited By ~ 4

Author(s):

Yafei Sun ◽

Jing Pan ◽

Shiyue Qi ◽

Hexin Fei

Keyword(s):

Nitrogen Removal ◽

Loading Rate ◽

Oxygen Demand ◽

Functional Gene ◽

Intermittent Aeration ◽

Anaerobic Conditions ◽

Loading Rates ◽

Hydraulic Loading ◽

Artificial Aeration ◽

Operation Cost

Matrix dissolved oxygen, nitrogen removal and nitrogen functional gene abundances in two artificial aeration modes, continuous aeration (CA) and intermittent aeration (IA), in subsurface wastewater infiltration systems (SWISs) under different hydraulic loading rates (HLRs) were investigated. Aeration not only successfully created aerobic conditions at 50 cm depth, but also did not change anoxic or anaerobic conditions at 80 and 110 cm depths. Meanwhile, aeration significantly enhanced chemical oxygen demand, NH4+-N, and total nitrogen (TN) removal and the enrichment of nitrogen removal functional genes (amoA, nxrA, napA, narG, nirK and qnorB) compared to the non-aerated SWIS, especially for high HLRs. IA SWIS (79.7%–85.8%) had a better performance on TN removal compared with CA SWIS (73.8%–82.2%) when the HLRs ranged from 0.06 to 0.3 m3/(m2 d). Intermittent aeration is a sensible strategy to achieve high HLR, good nitrogen removal performance and comparatively low operation cost for SWISs.

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Nitrogen removal during secondary treatment by aquatic systems

Water Science & Technology ◽

10.2166/wst.2004.0879 ◽

2004 ◽

Vol 48 (11-12) ◽

pp. 355-361 ◽

Cited By ~ 2

Author(s):

B. Erol Nalbur ◽

L. Akça ◽

H. Bayhan

Keyword(s):

Nitrogen Removal ◽

Aquatic Plant ◽

Loading Rate ◽

Lemna Minor ◽

Domestic Wastewater ◽

Secondary Treatment ◽

Mass Loading ◽

Loading Rates ◽

Hydraulic Loading ◽

Nitrogen Conversion

Within the context of this study, two lab-scale aquatic plant reactors consisting of duckweed (Lemna minor) ponds, were investigated for the removal of nitrogen forms during the secondary treatment of domestic wastewater. TKN, NH3-N and NO3-N parameters have been measured in both reactors for hydraulic retention times ranging from 3.3 days to 23 days and at various distances from the inlet of reactors. The results were evaluated for hydraulic retention times, hydraulic loading rates and mass loading rates. It was concluded that hydraulic and mass loading parameters were more meaningful than hydraulic retention time. Optimum nitrogen removal values of hydraulic loading rate and mass loading rate were found to be 1.2 cm/day and 90-160 mg TKN/m2-day, respectively. At the higher and lower loading rates, nitrogen removal efficiency was lower than those at optimum conditions. Effluent TKN concentration was around 2.5 to 3.0 mg/l while NH3-N concentration was almost zero at these loading conditions. On the other hand, effluent NO3-N concentrations changed between 7 mg/l to 11 mg/l. When investigating the longitudinal profile, values were reduced rapidly along the reactors. It was concluded that most of the nitrogen conversion occurred at the beginning of the reactor.

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Improvement of organic matter and nutrient removal from domestic wastewater by using intermittent hydraulic rates on earthworm–microorganism biofilters

Water Science & Technology ◽

10.2166/wst.2020.139 ◽

2020 ◽

Author(s):

C. Chicaiza ◽

L. Huaraca ◽

C. E. Almeida-Naranjo ◽

V. H. Guerrero ◽

C. A. Villamar

Keyword(s):

Organic Matter ◽

Redox Potential ◽

Nutrient Removal ◽

Loading Rate ◽

Domestic Wastewater ◽

Nitrogen And Phosphorus ◽

Hydraulic Loading Rate ◽

Loading Rates ◽

Hydraulic Loading ◽

Global Performance

Abstract Biofilters based on earthworms–microorganisms represent, particularly in developing countries, an interesting alternative for domestic wastewater treatment due to their easy operation and low cost. However, there are several operational aspects that should be better understood in order to improve their performance. This paper studies the effect of using intermittent hydraulic loading rates to improve organic matter and nutrient removal from domestic wastewater using these biofilters. Three laboratory-scale columns, operating at a 2.5 m3 m−2day−1 hydraulic loading rate, were used. The B1–24 h, B2–8 h, B3–4 h column loading rates indicate that the columns were operated continuously for 24, 8 and 4 h, respectively. Each column (biomass biofilm/earthworms, redox potential, and head loss) and its corresponding operational performance parameters (TCOD, NH4+, NO3−, NO2−, TP) were monitored. The results showed that the B2–8 h intermittent hydraulic loading rate results in the best global performance, with 74%, 57%, and 20% average removal efficiencies for TCOD, nitrogen, and phosphorus, respectively. Moreover, it showed the best biomass growth (biofilm and earthworms), activity (as redox potential changes) and the lowest clogging effects (up to −1.0 cm). The intermittent operation influences the behavior of the earthworm–microorganism biofilters and offers the possibility of optimizing its global performance and achieving a resilient technology.

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Research on combined cage-in-pond culture systems for South-East Asia.

10.1079/ac.66888.20203483353 ◽

2020 ◽

Author(s):

James Diana

Keyword(s):

Nile Tilapia ◽

Loading Rate ◽

Nutrient Retention ◽

Fertilization Rate ◽

Waste Products ◽

Efficient System ◽

Loading Rates ◽

Pond Culture ◽

Clarias Macrocephalus ◽

Series Of Experiments

Abstract Submerging a cage within a pond and intensively feeding fish in the cage is one method of using the waste products from cage culture in semi-intensive pond culture. Using hybrid walking catfish, Clarias macrocephalus x C. gariepinus, in cages and Nile tilapia, Oreochromis niloticus, at large in ponds, treatments of one or two cages per pond produced better results than higher stocking densities. These treatments resulted in net fish yields as high as 56 tonnes ha-1 yr-1, and the most efficient system in terms of nutrient retention was using one cage per pond. The systems with one cage per pond delivered 3.7 kg of nitrogen (N) and 1.0 kg of phosphorus (P) ha-1 d-1, and retained 48% of the N added in fish, whereas two cages resulted in 34% N retention. For P, the results were 61 and 42% retained in fish, respectively. This aquaculture system resulted in some reduction in nutrient enrichment of ponds compared to feeding alone. A second series of experiments conducted using large Nile tilapia in cages, with small Nile tilapia in the pond, showed the best results when cages were stocked at 50 fish m-3 and the pond at 1.4 fish m-3. Survival was 98.8% for caged tilapia, which grew from 120 to 456 g in 90 days, with a net annual yield of 18 tonnes ha-1. Open-pond tilapia grew from 16 to 124 g with 92% survival and a net annual yield of 6.2 tonnes ha-1. The daily waste loading rate was approximately 1.7 kg of N and 0.37 kg of P ha-1, lower than the optimal fertilization rate proposed by CRSP experiments of 4 kg of N and 1 kg of P. Caged and pond fish accounted for about 50% of the N applied to the pond and about 60% of the P. The dynamics of oxygen, ammonium and plankton were evaluated against total loading rates for all culture combinations. Oxygen levels declined dramatically (about 75-100%) in all loading rates of ponds and never reached levels approaching zero decline in oxygen. N increased with increased loading density of fish and a level of zero change in ammonium would occur at a loading rate of about 0.8 kg m-3. Plankton dynamics showed similar results, and a fish loading rate with zero change in chlorophyll a should occur at a loading rate of about 0.3 kg m-3. These results indicate that it may be possible to reduce N and plankton contents in effluent water, but doing so would require loading rates that are not economically feasible.

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Study on the performance of an up-flow aerated biofilter (UAB) in municipal wastewater treatments

Water Science & Technology ◽

10.2166/wst.1994.0543 ◽

1994 ◽

Vol 30 (11) ◽

pp. 25-33 ◽

Cited By ~ 7

Author(s):

Yoshimasa Watanabe ◽

Satoshi Okabe ◽

Tomochika Arata ◽

Yuji Haruta

Keyword(s):

Organic Matter ◽

Suspended Solids ◽

Municipal Wastewater ◽

Unique Feature ◽

Aeration Rate ◽

Loading Rates ◽

Hydraulic Loading ◽

Running Cost ◽

And Performance ◽

Activated Sludge Systems

A comprehensive wastewater treatment system that accomplishes oxidation of organic matter, nitrification, and denitrification was developed, and its characteristics and performance were investigated. A municipal wastewater was treated by an up-flow aerated biofilter (UAB), in which biofilms were developed on stainless meshes installed horizontally. This UAB exhibited a great potential ability of oxidation of organic matter, SS stabilization, and nitrification due to a unique aeration mechanism giving high DO concentrations with relatively low aeration rates. Another unique feature of the UAB was that attached biofilms on stainless meshes physically filtered out and/or adsorbed suspended solids in the wastewater in addition to the biological oxidation of organic matter. A stable nitrification could be achieved at HRT=10 hours corresponding to a hydraulic loading of 86 L m−2 d−1 and at a ratio of aeration rate to wastewater flow rate (A/W) of 2, which is considerably low as compared to aeration rates of typical activated sludge systems. This UAB system also could handle relatively high hydraulic loading rates. The UAB used in this study still have enough space to install more stainless meshes so as to reduce hydraulic loading rates resulting in the reduction of HRT and aeration rate, which leads to improvement of the system performance as well as reduction of the running cost.

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PEMANFAATAN TANAH VULKANIK DALAM SISTEM MULTIPLE SOIL LAYERING (MSL) TERHADAP PEMURNIAN AIR IRIGASI TERPOLUSI

Jurnal BiBieT ◽

10.22216/jbbt.v2i1.3085 ◽

2017 ◽

Vol 2 (2) ◽

pp. 49

Author(s):

Welly Herman ◽

Darmawan Darmawan ◽

Gusnidar Gusnidar

Keyword(s):

Irrigation Water ◽

Loading Rate ◽

Quality Standard ◽

High Ability ◽

Volcanic Soil ◽

Soil Mixture ◽

Hydraulic Loading Rate ◽

Hydraulic Loading ◽

Soil Layering ◽

Mesh Sieve

The research aimed to make Volcanic soil of Multiple Soil Layering (MSL) with different Hydraulic Loading Rate (HLR) on the purification of polluted irrigation water and to determine the appropriate HLR against purification of polluted irrigation water. The research used an MSL system of the same Soil Mixture Block (SMB) size from a study done by (Chen et al., 2007) arranged in an Acrylic box measuring 50 cm x 10 cm x 60 cm (PxLxT). Making SMB is done by mixing volcanic soil, sawdust, iron, charcoal that has been mashed by 50 mesh sieve, with a combination of 7: 1: 1: 1. The MSL system is supplied with irrigation water taken from the Gunuang Nago irrigation and Pasar Baru area, Cupak Tangah village, Pauh IX sub-district, Padang continuously with different HLR of 250 L/m2/day, 500 L/m2/ day and 1000 L/m2/day. From the result of this research, it is found that MSL system can decrease pollutant content in polluted irrigation water until the concentration below the water quality standard based on PP. 82 of 2001 and MSL system with HLR 250 L/m2/day have high ability in purifying BOD and COD and HLR 1000 L/m2/day has a high ability in purifying NH4+, NO2- and NO3- on polluted irrigation water. Tujuan penelitian ini adalah untuk menentukan pengaruh tanah vulkanik dalam sistem Multiple Soil Layering (MSL) dengan Hydraulic Loading Rate (HLR) yang berbeda terhadap pemurnian air irigasi terpolusi. Penelitian menggunakan sistem MSL dengan ukuran Soil Mixture Block (SMB) yang sama dari penelitian yang telah dilakukan (Chen, Sato, Wakatsuki, & Masunaga, 2007)yang disusun di dalam kotak Acrylic berukuran 50 cm x 10 cm x 60 cm (PxLxT). Soil Mixture Block terdiri dari tanah vulkanik, serbuk gergaji, besi, arang yang telah dihaluskan oleh ayakan 50 mesh, dengan perbandingan kombinasi 7:1:1:1. Sistem MSL dialirkan air irigasi yang diambil dari irigasi Gunuang Nago dan Kawasan Pasar Baru, Kelurahan Cupak Tangah, Kecamatan Pauh IX, Padang secara terus menerus dengan HLR yang berbeda yaitu 250 L/m2/hari, 500 L/m2/hari dan 1000 L/m2/hari. Dari hasil penelitian diperoleh bahwa sistem MSL mampu menurunkan kandungan zat pencemar pada air irigasi terpolusi mencapai kosentrasi di bawah baku mutu air berdasarkan PP No. 82 tahun 2001 dengan HLR 250 L/m2/hari mempunyai kemampuan yang tinggi dalam memurnikan kadar pencemar BOD dan COD sedangkan HLR 1000 L/m2/hari mempunyai kemampuan yang tinggi dalam memurnikan kadar pencemar NH4+, NO2- dan NO3- pada air irigasi terpolusi.

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Aeration characteristics of a rectangular stepped cascade system

Water Science & Technology ◽

10.2166/wst.2010.828 ◽

2010 ◽

Vol 61 (2) ◽

pp. 415-420 ◽

Cited By ~ 12

Author(s):

Sanjib Moulick ◽

Naresh V. Tambada ◽

Basant K. Singh ◽

B. C. Mal

Keyword(s):

Surface Area ◽

Loading Rate ◽

Experimental Results ◽

Step Height ◽

Optimum Number ◽

Hydraulic Loading Rate ◽

Hydraulic Loading ◽

Aeration Efficiency ◽

Stepped Cascade ◽

Independent Parameters

Aeration experiments, maintaining nappe flow conditions, were carried out on a rectangular stepped cascade of total height 3.0 m to determine the total number of steps, slope of the entire cascade and hydraulic loading rate at which maximum overall aeration efficiency occurs, keeping the surface area of individual steps constant. Based on dimensional analysis, the overall aeration efficiency at standard conditions (E20) was expressed as a function of square of total number of steps (N2) and dimensionless discharge (dc/h), where dc and h represent critical depth in a rectangular prismatic channel and individual step height respectively. An empirical equation with E20 as the response and N2 and dc/h as the independent parameters was developed based on the experimental results subject to 36 ≤ N2 ≤ 196 and 0.009 ≤ dc/h ≤ 0.144. The experimental results showed that the overall aeration efficiency (E20) for a particular step height of stepped cascade increases with increase in dc/h up to a certain value and then decreases. This may be due to at higher dc/h, i.e., at higher hydraulic loading rate, the flow approaches the transition zone and thereby aeration efficiency decreases. E20 was also found to increase with number of steps at any hydraulic loading rate, because of the increased surface area of fall. The optimum number of steps, slope of the entire stepped cascade and hydraulic loading rate were found to be 14, 0.351 and 0.009 m2/s respectively producing the maximum value of overall aeration efficiency of 0.90.

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