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An integrative analytical model for the water-energy-food nexus: South Africa case study 全文
2020
Nhamo, Luxon | Mabhaudhi, T. | Mpandeli, Sylvester | Dickens, Chris | Nhemachena, Charles | Senzanje, Aidan | Naidoo, Dhesigen | Liphadzi, Stanley | Modi, Albert T.
An integrative analytical model for the water-energy-food nexus: South Africa case study 全文
2020
Nhamo, Luxon | Mabhaudhi, T. | Mpandeli, Sylvester | Dickens, Chris | Nhemachena, Charles | Senzanje, Aidan | Naidoo, Dhesigen | Liphadzi, Stanley | Modi, Albert T.
The missing link between cross-sectoral resource management and full-scale adoption of the water-energy-food (WEF) nexus has been the lack of analytical tools that provide evidence for policy and decision-making. This study defined WEF nexus sustainability indicators, from where an analytical model was developed to manage WEF resources in an integrated manner using the Analytic Hierarchy Process (AHP). The model established quantitative relationships among WEF sectors, simplifying the intricate interlinkages among resources, using South Africa as a case study. A spider graph was used to illustrate sector performance as related to others, whose management is viewed either as sustainable or unsustainable. The model was then applied to assess progress towards the Sustainable Development Goals in South Africa. The estimated integrated indices of 0.155 and 0.203 for 2015 and 2018, respectively, classify South Africa’s management of resources as marginally sustainable. The model is a decision support tool that highlights priority areas for intervention.
显示更多 [+] 显示较少 [-]An integrative analytical model for the water-energy-food nexus: South Africa case study 全文
2020
Nhamo, L. | Mabhaudhi, Tafadzwanashe | Mpandeli, S. | Dickens, Chris | Nhemachena, C. | Senzanje, Aidan | Naidoo, D. | Liphadzi, S. | Modi, Albert Thembinkosi
The missing link between cross-sectoral resource management and full-scale adoption of the water-energy-food (WEF) nexus has been the lack of analytical tools that provide evidence for policy and decision-making. This study defined WEF nexus sustainability indicators, from where an analytical model was developed to manage WEF resources in an integrated manner using the Analytic Hierarchy Process (AHP). The model established quantitative relationships among WEF sectors, simplifying the intricate interlinkages among resources, using South Africa as a case study. A spider graph was used to illustrate sector performance as related to others, whose management is viewed either as sustainable or unsustainable. The model was then applied to assess progress towards the Sustainable Development Goals in South Africa. The estimated integrated indices of 0.155 and 0.203 for 2015 and 2018, respectively, classify South Africa’s management of resources as marginally sustainable. The model is a decision support tool that highlights priority areas for intervention.
显示更多 [+] 显示较少 [-]An integrative analytical model for the water-energy-food nexus: South Africa case study
2020
Nhamo, L. | Mabhaudhi, T. | Mpandeli, S. | Dickens, Chris | Nhemachena, C. | Senzanje, A. | Naidoo, D. | Liphadzi, S. | Modi, A. T.
Synergetic optimization management of crop-biomass coproduction with food-energy-water nexus under uncertainties 全文
2020
Ji, Ling | Zheng, Zixuan | Wu, Tianhao | Xie, Yulei | Liu, Zhengping | Huang, Guohe | Niu, Dongxiao
Synergic management of the local crop-biomass coproduction system is the potential to increase resource efficiency and promote sustainable development. In this paper, an interval fuzzy linear fractional programming (IFLFP) model is developed for planning regional food production with the consideration of ecological protection, water resource conservation, biomass energy supply, and food-energy-water (FEW) nexus. The main advantages of the proposed IFLFP model are the abilities to reflect uncertainties with different characters as interval values and fuzzy sets and to provide system efficiency measurement by the ratio form of conflict objective functions. The IFLFP model is then tailored for the application of the crop-biomass coproduction management with FEW nexus in Jiangsu Province, China. The influences of different optimization goals (i.e. economic benefits and environmental benefits per unit irrigation water consumption) and multiple water resource scenarios under climate change are examined and discussed to provide more managerial insights. The results reveal that wheat, barley, and tuber crops would be more easily affected by water resource availability and optimization goals. Besides, recycle water would be considered as an important source for irrigation under scare water scenario, and gain the priority for the economic purpose. The results also imply that it is impossible to realize “double-win” of environmental and economic goals simultaneously, and decision makers should make compromises among different strategies.
显示更多 [+] 显示较少 [-]Ingestão de água em bovinos Brangus : relação entre equações de predição, comportamento alimentar e temperamento | Water intake in brangus cattle : relation to prediction equations, feeding behavior and temperament 全文
2020
Machado, Angélica Tarouco | Fischer, Vivian
Realizaram-se dois estudos, e primeiro deles objetivou verificar a influência do comportamento próximo ao comedouro e bebedouro sobre o consumo de água (CA) e avaliar a adequação das equações de predição para estimar o CA em bovinos Brangus no subtrópico. Os dados foram coletados em dois experimentos realizados no Rio Grande do Sul, na EEA-UFRGS, o primeiro em 2017, com 60 novilhas da raça Brangus e o segundo em 2018 com 30 bezerros da mesma raça. Os valores preditos foram calculados utilizando 6 equações previamente publicadas na literatura científica e comparados com os valores de CA medidos nos bebedouros automáticos. As análises de regressão linear entre CA medido e os valores preditos mostraram que todas as equações superestimaram o CA medido, devido a diferenças ambientais e genotípicas e fatores não considerados nas equações. Com as informações geradas nos experimentos, foram propostas equações de predição: CA= - 2,44 + (0,009 x PC) + (0,84 x CMS) – (0,10 x UR) + (0,64 x TMAX) e CA= - 2,52 + (0,96 x CMS) – (0,09 x UR) + (0,45 x TMAX) + (0,76 x NVCB) + (0,18 x TCB) - (0,02 x NVCC) + (1,81 x TI) para novilhas; e CA1= - 4,23 + (0,98 x CMS) + (0,50 x TMAX) - (0,98 x PP) e CA2 = 13,07 + (0,61 x CMS) - (0,14 x UR) + (0,34 x TMAX) – (0,91 x VV) - (0,09 x RS) + (0,99 x NVCB) para bezerros. As equações propostas para os bezerros foram validadas com dados coletados em outro período, com novilhos Brangus. Entre os dois modelos propostos no estudo, o modelo comportamental (CA2) apresentou maior coeficiente de determinação, com média estimada de CA de 9,49 kg para um CA medido de 19,55 kg/d. O segundo estudo objetivou avaliar a influência do temperamento sobre o consumo de água e alimentos de bezerros de corte confinados e analisar o efeito do temperamento sobre as características produtivas dos animais. Os dados foram coletados de 30 bezerros da raça Brangus no ano de 2018 em três avaliações. O temperamento foi avaliado como o escore composto de balança (escores de 1 a 5, de calmos a muito reativos) e, posteriormente, os animais foram categorizados em calmos, intermediários e reativos. O temperamento não influenciou o consumo de água e alimentar dos animais. Animais calmos ganharam menos peso no primeiro período de avaliação que os demais. Animais calmos permaneceram menos tempo no cocho que os demais. O presente estudo confirmou o baixo coeficiente de determinação dos modelos de predição de consumo de água e a superestimação do consumo. O consumo de água e alimentos e a maior parte dos atributos comportamentais ligados à ingestão não foram influenciado pelo temperamento dos bovinos. | Two studies were carried out, the first one aimed to verify the influence of the behavior close to the feeder and drinker on water intake (WI) and to evaluate the adequacy of the prediction equations to estimate the WI in Brangus cattle in the subtropical region. Data were collected in two experiments carried out in Rio Grande do Sul, at EEA- UFRGS. The first was in 2017 studying 60 Brangus heifers and the second was in 2018 studying 30 calves of the same breed. The predicted values were calculated using six previously published equations and compared with the WI values measured in the automatic drinkers. Linear regression analyzes between WI and predicted values demonstrated that all equations overestimated WI, due to both environmental and genotypic differences as well as to factors not considered in the equations. From the information generated in the experiments, new prediction equations were proposed: WI = - 2,44 + (0,009 x BW) + (0,84 x DMI) – (0,10 x HU) + (0,64 x MT) e WI = - 2,52 + (0,96 x DMI) – (0,09 x HU) + (0,45 x MT) + (0,76 x NVCB) + (0,18 x TCB) - (0,02 x NVCC) + (1,81 x TI) for heifers; and WI1 = - 4,23 + (0,98 x DMI) + (0,50 x MT) - (0,98 x PP) e WI2 = 13,07 + (0,61 x DMI) - (0,14 x HU) + (0,34 x MT) – (0,91 x WS) - (0,09 x SR) + (0,99 x NVCB) for calves. The proposed equations for the calves were validated with data collected in other period with Brangus steers. Among the two models proposed in the study, the behavioral model (WI2) presented the highest coefficient of determination, with an estimated mean of 9.49 kg of WI for an observed overall WI of 19.55 kg/d. The second article aimed to evaluate the influence of temperament on the consumption of water and feed of beef calves and to analyze the effect of temperament on the productive characteristics of animals. Data were collected from 30 Brangus calves in 2018 in three evaluations. The temperament was evaluated as the balance composed score (scores from 1 to 5 from calm to very reactive) and, later, the animals were categorized into calm, intermediate and reactive. The temperament did not influence the water and food consumption of the animals. Calm animals gained less weight in the first evaluation period than the rest of them. Calm animals spent less time in the feeder than the others. The present study confirmed the low coefficient of determination of the water intake prediction models and the overestimation of water consumption. The intake of water and food and most of the behavioral attributes linked to ingestion were not influenced by temperament in beef cattle raised in the subtropics.
显示更多 [+] 显示较少 [-]A systematic analysis of Water-Energy-Food security nexus: A South Asian case study 全文
2020
Putra, Muhammad Panji Islam Fajar | Pradhan, Prajal | Kropp, Jürgen P.
Most South Asian countries have challenges in ensuring water, energy, and food (WEF) security, which are often interacting positively or negatively. To address these challenges, the nexus approach provides a framework to identify the interactions of the WEF sectors as an integrated system. However, most nexus studies only qualitatively discuss the interactions between these sectors. This study conducts a systematic analysis of the WEF security nexus in South Asia by using open data sources at the country scale. We analyze interactions between the WEF sectors statistically, defining positive and negative correlations between the WEF security indicators as synergies and trade-offs, respectively. By creating networks of the synergies and trade-offs, we further identify most positively and negatively influencing indicators in the WEF security nexus. We observe a larger share of trade-offs than synergies within the water and energy sectors and a larger share of synergies than trade-offs among the WEF sectors for South Asia. However, these observations vary across the South Asian countries. Our analysis highlights that strategies on promoting sustainable energy and discouraging fossil fuel use could have overall positive effects on the WEF security nexus in the countries. This study provides evidence for considering the WEF security nexus as an integrated system rather than just a combination of three different sectors or securities.
显示更多 [+] 显示较少 [-]Electrospinning of zein-ethyl cellulose hybrid nanofibers with improved water resistance for food preservation 全文
2020
Niu, Ben | Zhan, Li | Shao, Ping | Xiang, Ning | Sun, Peilong | Chen, Hangjun | Gao, Haiyan
Zein electrospun nanofibers have poor water resistance, which restricts its applications in food preservation. To improve the water resistance of nanofibers, zein/ethyl cellulose (EC) hybrid nanofibers were prepared at different ratios. Besides, we also encapsulated cinnamon essential oil (CEO) into electrospun fibers for Agaricus bisporus preservation. As the weight ratio of EC increased from 0% (ZE-10) to 100% (ZE-01), the viscosity of electrospinning solutions gradually increased from 80.33 ± 19.23 mPa·s to 756.78 ± 22.48 mPa·s, resulting in sufficient chain entanglement for the preparation of uniform fibers. The average diameters of ZE-01, ZE-12, ZE-11, ZE-21, and ZE-10 nanofibers were 326 ± 53 nm, 267 ± 31 nm, 237 ± 51 nm, 292 ± 45 nm, and 362 ± 70 nm, respectively. The hydrogen bonds between the hydroxyl groups of ethyl cellulose and the amino groups of zein decreased the amount of free hydrophilic group, thus improving water resistance of nanofibers. Food packaging potential was evaluated using Agaricus bisporus. The zein/EC nanofibers loaded CEO significantly decreased weight loss and maintained the firmness of the Agaricus bisporus, and improved the quality of the Agaricus bisporus during storage.
显示更多 [+] 显示较少 [-]Polyphenols from waste streams of food industry: valorisation of blanch water from marzipan production 全文
2020
Hellwig, Veronika | Gasser, Johanna
Waste fractions of food processing are promising sources of polyphenols, which are of high demand because of their favourable bioactivities. More recently, also wastewater and process water fractions are in focus of research and technologies for downstream processing, which is reviewed here. Adsorption as well as membrane technologies are widely used to achieve selective recovery of polyphenols from waste water. For technical implementation the processing of waste fractions must be separated from the primary food production process. Therefore, the key step is the efficient transfer of the waste fractions into a storable and transportable form of polyphenol-enriched fractions. This strategy is shown exemplarily for the marzipan production. Almond skin and blanch water are waste fractions containing catechin and procyanidins, for which a recycling concept has been developed. The polyphenolic ingredients of the blanch water can be specifically adsorbed by means of Amberlite resins or zeolites with high yield followed by ultrafiltration.
显示更多 [+] 显示较少 [-]Supercritical water gasification of biomass and agro-food residues: Energy assessment from modelling approach 全文
2020
Macrì, Domenico | Catizzone, Enrico | Molino, Antonio | Migliori, Massimo
The gasification of biomass in supercritical water is a promising technology for hydrogen production and the paper reports a thermodynamic analysis, based on minimization of Gibbs free energy, of the gasification with supercritical water of different biomass and agro-food residues: almond shells, digestate from wastewater treatment, algae and manure sludge. Numerical simulations were performed in order to assess the effect of temperature, pressure and biomass-to-water ratio on gas-phase yield and composition.A partial energy integration was also discussed, by considering the energy recovery from a turbine expansion of the gas-phase stream leaving the gasifier. The proposed thermodynamic approach allows predicting not only gasification efficiency of gasifier but also energy balance on the entire gasification process. Results showed that the dry substrates (almond shells and algae more than digestate and sludge) tend to form more carbon monoxide. Besides, data comparison revealed that the produced hydrogen comes from biomass and water for high process temperature, while when temperature decreases, the thermodynamic path tends to promote water formation from the hydrogen of the dry biomass.
显示更多 [+] 显示较少 [-]Enteric viruses in surface water in Vojvodina as a risk for healthy food production 全文
2020
Lazić, Gospava (https://orcid.org/0000-0003-0537-7619) | Samojlović, Milena (https://orcid.org/0000-0002-5685-4027) | Lupulović, Diana (https://orcid.org/0000-0002-2476-4887) | Petrović, Tamaš (https://orcid.org/0000-0002-9164-3356) | Lazić, Sava
The quality of water used for drinking, irrigation, industrial food processing or for recreational purposes, has a very important impact on human and animal health. So far, 33 surface water localities have been examined in territory of Vojvodina for the presence of 7 different viruses. The prevalence of enteric viruses in the total number of examined localities was up to 60%. These results unequivocally confirm that there is a risk to the health of animals and humans in the area that gravitates to the examined surface water. The risk to public and animal health is particularly significant in areas and localities where the tested surface water are used for agricultural purposes.
显示更多 [+] 显示较少 [-]Integrated policies to improve the energy–water–food system nexus to achieve the SGDs 全文
2020
Bollino, Carlo Andrea; Anbumozhi, Venkatachalam; Babu, Suresh Chandra; Eiji, Yamaji; Galeotti, Marzio | http://orcid.org/0000-0002-8706-2516 Babu, S.
The challenges posed by the water–food–energy nexus have been well documented. Demand for all three of these crucial elements of human growth is increasing, driven by a rising global population, rapid urbanization, changing diets, and economic growth. However, an integrated approach to technological, institutional, and policy innovation is missing in the context of achieving the Sustainable Development Goals (SDGs). The proposed strategy in this policy brief relies on three pillars: (1) improvements in the measurement and promotion of better policies and investments for integrated energy, water, and food security; (2) the assessment of the institutional constraints and determinants of the inequalities between leading and lagging countries and the speed of adjustment that will bring convergence among them; and (3) the facilitation of renewable energy technologies as an environmentally sustainable supply of energy, with substantial positive spill-over effects in the water and food sectors. The suggestion is to promote policies to (1) facilitate which determinants are best suited to enhance the convergence of policy process, such as economic diversification, subsidy removal, and liberalization through a multisectoral approach; and (2) support increasing electricity access using alternative sources of energies in remote rural areas in Asia, Africa, and Latin America through integrated Official Development Assistance (ODA) and Foreign Direct Investment (FDI). | Non-PR | IFPRI5 | DSGD
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