Removal of Arsenic in Groundwater Using Fe(III) Oxyhydroxide Coated Sand: A Case Study in Mekong Delta, Vietnam

Because of its threat to the quality of freshwater resources and human health, arsenic (As) pollution is important to scientific communities and policymakers around the world. The Mekong Delta, Vietnam, is one hotspot of As pollution. Its risk assessment of different environmental components has been well documented; however, very few studies focus on As removal techniques. Considering this information gap, this study aimed to investigate the performance of an innovative and low-cost treatment system using Fe(III)-oxyhydroxide (FeOOH) coated sand to remove As(III) from aqueous solution. Batch and column experiments were conducted at a laboratory scale in order to study removal kinetics and efficiency. Experimental results indicated that the adsorption isotherm of As(III) on FeOOH coated sand using Langmuir and Freundlich models have high regression factors of 0.987 and 0.991, respectively. The batch adsorption experiment revealed that contact time was approximately 8 h for rough saturation (kinetic test). The concentration of As(III) in effluents at flow rates of 0.6 L/h, 0.9 L/h, and 1.8 L/h ranged from 1.1 µg/L to 1.7 µg/L. Results from this study indicated that FeOOH coated sand columns were effective in removing As(III) from water, with a removal efficiency of 99.1%. Ultimately, FeOOH coated sand filtration could be a potential treatment system to reduce As(III) in the domestic water supply in remote areas of the Vietnamese Mekong Delta.

Perception-based Assessment of Ecosystem Services of Abijata-Shalla National Park Wetlands in the Central Rift Valley of Ethiopia

Abijata-Shalla Park was established as one of Ethiopia's national parks to safeguard wetlands and ecosystem services (ESs). Some of the ESs that are offered by the wetlands are currently depleting and disappearing rather than being protected. Understanding the drivers behind these changes can help individuals and policymakers design mitigation measures. The objective of this case was to assess ESs and the drivers of change with highlighting on the Abijata wetland. In addition to a household survey and group discussion, personal interviews and field observation were employed to collect data. Using these data, the various ESs were assessed and ranked from 1-10 according to local perception. Grading scales such as very high (−2), high (−1), neutral (0), low (+1), and very low (+2) were employed to analyse the drivers of ESs change. Analyses of the study revealed that some of the ESs, including fish, papyrus, water reeds, hunting and spiritual services, existed before 1991, but have since disappeared from the site. Twenty ESs are available; 11 services pertain to provisioning, followed by 4 regulating, 3 cultural and 2 supporting services. Wetland for cultivation ranked highest, followed by domestic water supply and pasture. All services, with the exception of arable land and pasture, are on the decline. Water abstraction is the primary driver of ESs change, followed by population growth and deforestation. The park existed as a "paper park." Water withdrawals from the Ziway-Shalla sub-basin should be restricted. Instead, focus on water conservation strategies to make better use of abstracted water.

Impact of climate change on domestic water accessibility in Bamenda III Sub-Division, North West region, Cameroon

The effects of climate change are felt most at the household level, when taps and springs run dry for several weeks or months, forcing people to access potable water from doubtful sources. There has been an increase in the population of Bamenda III without a proportionate increase in the water supply capacity. This has resulted in severe water crises, even though Bamenda III municipality has water supplies from the Council, Community, CAMWATER, natural springs and streams, wells and boreholes. Household data on water accessibility against a backdrop of a changing climate was collected using 269 questionnaires to assess perceptions on the state of water resources and climate. Rainfall data were collected from 1963-2019 and results revealed that mean annual rainfall is at 182.52 mm, with a standard deviation of 29.16 and a Coefficient of Variation of 15.69%, while the mean Standardized Precipitation Index is -0.07 (mild dryness), and rainfall has reduced by -2.07 mm from 1963-2019. The population attributed problems of water accessibility to climate change, urbanization and poor water governance. It is recommended that sustainable water management through Nature-based Solutions and Ecosystem-based Adaptation should be implemented from the watershed to the community level.

Investigating the Attitude of Domestic Water Use in Urban and Rural Households in South Africa

South Africa is a semi-arid, water-stressed country. Adequate measures should be put in place to prevent water wastage. This paper aims to assess domestic water wastage and determine the proper attitude towards household water management in rural and urban communities in South Africa. This study was conceptualised in two stages. Firstly, critical observations were used to examine the attitude of households towards water usage in both urban and rural communities (Durban and Thohoyandou, respectively). Secondly, structured questionnaires and interviews were used to identify the factors that influenced the participants’ attitudes towards domestic water usage. This study concludes that, irrespective of the literacy level, accessibility to limited water supply, information available through advertisements about water scarcity, and better water management in an urban community, the rural community has a better attitude towards domestic water usage and water management. The result (83.3%) also indicated that the rural community strongly agreed to be water savers in their homes. However, in the urban community, the results from the participants were somewhat evenly distributed; the participants strongly agreed and disagreed at 36.2% and 32.2%, respectively. Other results of the study also showed that variables such as family upbringing, inaccessibility of domestic water, and advertisement play a major role in influencing the attitude of the rural community to water usage. These variables were statistically significant at p < 0.001. However, the immediate environment was shown to be not statistically significant at p < 0.911. Based on the study results, it is recommended that households should be encouraged to generate greywater collection systems to reduce water use and improve water reuse. The government could introduce a rationed allocation (shedding) of domestic water in urban communities to draw attention to the prevalence of water scarcity in the nation.

Atypical and dual biotypes variant of virulent SA-NAG-Vibrio cholerae: an evidence of emerging/evolving patho-significant strain in municipal domestic water sources

Introduction and purpose The recent cholera spread, new cases, and fatality continue to arouse concern in public health systems; however, interventions on control is at its peak yet statistics show continuous report. This study characterized atypical and patho-significant environmental Vibrio cholerae retrieved from ground/surface/domestic water in rural-urban-sub-urban locations of Amathole District municipality and Chris Hani District municipality, Eastern Cape Province, South Africa. Methods Domestic/surface water was sampled and 759 presumptive V. cholerae isolates were retrieved using standard microbiological methods. Virulence phenotypic test: toxin co-regulated pili (tcp), choleragen red, protease production, lecithinase production, and lipase test were conducted. Serotyping using polyvalent antisera (Bengal and Ogawa/Inaba/Hikojima) and molecular typing: 16SrRNA, OmpW, serogroup (Vc-O1/O139), biotype (tcpAClas/El Tor, HlyAClas/El Tor, rstRClas/El Tor, RS1, rtxA, rtxC), and virulence (ctxA, ctxB, zot, ace, cep, prt, toxR, hlyA) genes were targeted. Result Result of 16SrRNA typing confirmed 508 (66.9%) while OmpW detected/confirmed 61 (12.01%) V. cholerae strains. Phenotypic-biotyping scheme showed positive test to polymyxin B (68.9%), Voges proskauer (6.6%), and Bengal serology (11.5%). Whereas Vc-O1/O139 was negative, yet two of the isolates harbored the cholera toxin with a gene-type ctxB and hlyAClas: 2/61, revealing atypical/unusual/dual biotype phenotypic/genotypic features. Other potential atypical genotypes detected include rstR: 7/61, Cep: 15/61, ace: 20/61, hlyAElTor: 53/61, rtxA: 30/61, rtxC: 11/61, and prtV: 15/61 respectively. Conclusion Although additional patho-significant/virulent genotypes associated with epidemic/sporadic cholera cases were detected, an advanced, bioinformatics, and post-molecular evaluation is necessary. Such stride possesses potential to adequately minimize future cholera cases associated with dynamic/atypical environmental V. cholerae strains.

Estimation of Groundwater Recharge in Kumamoto Area, Japan in 2016 by Mapping Land Cover Using GIS Data and SPOT 6/7 Satellite Images

Agricultural fields, grasslands, and forests are very important areas for groundwater recharge. However, these types of land cover in the Kumamoto area, Japan, were damaged by the Kumamoto earthquake and heavy rains in 2016. In this region, where groundwater provides almost 100% of the domestic water supply for a population of about 1 million, quantitative evaluation of changes in groundwater recharge due to land cover changes induced by natural disasters is important for the sustainable use of groundwater in the future. The objective of this study was to create a land cover map and estimate the groundwater recharge in 2016. Geographic information system (GIS) data and SPOT 6/7 satellite images were used to classify the Kumamoto area into nine categories. The maximum likelihood classifier of supervised classification was applied in ENVI 5.6. Eventually, the map was cleaned up with a 21 × 21 kernel filter, which is larger than the common size of 3 × 3. The created land cover map showed good performance of the larger filter size and sufficient validity, with overall accuracy of 91.7% and a kappa coefficient of 0.88. The estimated total groundwater recharge amount reached 757.56 million m3. However, if areas of paddy field, grassland, and forest had not been reduced due to the natural disasters, it is estimated that the total groundwater recharge amount would have been 759.86 million m3, meaning a decrease of 2.30 million m3 in total. The decrease of 2.13 million m3 in the paddy fields is temporary, because the paddy fields and irrigation channels have been improved and the recharge amount will recover. On the other hand, since the topsoil on the landslide scars will not recover easily in natural conditions, it is expected to take at least 100 years for the groundwater recharge to return to its original state. The recharge amount was estimated to decrease by 0.17 million m3 due to landslides. This amount is quite small compared to the total recharge amount. However, since the reduced recharge amount accounts for the annual water consumption for 1362 people, and 12.1% of the recharge decrease of 1.41 million m3 each year to fiscal year 2024 is expected by municipalities, we conclude that efforts should be made to compensate for the reduced amount due to the disasters.

Ecological Governance and the Sustainability of Rural Household Water Conservation Systems in the Savannah Region of Ghana

This chapter examined the link between ecological governance and water conservation as sustainable pathways for enhancing rural livelihoods in the Savannah Region. Designs adopted were post-positivist and cross-sectional. Probability sampling techniques were used to sample 450 household and official respondents. Questionnaires were administered, while descriptive statistics and chi-square test were utilised to analyse the data. Findings showed significant relationship between conservation initiatives, finance, rehabilitation/maintenance, and gender inclusion and domestic water conservation. Therefore, with commitment to maintenance, funding, and gender inclusion in water decisions, there is the likely for water to be locally sustainable in rural communities of the region. Democratic, decentralised, and participatory approaches to ecological governance and empowerment of the local communities are recommended as essential preconditions for achieving ecologically self-governing communities and sustaining domestic water systems in the rural areas of the region.

The influence of water source protection zone delimitation on development in Huanren Manchu Autonomous County

Under the background of rapid urbanization and industrialization development, in order to satisfy the increasing demand of residents for domestic water, the establishment of water source protection zone is the most effective way to protect water resources at present. However, the influence on the social and economic development could not be ignored. The article analyzes the influence of the delimitation of water source protection zone on economy such as ecological migration, urban municipal pipe network construction, rural drinking water and urban water supply. The impact on economy like industrial enterprises, agricultural planting, livestock industry, aquaculture, tourist industry were also mentioned. The article triggers the exploration of the way to realize the coordination and sustainable development of economy, society, resources and environment

Knowledge, Attitude & Practices towards Safe Water, Sanitation and Hygiene

Affordable and sustainable access to water, sanitation and hygiene (WASH) is a key public health issue and focus of Sustainable Development Goals. Literature showed that households having prior knowledge and an acceptable attitude towards WASH practices have less number of diseases. The main objective of the study was to explore the level of respondents' knowledge, attitude and practices towards safe Water, Sanitation and Hygiene Conditions in South Punjab, Pakistan. The study was mixed-method research. SPSS also applied, and results demonstrate that there was very lack of knowledge about safe WASH practices; the majority of respondents have a traditional attitude. Whereas only 27.3% of respondents have always access to safe drinking water, 96% of respondents were not using any domestic water treatment method, 22.9% were defecating in the open, and the percentage of always handwashing with soap was found to only 29.6%. Social Mobilization programs along with government action to ensure safe WASH conditions are recommended.