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Fehrenbach GW, Murphy E, Pogue R, Carter F, Clifford E, Major I. Comprehensive analysis and assessment of exposure to enteric viruses and bacteria in shellfish. MARINE ENVIRONMENTAL RESEARCH 2024; 196:106404. [PMID: 38341981 DOI: 10.1016/j.marenvres.2024.106404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 01/30/2024] [Accepted: 02/07/2024] [Indexed: 02/13/2024]
Abstract
Shellfish species, including oysters, clams, and mussels, are extensively cultured in coastal waters. Its location is determined by factors such as nutrient availability, water temperature, tidal cycle, and the presence of contaminants such as Escherichia coli and enteric viruses. With the expansion and intensification of human activities at vicinities, the presence of anthropogenic contaminants has increased, threatening shellfish farms and consumer safety give the prevalent consumption of raw shellfish. This literature review aims to provide a comprehensive analysis of the dietary exposure and assess the risk associated with enteric viruses and bacteria detected in shellfish. The predominant bacteria and viruses detected in shellfish are reported, and the potential interrelation is discussed. The main characteristics of each contaminant and shellfish were reviewed for a more comprehensive understanding. To facilitate a direct estimation of exposure, the estimated daily intake (EDI) of bacteria was calculated based on the average levels of E. coli in shellfish, as reported in the literature. The mean daily ingestion of seafood in each of the five continents was considered. Asia exhibited the highest intake of contaminants, with an average of ±5.6 E. coli units/day.kg body weight in cockles. Simulations were conducted using recommended shellfish consumption levels established by state agencies, revealing significantly lower (p < 0.01) EDI for all continents compared to estimations based on recommended levels. This indicates a higher risk associated with healthy shellfish ingestion, potentially leading to increased intoxication incidents with a change in dietary habits. To promote a healthier lifestyle through increased shellfish consumptions, it is imperative to reduce the exposure of shellfish species to bacteria and enteric viruses. The conventional use of E. coli as the sole indicator for consumption safety and water quality in shellfish farms has been deemed insufficient. Instances where shellfish met E. coli limits established by state agencies were often found to be contaminated with human enteric viruses. Therefore, a holistic approach considering the entire production chain is necessary to support the shellfish industry and ensure food safety.
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Affiliation(s)
- Gustavo Waltzer Fehrenbach
- Materials Research Institute, Technological University of the Shannon, Midlands Campus, N37 HD68, Athlone, Ireland.
| | - Emma Murphy
- Materials Research Institute, Technological University of the Shannon, Midlands Campus, N37 HD68, Athlone, Ireland; LIFE - Health and Biosciences Research Institute, Technological University of the Shannon, Midwest Campus, V94 EC5T, Limerick, Ireland
| | - Robert Pogue
- Post-Graduate Program in Genomic Sciences and Biotechnology, Catholic University of Brasilia, 71966-700, Brasilia, Brazil
| | - Frank Carter
- Coney Island Shellfish Ltd., F91 YH56, Sligo, Ireland
| | - Eoghan Clifford
- School of Engineering, National University of Ireland Galway, H91 HX31, Galway, Ireland; Ryan Institute, National University of Ireland Galway, H91 HX31, Galway, Ireland
| | - Ian Major
- Materials Research Institute, Technological University of the Shannon, Midlands Campus, N37 HD68, Athlone, Ireland
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Schröder LS, Bhalerao AK, Kabir KH, Scheffran J, Schneider UA. Managing uphill cultivation under climate change - An assessment of adaptation decisions among tribal farmers in Nagaland state of India. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 349:119473. [PMID: 37939473 DOI: 10.1016/j.jenvman.2023.119473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 10/13/2023] [Accepted: 10/18/2023] [Indexed: 11/10/2023]
Abstract
Tribal farmers in the Himalayas are vulnerable to climatic changes, as their rain-fed cultivation systems, practiced on steep, sloping terrain, are susceptible to changes in rainfall while at the same time being the primary means of livelihood. Soil and water conservation practices (SWCP) can improve the resilience of these cultivation systems to adverse climatic conditions. However, little is known about adaptation within these tribal farming communities. This is the first empirical study on the adaptation decisions of tribal farmers in the Himalayan uplands of Northeast India. Starting from the analysis of future climate risks, we surveyed 372 tribal farmers in Nagaland state to analyze perceived climate and environmental changes in relation to socio-demographic factors. We estimate current adoption rates of SWCP together with farmers' goals and values and employ a binary logit model (BLM) to quantify the influence of diverse factors on adaptation decisions. Our results show that increases in temperatures and crop diseases were the most perceived changes by tribal farmers. Climate projections indicate that precipitation amount and intensity, along with temperatures, will increase towards the end of the century, underlining the importance of SWCP. However, all considered SWCP were employed by less than half of the tribal farmers. Adoption probabilities for all practices were significantly increased when farmers participated in agricultural training. After that, participation in a civil society organization, livestock ownership, high-altitude locations, and perceived increases in droughts were found to increase adoption probabilities significantly, while socio-demographic factors were of only minor importance. If the most effective factor was employed to all farmers, average adoption rates of SWCP could at least double. Adoption decisions were mainly motivated by improving livelihoods, sustaining natural resources, reducing workload, and preserving cultural aspects of cultivation. This research contributes to understanding adaptation decisions of tribal farmers and quantifies the untapped potential for climate change adaptation of marginalized and climate-vulnerable farming communities in mountain regions.
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Affiliation(s)
- Lea S Schröder
- Research Unit Sustainability and Climate Risks, Center for Earth System Research and Sustainability (CEN), University of Hamburg, Grindelberg 5, 20144, Hamburg, Germany.
| | - Amol K Bhalerao
- Training and Education Centre, Indian Council of Agricultural Research - Indian Veterinary Research Institute, Shivajinagar, Pune, 411 005, Maharashtra, India
| | - Khondokar H Kabir
- Research Unit Sustainability and Climate Risks, Center for Earth System Research and Sustainability (CEN), University of Hamburg, Grindelberg 5, 20144, Hamburg, Germany; School of Environmental Design and Rural Development, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada; Department of Agricultural Extension Education, Bangladesh Agricultural University, Mymensingh, 2202, Bangladesh
| | - Jürgen Scheffran
- Research Group Climate Change and Security, Institute of Geography, University of Hamburg, Grindelberg 5/7, 20144, Hamburg, Germany
| | - Uwe A Schneider
- Research Unit Sustainability and Climate Risks, Center for Earth System Research and Sustainability (CEN), University of Hamburg, Grindelberg 5, 20144, Hamburg, Germany
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Ekundayo TC, Ijabadeniyi OA, Igbinosa EO, Okoh AI. Using machine learning models to predict the effects of seasonal fluxes on Plesiomonas shigelloides population density. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 317:120734. [PMID: 36455774 DOI: 10.1016/j.envpol.2022.120734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
Seasonal variations (SVs) affect the population density (PD), fate, and fitness of pathogens in environmental water resources and the public health impacts. Therefore, this study is aimed at applying machine learning intelligence (MLI) to predict the impacts of SVs on P. shigelloides population density (PDP) in the aquatic milieu. Physicochemical events (PEs) and PDP from three rivers acquired via standard microbiological and instrumental techniques across seasons were fitted to MLI algorithms (linear regression (LR), multiple linear regression (MR), random forest (RF), gradient boosted machine (GBM), neural network (NN), K-nearest neighbour (KNN), boosted regression tree (BRT), extreme gradient boosting (XGB) regression, support vector regression (SVR), decision tree regression (DTR), M5 pruned regression (M5P), artificial neural network (ANN) regression (with one 10-node hidden layer (ANN10), two 6- and 4-node hidden layers (ANN64), and two 5- and 5-node hidden layers (ANN55)), and elastic net regression (ENR)) to assess the implications of the SVs of PEs on aquatic PDP. The results showed that SVs significantly influenced PDP and PEs in the water (p < 0.0001), exhibiting a site-specific pattern. While MLI algorithms predicted PDP with differing absolute flux magnitudes for the contributing variables, DTR predicted the highest PDP value of 1.707 log unit, followed by XGB (1.637 log unit), but XGB (mean-squared-error (MSE) = 0.0025; root-mean-squared-error (RMSE) = 0.0501; R2 =0.998; medium absolute deviation (MAD) = 0.0275) outperformed other models in terms of regression metrics. Temperature and total suspended solids (TSS) ranked first and second as significant factors in predicting PDP in 53.3% (8/15) and 40% (6/15), respectively, of the models, based on the RMSE loss after permutations. Additionally, season ranked third among the 7 models, and turbidity (TBS) ranked fourth at 26.7% (4/15), as the primary significant factor for predicting PDP in the aquatic milieu. The results of this investigation demonstrated that MLI predictive modelling techniques can promisingly be exploited to complement the repetitive laboratory-based monitoring of PDP and other pathogens, especially in low-resource settings, in response to seasonal fluxes and can provide insights into the potential public health risks of emerging pathogens and TSS pollution (e.g., nanoparticles and micro- and nanoplastics) in the aquatic milieu. The model outputs provide low-cost and effective early warning information to assist watershed managers and fish farmers in making appropriate decisions about water resource protection, aquaculture management, and sustainable public health protection.
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Affiliation(s)
- Temitope C Ekundayo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, Eastern Cape, South Africa; Department of Biotechnology and Food Science, Durban University of Technology, Steve Biko Campus, Steve Biko Rd, Musgrave, Berea, 4001, Durban, South Africa; Department of Microbiology, University of Medical Sciences, Ondo City, Ondo State, Nigeria.
| | - Oluwatosin A Ijabadeniyi
- Department of Biotechnology and Food Science, Durban University of Technology, Steve Biko Campus, Steve Biko Rd, Musgrave, Berea, 4001, Durban, South Africa
| | - Etinosa O Igbinosa
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, Eastern Cape, South Africa; Department of Microbiology, Faculty of Life Sciences University of Benin, Private Mail Bag 1154, Benin City, 300283, Nigeria
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, Eastern Cape, South Africa; Department of Environmental Health Sciences, College of Health Sciences, University of Sharjah, Sharjah, P.O. Box 27272, United Arab Emirates
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Haldar K, Kujawa-Roeleveld K, Hofstra N, Datta DK, Rijnaarts H. Microbial contamination in surface water and potential health risks for peri-urban farmers of the Bengal delta. Int J Hyg Environ Health 2022; 244:114002. [PMID: 35759864 DOI: 10.1016/j.ijheh.2022.114002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 06/08/2022] [Accepted: 06/11/2022] [Indexed: 11/18/2022]
Abstract
Ensuring safe irrigation practices is vital to sustaining food production in water-scarce delta areas. Bangladesh and many other developing countries discharge untreated wastewater into their surrounding surface water bodies, serving as the primary irrigation source. This indirect irrigation of wastewater is believed to pose threats to the farmers, consumers and market vendors and may also affect crop and soil quality. To assess the risk, peri-urban farmers who use surrounding water bodies of Khulna city, Bangladesh, for crop irrigation were selected for the study. The microbial and heavy metal concentrations were measured in water samples collected from various locations over different seasons. For heavy metals As, Co, Ni, Cd, Cr, Cu and Pb, concentrations were below the detection limit, whereas Al, Fe, Mn, Ti and Zn were present but below the FAO recommendation limit for safe irrigation. The mean concentrations of microbial parameters were above the thresholds of WHO guidelines for crop irrigation intended for human consumption. Significant temporal variations in Faecal Coliform, E. coli and Enterococcus concentrations in the water samples were observed. The annual risk of infection for farmers was determined using the screening-level Quantitative Microbial Risk Assessment (QMRA). The results indicated that the annual probability of infection with pathogenic E. coli in different seasons ranges between 5 × 10-3 to 5 × 10-2, above the WHO's acceptable threshold for annual risk of infection for safe water reuse in agriculture. During the farmers' survey, around 45% reported health-related issues and more than 26% reported suffering from water-borne diseases after getting in contact with polluted surface water. This illustrates the actuality of the risks in practice. To ensure safe irrigation, the health risks need to be reduced below the acceptable limits. Suggested technical measures include adequate treatment of wastewater before disposal into rivers and access to protective equipment for farmers. This should be complemented by raising awareness through education programs among farmers to reduce accidental ingestion.
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Affiliation(s)
- Kamonashish Haldar
- Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700AA, Wageningen, the Netherlands.
| | - Katarzyna Kujawa-Roeleveld
- Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700AA, Wageningen, the Netherlands
| | - Nynke Hofstra
- Water Systems and Global Change, Wageningen University and Research, P.O. Box 47, 6700AA, Wageningen, the Netherlands
| | - Dilip Kumar Datta
- Environmental Science Discipline, Khulna University, Khulna, 9208, Bangladesh
| | - Huub Rijnaarts
- Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700AA, Wageningen, the Netherlands
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Manley A, Collins AL, Joynes A, Mellander PE, Jordan P. Coupled steroid and phosphorus leaching from cattle slurry at lysimeter scale. JOURNAL OF CONTAMINANT HYDROLOGY 2022; 247:103979. [PMID: 35231779 DOI: 10.1016/j.jconhyd.2022.103979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 12/14/2021] [Accepted: 02/17/2022] [Indexed: 06/14/2023]
Abstract
Water quality degradation can be caused by excessive agricultural nutrient transfers from fertilised soils exposed to wet weather. Mitigation measures within the EU Nitrates Directive aim to reduce this pressure by including 'closed' fertiliser spreading periods during wet months. For organic fertilisers such as slurry and manure, this closed period requires sufficient on-farm winter storage and good weather conditions to relieve storage at the end of the period. Therefore, robust scientific evidence is needed to support the measure. Incidental nutrient transfers of recently applied organic fertilisers in wet weather can also be complicated by synchronous transfers from residual soil stores and tracing is required for risk assessments. The combination of nutrient monitoring and biomarker analyses may aid this and one such biomarker suite is faecal steroids. Accordingly, this study investigated the persistence of steroids and their association with phosphorus during leaching episodes. The focus was on the coupled behaviour of steroids and total phosphorus (TP) concentrations in sub-surface hydrological pathways. Cattle slurry was applied to monolith lysimeters either side of a closed period and concentrations of both steroids and TP were monitored in the leachate. The study showed no significant effect of the treatment (average p = 0.17), though tracer concentrations did significantly change over time (average p = 0.001). While the steroidal concentration ratio was validated for herbivorous faecal pollution in the leachate, there was a weak positive correlation between the steroids and TP. Further investigation at more natural scales (hillslope/catchment) is required to confirm tracer behaviours/correlations and to compliment this sub-surface pathway study.
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Affiliation(s)
- Amber Manley
- Sustainable Agriculture Sciences, Rothamsted Research, North Wyke, Okehampton, EX20 2SB, UK; Agricultural Catchments Programme, Department of Environment, Soils and Landuse, Teagasc, Johnstown Castle, Co. Wexford, Ireland; School of Geography and Environmental Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, UK.
| | - Adrian L Collins
- Sustainable Agriculture Sciences, Rothamsted Research, North Wyke, Okehampton, EX20 2SB, UK
| | - Adrian Joynes
- Sustainable Agriculture Sciences, Rothamsted Research, North Wyke, Okehampton, EX20 2SB, UK
| | - Per-Erik Mellander
- Agricultural Catchments Programme, Department of Environment, Soils and Landuse, Teagasc, Johnstown Castle, Co. Wexford, Ireland
| | - Phil Jordan
- School of Geography and Environmental Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, UK
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Liu G, Mamode Ally N, Dooly DD, Li Y, Boodhoo K, Neetoo H. A study on the effectiveness of a defined microbial consortium to enhance the microbiological safety of cattle manure. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:2614-2620. [PMID: 33063345 DOI: 10.1002/jsfa.10886] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/07/2020] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Animal manure frequently harbors pathogenic microorganisms such as Salmonella spp. and diarrheagenic Escherichia coli. A defined microbial consortium such as effective microorganisms (EM) can potentially be used as a biocontrol against manure-borne human pathogens such as Salmonella and pathogenic E. coli. The objective of the study was to investigate the efficacy of EM to decontaminate cattle manure. RESULTS EM was first characterized by enumeration and identification of lactic acid bacteria (LAB), yeasts, actinomycetes and phototrophic bacteria (PB). The population density of LAB, yeasts, actinomycetes and presumptive PB was 6.9, 5.2, 5.9 and 3.9 log CFU g-1 respectively. LAB and yeast isolates were molecularly confirmed as Lactobacillus plantarum and L. casei (LAB) and Yarrowia lipolytica, Rhodotorula mucilaginosa and Picha manshurica (yeasts) respectively. Culture-independent molecular analysis revealed the presence of additional species including L. parabuchneri and Enterococcus faecium (LAB) and bacterial spore-formers Bacillus cereus and Clostridium spp. Application of EM to fresh cattle manure, inoculated with ~5-6 log CFU g-1 of antibiotic-resistant strain of indicator organism E. coli ATCC 25922, resulted in complete elimination of the organism in 20 days, while survivors were still detected in the untreated counterpart. CONCLUSION EM can potentially be used for sustainable pathogen control in cattle manure for enhanced food safety and environmental health. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Guoxia Liu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | | | | | - Yin Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | | | - Hudaa Neetoo
- Faculty of Agriculture, University of Mauritius, Reduit, Mauritius
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Sonoda K, Hashimoto Y, Wang SL, Ban T. Copper and zinc in vineyard and orchard soils at millimeter vertical resolution. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 689:958-962. [PMID: 31280176 DOI: 10.1016/j.scitotenv.2019.06.486] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 06/19/2019] [Accepted: 06/28/2019] [Indexed: 06/09/2023]
Abstract
Intensive uses of agrochemicals and soil amendments often cause the elevation of Cu and Zn concentrations in vineyard (VY) and orchard soils. The concentration and speciation of Cu and Zn in the soils at millimeter resolution is critical to understanding the risk of transport of these metals via surface runoff and infiltration. The objective of this study was to investigate the concentration and chemical species of Zn and Cu in VY and persimmon (PS) soils at millimeter vertical resolution. The soils were collected with 5 mm increments down to 5 cm depth and with 5 cm increments down to 25 cm depth. The total concentration and chemical species of Zn and Cu were determined by total digestion and X-ray absorption fine structure (XAFS) spectroscopy, respectively. The Zn concentration of VY soil reached a maximum of 290 mg kg-1 at the uppermost layer of the profile (0.5-1.0 cm). The Cu concentration of VY soil reached a maximum of 201 mg kg-1 (10-15 cm). These Zn and Cu concentrations were greater than background levels. Zinc K-edge XAFS spectroscopy determined that the uppermost layer of VY soil (0-0.5 cm) contained 42% Zn associated with humus and lesser extent of Zn associated with gibbsite (37%) and kaolinite (21%). Zinc associated with humus was not observed in the VY soil profiles below 0.5 cm, whereas Zn associated with gibbsite and kaolinite contributed >83% of total Zn species. Copper K-edge XAFS spectroscopy determined the presence of Cu bonded with humus (40-67%) and Cu adsorbed on kaolinite (26-45%) in the entire soil profile. Our study found the remarkable variation of Cu and Zn concentration and speciation within several centimeters from the soil surface in vineyard and orchard landscapes.
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Affiliation(s)
- Kent Sonoda
- Department of Bioapplications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 1848588, Japan
| | - Yohey Hashimoto
- Department of Bioapplications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 1848588, Japan.
| | - Shan-Li Wang
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Rd, Da'an District, Taipei 10617, Taiwan
| | - Takuya Ban
- Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwaicho, Fuchu, Tokyo 1838509, Japan
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Discerning liability for contamination by poultry integrators and producers under US federal law. WORLD POULTRY SCI J 2019. [DOI: 10.1017/s0043933910000012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
Land degradation, particularly soil erosion, is currently a major challenge for Nepal. With a high rate of population growth, subsistence-based rural economy, and increasingly intense rainfall events in the monsoon season, Nepal is prone to several forms of land degradation, such as floods, landslides, and soil erosion. To understand the causes, impacts, and possible management options for soil erosion, a review on the causal factors, status, and amelioration measures for land degradation in Nepal was conducted based on recent information available in national and international journals and grey literature. Intense rainfall and conventional tillage practices coupled with poor soil structure and steep slopes are the main drivers of soil erosion. Soil erosion leads to losses in soil and crop productivity, pollution of land and water resources, and a loss of farm income. Strategies to manage erosion include mulching, cover cropping, contour farming, strip cropping, and conservation agriculture practices, along with bioengineering techniques. Land degradation issues are a prime policy focus in Nepal, including national three- and five-year plans. However, these policies have been generally ineffective in reducing soil erosion, landslides, and floods in relation to the set targets. Realistic plans need to be formulated in Nepal focusing more on capacity enhancement and local participation to actively influence land-degradation processes.
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Environmental Factors and the Microbial Quality of Urban Drinking Water in a Low-Income Country: The Case of Madagascar. WATER 2018. [DOI: 10.3390/w10101450] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Access to piped water is often limited to urban areas in low-income countries, and the microbiological quality of drinking water varies due to technical and environmental constraints. To analyse the parameters that modulate the contamination of these systems, this study examines 16 years of microbial quality data for water supplied in 32 urban areas of Madagascar. A discriminant statistical approach and agglomerative hierarchical clusters were applied to environmental and climatic data. The microbial contamination varied between sites from 3.3 to 17.5%, and 78% of the supply systems showed large variations between years or months. Agglomerative hierarchical clusters (AHCs) revealed four supply system profiles that share a similar bacteriological evolution. Heavy rainfall and dry periods sustained increasing contamination, as reflected in levels of spores of sulphite-reducing clostridia (SSRC) and/or total coliforms (TC). SSRC were dominant in three profiles, with faecal indicator bacteria (FIB) dominant in the other. Principal component analysis demonstrated the main drivers of contamination: type of water source, implemented treatment, location of the site, population growth, lack of protection, agriculture, urbanization/sanitation, and flooding threats. Contamination increased over the 16-year period, reaching alarming levels. The protection of water sources should be a concern for public authorities.
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Chen YM, Xu X, Jiao XG, Sui YY, Liu XB, Zhang JY, Zhou K, Zhang JM. Responses of Labile Organic Nitrogen Fractions and Enzyme Activities in eroded Mollisols After 8-year Manure Amendment. Sci Rep 2018; 8:14179. [PMID: 30242277 PMCID: PMC6155099 DOI: 10.1038/s41598-018-32649-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 09/12/2018] [Indexed: 11/16/2022] Open
Abstract
Soil erosion will cause a degradation in soil nitrogen supplying capacity (SNSC) and manure amendment is an effective way to restored eroded soils. Both labile fractions of soil organic N (SON) and N transformation enzymes are indicators for SNSC, but the effect of manure amendments on labile SON fractions and the relationship between labile SON fractions and enzyme activities remains unclear. In this study, five degrees of erosion were simulated in Mollisols (removal of 0, 5, 10, 20 and 30 cm of topsoil) to analyse the changes in labile SON fractions and nitrogen transformation enzyme activities after 8-year manure amendment. We found that soil total N (TN), labile SON fractions and enzyme activities all increased after manure amendments. The largest labile SON fraction was particle organic nitrogen (POM-N) and the second was light fraction organic nitrogen (LFOM-N), which accounted >60% for TN in total. Correlation analysis showed that both urease and protease activities were significantly correlated with POM-N, LFOM-N, microbial biomass N and dissolvable organic N, indicating that both urease and protease activities can be used to predict labile SON pools and enzyme activities worked similarly in indicating SNSC with labile SON fractions. Altogether, 8-year manure amendment could recover SNSC of lightly eroded Mollisols to natural levels, i.e. erosion depths at 5 cm and 10 cm; however, it is not able to recover SNSC in Mollisols suffering severe erosion.
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Affiliation(s)
- Yi-Min Chen
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, 150081, Harbin, China.,University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Xin Xu
- College of Agricultural Resources and Environment, Heilongjiang University, 150080, Harbin, China
| | - Xiao-Guang Jiao
- College of Agricultural Resources and Environment, Heilongjiang University, 150080, Harbin, China.
| | - Yue-Yu Sui
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, 150081, Harbin, China.
| | - Xiao-Bing Liu
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, 150081, Harbin, China
| | - Jin-Yuan Zhang
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, 150081, Harbin, China.,University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Ke Zhou
- College of Agricultural Resources and Environment, Heilongjiang University, 150080, Harbin, China
| | - Jiu-Ming Zhang
- Institute of Soil and Fertilizer and Environment Resources, Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China
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Two-stage vertical flow multi-soil-layering (MSL) technology for efficient removal of coliforms and human pathogens from domestic wastewater in rural areas under arid climate. Int J Hyg Environ Health 2018; 221:64-80. [DOI: 10.1016/j.ijheh.2017.10.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 09/04/2017] [Accepted: 10/08/2017] [Indexed: 11/17/2022]
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Marucci PL, Cubitto MA. Strategies for recovering of planktonic and sessile cells of Escherichia coli O157:H7 from freshwater environment. ENVIRONMENTAL MONITORING AND ASSESSMENT 2016; 188:432. [PMID: 27344557 DOI: 10.1007/s10661-016-5434-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Accepted: 06/14/2016] [Indexed: 06/06/2023]
Abstract
The experiments were performed with Escherichia coli O157:H7 EDL 933 in freshwater microcosms at 12 °C. At 35, 45, and 70 days, samples were taken and filtered through 0.45 μm membrane filters. The following alternatives were tested to evaluate the recovery percentage of injured cells: (1) selective media CHROMagar(™)O157 and chromID(™)O157:H7 agar, at 37 °C for 24 h; (2) tryptic soy agar supplemented with yeast extract (TSAE), incubated at 25 °C for 2 or 4 h, then transferred to CHROMagar(™)O157 or chromID(™)O157:H7 agar at 37 °C (TSAE2h-CHROM, TSAE4h-CHROM and TSAE2h-ID, TSAE4h-ID); (3) thin agar layer (TAL) method, TSAE was overlaid on CHROMagar(™)O157 or chromID(™)O157:H7 agar (TALCHROM and TALID, respectively) and incubated at 37 °C for 24 h; and (4) TALCHROM at 25 °C for 4 h, then continued up to complete 24 h at 37 °C (TALCHROM4h). Furthermore, the recovery of E. coli O157:H7 cells adhering to glass coverslips were evaluated to mimic biofilm conditions. The recovery percentages obtained from each alternative were calculated relative to TSAE counts. After 70 days, TSAE4h-CHROM and TALCHROM4h showed the highest recovery percentage (>90 %) from water microcosms. Despite the improved recovery of cell adhering to glass surfaces, the percentages obtained with TSAE4h-CHROM were low. Further studies for the recovery of biofilm-forming E. coli O157:H7 are required. Pre-incubation on TSAE at 25 °C for 4 h, combined with CHROMagar(™)O157, or by thin agar layer method (TALCHROM) enhanced significantly the recovery of viable cells of E. coli O157:H7 after prolonged stay in water microcosms.
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Affiliation(s)
- Patricia L Marucci
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, 8000, Bahía Blanca, Argentina
| | - María A Cubitto
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, 8000, Bahía Blanca, Argentina.
- Centro de Recursos Naturales Renovables de la Zona Semiárida (CERZOS, UNS-CONICET), Bahía Blanca, Argentina.
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Abia ALK, Ubomba-Jaswa E, Momba MNB. Impact of seasonal variation on Escherichia coli concentrations in the riverbed sediments in the Apies River, South Africa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 537:462-469. [PMID: 26318680 DOI: 10.1016/j.scitotenv.2015.07.132] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 07/27/2015] [Accepted: 07/27/2015] [Indexed: 06/04/2023]
Abstract
Many South Africans living in resource-poor settings with little or no access to pipe-borne water still rely on rivers as alternative water sources for drinking and other purposes. The poor microbial quality of such water bodies calls for appropriate monitoring. However, routine monitoring only takes into consideration the microbial quality of the water column, and does not include monitoring of the riverbed sediments for microbial pollution. This study sought to investigate the microbial quality of riverbed sediments in the Apies River, Gauteng Province, South Africa, using Escherichia coli as a faecal indicator organism and to investigate the impact of seasonal variation on its abundance. Weekly samples were collected at 10 sampling sites on the Apies River between May and August 2013 (dry season) and between January and February 2014 (wet season). E. coli was enumerated using the Colilert®-18 Quanti-Tray® 2000 system. All sites tested positive for E. coli. Wastewater treatment work effluents had the highest negative impact on the river water quality. Seasonal variations had an impact on the concentration of E. coli both in water and sediments with concentrations increasing during the wet season. A strong positive correlation was observed between temperature and the E. coli concentrations. We therefore conclude that the sediments of the Apies River are heavily polluted with faecal indicator bacteria and could also harbour other microorganisms including pathogens. The release of such pathogens into the water column as a result of the resuspension of sediments due to extreme events like floods or human activities could increase the health risk of the populations using the untreated river water for recreation and other household purposes. There is therefore an urgent need to reconsider and review the current South African guidelines for water quality monitoring to include sediments, so as to protect human health and other aquatic lives.
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Affiliation(s)
- Akebe Luther King Abia
- Department of Environmental, Water and Earth Science, Tshwane University of Technology, Arcadia Campus, 175 Nelson Mandela Drive, Pretoria 0001, South Africa.
| | - Eunice Ubomba-Jaswa
- Natural Resources and the Environment, CSIR, PO Box 395, Pretoria 0001, South Africa
| | - Maggy Ndombo Benteke Momba
- Department of Environmental, Water and Earth Science, Tshwane University of Technology, Arcadia Campus, 175 Nelson Mandela Drive, Pretoria 0001, South Africa.
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Sauco S, Gómez J, Barboza FR, Lercari D, Defeo O. Modified whole effluent toxicity test to assess and decouple wastewater effects from environmental gradients. PLoS One 2013; 8:e66285. [PMID: 23755304 PMCID: PMC3673937 DOI: 10.1371/journal.pone.0066285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 05/08/2013] [Indexed: 11/18/2022] Open
Abstract
Environmental gradients and wastewater discharges produce aggregated effects on marine populations, obscuring the detection of human impact. Classical assessment methods do not include environmental effects in toxicity tests designs, which could lead to incorrect conclusions. We proposed a modified Whole Effluent Toxicity test (mWET) that includes environmental gradients in addition to effluent dilutions, together with the application of Generalized Linear Mixed Models (GLMM) to assess and decouple those effects. We tested this approach, analyzing the lethal effects of wastewater on a marine sandy beach bivalve affected by an artificial canal freshwater discharge used for rice crops irrigation. To this end, we compared bivalve mortality between canal water dilutions (CWd) and salinity controls (SC: without canal water). CWd were prepared by diluting the water effluent (sampled during the pesticide application period) with artificial marine water. The salinity gradient was included in the design by achieving the same final salinities in both CWd and SC, allowing us to account for the effects of salinity by including this variable as a random factor in the GLMM. Our approach detected significantly higher mortalities in CWd, indicating potential toxic effects of the effluent discharge. mWET represents an improvement over the internationally standardized WET tests, since it considers environmental variability and uses appropriate statistical analyses.
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Affiliation(s)
- Sebastián Sauco
- UNDECIMAR, Departamento de Ecología y Evolución, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
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Goss MJ, Tubeileh A, Goorahoo D. A Review of the Use of Organic Amendments and the Risk to Human Health. ADVANCES IN AGRONOMY 2013; 120. [PMCID: PMC7173535 DOI: 10.1016/b978-0-12-407686-0.00005-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Historically, organic amendments—organic wastes—have been the main source of plant nutrients, especially N. Their use allows better management of often-finite resources to counter changes in soils that result from essential practices for crop production. Organic amendments provide macro- and micronutrients, including carbon for the restoration of soil physical and chemical properties. Challenges from the use of organic amendments arise from the presence of heavy metals and the inability to control the transformations required to convert the organic forms of N and P into the minerals available to crops, and particularly to minimize the losses of these nutrients in forms that may present a threat to human health. Animal manure and sewage biosolids, the organic amendments in greatest abundance, contain components that can be hazardous to human health, other animals and plants. Pathogens pose an immediate threat. Antibiotics, other pharmaceuticals and naturally produced hormones may pose a threat if they increase the number of zoonotic disease organisms that are resistant to multiple antimicrobial drugs or interfere with reproductive processes. Some approaches aimed at limiting N losses (e.g. covered liquid or slurry storage, rapid incorporation into the soil, timing applications to minimize delay before plant uptake) also tend to favor survival of pathogens. Risks to human health, through the food chain and drinking water, from the pathogens, antibiotics and hormonal substances that may be present in organic amendments can be reduced by treatment before land application, such as in the case of sewage biosolids. Other sources, such as livestock and poultry manures, are largely managed by ensuring that they are applied at the rate, time and place most appropriate to the crops and soils. A more holistic approach to management is required as intensification of agriculture increases.
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Affiliation(s)
- Michael J. Goss
- University of Guelph, Kemptville Campus, Kemptville, ON, Canada
- Corresponding author: E-mail:
| | - Ashraf Tubeileh
- University of Guelph, Kemptville Campus, Kemptville, ON, Canada
| | - Dave Goorahoo
- Plant Science Department, California State University, Fresno, CA, USA
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Ingram DT, Patel J, Sharma M. Effect of repeated irrigation with water containing varying levels of total organic carbon on the persistence of Escherichia coli O157:H7 on baby spinach. J Food Prot 2011; 74:709-17. [PMID: 21549040 DOI: 10.4315/0362-028x.jfp-10-426] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The California lettuce and leafy greens industry has adopted the Leafy Greens Marketing Agreement (LGMA), which allows for 126 most-probable-number (MPN) Escherichia coli per 100 ml in irrigation water. Repeat irrigation of baby spinach plants with water containing E. coli O157:H7 and different levels of total organic carbon (TOC) was used to determine the epiphytic survival of E. coli O157:H7. Three irrigation treatments (0 ppm of TOC, 12 or 15 ppm of TOC, and 120 or 150 ppm of TOC) were prepared with bovine manure containing E. coli O157:H7 at either low (0 to 1 log CFU/100 ml) or high (5 to 6 log CFU/100 ml) populations, and sprayed onto baby spinach plants in growth chambers by using a fine-mist airbrush. MPN and direct plating techniques were used to determine the E. coli O157:H7 populations on the aerial plant tissue. Plants irrigated with high E. coli O157:H7 populations, regardless of TOC levels, showed a 3-log reduction within the first 24 h. Low levels of E. coli O157:H7 were observed for up to 16 days on all TOC treatments, ranging from 76.4 MPN per plant (day 1) to 0.40 MPN per plant (day 16). No viable cells were detected on spinach tissue 24 h after irrigation with water containing fewer than 126 CFU/100 ml E. coli O157:H7. Under growth chamber conditions in this study, E. coli O157:H7 populations in irrigation water that complies with the LGMA standards will not persist for more than 24 h when applied onto foliar surfaces of spinach plants.
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Affiliation(s)
- David T Ingram
- U.S. Department of Agriculture, Agricultural Research Service, Henry A. Wallace Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Building 201, BARC-East, 10300 Baltimore Avenue, Beltsville, Maryland 20705, USA
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Derlet RW. Backpacking in Yosemite and Kings Canyon National Parks and neighboring wilderness areas: how safe is the water to drink? J Travel Med 2008; 15:209-15. [PMID: 18666919 DOI: 10.1111/j.1708-8305.2008.00201.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The objective of this study was to determine the risk of acquiring disease from popular Sierra Nevada wilderness area lakes and streams. This study examines the relative risk factors for harmful waterborne microorganisms using coliforms as an indicator. METHODS Water was collected in the backcountry Yosemite and Kings Canyon National Parks and neighboring wilderness areas. A total of 72 sites from lakes or streams were selected to statistically differentiate the risk categories: (1) natural areas rarely visited by humans or domestic animals; (2) human day use-only areas; (3) high use by backpackers; (4) high use by pack animals; and (5) cattle- and sheep-grazing tracts. Water was collected in sterile test tubes and Millipore coliform samplers during the summer of 2006. Water was analyzed at the university microbiology lab, where bacteria were harvested and then subjected to analysis using standardized techniques. Statistical analysis to compare site categories was performed using Fisher's exact test. RESULTS Coliforms were found in none of the 13 wild sites, none of the 12 day hike sites, and only 3 of 18 backpacker sites (17%). In contrast, 14 of 20 sites (70%) with pack animal traffic yielded coliforms, and all 9 sites (100%) below the cattle-grazing areas grew coliforms. Differences between backpacker versus cattle or pack areas were significant, p <or= 0.05. All samples grew normal aquatic bacteria. Sites below cattle grazing and pack animal use tended to have more total heterotrophic bacteria. CONCLUSIONS Alpine wilderness water below cattle areas used by pack animals is at risk for containing coliform organisms. Water from wild, day hike, or backpack areas showed far less risk for coliforms.
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Affiliation(s)
- Robert W Derlet
- Department of Emergency Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA.
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Derlet RW, Ger KA, Richards JR, Carlson JR. Risk Factors for Coliform Bacteria in Backcountry Lakes and Streams in the Sierra Nevada Mountains: A 5-Year Study. Wilderness Environ Med 2008; 19:82-90. [DOI: 10.1580/07-weme-or-1511.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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