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Future increases in irrigation water requirement challenge the water-food nexus in the northeast farming region of China النص الكامل
2019
Xu, Hanqing | Tian, Zhan | He, Xiaogang | Wang, Jun | Sun, Laixiang | Fischer, Günther | Fan, Dongli | Zhong, Honglin | Wu, Wei | Pope, Edward | Kent, Chris | Liu, Junguo
Northeast Farming Region of China (NFR) produces about one-third of the national maize output. Shortage of crop irrigation water is one of the main threat to the stable level of maize production in the NFR. Previous studies on the sensitivity of maize production to drought are typically based on field experiments and treat the maize growing season as a whole, with rare attention to the varying impacts of drought across different maize growth stages. Given the importance of NFR on China’s food security, it is crucial to optimize the irrigation schedule to mitigate the adverse effects of drought. In this study, we employ Agro-ecological Zone (AEZ) model to investigate how climate change affects irrigation water requirement (IWR) of maize during different growth stages and under different climate change scenarios. Results indicate that the NFR would experience a substantial increase in the probability of extremely shortage of crop irrigation water under future climate change. The ensemble simulation under future climate projections indicates more frequent demands for irrigation with substantially increased amount in the mid-season stage (G3) when maize is more sensitive to water deficit compared with other stages. These findings indicate that earlier planning of irrigation infrastructure and development of more efficient irrigation scheme and technologies is of great importance to secure maize production in the region.
اظهر المزيد [+] اقل [-]The food-water quality nexus in periurban aquacultures downstream of Bangkok, Thailand النص الكامل
2019
Mrozik, Wojciech | Vinitnantharat, Soydoa | Thongsamer, Thunchanok | Pansuk, Nipapun | Pattanachan, Pavinee | Thayanukul, Parinda | Acharya, Kishor | Baluja, Marcos Quintela | Hazlerigg, Charles | Robson, Aidan F. | Davenport, Russell J. | Werner, David
Peri-urban aquacultures produce nutritious food in proximity to markets, but poor surface water quality in rapidly expanding megacities threatens their success in emerging economies. Our study compared, for a wide range of parameters, water quality downstream of Bangkok with aquaculture regulations and standards. For parameters not meeting those requirements, we sought to establish whether aquaculture practice or external factors were responsible. We applied conventional and advanced methods, including micropollutant analysis, genetic markers, and 16S rRNA amplicon sequencing, to investigate three family-owned aquacultures spanning extensive, semi-intensive and intensive practices. Canals draining the city of Bangkok did not meet quality standards for water to be used in aquaculture, and were sources for faecal coliforms, Bacteriodes, Prevotella, Human E. coli, tetracycline resistance genes, and nitrogen into the aquaculture ponds. Because of these inputs, aquacultures suffered algae blooms, with and without fertilizer and feed addition to the ponds. The aquacultures were sources of salinity and the herbicide diuron into the canals. Diuron was detectable in shrimp, but not at a level of concern to human health. Given the extent and nature of pollution, peri-urban water policy should prioritize charging for urban wastewater treatment over water fees for small-scale agricultural users. The extensive aquaculture attenuated per year an estimated twenty population equivalents of nitrogen pollution and trillions of faecal coliform bacteria inputs from the canal. Extensive aquacultures could thus contribute to peri-urban blue-green infrastructures providing ecosystem services to the urban population such as flood risk management, food production and water pollution attenuation.
اظهر المزيد [+] اقل [-]High internal phase water-in-oil emulsions stabilized by food-grade starch النص الكامل
2019
Zhao, Qiang | Jiang, Lingxiang | Lian, Zhen | Khoshdel, Ezat | Schumm, Stephan | Huang, Jianbin | Zhang, Qiqing
Water in oil emulsions would be prepared by silicones (SO), modified silicones (DC8500) and a food-grade stabilizer (starch 1). With increasing water contents, the emulsions turned from a liquid-like to gel-like behaviors with enhancing storage and loss modulus. When DC8500/SO was 1/17 with 10 wt% starch 1, a high internal phase emulsion can be obtained with 95 wt% water content. DC8500 and SO worked as efficient emulsifiers and possessed amphiphilic property to form emulsions with water in different ratios. A food-grade starch 1 was supplied as a stabilizer which can enhance both water content and strength of emulsion when added in a low concentration. Besides, it is indicated that the food-grade starches provided potential benefit on stabilizing emulsions in very low concentration.
اظهر المزيد [+] اقل [-]Virtual water flow in food trade systems of two West African cities النص الكامل
2019
Akoto-Danso, Edmund K. | Karg, H. | Drechsel, Pay | Nyarko, G. | Buerkert, Andreas
Rapid urban growth in sub-Saharan Africa challenges food supply of cities. As food and other organic matter are transported from production areas to consumption points, water, which has been used for their production, is transported virtually. This study aimed at determining the magnitude and sources of virtual water flows in food trade of two West African cities, in order to better assess food provisioning risks and water resource use and planning. To this end, flows of unprocessed food from local, regional, national and international sources were systematically recorded at all roads leading to Tamale, Ghana and Ouagadougou, Burkina Faso. The survey was conducted within two years covering the peak (November - December) and lean season (March - April), respectively, for six days in a row. Virtual water flows were computed by multiplying the flow quantities (t yr-1) by their respective virtual water contents (m3 t-1). Results showed that virtual water of all food commodities imported to Tamale and Ouagadougou were 514 and 2105 million m3 yr-1 respectively, out of which 68% and 40% were re-exported to other regions of the country. The data also showed major seasonal variation in virtual water flows across the year. Reflecting their dominating role in local diets, cereals contributed most to the total virtual water inflows in both cities. Southern Ghana is the major net virtual water importer from Tamale through cereals, legumes, vegetables, and livestock. The Northern Region of Ghana, on the other hand, is a net exporter of virtual water in all food groups apart from fruits. In Ouagadougou, large flows of virtual water were imported in cereals, specifically rice from Asian countries, via Ivory Coast.
اظهر المزيد [+] اقل [-]The global nexus of food–trade–water sustaining environmental flows by 2050 النص الكامل
2019
Pastor, Amandine | Palazzo, A. | Havlik, P. | Biemans, H. | Wada, Y. | Obersteiner, M. | Kabat, P. | Ludwig, F.
The vulnerabilities of agricultural land and food production to future water scarcity
2019
Fitton, N. | Alexander, P. | Arnell, N. | Bajzelj, B. | Calvin, K. | Doelman, J. | Gerber, J.S. | Havlik, P. | Hasegawa, T. | Herrero, M. | Krisztin, T. | Meijl, van, H. | Powell, T. | Sands, R. | Stehfest, E. | West, P.C. | Smith, P.
Rapidly increasing populations coupled with increased food demand requires either an expansion of agricultural land or sufficient production gains from current resources. However, in a changing world, reduced water availability might undermine improvements in crop and grass productivity and may disproportionately affect different parts of the world. Using multi-model studies, the potential trends, risks and uncertainties to land use and land availability that may arise from reductions in water availability are examined here. In addition, the impacts of different policy interventions on pressures from emerging risks are examined. Results indicate that globally, approximately 11% and 10% of current crop- and grass-lands could be vulnerable to reduction in water availability and may lose some productive capacity, with Africa and the Middle East, China, Europe and Asia particularly at risk. While uncertainties remain, reduction in agricultural land area associated with dietary changes (reduction of food waste and decreased meat consumption) offers the greatest buffer against land loss and food insecurity.
اظهر المزيد [+] اقل [-]Nexus assessment for Sudan: Synergies of the water, energy and food sectors النص الكامل
2019
Babiker, Babiker | Salih, Ali | Siddig, Khalid | Ringler, Claudia
This report presents the main findings of the Nexus assessment study for Sudan. It identified Water-Energy-Food Nexus priority issues in Sudan, suggested operational guidance to align national strategies, policies and implementation plans within a national Nexus framework, identified opportunities to apply the Nexus approach, including institutional settings and capacity building needs, and suggested a series of Water-Energy-Food Nexus projects in Sudan.
اظهر المزيد [+] اقل [-]The vulnerabilities of agricultural land and food production to future water scarcity النص الكامل
2019
Fitton, N. | Alexander, P. | Arnell, N. | Bajzelj, B. | Calvin, K. | Doelman, J. | Gerber, J.S. | Havlik, P. | Hasegawa, T. | Herrero, M. | Krisztin, T. | van Meijl, H. | Powell, T. | Sands, R. | Stehfest, E. | West, P.C. | Smith, P.
Rapidly increasing populations coupled with increased food demand requires either an expansion of agricultural land or sufficient production gains from current resources. However, in a changing world, reduced water availability might undermine improvements in crop and grass productivity and may disproportionately affect different parts of the world. Using multi-model studies, the potential trends, risks and uncertainties to land use and land availability that may arise from reductions in water availability are examined here. In addition, the impacts of different policy interventions on pressures from emerging risks are examined.Results indicate that globally, approximately 11% and 10% of current crop- and grass-lands could be vulnerable to reduction in water availability and may lose some productive capacity, with Africa and the Middle East, China, Europe and Asia particularly at risk. While uncertainties remain, reduction in agricultural land area associated with dietary changes (reduction of food waste and decreased meat consumption) offers the greatest buffer against land loss and food insecurity.
اظهر المزيد [+] اقل [-]Virtual water flow in food trade systems of two West African cities النص الكامل
2019
Akoto-Danso, Edmund K. | Karg, H. | Drechsel, Pay | Nyarko, G. | Buerkert, Andreas
Rapid urban growth in sub-Saharan Africa challenges food supply of cities. As food and other organic matter are transported from production areas to consumption points, water, which has been used for their production, is transported virtually. This study aimed at determining the magnitude and sources of virtual water flows in food trade of two West African cities, in order to better assess food provisioning risks and water resource use and planning. To this end, flows of unprocessed food from local, regional, national and international sources were systematically recorded at all roads leading to Tamale, Ghana and Ouagadougou, Burkina Faso. The survey was conducted within two years covering the peak (November - December) and lean season (March - April), respectively, for six days in a row. Virtual water flows were computed by multiplying the flow quantities (t yr-1) by their respective virtual water contents (m3 t-1). Results showed that virtual water of all food commodities imported to Tamale and Ouagadougou were 514 and 2105 million m3 yr-1 respectively, out of which 68% and 40% were re-exported to other regions of the country. The data also showed major seasonal variation in virtual water flows across the year. Reflecting their dominating role in local diets, cereals contributed most to the total virtual water inflows in both cities. Southern Ghana is the major net virtual water importer from Tamale through cereals, legumes, vegetables, and livestock. The Northern Region of Ghana, on the other hand, is a net exporter of virtual water in all food groups apart from fruits. In Ouagadougou, large flows of virtual water were imported in cereals, specifically rice from Asian countries, via Ivory Coast.
اظهر المزيد [+] اقل [-]Water-energy-food nexus: A case study on medicinal and aromatic plants النص الكامل
2019
Litskas, Vassilis | Chrysargyris, Antonios | Stavrinides, Menelaos | Tzortzakis, Nikolaos
Medicinal and Aromatic Plants (MAPs) are broadly cultivated in the Mediterranean but their environmental footprint is not very well studied. In this paper, Life Cycle Assessment (LCA) was applied to determine the energy balance, carbon and water footprints (CF and WF, respectively) in 50 farms, organic and conventional, where four MAP species were cultivated; spearmint (Mentha spicata), oregano (Oreganum vulgare), rosemary (Rosmarinus officinalis) and Damask rose (Rosa damascena). The lowest value for energy intensity (EI) was observed for organic spearmint (0.18 MJ/kg fresh weight; f.w.) while the highest for conventional Damask rose (5.80 MJ/kg f.w.). Statistically significant differences were observed in EI between organic and conventional farms for spearmint and Damask rose while no differences were found for oregano and rosemary. The lowest CF was observed for organic rosemary (0.051 kg CO₂-eq/kg f.w.) while the highest for conventional Damask rose (0.463 kg CO₂-eq/kg f.w.). Statistical differences in the CF between organic and conventional farms for the four species followed the same pattern as for EI. Conventional spearmint had the lowest WF (61.5 L of water/kg f.w.) and organic Damask rose the highest (1522 L of water/kg f.w.). Statistical differences between the two management systems were observed only for Damask rose. The 50 farms were grouped according to the values of three indicators (EI, CF and WF) using cluster analysis. Four clusters were identified with 68% of the farms (34) belonging to the low footprint cluster which contained organic and conventional spearmint, oregano and rosemary farms. The other three clusters contained the (16) Damask rose farms, where the inputs were higher in comparison to the other three species and the highest footprint clusters contained conventional rose farms. Our work suggests that MAPs are viable candidates for the implementation of sustainable agriculture in the Mediterranean.
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