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Future water availability for global food production: The potential of green water for increasing resilience to global change 全文
2009
Rockström, Johan | Karlberg, Louise | Hoff, Holger | Rost, Stefanie | Gerten, Dieter
While past strategies for agricultural water management have focused on irrigation (use of blue water), this paper demonstrates the dominance of green water in food production. A global, yet spatially disaggregated, green-blue analysis of water availability and requirement, using the LPJmL dynamic vegetation and water balance model, indicates that many countries currently assessed as severely water short are able to produce enough food for their populations if green water is considered and is managed well. The need to integrate green and blue water management is highlighted in a future scenario of water availability under climate change and population growth (HadCM2 A2). For 2050, the scenario indicates that 59% of the world population will face blue water shortage, and 36% will face green and blue water shortage. Even under climate change, good options to build water resilience exist without further expansion of cropland, particularly through management of local green water resources that reduces risks for dry spells and agricultural droughts.
显示更多 [+] 显示较少 [-]Natural food evaluation and water quality in zero water exchange culture of Litopenaeus vannamei fertilized with wheat bran 全文
2009
Campos, Susmara Silva | Silva, Ugo Lima | Lúcio, Maria Zita Tabosa | Correia, Eudes de Souza
The aim of this study was to analyze the influence of organic fertilizer on the availability of natural food (plankton and benthos) and water quality. Two fertilization protocols were adopted using inorganic and organic fertilizers with shrimp (stocked treatment) and their controls (unstocked treatment). Experimental units consisted of 12 circular fiberglass tanks (500 l) with estuarine sediment, individual aeration and no water exchange. In stocked treatments were used 40 juveniles/m², and they were fed with 35% crude protein marine shrimp ration, three times a day. Under the organic fertilization protocol, the plankton showed higher abundance of Nitzschia and rotifers, the phytobenthos consisted mainly of Nitzschia, Amphiprora and Oscillatoria, the epibenthos was represented mainly by nematodes and rotifers, and the macro-invertebrates were mainly oligochaetes. In relation to inorganic fertilization, the plankton was represented mainly by Coscinodiscus and rotifers, the phytobenthos consisted mainly of Amphiprora and Oscillatoria, the epibenthos was represented mainly by nematodes and rotifers, and the macro-invertebrates were mainly oligochaetes. Dissolved oxygen was higher for organic fertilizer (6.16 ± 0.98 mg/l) than for inorganic (5.92 ± 1.19 mg/l) while the other water quality parameters did not present significant differences. Survival was similar in the two fertilization regimes (96.6%). Final body weight was 11.89 ± 1.73 g for the inorganic fertilizers and 12.28 ± 1.71 g for organic fertilizer. It is concluded that wheat bran showed good performance in the water quality without exchange, in the availability of natural food, and in the growth and survival of the shrimps in the microcosms.
显示更多 [+] 显示较少 [-]Water management and crop production for food security in China: A review 全文
2009
K̲h̲ān, Shahbāz | Hanjra, Munir A. | Mu, Jianxin
Food security is a high priority issue on the Chinese political agenda. China's food security is challenged by several anthropogenic, sociopolitical and policy factors, including: population growth; urbanization and industrialization; land use changes and water scarcity; income growth and nutritional transition; and turbulence in global energy and food markets. Sustained growth in agricultural productivity and stable relations with global food suppliers are the twin anchors of food security. Shortfalls in domestic food production can take their toll on international food markets. Turbulence in global energy markets can affect food prices and supply costs, affecting food security and poverty. Policy safeguards are needed to shield food supply against such forces. China must make unremitting policy responses to address the loss of its fertile land for true progress towards the goal of national food security, by investing in infrastructure such as irrigation, drainage, storage, transport, and agricultural research and institutional reforms such as tenure security and land market liberalization. The links between water and other development-related sectors such as population, energy, food, and environment, and the interactions among them require reckoning, as they together will determine future food security and poverty reduction in China. Climate change is creating a new level of uncertainty in water governance, requiring accelerated research to avoid water-related stresses.
显示更多 [+] 显示较少 [-]Nutrient removal from polluted stream water by artificial aquatic food web system 全文
2009
Jung, Dawoon | Cho, Ahnna | Zo, Young-Gun | Choi, Seung-Ik | An, Tʻae-sŏk
For the removal of nutrients from eutrophic stream water polluted by non-point sources, an artificial aquatic food web (AAFW) system comprising processes of phytoplankton growth and Daphnia magna grazing was developed. The AAFW system was a continuous-flow system constructed with one storage basin of 3 m³ capacity, one phytoplankton tank of 3 m³ capacity, and one zooplankton growth chamber of 1.5 m³ capacity. The system was optimized by setting hydraulic retention time of phytoplankton tank as 3 days and D. magna density as 740-1000 individual l⁻¹. When the system was operated on eutrophic stream water that was delivering 471 g of total nitrogen (TN) and 29 g of total phosphorus (TP) loadings for 45 days, 250 g (53%) of TN and 16 g (54%) of TP were removed from the water during its passage through the phytoplankton tank. In addition, 64 g (14%) of TN and 4 g (13%) of TP were removed from the water by harvesting zooplankton biomass in the zooplankton growth chamber, resulting in significant overall removal rates of TN (69%), nitrate (78%), TP (73%), and dissolved inorganic phosphorus (94%). While the removal efficiency of the AAFW system is comparable to those of other ecotechnologies such as constructed wetlands, its operation is less limited by the availability of space or seasonal shift of temperature. Therefore, it was concluded that AAFW system is a highly efficient, flexible system for reducing nutrient levels in tributary streams and hence nutrient loading to large aquatic systems receiving the stream water.
显示更多 [+] 显示较少 [-]CGIAR Challenge Program on Water and Food - Medium Term Plan 2010-2012 全文
2009
The revised objective of the CPWF is: “To increase the productivity of water for food and livelihoods, in a manner that is environmentally sustainable, socially acceptable, and alleviates poverty for disadvantaged groups”.<br/><br/>This document outlines the medium-term plan of the CPWF. Plans are presented for the six river basins focused on during Phase II: the Ganges, Mekong, Nile, Limpopo, Volta and Andes. Cross-basin learning is discussed in a final section of the Plan.
显示更多 [+] 显示较少 [-]Regulatory issues regarding the use of food and water restriction in laboratory animals 全文
2009
Willems, Robert A.
While investigating certain aspects of animal physiology, neurology or behavior, research scientists sometimes must limit the amount of food or water provided to animals used in a study. Such limitations can negatively impact the health and welfare of laboratory animals by, for example, causing them to experience distress or pain. The author discusses the veterinary and regulatory concerns that laboratory personnel should consider when limiting food or water given to research animals. He concludes that by adequately addressing the needs of animals receiving less food or water than required by regulation, researchers will improve both animal care and scientific study results.
显示更多 [+] 显示较少 [-]Most Significant Change Stories from the Challenge Program on Water and Food (CPWF)
2009
León, C. de | Douthwaite, Boru | Álvarez, S.
The following stories were collected from CPWF project and theme leaders in two rounds. The first round of stories were collected in January 2007 based on the following two questions: What has been the most significant technical development or advance made by your 1) CPWF project / theme / basin since the start? What has been the most significant partnership change (significant in terms of making 2) scientific progress and/or developmental impact more likely) that has taken place since the start of your CPWF project (or theme or basin)? In June 2009 we repeated the process asking the same basic question, without specifying between technical and partnership changes. We asked for photographs and references to documents that substantiate the stories. We collected 54 stories in Round 1, and 15 in Round 2. A selection of 44 stories are presented here. Those we left out we did so if the stories they told were not clear, if they did not follow the format, or if we did not receive answers to clarifying questions. T he stories are organized by the CPWF’s five themes and according to First Call projects, Basin Focal Projects and Small Grants projects. They show the broad range of outcomes and impacts that the CPWF is beginning to have. The stories are not a comprehensive audit of CPWF impact, but rather what people felt motivated to write about. The stories provide gateways to evidence of change, and are not to be interpreted as definitive but as iterative. Indeed, some projects presented change stories in both rounds. CPWF Theme Leaders selected the first round story or stories they thought most significant and gave their reasons. The selection decisions and criteria are given as feedback to the projects as a way for the CPWF to focus innovation towards explicitly valued directions and away from less valued ones. One story was selected as the most significant from the second round stories. T he Most Significant Change (MSC) method was used to collect and analyze the stories1. MSC is part of a repertoire of iterative learning-based approaches that are employed by the CPWF and its projects in response to emergent change. The authors of the stories are principally the program’s Theme Leaders, Project Leaders and Principle Investigators. In writing the stories they were able to give their interpretation of the emerging issues and changes that most mattered to the leadership in these projects.
显示更多 [+] 显示较少 [-]Rapid Planar Chromatographic Analysis of 25 Water-Soluble Dyes Used as Food Additives
2009
Morlock, Gertrud E. | Oellig, Claudia
A rapid planar chromatographic method for identification and quantification of 25 water-soluble dyes in food was developed. In a horizontal developing chamber, the chromatographic separation on silica gel 60F(254) high-performance thin-layer chromatography plates took 12 min for 40 runs in parallel, using 8 mL ethyl acetate-methanol-water-acetic acid (65 + 23 + 11 + 1, v/v/v/v) mobile phase up to a migration distance of 50 mm. However, the total analysis time, inclusive of application and evaluation, took 60 min for 40 runs. Thus, the overall time/run can be calculated as 1.5 min with a solvent consumption of 200 μL. A sample throughput of 1000 runs/8 h day can be reached by switching between the working stations (application, development, and evaluation) in a 20 min interval, which triples the analysis throughput. Densitometry was performed by absorption measurement using the multiwavelength scan mode in the UV and visible ranges. Repeatabilities [relative standard deviation (RSD), 4 determinations] at the first or second calibration level showed precisions of mostly <or=2.7%, ranging between 0.2 and 5.2%. Correlation coefficient values (R >= 0.9987) and RSD values (<or=4.2%) of the calibration curves were highly satisfactory using classical quantification. However, digital evaluation of the plate image was also used for quantification, which resulted in RSD values of the calibration curves of mostly <or=3.0%, except for two <or=6.0%. The method was applied for the analysis of some energy drinks and bakery ink formulations, directly applied after dilution. By recording of absorbance spectra in the visible range, the identities of the dyes found in the samples were ascertained by comparison with the respective standard bands (correlation coefficients >or= 0.9996). If necessary for confirmation, online mass spectra were recorded within a minute.
显示更多 [+] 显示较少 [-]Most significant change stories from the Challenge Program on Water and Food (CPWF)
2009
León, C. de | Douthwaite, Boru | Álvarez, S.
Microbial quality of food snacks and drinking water in Islamabad schools and colleges
2009
Saddozai, A.A. (National Agricultural Research Centre, Islamabad (Pakistan). Grain Quality Testing Lab.) | Khalil, S. (National Agricultural Research Centre, Islamabad (Pakistan). Grain Quality Testing Lab.) | Hameed, T. (National Agricultural Research Centre, Islamabad (Pakistan). Grain Quality Testing Lab.)
The study was undertaken to determine the microbiological quality of various food items available in different schools and colleges of Islamabad. For sampling of water and food items, ten different schools and colleges were selected. These samples were analyzed for Total plate count (TPC), Total coliform, Fecal coliform, E. coli. Yeasts and Moulds. The data revealed that out of 30 water and 10 food samples, 12 samples of water and only 3 samples of food were found within range of permissible limits while the remaining were highly contaminated and unfit for human consumption. This study has socio-economic benefit monitoring the health standards of population especially the young generation.
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