High Total Suspended Solids Research Articles

Meteorological Satellite Observations Reveal Diurnal Exceedance of Water Quality Guideline Thresholds in the Coastal Great Barrier Reef

The Great Barrier Reef (GBR) is a marine protected area subject to natural and anthropogenic disturbances. Water quality is critical for the health and protecting resilience of GBR coral ecosystems against the synergistic and cumulative pressures of tropical cyclones, marine heat waves, and outbreaks of crown-of-thorns starfish. The concentration of Total Suspended Solids (TSS) is a key water quality parameter measured at multiple spatio-temporal scales from in situ probes to satellite observations. High TSS concentrations can adversely impact coral and seagrasses on the inshore GBR. We present diurnal TSS derived from Himawari-8 Geostationary satellite observations at 10 min frequency and demonstrate its applicability for improved monitoring of GBR water quality. Diurnal TSS obtained from Himawari-8 observations were compared to TSS computed from in situ bio-optical measurements at the Lucinda Jetty Coastal Observatory (LJCO). The coastal waters at LJCO experience diurnal variability of TSS (~7 mg L−1), where magnitude peaks followed the slack tides, and the largest diurnal changes were associated with freshwater discharge residuals from the wet season. Exceedance maps revealed that TSS is above guideline thresholds in the open coastal and mid-shelf waters for ~60% of the valid monthly observations, including during dry season months.

Gold mining impairs the biological water quality of a culturally important river and UNESCO World Heritage Site in Nigeria

The UNESCO World Heritage Sites have special conservation regulations because they are recognized as having significant cultural and/or natural value. One of Nigeria's two UNESCO-designated World Heritage Sites is the Osun River. It has immense biodiversity values, which are currently being threatened due to gold mining activities within its catchment area. Thus, this study seeks to ascertain the current biological water quality of this culturally and internationally important river using ecological and ecotoxicological approaches. Samples were collected from three environmental compartments (i.e., water, benthic sediment, and macroinvertebrates) in both dry and wet seasons from the section of the river that flows through the UNESCO site. Findings revealed that the river's physiochemical water quality has immensely degraded on account of extremely high total suspended solids, extremely low water transparency, and low dissolved oxygen. Three heavy metals exceeded their permissible limits in drinking water; i.e., Cd (364–367 times higher), Pb (75–104 times higher), and As (35–67 times higher). The contamination factor indicated that the benthic sediments were contaminated with Cd and Au, while the geo-accumulation (Igeo) index only indicates contamination on account of Cd, though Au ranks second in order of Igeo. The composition of the river's macroinvertebrate fauna suggests that it has been severely impacted because there was almost no stress-sensitive Ephemeroptera-Plecoptera-Trichoptera taxon present (one taxon and one individual only). Almost all of the chosen heavy metals had bioaccumulated in the three functional feeding guilds of macroinvertebrates. The current levels of heavy metals in the three environmental compartments of the river pose a great risk to both freshwater biodiversity and human health. Thus, a re-channeling of the upstream effluents from the river or any other natural water is advised. Also, a periodic environmental audit of the river should be conducted until it recovers from the pollution stress.

Biomass and Productivity of Thalassia testudinum in Estuaries of the Florida Panhandle

Thalassia testudinum often dominates seagrass meadows of the Florida panhandle but few measurements of productivity, biomass, density, turnover or leaf area index in this region have been made. We targeted 5 estuaries located at similar latitudes, 30⁰ ± 0.3⁰N: Big Lagoon, Santa Rosa Sound, St. Andrew Bay, St. Joseph Bay, and St. George Sound. This study was one component of a collaborative partnership of state and local researchers examining factors preventing recovery in panhandle estuarine areas that had historically contained seagrass in the 1940s and 1950s. Measurements were made twice in 2016, once in June and then again in summer or fall, except in Santa Rosa Sound where measurements were made 3 times. In the estuaries sampled for the second time in July or August, aboveground productivity was greater than in June. St. Joseph Bay had the highest aboveground productivity (4.3 g/m2/d) and 1—sided leaf area index (4.2) while St. George Sound had the lowest values (0.41 g/m2/d and 1.0). Principal component analysis suggested that St. Andrew Bay, Big Lagoon and Santa Rosa Sound were the most similar, with higher values for shoot densities and leaf turnover and lower salinities and watershed:water ratios. St. Joseph Bay had high aboveground productivity and salinity, and low turbidity. St. George Sound had low aboveground productivity, high total suspended solids and the highest watershed:water ratio. These baseline productivity estimates will be useful to assess the success of restoration efforts targeting seagrasses in the Florida panhandle and evaluate impacts of climate change on seagrasses.

Isolation and Characterization of Resistant Bacterial Species Isolated From Shallow Well Water Situated Close to Graves as a Public Health Menace in Osogbo, Osun State

This study was designed to evaluate the physicochemical and bacteriological qualities of well water situated close to graves. Total heterotrophic bacterial count (THBC), total coliform count (TCC) and fecal coliform count (FC) were done on nutrient agar, MacConkey and Eosine methylene blue agar, respectively, using spread plate method at incubation conditions of 37℃ for 24 hours for THBC and TCC whereas 44.5℃ for 24-48 hours for fecal coliforms. Membrane filtration was used for Vibrio spp. count on TCBS agar while conventional biochemical method was performed for bacterial identification. Isolated bacteria were subjected for antimicrobial resistant testing using 8 families of antibiotics. Bacteria with MAR index value of ≥75 were sent for genomic identification and sequencing. The average value of the ten water samples analyzed over the period of study had high total suspended solids (mg/l), phosphate (mg/l); magnesium ion (mg/l) contents and a very low dissolved oxygen mg/L content. The THB count was (5.0×107-1.35×108 CFU/ml), TCC count (3.55×105- 1.04×106 CFU/ml), FC count (2.10×105-6.90×105 CFU/ml) while Vibrio spp. count was 45-144 CFU/100 ml and the MPN estimated reading for coliform was also high. The percentage occurrence and MAR index value of the bacteria isolated from the well water, respectively were Vibrio spp. 23%; 75, Klebsiella spp. 20%; 100, Bacillus spp. 14%; 100, Staphylococcus spp. 14%; 62.5, E. coli 12%; 62.5, Pseudomonas spp. 12%; 75, Glycomyces spp. 3%; 100 and Proteus spp. 3%; 50. The closeness of the well to the grave makes the decomposing leachates with high organic, inorganic, biological and poisonous metals sink into the underground aquifers. Stamford Journal of Microbiology, Vol.12 (1) 2022: 47-53

Coagulation and Flocculation Optimization Process Applied to the Sidestream of an Urban Wastewater Treatment Plant

Ammonium (NH4+) recirculation from the streams generated in the dehydration stage of the sludge generated in the anaerobic digestion of urban wastewater treatment plants (WWTPs), known as centrate or sidestream, produces a reduction in the efficiency of WWTPs. Given this scenario and the formulation that a WWTP should be considered a by-product generating facility (biofactory), solutions for ammonia/ammonium recovery are being promoted. These include a nitrogen source that reduces the need for ammonia production through the Haber–Bosch process. Therefore, the recovery of nutrients from urban cycles is a potential and promising line of research. In the case of nitrogen, this has been aimed at recovering NH4+ to produce high-quality fertilizers through membrane or ion exchange processes. However, these techniques usually require a pretreatment, which could include an ultrafiltration stage, to eliminate suspended solids and organic matter. In this case, the coagulation/flocculation (C/F) process is an economical alternative for this purpose. In this work, the sidestream from Vilanova i la Geltrú WWTP (Barcelona, Spain) was characterized to optimize a C/F process before being treated by other processes for ammonium recovery. The optimization was performed considering a bibliographic and experimental analysis of several operating parameters: coagulant and flocculant agents, mixing velocity, and operation time, among others. Then, the removal efficiency of control parameters such as turbidity, chemical oxygen demand (COD), and total suspended solids (TSS) was calculated. This optimization resulted in the use of 25 mg/L of ferric chloride (FeCl3) combined with 25 mg/L of a flocculant composed of silicon (SiO2 3%), aluminum (Al2SO4 64.5%), and iron salts (Fe2O3 32.5%), into a 1 min rapid mixing process at 200 rpm and a slow mixing for 30 min at 30 rpm, followed by a final 30 min settling process. The numerical and statistical results of the process optimization reached 91.5%, 59.1%, and 95.2% removal efficiency for turbidity, COD, and TSS, respectively. These efficiencies theoretically support the enhanced coagulation/flocculation process as a pretreatment for a higher NH4+ recovery rate, achieving 570.6 mgNH4+/L, and a reduction in the dimensioning or substitution of other membrane processes process due to its high TSS removal value.

Quality Index of Borehole Water in Marmara and New Site Communities of Wukari, Nigeria

The fitness of groundwater has continued to deteriorate due to increasing population, commercialization, and urbanization, among others. Water quality can be assessed on physical, chemical and biological basis. This study evaluates the physicochemical properties and quality index of borehole water in Marmara and New site community of Wukari Local Government area using standard procedure. Result showed that the mean pH, Total Dissolved Solids (TDS), Total Suspended Solids (TSS), alkalinity, Biological Oxygen Demand (BOD) and nitrates were 6.6 and 6.9; 111.6 and 385 mg/L; 34.6 and 33.4 mg/L; 102.4 and 150 mg/L; 21.69 and 8.42 mg/L; 31.51 and 16.85 mg/L; 8.98 to 18.30 mg/L for Marmara and New site borehole water samples respectively and are within the permissible limit of the World Health Organization. Marmara recorded the highest pH, temperature, dissolved oxygen, TDS, alkalinity and nitrate while New site had higher total suspended solids, COD and BOD. WQI values of 86.03 and 80.22 were obtained in borehole water sourced from New site and Marmara respectively, rating the quality of borehole water in this study good and, on further purification, can serve for drinking and other domestic applications.

Characterisation of aluminium industrial wastewater and investigation of recovery alternatives

Aluminium industry is one of the largest sectors and wastewater generated from this industry could cause crucial environmental problems due to its high heavy metal concentration and conductivity. Therefore, this study aims to determine the characterisation of the wastewater discharged from the two aluminium facilities by considering water recovery potential. While Facility-A produces stainless steel kitchenware, such as pots and pans, In Facility-B, anodised coating takes place from secondary aluminium and wastewater is generated from the units where anodised coating baths and control processes are carried out. For the analyses, the wastewater composite samples from different sections, such as washing, sand-blasting and dyeing in Facility-A were taken in 2 and 24 hours. In Facility-B, three 2-hour composite influent water samples and an effluent sample from chemical wastewater treatment were taken to determine conductivity, pH, chemical oxygen demand (COD), total suspended solids (TSS), etc. As a result of the analyses made, a high value of TSS was detected at all sampling points in Facility-A. It was also seen that the conductivity after demineralisation process in Facility-A was below 30. In Facility-B, it was determined that while the pH obtained from two influent samples was below the discharge limits and showed acidic characteristics, one sample was very basic with a pH value of 12.19 and exceeds the upper limit of discharge. All influent samples in Facility-B show high TSS content in comparison with discharge limits specified in the regulation.

Pengaruh Waktu Kontak dan Bobot Biomassa Kangkung Air (Ipomoea aquatica) Terhadap Penurunan Kadar Total Suspended Solid (TSS) Air Limbah Rumah Sakit dengan Metode Fitoremediasi

Hospital waste water is one of the causes of environmental pollution. Where river pollution is one of the effects (Sari et al., 2020). The high content of Total Suspended Solid (TSS) is the one of the parameters of river pollution. High TSS content in rivers has the potential to cause siltation (Ruhmawati et al., 2017). So that the management of hospital waste water is very important (Sari et al., 2020). One of the economical waste treatment methods is the phytoremediation (Novita et al., 2019). The research was conducted by mixing wastewater with acclimatized water (1:1), then 4 liters were taken and put into a container containing water spinach with a weight of (50, 100, 150, 200, 250) grams. Tests were carried out with variations in contact time (1, 2, 3, 4, 5) days. Samples were taken as much as 500 ml and then tested for its TSS content. It was concluded that contact time had an effect on decreasing TSS levels, while for biomass weight it had no effect. In addition, it was found that the effectiveness of water spinach in reducing the highest TSS level was 85% with a TSS level of 3 mg/L which occurred on a weight variation of 250 grams on the second day and at a weight of 100 and 200 grams on the third day, which means that water spinach was quite effective in reducing TSS levels in hospital wastewater.

Integrated system for recycling and treatment of hazardous pharmaceutical wastewater

This study aimed to investigate an integrated system that can deal with different pharmaceutical wastewaters. Pharmaceutical wastewater was subjected to biological, chemical and advanced oxidation according to its pollutant’s nature. Wastewater with high total suspended solids (TSS 480 mg/L) was subjected to a conventional chemical treatment process utilizing different coagulants. The best results were obtained by using calcium oxide and alum added with calcium oxide where the removal efficiency of COD was 46.8% and 51%. Highly loaded pharmaceutical wastewater (COD 9700 mg/L, BOD/COD 0.16) had been subjected to Fenton oxidation, the removal of COD reached 80.4%, and the ratio of BOD/COD is enhanced to 0.6. Photocatalysis by using different nanomaterials was applied to pharmaceutical wastewater containing 10 mg/L of phenols. Phenol is completely removed by using mesoporous TiO2 after 90-min irradiation and after 120 min in the case of TiO2/P25 and TiO2/UV 100 nanocomposites, while it is removed by 40% in case of using mesoporous TiO2/Ta2O5. Effluent-treated water from previous routes was subjected to biological treatment and followed with disinfection by using UV as post-treatment. The final COD was 40, and it matches with the Egyptian practice code for water reuse in agriculture (ECP 501 in Egyptian code of practice for the use of treated municipal wastewater for agricultural purposes. The ministry of Housing Utilities and Urban Communities., n.d. No title, 2015). Results showed also using treated wastewater in irrigation of barley and bean seeds achieved germination ratio up to 71% in barely and 70% in bean compared with that irrigated with Nile water, which reached 70% and 75%, while it was about 16.6% and 30% in case of irrigation with untreated wastewater (Jeong et al. in Water (Switzerland). https://doi.org/10.3390/w8040169, 2016).

High suspended solids removal of Indian drain water with a down-scaled Dissolved Air Flotation (DAF) for water recovery. Assessing water-type dependence on process control variables

The Barapullah drain crosses through New Delhi, India, and transports millions of cubic meters of stormwater, municipal sewage and industrial sewage to the Yamuna River. Seasonal variations and ambiguous annual discharges cause 20-fold fluctuations in hydraulic flows, pollutants type and concentration. Furthermore, New Delhi is among the most densely populated areas on the planet, with limited surface area and high water stress. Dissolved Air Flotation (DAF) units are known to be highly compact, robust, and an efficient suspended solids separation technology that enables further water recovery in a treatment train. Thus, a down-scaled column DAF was designed and used to determine the total suspended solids removal efficiencies, under different influent conditions. Three influents that resemble the Barapullah drain seasonal variations in composition, and a fourth that imitates the feed of DAF when located after an anaerobic bioreactor were tested. A total of 60 batch DAF experiments were completed and used to assess seven independent control variables for DAF operation, which are influent Total Suspended Solids (TSS), pH, temperature, DAF particles residence time, white water pressure, coagulants and flocculants concentration, and coagulation and flocculation time. Results showed that the down-scaled DAF could be steered from low to high removal efficiencies, comparable to full-scale systems. Maximum TSS removal varied between 92 and 96%. The effect and statistical relevance of the different performance variables on the measured separation efficiencies depended on the influent type. All variables, except temperature and pH, had a significant performance effect with a p-value below 0.1, for at least one influent. Pressure had a positive effect on separation efficiency, due to its importance in bubble formation. Moreover, the down-scaled DAF system had low removal efficiency for particles with spherical shapes, and diameters below 10 µm. Based on the high TSS removal for all tested influents, and the effect of the studied control variables, a full-scale DAF could efficiently remove the suspended solids of the Barapullah drain. The unit robustness for different flows and pollutant concentrations, and small footprint, show DAF suitability as part of a treatment train for water recovery, in densely populated areas.

Kemelimpahan anggang-anggang Ptilomera dromas Breddin (Hemiptera: Gerridae) di Sungai Ciliwung dalam kaitannya dengan kualitas air

Anggang-anggang Ptilomera dromas Breddin (Gerridae: Hemiptera) adalah serangga akuatik yang ditemukan di berbagai perairan, seperti sungai, kolam, dan danau. Penelitian ini mengkaji kemelimpahan P. dromas di Sungai Ciliwung dalam kaitannya dengan kualitas air. Kemelimpahan P. dromas disurvei di lima stasiun pengamatan, yaitu stasiun Cilember, Cijulang, Gadog, Katulampa, dan Sempur. Parameter lingkungan yang diukur di setiap stasiun adalah suhu air, suhu udara, pH, arus air, biological oxygen demand (BOD), dissolved oxygen (DO), CO2 bebas, total N, kesadahan air, dan total suspended solid (TSS). Hubungan antara kemelimpahan P. dromas dan parameter lingkungan dianalisis dengan general linier model (GLM). Hasil penelitian menunjukkan bahwa kemelimpahan P. dromas tertinggi terdapat di stasiun Gadog, diikuti oleh Cilember, Katulampa, dan Cijulang. Anggang-anggang P. dromas tidak ditemukan di stasiun Sempur diduga karena adanya penghalang berupa bendung Katulampa dan nilai TSS dan BOD yang tinggi. Berdasarkan analisis GLM, pH dan kesadahan air berpengaruh positif terhadap kemelimpahan P. dromas. Keberadaan P. dromas di stasiun penelitian bagian hulu sungai diduga berkaitan dengan kualitas perairan yang masih baik dan tingkat polusi yang relatif rendah.

Assessment of surface water quality and monitoring in southern Vietnam using multicriteria statistical approaches

The study was conducted to analyze surface water quality fluctuations in the the southern region of Vietnam using monitoring data at 58 locations. Seventeen water quality indicators were analyzed including pH, temperature, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), total suspended solids (TSS), chemical oxygen demand (COD), biological oxygen demand (BOD), ammoniacal nitrogen (NH4+- N), nitrite nitrogen (NO2−-N), nitrate nitrogen, iron (Fe), lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), and chloride (Cl− ions). The study used water quality index (WQI), cluster analysis (CA), principal component analysis (PCA), and Entropy weighted methods to analyze surface water quality. The results showed that the surface water was contaminated with organics (low DO and high TSS, BOD, COD), nutrients (high NH4+-N) and Fe. While Pb at some locations exceeded the allowable limit of the national technical regulation, other indicators (Cd, Hg and As) were within this standard. Moreover, DO, TSS, BOD, COD, NH4+-N, Fe, EC, TDS, and Cl− were seasonally fluctuated. WQI classified water quality from bad to very good (WQI = 42–100) due to the impact of hydrological conditions, navigation, wastewater from industrial zones, and fishing ports. The results of CA suggested that it is possible to reduce the 11 sampling locations (from 33 to 22 locations) in clusters 1–6 and the frequency of monitoring from 8 to 5 times per year, which still ensures representativeness of water quality over time. This reduction allows lowering the monitoring costs by 56.5%. The PCA identified five major potential sources explaining 87.3% and 8 minor sources explaining only 12.7% of water quality variation. Temperature, pH, EC, DO, BOD, COD, NH4+-N, NO2−-N, Fe, Cl−, Pb are important indicators need to periodically be monitored. Furthermore, orthophosphate, total phosphate, total nitrogen, coliforms should be considered to add into the next monitoring program. Locations with medium and bad water quality are concentrated in Dong Nai, Ho Chi Minh City and Long An, which requires finding effective solutions to improve the water quality. The current results can assist in decision-making related to environmental quality monitoring in the southern region of Vietnam.

Influence Of Activated Carbon On Total Suspended Solids And Relative Plugging Index Of Injection Water From X-Oilfield

Produced water will be used as injection water for water flooding need, but, based on the results of water quality tests show poor injection water quality caused by a lot of solids particles with high total suspended solids (TSS) concentration and high relative plugging index (RPI) obtained in the injection water. When, the condition of injection water without treatment is injected into formation will cause serious plugging. In this study, two methods used to minimize the high TSS and RPI problems are treatment with chemical and filtration (activated carbon). The use of optimal concentration of scale inhibitor in the injection water can reduce TSS and RPI in the injection water, but it does not work effectively, so that its water quality is still poor water quality and can cause plugging in the formation. Another method is filtration with activated carbon filter media which has characteristics of adsorption and large specific area to filter insoluble materials in the injection water. After filtration, the filtrate of the injection water results in clear water condition. Based on the results of laboratory tests indicate that the filtrate of the injection water contains the least solids particles with small particle size, low total suspended solids concentration and low relative plugging index value. When, it is injected into formation, the possibility of plugging occurrence can be minimized, although, there is increase of pH value, but, in general, the filtrate of the injection water can be categorized good water quality

Influence of the Sludge Retention Time on Membrane Fouling in an Anaerobic Membrane Bioreactor (AnMBR) Treating Lipid-Rich Dairy Wastewater.

This study evaluated the effects of sludge retention time (SRT) on the membrane filtration performance of an anaerobic membrane bioreactor (AnMBR) fed lipid-rich synthetic dairy wastewater. The membrane filtration performance was evaluated in two AnMBR systems operated at two different SRTs, i.e., 20 and 40 days. For the AnMBR operated at 40 days, SRT exhibited worse membrane filtration performance characterized by operational transmembrane pressures (TMP) exceeding the maximum allowed value and high total resistances to filtration (Rtotal). The sludge in the two reactors evaluated at the different SRTs showed similar sludge filterability properties. However, the sludge in the reactor operated at 40 days SRT was characterized by exhibiting the highest concentrations of: (i) total suspended solids (TSS), (ii) small-sized particles, (iii) extracellular polymeric substances (EPS), (iv) soluble microbial products (SMP), (v) fats, oils and grease (FOG), and (vi) long-chain fatty acids (LCFA). The cake layer resistance was the major contributor to the overall resistance to filtration. The high TSS concentration observed in the AnMBR systems apparently contributed to a less permeable cake layer introducing a negative effect on the membrane filtration performance.

High discharge intensified low net ecosystem productivity, hypoxia, and acidification at three outlets of the Pearl River Estuary, China

Clarifying the influence of hydrological variations on ecological function is a topic of considerable interest in watershed ecological flow assessment and water resource management. Net ecosystem productivity (NEP) is a useful composite indicator of ecosystem function, reflecting material cycling and energy flow. However, the effects of hydrological variations on NEP, especially the influence mechanism, remain unclear due to the complex environmental characteristics in estuaries. We analysed the spatial–temporal variability of the aquatic environment and NEP through in-situ monitoring and field sampling from December 2018 to January 2020 at three outlets (Humen, Jiaomen, and Hongqimen) with different hydrological conditions in the Pearl River Estuary (PRE), China, and explored the influence mechanism of hydrological variation on NEP. The 155 groups of effective metabolism values were estimated using Odum's open-water method. The daily ecosystem respiration (ER) was higher than the gross primary production (GPP); therefore, water bodies were dominated by net heterotrophy at the three outlets. The daily NEP (–4.34 ± 1.40 mg O2 L–1d–1), O2 concentration (5.2 ± 1.02 mg L–1), and pH (7.53±0.24) were lowest at Humen, which also had the largest discharge and tide volume, deepest water depth, and widest channel. Seasonally, the NEP in the summer (–3.30 ± 1.39 mg O2 L–1d–1) and autumn (–3.19 ± 1.60 mg O2 L–1d–1) was lower than those in the spring (–1.56 ± 1.92 mg O2 L–1d–1) and winter (–2.17 ± 1.50 mg O2 L–1d–1). The inhibitory effect of increased discharge on the metabolic rate exceeded the stimulation provided by seasonal factors, such as increased temperature and solar radiation. The scour and dilution effect caused by discharge increase reduced chlorophyll a concentration; meanwhile, the increase in turbidity resulted in a decrease in the photosynthetic rate and GPP. ER was stimulated by heterotrophic microorganisms and high total suspended solids, resulting in a decrease in O2 and endogenous organics, thus causing the low NEP, hypoxia, and acidification phenomenon. Our results suggest that lengthening the discharge pulse period in summer and autumn will further decrease NEP and increase the area of hypoxia and acidification at the three outlets in the PRE.

Particle size distribution and total suspended solid concentrations in urban surface runoff

An in-depth understanding of particle size distribution as well as total suspended solids (TSS) in surface runoff is essential for managing urban diffuse pollution. In this study, field experiments and model simulation were undertaken to explore and confirm the dynamic runoff behaviour of TSS and their influencing factors. Field observation results showed that samples with high TSS concentrations contained coarser particles (>100 μm) during three natural rainfall events. Particle size distribution as well as road-deposited sediments (RDS) amount before and after these rainfall events also confirmed that a higher percentage of washed-off coarser particles resulted in higher TSS concentrations in surface runoff water. The impacts of rainfall characteristics, urban-rural gradients, surface roughness, and climate difference on particle distribution as well as TSS concentration were analyzed using the wash-off formula of particle size. These factors mainly affected the contribution rate of RDS to TSS by altering particle size composition; rates ranged from 4% to 44% under different rainfall characteristics. The critical particle size (<100 μm) was developed according to the mass percentage of particles with different sizes in RDS and TSS. Our results can provide a simple and effective way of assessing RDS contribution to TSS in surface runoff.

TEMPORAL AND SPATIAL VARIATIONS OF SELECTED WATER QUALITY PARAMETERS IN SERGESTID SHRIMPS’ HABITAT ALONG COASTAL WATER OF MIRI, SARAWAK, MALAYSIAN BORNEO

Evidences have shown that coastal water as habitat that support various flora and fauna as well as nursery ground which highlight the importance of water quality monitoring that act as basis for productivity of fisheries. Therefore, the objective of this study is to analyse the temporal and spatial variations of selected water quality parameters in sergestid shrimp’s habitat along the coastal water of Miri, Sarawak. Nine water quality parameters namely dissolved oxygen (DO), temperature, turbidity, pH, salinity, chlorophyll a (chl a), total suspended solid (TSS), nitrate (NO3-) and orthophosphate (PO43-) were measured in four stations along Miri coastal water. The variation explained by the principal component analysis had a total variance of 55.95%. The PC1 shows that the waters in July 2017, September 2017, October 2017, December 2017 and January 2018 were characterized with high turbidity and TSS as well as low temperature and salinity. In contrast, stations in November 2017, March 2018 and April 2018 had warmer and clear water with high salinity reading, whereby blooms of sergestid shrimps were observed in March and April 2018. The PC2 result shows that in May 2017 and June 2017, coastal waters were characterized with low pH reading. Overall, the water quality parameters measured in all stations were close to the standard value of Class E of Malaysian Marine Water Quality Standards (MMWQS).

Analisis Kualitas Air Pasca Tambang Emas d i Desa Wumbubangka , Kec a matan Rarowatu , Kabupaten Bombana

Southeast Sulawesi Province has great mining potential to support Indonesia's national mining. Especially in Bombana Regency, it has the potential for gold mining, but with mining activities, the mining area becomes nutrient-poor and toxic. Based on this research, we observed the levels of pH, mercury (Hg), Total Suspended Solid (TSS), Copper (Cu) that accumulated in the waters around the gold mining area. The results showed that the pH level in sector 1 was 9.5 and sector 2 was 9.72. The Hg level also shows -0.0021 mg/L and -0.0014 mg/L. On the other hand, the high TSS content for sector 1 was 930 mg/L due to the sampling point being very close to the gold mining sector, while sector 2 started to decline by 410 mg/L. Cu analysis showed the same value, namely -0.00032 mg/L, it was concluded that the gold quality in sectors 1 and 2 had the same grade.

Multivariate approach to evaluate the factors controlling the phytoplankton abundance and diversity along the coastal waters of Diu, northeastern Arabian Sea

The present study investigated the phytoplankton assemblage and diversity with physicochemical parameters of Diu coastal waters in different seasons during 2018–19. During the study period, 61 phytoplankton species comprising diatoms (50 sp.), dinoflagellates (8 sp.), and cyanophyceae (3 sp.) were recorded. Diatom was found to be a major community and contributed 79 to 99% of total phytoplankton abundance. Reduction in dinoflagellate and dominance of pennate-diatoms were observed during the monsoon. Chlorophyll-a concentration also showed a similar trend and decreased during the monsoon. However, the phytoplankton abundance was low particularly during the monsoon which might be due to the elevated total suspended solids (TSS) load. Canonical correspondence analysis revealed that diatoms were able to survive in high TSS with the support of high nutrients; while dinoflagellates were limited due to those conditions. Overall, the reduction in phytoplankton abundance, diversity, and biomass was recorded due to the elevated TSS input along the coastal waters of Diu.

Removal of micropollutants from municipal wastewater by membrane bioreactors: Conventional membrane versus dynamic membrane

In this study, fate of micropollutants was investigated in a membrane bioreactor (MBR) having dynamic membrane (DM) and ultrafiltration (UF) membrane for the treatment of raw municipal wastewater. Removal efficiencies of different micropollutants including sulfamethoxazole, ciprofloxacin, trimethoprim, caffeine and acetaminophen were assessed. A commercial hollow fiber UF membrane was used in parallel with a DM that was formed on a low-cost hollow fiber support material, made of polyester. MBR was operated at a flux of 10 L/m2·h. High total suspended solids (>99%) and chemical oxygen demand (>91%) removal efficiencies were achieved with each membrane. Besides, high removal efficiencies of micropollutants (>68.3->99.7%) were achieved. Morphological analyses were conducted for each membrane in order to get insight to the cake (dynamic) layer that was accumulated on the membrane. DM technology provides an effective alternative to the conventional membrane systems for micropollutant removal from municipal wastewater.