Suspended particulates decline along a dense mussel bed in a small Minnesota stream, U.S.A.

Water filtration by freshwater mussels is a valued ecosystem service; however, it has not been well studied in natural settings. To examine the potential influence of mussel filtration on suspended particulates, we measured the concentration of Escherichia coli, chlorophyll-a, and total suspended solids along a stream reach with a dense mussel assemblage (Mussel Site) and a stream reach with no mussels (Reference Site). We predicted that these particulates would show greater declines along the Mussel Site than the Reference Site because of mussel filtration. We collected three replicate water samples at upstream, midpoint, and downstream stations at both sites in August, September, and October 2022 to measure concentration values. In accordance with our predictions, concentrations of particulates declined from upstream to downstream at the Mussel Site but not at the Reference Site. We used linear mixed-effect modeling to determine that the interaction between mussel presence (Mussel Site, Reference Site) and sample location (upstream, midstream, downstream) best explained these patterns. There was lower support for the total suspended solids interactive model (AIC weight = 0.45) compared to the other two particulates (AIC weight > 0.95). Selective feeding by mussels may help to explain the lower support of the total suspended solids model. Our results suggest that mussels can appreciably reduce suspended particulate concentrations including harmful bacteria. This study provides a useful example of the ecosystem services mussels provide and why their conservation is needed.

Deer Creek Reservoir, located in Utah, supplies municipal and agricultural water for Utah and Salt Lake counties. During the past four decades the high levels of total phosphorus and dissolved oxygen in the water have introduced both taste and odor problems from algae growth, which have necessitated additional treatment to clean the water. In an attempt to discover why late summer algae blooms continue to persist at Deer Creek, the Brigham Young University Deer Creek Research Group collected data using several water quality laboratory tests on samples from 11 different sampling sites within the reservoir: total solids (TS), total suspended solids (TSS), total volatile suspended solids (TVSS), and phosphate. These tests were performed on samples collected during the summers of 2010 (May through October) and 2011 (April through November). Samples from Secchi depth were used for this analysis because of excessive variability introduced if samples from above and below the thermocline and at bottom layers of the reservoir were included. The purpose of this study is to determine if any correlations exists between these three measurements: solid, phosphate, and Secchi depths. We used total suspended solids as an indicator for algal mass. We suspect that phosphate is being trapped in solid material, specifically sediment, and being released into the reservoir slowly over time. Our analysis shows that solids at Deer Creek do not exhibit significant correlations with phosphate or Secchi depths. We suggest that a different approach to the phosphate problem be used that we should analyze and correlate Deer Creek phosphate with sediment oxygen demand (SOD) measurements taken using SOD chambers to correlate algae with potential phosphate release from sediments.

The environmental problems caused by the increase of pollutant. It is the result of industrial waste and environmental accidents. One of the main sources of water pollution is suspended solids. When these suspended particles settle to the bottom of a water body, they become sediments. Optical methods offer two possibilities: scattering and transmission. The design of optical sensor systems is based on the interaction between the photons of the electromagnetic radiation and suspended particles in water. Pollution usually results in higher total suspended solids (TSS) concentrations or turbidity. Water pollution is caused by any chemical, physical or biological change in the quality of water. Suspended solids are small particles of solid pollutants that float on the surface of, or are suspended in waters. Water pollution has become increasingly critical in this present-day, whether in the developed or the developing countries. Total suspended solids (TSS) in water can be detected by a number of optical sensing techniques, which involve light interaction with suspended particles in water. The measurements of the transmittance give a method for determining the concentration of the particles. The objectives of this study are to derive multispectral absorption algorithm and to develop an optical system, which is based on absorption measurements for measuring the concentration of total suspended solids, TSS in water. The multispectral absorption algorithm has been developed and a new multispectral optical sensor system designed for measuring total suspended solids TSS concentrations in polluted water. The development of the optical algorithm was based on the Beer-Lambert law. Firstly, the water samples used for calibration were filtered and dried to obtain the TSS values. In this study, three light emitting diodes were used as sensing emitters (sources) and a silicon phototransistor as radiations detector. The radiation values were determined from the output voltage readings of the sensor system. An electronic circuit was designed and the readings were measured by using a digital multimeter. The major advantages in using an LED as the light sources are its relatively low power consumption and ability to be modulated electronically at rapid rates. Standard polluted samples were prepared for sensors calibration. As the concentration of total suspended solids P was increased, the intensity of the transmitted light decreased. The level of the photocurrent was linearly proportional to the pollutants concentration. The proposed multispectral algorithm was calibrated using the measured parameters. Its accuracy was determined based on correlation coefficient, R and the value of the root-mean square errors, RMSE. The results showed a good correlation between the radiation values and the total suspended solids concentrations. This optical system provides various advantages over the current portable turbidity meter, which uses a single infrared source. The main advantage is its capability provide water pollution levels accurately (i.e. total suspended solids concentration). It only requires inexpensive components and can be assembled easily. The proposed algorithm produced a high correlation coefficient and low root mean square error value. This new methodology is very important for measuring and monitoring TSS in polluted water areas.

Freshwater mussels (Order Unionoida) are one of the most imperiled taxonomic groups in North America. Recent attention on population restoration and augmentation in tidal areas of the Delaware Estuary with historic populations has proven challenging. Benthic conditions in urbanized areas may not provide readily suitable habitat to support larger mussel populations. Lower benthic shear stress and increased sediment stability may promote mussel retention and recruitment; however, few studies have examined how such physical factors govern habitat suitability in tidal freshwater systems. Various metrics associated with mussel population robustness and benthic physical conditions were correlated to explore feature of the benthic environment that might govern habitat suitability in the tidal Delaware River. Comparisons among several study sites suggest that sediments with lower percentages of silt, clay, and organic matter along with higher gravel content correlated with higher mussel density and biomass. The high mussel density site, at the Betsy Ross Bridge, demonstrated an average gravel content of 41%, sand 54.4%, and fine particles 4.6%. Particle transport rates over a 3 week period in May-June 2018 were higher at Betsy Ross, which could explain the site's higher percent gravel and lower percent fine sediments. Alternatively, the low mussel density Frankford Arsenal site demonstrated low particle transport and a high percentage fines and lower percent gravel. The low-density Cooper River site, however, demonstrated high particle transport and a high fine particle content and low gravel content. An experiment was designed at the low-density Cooper site to manipulate habitat conditions in order to stabilize sediments, reduce benthic shear stress, and potentially enhance habitat conditions for mussels. In fall 2017, experimental structures comprised of salvaged logs and cobble were constructed along a shallow subtidal shoreline of the Delaware River where the preexisting mussel abundance was greatly reduced compared to a nearby reference site. The structures were oriented to stabilize sediments and reduce benthic shear stress while not interfering with seston delivery. Passive Integrated Transponder (PIT) tagged Utterbackiana implicata and Elliptio complanata were subsequently deployed into each structure and untreated controls. Changes in Plaster-of-Paris "Clod" sphere dissolution rates, sediment grain size, and organic content were monitored for a full year starting in Fall 2017. Dissolution rates of clods were significantly lower in experimental structures and mussel retention averaged 71.6% in structures compared to 67.4% in control plots after 1 year. This suggests that the structures may have served as refugia from high flow that typically mobilize the substrate. If confirmed with extended monitoring, these results should support design of living shoreline projects aimed at boosting populations of native unionids. Bivalve shellfish food conditions in the freshwater tidal Delaware River were monitored from April 2017 to April 2018. Previous studies in the tidal Delaware River characterized general seston and chemical conditions; however, the availability and quality of seston food for bivalve shellfish was less studied. The quantity of food was measured as total suspended solids (TSS) and particulate organic matter (POM) and quality was measured as the percentage organic content, protein content, and carbohydrate content. Seston quantity was found to vary by season, site, and tide, whereas the seston quality was found to vary seasonally and tidally. Compared to previous studies in Delaware Bay and other bivalve food studies, the availability in the freshwater tidal Delaware River did not appear to be limiting bivalve shellfish during this study. As demonstrated in this study, sites like Cooper do have the capacity to support the nutritional needs of more mussels. However, sediment stability and benthic shear stress should be addressed when attempting to augment this population. Future studies to further resolve the relationships and mechanisms between freshwater mussels and the physical habitat constraints in tidal areas will help inform restoration planning and design.

The effectiveness of various filtration agents in the primary treatment of dairy processing wastewater was investigated in laboratory-scale studies. The filtration agents used were: zeolite, crushed coral, charcoal, sand and crushed coral and sand and glass beads. The effectiveness of the filtration media was determined by testing parameters such as chemical oxygen demand (COD), total solids (TS) and total suspended solids (TSS) before and after filtration of wastewater. Percent reduction of the different parameters as a result of filtration was calculated. Sand combined with crushed coral or glass beads was found to be the most effective filtering medium with an average reduction of 99% in TSS, 93% in COD and 51% in TS. Charcoal filtration resulted in an average 85% reduction in TSS, 83% reduction in COD and 46% reduction in TS. Filtration using crushed coral resulted in an average 83% reduction in TSS, 78% reduction in COD and 39% reduction in TS. Zeolite was the least effective of the four media; it resulted in an average reduction of 78% in TSS, 76% in COD and 30% in TS. The differences among mean values of COD, TSS and TS after the different treatments were analyzed statistically using analysis of variance (ANOVA). When differences among means were found to be statistically significant (p<0.0001), each mean value was compared with every other mean value using Duncan’s multiple range test and least significant difference (LSD) test. Comparison of the mean values indicated the following: No significant difference between means of zeolite and crushed coral treatment. Mean values of COD, TSS, and TS of charcoal treatment were significantly different from the other treatments. Sand combined with crushed coral or glass beads was the most effective filtration agent and the means were significantly different from the means of the other treatments.

Effects of Duration and Intensity of Aeration on Solids Decomposition in Pig Slurry for Odour Control

Transport of hydrophobic organic pollutants in rivers is mainly coupled to transport of suspended particles. Turbidity measurements are often used to assess the amount of suspended solids in water. In this study, a monitoring campaign is presented where the total concentration of polycyclic aromatic hydrocarbons (PAHs), the amount of total suspended solids (TSS), and turbidity was measured in water samples from five neighboring catchments in southwest Germany. Linear correlations of turbidity and TSS were obtained which were in close agreement to the literature data. From linear regressions of turbidity versus total PAH concentrations in water, mean concentrations of PAH on suspended particles could be calculated and these varied by catchment. These values furthermore comprise a robust measure of the average sediment quality in a given catchment. Since in the catchments investigated in this study, PAH concentrations on suspended particles were stable over a large turbidity range (1–114 Nephelometric Turbidity Units), turbidity could be used as a proxy for total PAHs and likely other highly hydrophobic organic pollutants in river water if the associated correlations are established. Based on that, online monitoring of turbidity (e.g., by optical backscattering sensors) seems very promising to determine annual pollutant fluxes.

Effects of broiler carcass bleed time and scald temperature on poultry processing wastewater

Stream water protection during timber-harvesting activities is of primary interest to forest managers. In this study, we examine the potential impacts of riparian zone tree cutting on water temperature and total suspended solids. We monitored stream water temperature and total suspended solids before and after timber harvesting along a second-order tributary of the Coleman River in northeastern Georgia, where logging with rubber-tired skidders was conducted in the riparian area along alternating 60-m stream reaches on the east side of the stream. We monitored temperature above the management unit (reference), at a location within the cut area (within cut), and at a third site 150 m below the cut area (below cut). We measured total suspended solids during base flow and storm flow, taking weekly stream water grab samples above the site and above and below each riparian area, for a total of six sampling locations. We found that stream water temperature following harvest increased within the cut area relative to the reference but decreased at the below sample site back to reference conditions. Overall, total suspended solids responses were minimal or nonexistent during base and storm flows within the cut relative to the reference site, and temperature responses were minimal. Unusually warm and dry weather existed for most of the logging period, which may have minimized the potential for runoff, erosion, and sediment; however, low flows may have contributed to the small increases in water temperature. Hence, we observed only marginal effects of riparian zone cutting on water temperature and total suspended solids in this study.

The disposal of dairy plant processing wastewater in a three‐stage aerated lagoon system was evaluated over a one‐year period. Aerators were fixed on the lagoon surfaces and designed to mechanically supply oxygen to the system. Monitored pollution parameters included flow‐rate, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total solids (TS), and pH. Microbiological parameters studied were heterotrophic plate count (HPC) and adenosine triphosphate (ATP) as measured by relative light units (RLU). The average daily effluent flow‐rate from the lagoon system was 163.3 x 103 L/d with 7 mg/L BOD5, 122 mg/L COD, 31 mg/L TSS, 652 mg/L TS, and 7.69 pH of effluent. An average BOD removal of 97% was achieved from the first lagoon sampling point to final pffluent, with 89% removal of COD, 93% removal of TSS, and 49% removal of TS. Overall, BOD was strongly correlated with the COD, TSS, TS, and pH. Also, COD showed a significant correlation with TSS and TS. Anothe...

This study aimed to evaluate the performance of combined constructed wetland systems (vertical – horizontal flow) in removing organic matter, cultivated with Tifton 85 grass (Cynodon spp.) and cattail (Typha sp.), using pretreated swine wastewater (from anaerobic systems) at variable loading rates. The experimental system was composed of six constructed flooded systems. The flow was frequently monitored by direct measurement, and subsequently, the pH, influent, and effluent concentrations of the variables total solids (TS) and total suspended solids (TSS) and chemical oxygen demand (COD) were determined. The results showed that the average removal of total solids (TS) and total suspended solids (TSS) did not change significantly (p &gt; 0.05) with increasing applied load in vertical flooded systems. While statistically significant differences (p &lt; 0.05) were observed for ST in VFCW3 in Phase III (801–540 mg.L−1, 33%) and for TSS in VFCW2, which showed 48% removal in Phase III (122–62 mg.L−1, 48%), indicating that specific configurations can improve system efficiency. On the other hand, the average removal of total suspended solids (TSS) did not change significantly (p &gt; 0.05) with increasing applied load in horizontal flooded systems. However, the average removal of total suspended solids (TSS) increased significantly (p &lt; 0.05) with increasing applied load in horizontal flooded systems. Therefore, it can be concluded that the COD removal efficiencies, in general, increased with the increase in the applied organic load, reaching approximately 50% (307–271 mg.L−1 VFC3 and 307–145 mg.L−1 HFCW3) for the VFCW‐HFCW set.

Total suspended solids (TSS) levels were monitored by SRL Environmental Sciences personnel at two locations in the Pen Branch Creek system in conjunction with K Reactor cold flow (pump) testing required as part of the reactor restart effort. The TSS data were compared with flow and rainfall data collected simultaneously in an effort to obtain insight on the suspension and movement for particulate material in the Pen Branch system in response to natural and operational causes. Pump testing clearly caused higher TSS levels at the two sampling locations. The artificially elevated TSS levels were more pronounced at a sampling location near the reactor than at a sampling location farther downstream. Although the environmental data provided by this study were obtained and used exclusively for process control and research purposes, rather than for formal regulatory compliance (i.e. NPDES monitoring), the TSS levels determined by the comprehensive testing were compared with NPDES limits required at various SRS outfalls. TSS values in Pen Branch were seldom in excess of these limits. Because of the relatively few times that TSS values at the two sampling locations exceeded ``typical`` NPDES limits, and the fact that occasional relatively high TSS values could clearly be solely attributed to rainfall, it was concluded that no major adverse environmental impacts were caused to the Pen Branch system as a result of the K-Reactor pre-operational pump testing.

Elevated suspended solids are a widespread stressor of aquatic ecosystems, but their effects on growth and reproduction in freshwater mussels are largely unknown. We fertilized experimental ponds to create a gradient in total suspended solids (TSS) and examined the effects of TSS on growth, nutritional status, reproduction, and clearance rate in Ligumia subrostrata. The number of females that became gravid declined sharply with increasing TSS, and no gravid females were found in the highest TSS treatments. The proportion of gravid females was not related to the TSS organic∶inorganic ratio. Fertilization was an all-or-nothing phenomenon. In all females that did become gravid, 98 to 99% of eggs were fertilized regardless of TSS, and total fecundity was unrelated to TSS. Clearance rates declined sharply as TSS increased but showed a threshold relationship in which clearance was uniformly low at TSS > ∼8 mg/L. Reproductive failure probably was not caused by poor body condition or nutritional status because growth (length and mass) and energetic status (measured as caloric density) were not related to TSS. We propose 2 mechanisms that implicate interference of TSS with fertilization as the cause of reproductive failure. Reduced clearance rate could decrease the chance of females encountering suspended sperm during filter feeding, or an increase in pseudofeces production could bind sperm in mucus and lead to its egestion before fertilization. Interruption of fertilization coincident with high TSS is a potential mechanism to explain the lack of mussel recruitment in many locations. Monitoring and reduction of TSS, especially during the spawning season, may help create conditions necessary for maintenance and recovery of mussel populations. More research is needed to explore the generality of this pattern across a broad range of mussel species including those adapted to lotic environments or that use different brooding strategies.

A 30-day bench-scale aeration experiment was carried out with three different aerationlevels, i.e., +35 mV ORP, 1.0 mg O2 L-1, and 3.0 mg O2 L-1, to treat swine manure with solids levelsfrom 0.5% to 4.0% for solids decomposition and odour control. Solids changes during the aerationprocess were characterized by total solids (TS), total volatile solids (TVS), total suspended solids(TSS), and total volatile suspended solids (TVSS). Volatile fatty acids (VFAs) was used to evaluatethe odour generation potential in the aerated manure. The overall TS removal efficiencies from 6.0%to 44.9%, 18.6% to 50.3%, and 42.3% to 56.4% were observed for the three different aeration levels,respectively, with reductions from 6.6% to 48.9%, 26.0% to 61.1%, and 57.3% to 69.9% for manureTVS. The ratios of TVS/TS, TSS/TS and TVSS/TS in manure were found to increase with solidslevels in the 30-day aeration process under the three aeration intensities. Reductions of BOD5reached 78.5% to 92.0%, 79.4% to 96.0%, and 91.2% to 97.0%, while reduction of VFAs reached12.7% to 99.0%, 71.7% to 99.0%, and 87.8% to 99.3%. The biodegradation of solids, BOD5, andVFAs was effectively enhanced when aeration length and level were increased. Low solids levels in manure offered a more advantageous condition for aerobic decompositions of solids, BOD5, andVFAs. Linear correlation analysis proved that the odour generation potential in manure being treatedby aeration process could be distinctly characterized by the change of solids in different forms and/orby the BOD5 levels.

A Laboratory Scale Sequencing Batch Reactor with the Addition of Acetate to remove Nutrient and Organic Matter in Pig Slurry