Displaying publications 41 - 60 of 176 in total

Abstract:
Sort:
  1. Diversity, extinction risk and conservation of Malaysian fishes
    Chong VC, Lee PK, Lau CM
    J Fish Biol, 2010 Jun;76(9):2009-66.
    PMID: 20557654 DOI: 10.1111/j.1095-8649.2010.02685.x
    A total of 1951 species of freshwater and marine fishes belonging to 704 genera and 186 families are recorded in Malaysia. Almost half (48%) are currently threatened to some degree, while nearly one third (27%) mostly from the marine and coral habitats require urgent scientific studies to evaluate their status. Freshwater habitats encompass the highest percentage of threatened fish species (87%) followed by estuarine habitats (66%). Of the 32 species of highly threatened (HT) species, 16 are freshwater and 16 are largely marine-euryhaline species. Fish extinctions in Malaysia are confined to two freshwater species, but both freshwater and marine species are being increasingly threatened by largely habitat loss or modification (76%), overfishing (27%) and by-catch (23%). The most important threat to freshwater fishes is habitat modification and overfishing, while 35 species are threatened due to their endemism. Brackish-water, euryhaline and marine fishes are threatened mainly by overfishing, by-catch and habitat modification. Sedimentation (pollution) additionally threatens coral-reef fishes. The study provides recommendations to governments, fish managers, scientists and stakeholders to address the increasing and unabated extinction risks faced by the Malaysian fish fauna.
    Matched MeSH terms: Water Pollution
  2. Studies on water quality and pathogenic bacteria in coastal water Langkawi, Malaysia
    Jalal KC, Faizul HN, Naim MA, John BA, Kamaruzzaman BY
    J Environ Biol, 2012 Jul;33(4):831-5.
    PMID: 23360015
    A study on physico-chemical parameters and pathogenic bacterial community was carried out at the coastal waters of Pulau Tuba island, Langkawi. The physico-chemical parameters such as temperature (27.43-28.88 degrees C), dissolved oxygen (3.79-6.49 mg l(-1)), pH (7.72-8.20), salinity (33.10-33.96 ppt), total dissolved solids (32.27-32.77 g l(-1)) and specific conductivity (49.83-51.63 mS cm(-1)) were observed. Station 3 and station 4 showed highest amount of nitrates (26.93 and 14.61 microg at N l(-1)) than station 1 (2.04 microg at N l(-1)) and station 2 (4.18 microg at N l(-1)). The highest concentration (12.4 +/- microg l(-1)) of chlorophyll a was observed in station 4 in October 2005. High phosphorus content (561 microg P l(-1)) was found in the station 2. Thirteen bacterial isolates were successfully identified using API 20E system. The highest amount of bacteria was observed at Station 4 (3400 CFU ml(-1)) and the lowest numberwas at Station 2 (890 CFU ml(-1)). Out of identified 13 Gram-negative bacterial isolates dominant species were Aeromonas hydrophila, Klebsiella oxytoca, Pseudomonas baumannii, Vibrio vulnificus, Proteus mirabilis, Providencia alcalifaciens and Serratia liquefaciens. Apart from this, oil biodegrading Pseudomonas putida were also identified. The study reveals the existing status of water quality is still conducive and the reasonably diverse with Gram-negative bacteria along the Pulau Tuba Langkawi.
    Matched MeSH terms: Water Pollution
  3. Fulltext An epidemiological investigation of an outbreak of leptospirosis associated with swimming, Beaufort, Sabah
    Koay TK, Nirmal S, Noitie L, Tan E
    Med J Malaysia, 2004 Oct;59(4):455-9.
    PMID: 15779577
    From October 13 to October 21, 1999, a total of 46 males, aged 8 to 19 years, were admitted to Beaufort Hospital after swimming in the creek near an oil palm plantation in Kampung (Kg) Kebatu, Beaufort. Thirty (30) presented with symptoms including fever, vomiting, bodyache, giddiness, headache, chest pain and cough, while 16 others, were asymptomatic. One, a 15 year old boy, died from haemorrhagic shock secondary to pulmonary haemorrhage. The onset of the illness was from 11 October to 19 October 1999. A case-control study found that the outbreak was associated with swimming in the creek (p<0.0001). A total of 44 paired sera samples were sent for microscopic agglutination test (MAT), 5 pairs showed sero-conversion, 3 pairs had 4 fold rise in titre and 18 pairs were positive at >320. The findings indicated that Leptospirosis was the cause of the outbreak of this illness and the contaminated creek water was the source of the infection. The occurrence of flooding and stagnation in the creek following the heavy rainfall during the first week of October 1999 could have contributed to the timing of the outbreak.
    Matched MeSH terms: Water Pollution
  4. Fulltext Field accumulation risks of heavy metals in soil and vegetable crop irrigated with sewage water in western region of Saudi Arabia
    Balkhair KS, Ashraf MA
    Saudi J Biol Sci, 2016 Jan;23(1):S32-44.
    PMID: 26858563 DOI: 10.1016/j.sjbs.2015.09.023
    Wastewater irrigated fields can cause potential contamination with heavy metals to soil and groundwater, thus pose a threat to human beings . The current study was designed to investigate the potential human health risks associated with the consumption of okra vegetable crop contaminated with toxic heavy metals. The crop was grown on a soil irrigated with treated wastewater in the western region of Saudi Arabia during 2010 and 2011. The monitored heavy metals included Cd, Cr, Cu, Pb and Zn for their bioaccumulation factors to provide baseline data regarding environmental safety and the suitability of sewage irrigation in the future. The pollution load index (PLI), enrichment factor (EF) and contamination factor (CF) of these metals were calculated. The pollution load index of the studied soils indicated their level of metal contamination. The concentrations of Ni, Pb, Cd and Cr in the edible portions were above the safe limit in 90%, 28%, 83% and 63% of the samples, respectively. The heavy metals in the edible portions were as follows: Cr > Zn > Ni > Cd > Mn > Pb > Cu > Fe. The Health Risk Index (HRI) was >1 indicating a potential health risk. The EF values designated an enhanced bio-contamination compared to other reports from Saudi Arabia and other countries around the world. The results indicated a potential pathway of human exposure to slow poisoning by heavy metals due to the indirect utilization of vegetables grown on heavy metal-contaminated soil that was irrigated by contaminated water sources. The okra tested was not safe for human use, especially for direct consumption by human beings. The irrigation source was identified as the source of the soil pollution in this study.
    Matched MeSH terms: Water Pollution
  5. Inactivation of insecticides by bacteria isolated from polluted waters where the mosquito larva bred in large number
    Hirakoso S, Kitago I, Harinasuta C
    Med J Malaya, 1968 Mar;22(3):249.
    PMID: 4386490
    Matched MeSH terms: Water Pollution
  6. Fulltext Achieving sustainable soil and water protection: The perspective of agricultural water price regulation on environmental protection
    Chou L, Dai J, Qian X, Karimipour A, Zheng X
    Agric Water Manag, 2021 Feb 28;245:106583.
    PMID: 33100487 DOI: 10.1016/j.agwat.2020.106583
    With the development of Chinese economy, more and more attention has been paid to environmental protection, the implementation of water price policy affects economic and environmental changes in China. This paper analyzes the impact of water price policy on agricultural land use and the scale of water pollution discharge in 240 cities in China between 2001 and 2017, by including data from China Urban Statistical Yearbook and China Land & Resources Almanac. The theoretical analysis of this study indicates that the optimal scale of pollution depends on the local initial endowment, economic investment capital and the marginal cost of environmental pollution caused by government's economic activities. Furtherly, the economic activities have a worsening impact on environmental pollution, but when the government implements environmental protection and water price policy measures in response to environmental pollution caused by economic activities, it has a significant impact on the decline in the scale of pollution. The government has promoted the pollution suppression model in the formulation of water prices, which has internalized the external cost of pollution in economic activities and can effectively reduce the scale of agricultural water pollution discharge.
    Matched MeSH terms: Water Pollution
  7. Clay-polymer nanocomposites: Progress and challenges for use in sustainable water treatment
    Mukhopadhyay R, Bhaduri D, Sarkar B, Rusmin R, Hou D, Khanam R, et al.
    J Hazard Mater, 2020 02 05;383:121125.
    PMID: 31541959 DOI: 10.1016/j.jhazmat.2019.121125
    Contaminant removal from water involves various technologies among which adsorption is considered to be simple, effective, economical, and sustainable. In recent years, nanocomposites prepared by combining clay minerals and polymers have emerged as a novel technology for cleaning contaminated water. Here, we provide an overview of various types of clay-polymer nanocomposites focusing on their synthesis processes, characteristics, and possible applications in water treatment. By evaluating various mechanisms and factors involved in the decontamination processes, we demonstrate that the nanocomposites can overcome the limitations of individual polymer and clay components such as poor specificity, pH dependence, particle size sensitivity, and low water wettability. We also discuss different regeneration and wastewater treatment options (e.g., membrane, coagulant, and barrier/columns) using clay-polymer nanocomposites. Finally, we provide an economic analysis of the use of these adsorbents and suggest future research directions.
    Matched MeSH terms: Water Pollution
  8. Fulltext Data for the industrial and municipal environmental wastes hazard contaminants assessment with integration of RES2D techniques and Oasis Montaj software
    Arifin MH, Kayode JS, Ismail KI, Abdullah M, Embrandiri A, Nazer SM, et al.
    Data Brief, 2020 Dec;33:106595.
    PMID: 33318980 DOI: 10.1016/j.dib.2020.106595
    Industrial, and municipal wastes are part of the main sources of environmental hazards as well as groundwater and surface water pollutions. If not well composed, treated, and safely disposed, it could permeate through the subsurface lithologies by reaching down to the underground water aquifers, particularly in zones of unprotected aquifer units. Pollutants, most especially the landfills leachates that encompassed organic contaminants, ammonia, nitrates, total nitrogen, suspended solids, heavy metals and soluble inorganic salts, i.e., soluble nitrogen, sulphur compound, sulphate and chlorides, could posed undesirable environmental impacts due to inappropriate disposals that may give rise to gaseous fumes and leachate formations. An electrical resistivity geophysical technique utilizing the RES2D no-invasive, cost-effective and rapid method of data collection was integrated with the 3D Oasis Montaj software to approximate the volume of the generated rectangular prism model of the contaminants delineated from mixtures of the industrial, and municipal wastes plumes to be 312,000 m 3.
    Matched MeSH terms: Water Pollution
  9. Water Quality Modelling for River Activities Management: Example from a Low- and Middle-Income Country
    Zahidi I, Wilson G, Brown K, Hou FKK
    J Health Pollut, 2020 Dec;10(28):201207.
    PMID: 33324504 DOI: 10.5696/2156-9614-10.28.201207
    Background: Rivers are susceptible to pollution and water pollution is a growing problem in low- and middle-income countries (LMIC) with rapid development and minimal environmental protections. There are universal pollutant threshold values, but they are not directly linked to river activities such as sand mining and aquaculture. Water quality modelling can support assessments of river pollution and provide information on this important environmental issue.

    Objectives: The objective of the present study was to demonstrate water quality modelling methodology in reviewing existing policies for Malaysian river catchments based on an example case study.

    Methods: The MIKE 11 software developed by the Danish Hydraulic Institute was used to model the main pollutant point sources within the study area - sand mining and aquaculture. Water quality data were obtained for six river stations from 2000 to 2015. All sand mining and aquaculture locations and approximate production capacities were quantified by ground survey. Modelling of the sand washing effluents was undertaken with the advection-dispersion module due to the nature of the fine sediment. Modelling of the fates of aquaculture deposits required both advection-dispersion and Danish Hydraulic Institute ECO Lab modules to simulate the detailed interactions between water quality determinants.

    Results: According to the Malaysian standard, biochemical oxygen command (BOD) and ammonium (NH4) parameters fell under Class IV at most of the river reaches, while the dissolved oxygen (DO) parameter varied between Classes II to IV. Total suspended solids (TSS) fell within Classes IV to V along the mid river reaches of the catchment.

    Discussion: Comparison between corresponding constituents and locations showed that the water quality model reproduced the long-term duration exceedance for the main body of the curves. However, the water quality model underestimated the infrequent high concentration observations. A standard effluent disposal was proposed for the development of legislation and regulations by authorities in the district that could be replicated for other similar catchments.

    Conclusions: Modelling pollutants enables observation of trends over the years and the percentage of time a certain class is exceeded for each individual pollutant. The catchment did not meet Class II requirements and may not be able to reach Class I without extensive improvements in the quality and reducing the quantity of both point and non-point effluent sources within the catchment.

    Competing Interests: The authors declare no competing financial interests.

    Matched MeSH terms: Water Pollution
  10. Single-step pyrolysis of phosphoric acid-activated chitin for efficient adsorption of cephalexin antibiotic
    Khanday WA, Ahmed MJ, Okoye PU, Hummadi EH, Hameed BH
    Bioresour Technol, 2019 May;280:255-259.
    PMID: 30772638 DOI: 10.1016/j.biortech.2019.02.003
    Cephalexin (CFX) antibiotic, a potent pharmaceutical water pollutant, was efficiently removed by activated carbon (AC) derived from a single-step pyrolysis of phosphoric acid-activated chitin. Experimental conditions such as temperature, CFX initial concentration, and solution pH were screened in batch adsorption. Phosphoric acid activation of chitin and subsequent pyrolysis tailored the Brunauer-Emmett-Teller surface area, total pore volume, and average pore diameter to 1199.02 m2/g, 0.641 cm3/g, and 21.37 Å, respectively. The Langmuir isotherm adequately described the equilibrium data for CFX adsorption on chitin-AC, with an R2 of 0.99 and a monolayer capacity of 245.19 mg/g at 50 °C. Chitin-AC showed higher adsorption capacity compared with other ACs derived from industrial and agricultural precursors. When activated by phosphoric acid, chitin-AC featured functional multi-sites for vast antibiotic adsorption treatment. Overall, chitin-AC could be a promising adsorbent for removal of CFX.
    Matched MeSH terms: Water Pollution
  11. Fulltext Application of Efficient Magnetic Particles and Activated Carbon for Dye Removal from Wastewater
    Moosavi S, Lai CW, Gan S, Zamiri G, Akbarzadeh Pivehzhani O, Johan MR
    ACS Omega, 2020 Aug 25;5(33):20684-20697.
    PMID: 32875202 DOI: 10.1021/acsomega.0c01905
    Since the turn of the 21st century, water pollution has been a major issue, and most of the pollution is generated by dyes. Adsorption is one of the most commonly used dye-removal methods from aqueous solution. Magnetic-particle integration in the water-treatment industry is gaining considerable attention because of its outstanding physical and chemical properties. Magnetic-particle adsorption technology shows promising and effective outcomes for wastewater treatment owing to the presence of magnetic material in the adsorbents that can facilitate separation through the application of an external magnetic field. Meanwhile, the introduction of activated carbon (AC) derived from various materials into a magnetic material can lead to efficient organic-dye removal. Therefore, this combination can provide an economical, efficient, and environmentally friendly water-purification process. Although activated carbon from low-cost and abundant materials has considerable potential in the water-treatment industry, the widespread applications of adsorption technology are limited by adsorbent recovery and separation after treatment. This work specifically and comprehensively describes the use of a combination of a magnetic material and an activated carbon material for dye adsorption in wastewater treatment. The literature survey in this mini-review provides evidence of the potential use of these magnetic adsorbents, as well as their magnetic separation and recovery. Future directions and challenges of magnetic activated carbon in wastewater treatment are also discussed in this paper.
    Matched MeSH terms: Water Pollution
  12. Fulltext Performance of Salvinia molesta plants in tertiary treatment of domestic wastewater
    Mustafa HM, Hayder G
    Heliyon, 2021 Jan;7(1):e06040.
    PMID: 33537482 DOI: 10.1016/j.heliyon.2021.e06040
    The objective of this study was to investigate the performance of different weight of Salvinia molesta plants in biological treatment of domestic wastewater. Three treatment systems containing 280g (GS1), 140g (GS2) and 70g (GS3) of S. molesta plants were used for the phytoremediation process. Physicochemical analysis such as pH, colour, chemical oxygen demand (COD), and biological oxygen demand (BOD5) of the influent and effluent water samples were performed according to spectrophotometric methods. The outcome of the study demonstrated that the different weight of S. molesta plants played a significant role in improving the quality of the wastewater samples, in which GS1 removed 96.8% (colour), 91% (BOD5), and 82.6% (COD). While up to 88.6% (colour), 87.1% (BOD5), and 81.1% (COD) reduction was observed for GS2 treatment systems, and GS3 was efficient in removing 85.5% (colour), 86.1% (BOD5), and 68.3% (COD). Also, a pH value of 6.29-7.19, 5.97-7.07, and 6.17-7.42 was obtained from GS1, GS2 and GS3 treatment systems, respectively. Thus, the treatment system with the highest quantity of S. molesta (GS1) demonstrated better performance compared to the other two systems (GS2 and GS3). The findings of this research can be applied in addressing the goals of sustainable development through the use of green technology to reduce the threat of water pollution in natural water bodies. Perhaps existing and future water scarcity can be resolved through the use of phytoremediation technology.
    Matched MeSH terms: Water Pollution
  13. Fulltext Investigating the use of date seed for removal of boron from seawater
    Ahmed, Moussa Mohamed, Nik Rashida Nik Abdul Ghani, Jami, Mohammed Saedi, Mirghani, Mohamed Elwathig Saeed, Md. Noor Salleh
    Biological and Natural Resources Engineering Journal, 2020;3(2):55-73.
    MyJurnal
    Boron has been classified as a drinking water pollutant in many countries. It is harmful to many plants, exceptionally sensible plants, and human health. Therefore, boron level needs to be decreased to 0.3 mg/L for drinking water and within 0.5 mg/L to 1 mg/L for irrigation water. In this study, various operational parameters namely pH, contact time and liquid/solid ratio were investigated to determine the potential of using date seed (or date pit or date stone) to remove boron from seawater. This study's main objective was to determine boron adsorption capacities of date seeds prepared by various methods (i.e., powdered, activated, acid-treated and defatted seed) by batch adsorption process using boron contaminated synthetic seawater. The process parameters of the selected biosorbent among the four date seed preparations methods were optimized. The surface characteristics were analyzed by using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). The results showed that acid-treated date seed was the best biosorbent in terms of removing 89.18% boron from aqueous solution at neutral pH, liquid to solid ratio of 5 within 2 hours of reaction time at room temperature (25°C±2°C).
    Matched MeSH terms: Water Pollution
  14. Fulltext SOLAR PHOTOCATALYTIC EFFICIENCY OF ZINC OXIDE FOR WATER DECONTAMINATION
    FARAH EILYANA MOHAMED
    UMT Journal of Undergraduate Research, 2019;1(1):92-102.
    MyJurnal
    Solar photocatalysis is a green technology that takes advantage of sustainable solar energy for enhancing oxidation process of numerous harmful water contaminants. In this study, a custom solar driven zinc oxide (ZnO)-mediated photocatalytic system was developed and its efficiency to remove organic contaminants as well as to disinfect selected bacteria was investigated. Methylene blue (MB) dye was used as the model organic contaminant, while Escherichia coli(E.coli) was used as the model fecal coliform bacteria in contaminated water. A series of photodegradation experiments were conducted on water contaminated with either 10 mg/L of MB or ~1010CFU/ml of E.coli. The experiments were completed under sunlight irradiation in the presence of 1 g/L of nano ZnO photocatalyst for up to 6 hours. Using a solar thermal collector, the photoreactor operated in the temperature range of 25 to 50 oC. The findings revealed that the combination of solar thermal with solar photocatalysis usingZnO intensified the degradation of MB and disinfection of E.coli. 98.08% of MB dye and 99.99% of E.coliwere successfully removed from the water within the first 3 hours of treatment. Almost complete removal was eventually achieved after 6 hours of treatment. It is therefore suggested that ZnO-based solar photocatalytic system developed in this study is highly efficient at enhancing water decontamination process.
    Matched MeSH terms: Water Pollution
  15. The Preparation and Characterization of Expanded Graphite via Microwave Irradiation and Conventional Heating for the Purification of Oil Contaminated Water
    Pham TV, Nguyen TT, Nguyen DT, Thuan TV, Bui PQT, Viet VND, et al.
    J Nanosci Nanotechnol, 2019 02 01;19(2):1122-1125.
    PMID: 30360214 DOI: 10.1166/jnn.2019.15926
    Recently, the graphite based materials have gained interest as excellent platforms to remove aqueous pollutants via adsorption routes. This is given that such materials possess large specific surface area and low density. In the present work, a comparative study of two facile and effective approaches is conventional thermal heating and microwave irradiation methods to fabricate expanded graphite from available flake graphite sources of Vietnam for oil-contaminated water purification. The as-prepared expanded graphite was characterized by using FT-IR, SEM, XRD and BET analysis. The results exhibited that expanded graphite has multilevel pore structures and the surface area of expanded graphite obtained from microwave irradiation and conventional heating was 147.5 (m²/g) and 100.97 (m²/g) under optimal processing conditions. The as-synthesized expanded graphite from the microwave irradiation method was found to have higher adsorption capacities for diesel oil, crude oil, and fuel oil compared to conventional heating method.
    Matched MeSH terms: Water Pollution
  16. Fulltext Acute gastroenteritis in Kinta
    Lili, Z.M., Noridah, O.
    Journal of Health Management, 2008;4(1):61-72.
    MyJurnal
    Acute Gastroenteritis (AGE) is common world wide and is a major health problem. The commonest cause is from contaminated water or food. Common infective agents are Rotavirus, Staph. aureus and Bacillus cereus. There was an AGE outbreak in Ipoh City from late August till early October 2006. Epidemiological and laboratory investigations were done. Fresh stool samples were taken from symptomatic patients. Water and food sampling were also done. Descriptive analysis of the outbreak was done. A total of 170 patients, mostly between 1 - 5 years of age, were affected. The highest incidents were seen in Bercham. Fever and diarrhea were the prominent features. Two stool samples (13.3%) were positive for E.coli and rotavirus respectively. Twelve of the twenty (60%) water samples taken were contaminated with coliform and fecal matter. Twenty-one of the eighty ((26.3%) food samples taken grew either E.coli, Staph. aureus or Bacillus cereus. It was concluded that a general source was responsible for this problem. The water supply to Ipoh City and the surrounding area is the most likely source. Novovirus was suspected as the organism involved because of the self-limiting and mild nature of the illness that occurred in this outbreak.
    The AGE outbreak in Kinta District in September 2006 is due to contaminated
    water supply from two water treatment
    Matched MeSH terms: Water Pollution
  17. Fulltext Novel method for gelatin extraction of various local fish using High Pressure Processing (HPP)
    Jamal, P., Jaswir, I., Yusof, N., Jami, M.S.
    International Food Research Journal, 2017;24(101):533-539.
    MyJurnal
    Gelatin from fish skin is known to be an alternative source for mammalian gelatin. However, it has weaker properties compared to bovine and porcine gelatin, which limits its use in the industry. The conventional method for fish gelatin extraction requires long production time and could cause serious water pollution and chemical treatments are often being used to enhance the yield of fish gelatin and its properties but it may affect the amino acid content of the gelatin. In this regard, High-Pressure Processing (HPP) is a novel method suggested for fish gelatin extraction. The HPP method is classified as green technology as it requires low electricity throughout the process. This study will discuss the impact of HPP the technique gelatin extracted from fish skin. Skins from four types of fish, namely red tilapia (Oreochromis niloticus), black tilapia (Oreochromis mossambicus), grouper (Epinephelus areolatus) and threadfin bream (Nemipterus tambuloides), were used. High pressure was applied at either pretreatment in citric acid solution or during thermal extraction; and the pressure was maintained at 250 MPa with pressure holding time of 10 minutes and 18 hours of water extraction. Gelatin extract from traditional acid-base method was prepared as a standard for comparison. The study found that there was an increment in the yield of gelatin and the concentration of gelatin extract, and the pre-treatment time was also reduced.
    Matched MeSH terms: Water Pollution
  18. Fulltext Magnetite nanoparticles in wastewater treatment
    Azdiya Suhada Abdul Rahim Arifin, Ismayadi Ismail, Abdul Halim Abdullah, Farah Nabilah Shafiee, Idza Riati Ibrahim
    The Pertanika Journal of Scholarly Research Reviews, 2016;2(3):108-122.
    MyJurnal
    Clean water is very important for health and well-being of humans and ecosystem. However, over the year, a billion tons of industrial waste, fertilizers and chemical waste were dumped untreated into water bodies, such as rivers, lake and oceans contributing towards water pollution, then threatening human health and ecosystem. Hence, the need for clean water has urged scientists to research and find solutions for improving water quality. Application of nanoparticles in wastewater treatment improves the environmental quality by elimination of harmful pollutants in wastewater. Magnetite is one of the nanoparticles used in wastewater treatment because of its specific large surface area, high reactivity in adsorption and recoverable from treated water via magnetic separation technology. Preparation method of magnetite nanoparticles is the important key to its adsorption efficiency.
    Matched MeSH terms: Water Pollution
  19. Water or sediment? Partitioning the role of water column and sediment chemistry as drivers of macroinvertebrate communities in an austral South African stream
    Dalu T, Wasserman RJ, Tonkin JD, Mwedzi T, Magoro ML, Weyl OLF
    Sci Total Environ, 2017 Dec 31;607-608:317-325.
    PMID: 28692901 DOI: 10.1016/j.scitotenv.2017.06.267
    Water pollution is a critical management issue, with many rivers and streams draining urban areas being polluted by the disposal of untreated solid waste and wastewater discharge, storm water and agricultural runoff. This has implications for biodiversity, and many rivers in the developing world are now considered compromised. We investigated benthic macroinvertebrate community structure and composition in relation to physico-chemical conditions of the water column and sediments. The study was conducted in an Austral catchment subject to both urban and agricultural pollutants in two different seasons. We assessed whether sediment characteristics were more important drivers of macroinvertebrate community composition than water column characteristics. We expected clear differences in macroinvertebrate community composition and in the associated community metrics due to distinct flow conditions between the two seasons. A combination of multivariate analyses (canonical correspondence analysis (CCA)) and biological indicator analysis were used to examine these patterns. Chironomidae was the most abundant family (>60%) in the upper mainstem river and stream sites. Stream sites were positively associated with CCA axis 2, being characterised by high turbidity and lower pH, salinity, phosphate concentration, channel width and canopy cover. Canopy cover, channel width, substrate embeddedness, phosphate concentration, pH, salinity and turbidity all had a significant effect on macroinvertebrate community composition. Using CCA variation partitioning, water quality was, however, a better predictor of benthic macroinvertebrate composition than sediment chemical conditions. Furthermore, our results suggest that seasonality had little effect on structuring benthic macroinvertebrate communities in this south-eastern zone of South Africa, despite clear changes in sediment chemistry. This likely reflects the relative lack of major variability in water chemistry compared to sediment chemistry between seasons and the relatively muted variability in precipitation between seasons than the more classic Austral temperate climates.
    Matched MeSH terms: Water Pollution
  20. Fulltext Metabolites Re-programming and Physiological Changes Induced in Scenedesmus regularis under Nitrate Treatment
    Ma NL, Aziz A, Teh KY, Lam SS, Cha TS
    Sci Rep, 2018 06 27;8(1):9746.
    PMID: 29950688 DOI: 10.1038/s41598-018-27894-0
    Nitrate is required to maintain the growth and metabolism of plant and animals. Nevertheless, in excess amount such as polluted water, its concentration can be harmful to living organisms such as microalgae. Recently, studies on microalgae response towards nutrient fluctuation are usually limited to lipid accumulation for the production of biofuels, disregarding the other potential of microalgae to be used in wastewater treatments and as source of important metabolites. Our study therefore captures the need to investigate overall metabolite changes via NMR spectroscopy approach coupled with multivariate data to understand the complex molecular process under high (4X) and low (1/4X) concentrations of nitrate ([Formula: see text]). NMR spectra with the aid of chemometric analysis revealed contrasting metabolites makeup under abundance and limited nitrate treatment. By using NMR technique, 43 types of metabolites and 8 types of fatty acid chains were detected. Nevertheless, only 20 key changes were observed and 16 were down regulated in limited nitrate condition. This paper has demonstrated the feasibility of NMR-based metabolomics approach to study the physiological impact of changing environment such as pollution to the implications for growth and productivity of microalgae population.
    Matched MeSH terms: Water Pollution
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links