Water SA最新文献_第9页

Crop response and water productivity of sunflower (Helianthus annuus L.) drip-irrigated with magnetically treated and non-magnetically treated water with variable salinity 变盐度磁化水和非磁化水滴灌向日葵的作物响应和水分生产力

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2022-01-26 DOI: 10.17159/wsa/2022.v48.i1.3888

Mohsen Dastorani, Mohammad Albaji, Saeed Boroomand Nasab

{"title":"Crop response and water productivity of sunflower (Helianthus annuus L.) drip-irrigated with magnetically treated and non-magnetically treated water with variable salinity","authors":"Mohsen Dastorani, Mohammad Albaji, Saeed Boroomand Nasab","doi":"10.17159/wsa/2022.v48.i1.3888","DOIUrl":"https://doi.org/10.17159/wsa/2022.v48.i1.3888","url":null,"abstract":"To compare the effect of magnetic drip irrigation and conventional irrigation with different salinity levels on water productivity and yield of sunflower (Helianthus annuus L.), a factorial experiment was conducted using a completely randomized design with 6 treatments and 3 replicates at the Research Station of the Faculty of Water Sciences Engineering, Shahid Chamran University of Ahvaz, Iran. The experiment was executed over the crop year 2018–19. The treatment variables consisted of 2 types of water (magnetically treated and non-magnetically treated) and 3 salinity levels (Karun River water (S1), 4 dS/m (S2), and 6 dS/m (S3)). The use of magnetically treated irrigation water increased the biomass water use efficiency, and the weight of 100 seeds by 13.9%, and 5.48%, respectively. With the conventional irrigation method, increased salinity reduced the seed yield. The highest seed yield and irrigation water productivity were observed at 4 459 kg/ha and 0.73 kg/m3 for grain yield at a water salinity level of S1 (the control treatment). The application of water with salinity of 4 dS/m and 6 dS/m (S2 and S3) caused a reduction in seed yield by 9.3 and 21.8%, respectively, in comparison to that of the control treatment. Moreover, irrigation water productivity for the biomass yield decreased by 14.57 and 29.23%, respectively. Based on the results of this study, the use of magnetically treated water can reduce the effects of salinity stress under conditions of salt stress. Therefore, magnetically treated water can increase the yield and productivity of irrigation water.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"18 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72727881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Integration of complete elemental mass-balanced stoichiometry and aqueous phase chemistry for bioprocess modelling of liquid and solid waste treatment systems – Part 4: Aligning the modelled and measured aqueous phases 液体和固体废物处理系统的生物过程建模用完全元素质量平衡化学计量学和水相化学的集成。第4部分:校正模拟和测量的水相

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2022-01-26 DOI: 10.17159/wsa/2022.v48.i1.3322

GA Ekama, CJ Brouckaert, BM Brouckaert

{"title":"Integration of complete elemental mass-balanced stoichiometry and aqueous phase chemistry for bioprocess modelling of liquid and solid waste treatment systems – Part 4: Aligning the modelled and measured aqueous phases","authors":"GA Ekama, CJ Brouckaert, BM Brouckaert","doi":"10.17159/wsa/2022.v48.i1.3322","DOIUrl":"https://doi.org/10.17159/wsa/2022.v48.i1.3322","url":null,"abstract":"Completely mass-balanced biological, physical and chemical process stoichiometry ensures that the CHONPS material and charge content entering and exiting bioprocess system models is conserved, which is a requirement for pH prediction in integrated physical, chemical and biological process models. Bioprocesses transform the material content from reactants to products, exchanging material between the aqueous, gaseous and solid phases, which cause pH changes in the aqueous phase. By measuring the material content of the aqueous phase, the progress of bioprocesses can be monitored. Alkalinity is an important aqueous-phase property that can be used to track aqueous-phase changes caused by physical, chemical and biological processes. Alkalinity is a stoichiometry property of the components in solution (i.e., a linear function of the amounts present). Its uptake from, and release to, the aqueous phase can both be modelled with bioprocess stoichiometry, and measured in physical bioprocess systems, and so aid in linking the modelled and measured aqueous-phase compositions. Changes in the concentrations of components containing the elements C, H, O, N, P and S result in changes in six weak acid/bases systems in the aqueous phase, all of which affect the total alkalinity. These are: inorganic carbon (IC), ortho-phosphate (OP), free and saline ammonia (FSA), volatile fatty acids (VFA), free and saline sulphide (FSS) and the water itself. Characterization of the aqueous phase to quantify the material content of the aqueous phase containing these six weak acid/base systems using the 5-point titration method is described. While several alkalinity titration based methods are available for anaerobic digestion bioprocess monitoring, only the 5-point titration is sufficiently accurate for aqueous-phase characterization to quantify the aqueous-material content for pH prediction in bioprocess models.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"290 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76434663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Smallholder farmer coping and adaptation strategies for agricultural water use during drought periods in the Overberg and West Coast Districts, Western Cape, South Africa 南非西开普省奥弗伯格和西海岸地区小农干旱期间农业用水的应对和适应策略

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2022-01-26 DOI: 10.17159/wsa/2022.v48.i1.3846

Olwethu Pili, Bongani Ncube

{"title":"Smallholder farmer coping and adaptation strategies for agricultural water use during drought periods in the Overberg and West Coast Districts, Western Cape, South Africa","authors":"Olwethu Pili, Bongani Ncube","doi":"10.17159/wsa/2022.v48.i1.3846","DOIUrl":"https://doi.org/10.17159/wsa/2022.v48.i1.3846","url":null,"abstract":"Drought is one of the most significant disasters affecting farm productivity in South Africa, with the Western Cape Province among the most affected areas. Smallholder farmers usually suffer the most due to limited resources. The study identified agricultural water use coping and adaptation strategies adopted by both crop and livestock smallholder farmers in the West Coast and Overberg districts during the recent 2015–2018 drought. Interviews were conducted with 100 smallholder farmers and 11 focus group discussions were held in the two districts. Quantitative data were analysed using the Statistical Package for Social Sciences, while qualitative data were analysed using Atlas.ti. Furthermore, the Hyogo Framework of Action was used to analyse the support that smallholder farmers had received and to understand how smallholder farmers could be effectively supported to promote the adoption of proactive strategies to deal with drought in the short and long term. It was found that the 2015–2018 drought occurred when smallholder farmers from both districts were least expecting it and were unprepared. In the West Coast District, the main coping strategies included using borehole water and selling livestock. In the Overberg District, smallholder farmers coped by purchasing fodder and transporting water from sources such as the river and dam to the farms. Several smallholder farmers in both districts did not implement any adaptation strategies. They were largely unaware of proactive agricultural water use strategies that could bolster their resilience to drought. Recommendations for the future include the adoption of drip irrigation, mulching, growing vegetables with shorter growing periods and changing planting dates. For livestock farmers, adaptation strategies include drilling boreholes and grazing management. There is also a need for early warning systems to improve the drought preparedness of smallholder farmers.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88980459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

The effects of dry versus wet season on the performance of a wastewater treatment plant in North West Province, South Africa 干湿季节对南非西北省污水处理厂性能的影响

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2022-01-26 DOI: 10.17159/wsa/2022.v48.i1.3897

S Makuwa, M Tlou, E Fosso-Kankeu, E Green

{"title":"The effects of dry versus wet season on the performance of a wastewater treatment plant in North West Province, South Africa","authors":"S Makuwa, M Tlou, E Fosso-Kankeu, E Green","doi":"10.17159/wsa/2022.v48.i1.3897","DOIUrl":"https://doi.org/10.17159/wsa/2022.v48.i1.3897","url":null,"abstract":"The study was conducted at a wastewater treatment plant (WWTP) in the North West Province of South Africa (SA), to investigate the effect of seasonal variations of rainfall and temperature on the fate of Escherichia coli (E. coli) and on chemical parameters. Both seasons showed variations in terms of rainfall levels and temperature. The average temperatures measured at the final effluent were 14 and 22°C for the dry and wet season, while the rainfall averages ranged between 0.0 and 69.0 mm and 16.0 and 258.9 mm for the dry and wet season, respectively. The impact of rainfall within the two seasons presented a variation in the plant inflow rate of 34 000 and 48 000 m3 during the dry and wet season, respectively. Higher E. coli concentrations were detected before and after chlorination in the wet season (1.86 x 105 and 8.40 x 101 MPN/100 mL) than in the dry season (2.26 x 104 and 5.10 x 101 MPN/100 mL). The recorded values for the chemical parameters in the dry and wet season were within the following ranges: ammonia (0.27 and 3.68 mg/L), chemical oxygen demand (COD) (29.53 and 22.10 mg/L), nitrate (9.21 and 2.40 mg/L) and ortho-phosphate (0.46 and 0.39 mg/L). Though the detections of these indicator parameters were affected differently by the seasonal variations, it is important to note that the efficiency of the WWTP in reducing these indicator parameters proved to be consistent across all seasons, except in the case of ammonia and nitrate. The majority of the studied parameters showed effective compliance when measured against SA regulatory standards (general limits) in both the dry and wet season, with the exception of ammonia during the wet season.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"21 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74830060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Integration of complete elemental mass-balanced stoichiometry and aqueous-phase chemistry for bioprocess modelling of liquid and solid waste treatment systems − Part 3: Measuring the organics composition 用于液体和固体废物处理系统的生物过程建模的完全元素质量平衡化学计量学和水相化学的集成-第3部分:测量有机物组成

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2022-01-26 DOI: 10.17159/wsa/2022.v48.i1.3321

GA Ekama, CJ Brouckaert

{"title":"Integration of complete elemental mass-balanced stoichiometry and aqueous-phase chemistry for bioprocess modelling of liquid and solid waste treatment systems − Part 3: Measuring the organics composition","authors":"GA Ekama, CJ Brouckaert","doi":"10.17159/wsa/2022.v48.i1.3321","DOIUrl":"https://doi.org/10.17159/wsa/2022.v48.i1.3321","url":null,"abstract":"Bioprocesses transform the components of the material entering single or multiple reactor systems from one kind to another without a change in total material exiting the system(s) in the solid, aqueous or gas phases. Provided that the correct measurements are made that can quantify the material content of the bioprocess products (outputs), the material content of the bioprocess reactants (inputs) can be determined from the bioprocess products via stoichiometry. Based on this principle of mass conservation, the augmented biomethane (AugBMP) and biosulphide (AugBSP) potential test procedures are proposed, which change the BMP from a stand-alone test to a bio-reactor on which a range of additional tests are made to determine the composition of biodegradable organics. The AugBSP, which is based on biological sulphate reduction, can replace the inaccurate gas measurements in the BMP with the more accurate aqueous sulphate and sulphide measurements. The suitability of these two procedures is evaluated from a theoretical and modelling perspective. The analytical tests required to determine the composition of influent organics, expressed as CxHyOzNaPbSc, are identified. Examples of the calculation procedure from the test results are given. It is concluded that the augmented BMP (AugBMP) and BSP (AugBSP) test procedures, supplemented by anaerobic digestion dynamic modelling, are as accurate as the analytical measurements for determining the composition of biodegradable organics, and also allow the hydrolysis rate of the biodegradable organics and the unbiodegradable fraction of the organics to be determined. Knowing these characteristics of organics fed to anaerobic digesters is important to predict the anaerobic digester performance and stability.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"80 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74773424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Deriving the maximum extent and hydroperiod of open water from Sentinel-2 imagery for global sustainability and biodiversity reporting for wetlands 从Sentinel-2卫星图像中提取开放水域的最大范围和水文周期，用于全球湿地可持续性和生物多样性报告

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2022-01-26 DOI: 10.17159/wsa/2022.v48.i1.3883

Heidi van Deventer, A Linström, JF Durand, L Naidoo, MA Cho

{"title":"Deriving the maximum extent and hydroperiod of open water from Sentinel-2 imagery for global sustainability and biodiversity reporting for wetlands","authors":"Heidi van Deventer, A Linström, JF Durand, L Naidoo, MA Cho","doi":"10.17159/wsa/2022.v48.i1.3883","DOIUrl":"https://doi.org/10.17159/wsa/2022.v48.i1.3883","url":null,"abstract":"The monitoring of wetland extent is a global imperative, considering loss of ecosystem services and conservation value. To date, the understanding of the variation in the extent of lacustrine (inundated) wetlands has been limited, based on intermittently available, coarse-scale imagery. The aim of this study was to assess the capabilities of the freely available Sentinel-2 sensor in monitoring inundated wetlands. In particular, to demonstrate the ability to determine the maximum extent of inundation for reporting on the Sustainable Development Goal (SDG) 6.6 (Clean Water and Sanitation) and SDG 15.1 (i.e., halting biodiversity loss), the functional diversity and the hydrological regime of depressions were explored in the Mpumalanga Lake District (MLD) of South Africa. Using the monthly inundation data derived from Sentinel-2 images between January 2016 and May 2018, the results showed that the maximum extent of open water can be successfully reported for SDG 6.6. Lacustrine wetlands constituted about 47 of the 416 (but 66% of the total areal extent of) depressions in the MLD, while others were predominantly palustrine (vegetated). The functional diversity varied from predominantly (61% of the extent of) inundated depressions to seasonally (3%) inundated depressions. The Sentinel-2 sensor was able to detect intra- and inter-annual variation of the extent of inundation, making it suitable to monitor these wetlands for global and climate change impacts.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"40 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86834212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Integration of complete elemental mass-balanced stoichiometry and aqueous-phase chemistry for bioprocess modelling of liquid and solid waste treatment systems – Part 5: Ionic speciation 液体和固体废物处理系统的生物过程建模用完全元素质量平衡化学计量学和水相化学的集成。第5部分:离子形态

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2022-01-26 DOI: 10.17159/wsa/2022.v48.i1.3738

CJ Brouckaert, BM Brouckaert, GA Ekama

引用次数: 1

Lessons learned from operating a pre-commercialisation field-testing platform for innovative non-sewered sanitation in Durban, South Africa 在南非德班运营创新无下水道卫生设施商业化前现场测试平台的经验教训

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2021-10-28 DOI: 10.17159/wsa/2021.v47.i4.3880

RC Sindall, R Cottingham, P Arumugam, SJ Mercer, C Sutherland, N Alcock, CA Buckley, G Gounden

{"title":"Lessons learned from operating a pre-commercialisation field-testing platform for innovative non-sewered sanitation in Durban, South Africa","authors":"RC Sindall, R Cottingham, P Arumugam, SJ Mercer, C Sutherland, N Alcock, CA Buckley, G Gounden","doi":"10.17159/wsa/2021.v47.i4.3880","DOIUrl":"https://doi.org/10.17159/wsa/2021.v47.i4.3880","url":null,"abstract":"The Engineering Field Testing Platform (EFTP) was designed to provide an opportunity for technology developers (TDs) to test non-sewered sanitation prototypes in the eThekwini Municipal Area (Durban), South Africa. Between 2017 and 2020, 15 sanitation systems were tested in informal settlements, peri-urban households, and other ‘real world’ settings. This paper illustrates the lessons learned from establishing and managing this testing platform. Costs and timelines for testing are dependent on several factors, including the aims of testing, the development stage of the prototype, whether testing takes place in a community or household setting and if a testing site is shared between prototypes. Timelines were routinely underestimated, particularly for community engagement and commissioning of prototypes to reach steady-state operation. Personnel accounted for more than half of the EFTP’s costs. The presence of the municipality as a platform partner was vital to the success of testing, both for gaining political support and for enabling access to testing sites. It is noted that working in communities, with test sites in public spaces, requires technical and social sensitivity to context. It was important to ensure testing supported future municipal decision-making on service provision, as well as longer-term development within communities. The high number of stakeholders, locally and internationally, raised management challenges common to any large project. However, the EFTP added value to TDs, the eThekwini Municipality, and communities requiring improved sanitation services; this was amplified through the platform approach.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"161 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88091308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Trace elements in groundwater near an abandoned mine tailings dam and health risk assessment (NE Zimbabwe) 废弃矿山尾矿坝附近地下水中的微量元素与健康风险评估(津巴布韦东北部)

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2021-10-28 DOI: 10.17159/wsa/2021.v47.i4.3851

Artwell Kanda, France Ncube, Peter Makumbe

引用次数: 2

Rainy season characteristics for the Luvuvhu River catchment, South Africa 南非鲁武胡河集水区的雨季特征

IF 1.5 4区环境科学与生态学

Water SA Pub Date : 2021-10-28 DOI: 10.17159/wsa/2021.v47.i4.3677

Fhulufhelo Phillis Tshililo, M. J. Savage, M. Moeletsi

{"title":"Rainy season characteristics for the Luvuvhu River catchment, South Africa","authors":"Fhulufhelo Phillis Tshililo, M. J. Savage, M. Moeletsi","doi":"10.17159/wsa/2021.v47.i4.3677","DOIUrl":"https://doi.org/10.17159/wsa/2021.v47.i4.3677","url":null,"abstract":"Maize is a staple crop in South Africa and is mainly grown under rain-fed conditions. Rain-fed agricultural production is heavily reliant on rainfall during the planting season. Information on rainy season characteristics is of utmost importance as it guides farmers in preparing for the upcoming season. The study investigated rainy season characteristics for the Luvuvhu River Catchment with reference to rain-fed maize production. Historical daily rainfall data were obtained from 12 weather stations for the period 1923–2015. Instant+ statistical software was used to compute onset, false onset, cessation and length of the rainy season. The trends in rainy season characteristics were analysed using the Spearman rank correlation test. Onset of the rainy season can be expected from the first week of October to the third week of January, while cessation can be expected from the first week of February to the first week of May. The length of the rainy season ranged from 67 to 203 days. Seasonal rainfall ranged from 182 to 1 535 mm. Phafuri, Sigonde, Phunda Maria and Folovhodwe had a higher probability of false onset. No significant changes in rainy season characteristics at a 5% level of significance were observed. There was a strong correlation between onset and length of the rainy season. Based on rainfall patterns only, Phafuri, Sigonde and Folovhodwe might not be suitable for maize production under the current climate. The most favourable sites for maize production within the catchment are Entabeni, Levubu, Lwamondo, Thathe, Tshiombo and Vreemedeling. The findings of this study have implications on agricultural activities and food security as maize is a staple crop in the Luvuvhu River catchment area. Information on rainy season characteristics may therefore help in strengthening food security.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"5 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74823061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1