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Reconciling food and water security objectives of MENA and sub-Saharan Africa: is there a role for large-scale agricultural investments? النص الكامل
2015
Williams, Timothy Olalekan
The attainment of food and water security rank high on the agendas of governments in the Middle East and North Africa (MENA) region and sub-Saharan Africa (SSA). Although the objectives are similar, the underlying drivers, resource endowments and opportunities for achieving them are different. Differences between two regions in natural resource endowment and investment capital stock can, in theory, lead to mutually beneficial trade to achieve desired objectives. Concerns about the recent food crises coupled with the disparity in land and water endowment and investable capital between MENA and SSA have led in recent years to investment in agricultural land in the latter by a number of MENA countries with the aim of producing food. At the same time, many SSA countries seek these investments to infuse capital, technology and know-how into their agricultural sector to improve productivity, food security and rural livelihoods. However, these recent foreign direct agricultural investments have to date performed poorly or have been abandoned without achieving the initial objectives of setting them up. Based on research conducted in selected sub-Saharan countries, this paper analyses the reasons for the failure of these investments. It then reviews a few successful agricultural investments by private sector companies with a long history of operation in SSA. Juxtaposing lessons distilled from failed and successful case studies, the paper argues that large-scale agricultural investments that take advantage of this accumulated knowledge are needed and do have a critical role to play. Such investments, when they also incorporate ecosystems management practices and smallholder inclusive business models in their operations, can serve as appropriate instruments to reconcile the food and water security objectives of both the MENA region and SSA, while promoting sustainable intensification of agriculture and improved rural livelihoods in SSA.
اظهر المزيد [+] اقل [-]The effect of water management on extensive aquaculture food webs in the reconstructed wetlands of the Doñana Natural Park, Southern Spain النص الكامل
2015
Walton, M.E.M. | Vilas, César | Coccia, Cristina | Green, Andy J. | Cañavate, J. Pedro | Prieto, A. | Berjeijk, S.A. van | Medialdea, J.M. | Kennedy, H. | King, J. | Le Vay, Lewis
© 2015 Elsevier B.V. Extensive aquaculture in coastal and estuarine wetlands can support both increased food production and wider ecosystem services when underpinned by effective management to promote productivity and hence food webs that support both commercial species and biodiversity. Changing hydrology, specifically water movement, within wetlands significantly impacts the physico-chemical properties of the water body and hence can be employed to manipulate productivity and alter patterns of recruitment of commercial species and may also transfer non-native species from the supplying water bodies. The reconstructed wetlands of Veta la Palma in the Doñana Natural Park are subjected to either a 1% or 5%d<sup>-1</sup> water exchange with water drawn from the adjacent Guadalquivir estuary. This site provides an excellent opportunity for examining the effect of water management on the food webs that support both the birdlife and aquaculture activities for which this habitat is managed. Stable isotopes were used to examine food webs in three replicate lagoons under each water management scheme. In lagoons receiving higher water exchange, phytoplankton productivity appeared to be more important than benthic production in supporting food webs. Increased water exchange also changed the shape of the food webs, facilitated the colonisation of at least one non-native species and increased the importance of non-native species in the diets of large commercially harvested fish (>60% of seabass diet). Lagoons with high water flows also had between three and four times greater shrimp biomass than those of low flow lagoons. Non-native fauna were opportunistic omnivores, eating marginally more non-natives in lagoons with greater water exchange. Overall non-native cordgrass Spartina densiflora contributed only slightly more to food webs compared with the native reed Phragmites australis, despite the lagoon edge occupancy ratio of 9:1, respectively. Non-natives also appear to enhance food provision for large predators and wetland birds, by increasing biomass, without competing for resources with native species, supporting the dual management objectives of aquaculture and waterbird conservation. Statement of relevance: Extensive aquaculture productivity appears to be positively correlated with water exchange rates. | Peer Reviewed
اظهر المزيد [+] اقل [-]Chinese State-Owned Enterprise Investment in Mekong Hydropower: Political and Economic Drivers and Their Implications across the Water, Energy, Food Nexus النص الكامل
2015
Nathanial Matthews | Stew Motta
Over the last decade, Chinese State-Owned Enterprises have emerged as among the most active investors in Mekong Basin hydropower development. This paper uses a political economy analysis to examine the forces that drive Chinese State-Owned Enterprises to invest in hydropower in the Mekong Basin. We focus our analysis on the Lancang (Upper Mekong River) in China and in the Greater Mekong Subregion (GMS), with an emphasis on Cambodia. The analysis reveals how powerful political and economic forces from within China and the GMS influence the pace, location and scale of investments in hydropower. These forces include foreign exchange reserves, trade packages and foreign direct investment, and political alliances. Combining the political economy and nexus approaches, we conclude that although policies from China recognize interconnections across the nexus, political and economic forces craft narratives that downplay or disregard these nexus interconnections and trade-offs. This in turn, influences how trade-offs and interconnections in hydropower development are managed and recognized in both local and transboundary contexts, thereby, creating potentially significant negative impacts on livelihoods, food security and the environment.
اظهر المزيد [+] اقل [-]The role of land and water for trade and food production in Latin America: Environmental trade-offs of agricultural intensification versus extensification النص الكامل
2015
Flaschsbarth, Insa | Willaarts, Barbara | Garrido Colmenero, Alberto | Xie, Hua | Pitois, Gauthier | Mueller, Nathaniel D. | Ringler, Claudia | Garrido Colmenero, Alberto
One of humanity’s major challenges of the 21st century will be meeting future food demands on an increasingly resource constrained-planet. Global food production will have to rise by 70 percent between 2000 and 2050 to meet effective demand which poses major challenges to food production systems. Doing so without compromising environmental integrity is an even greater challenge. This study looks at the interdependencies between land and water resources, agricultural production and environmental outcomes in Latin America and the Caribbean (LAC), an area of growing importance in international agricultural markets. Special emphasis is given to the role of LAC’s agriculture for (a) global food security and (b) environmental sustainability. We use the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT)—a global dynamic partial equilibrium model of the agricultural sector—to run different future production scenarios, and agricultural trade regimes out to 2050, and assess changes in related environmental indicators. Results indicate that further trade liberalization is crucial for improving food security globally, but that it would also lead to more environmental pressures in some regions across Latin America. Contrasting land expansion versus more intensified agriculture shows that productivity improvements are generally superior to agricultural land expansion, from an economic and environmental point of view. Finally, our analysis shows that there are trade-offs between environmental and food security goals for all agricultural development paths.
اظهر المزيد [+] اقل [-]Evaluation of ultrasound-assisted in situ sorbent formation solid-phase extraction method for determination of arsenic in water, food and biological samples النص الكامل
2015
Ezoddin, Maryam | Majidi, Behrooz | Abdi, Khosrou
A simple and rapid ultrasound-assisted in situ sorbent formation solid-phase extraction (UAISFSPE) coupled with electrothermal atomic absorption spectrometry detection (ET-AAS) was developed for preconcentration and determination of arsenic (As) in various samples. A small amount of cationic surfactant is dissolved in the aqueous sample containing As ions, which were complexed by ammonium pyrrolidinedithiocarbamate After shaking, a little volume of hexafluorophosphate (NaPF ₆) as an ion-pairing agent was added into the solution by a microsyringe. Due to the interaction between surfactant and ion-pairing agent, solid particles are formed. The alkyl groups of the surfactant in the solid particles strongly interact with the hydrophobic groups of analytes and become bound. Sonication aids the dispersion of the sorbent into the sample solution and mass transfer of the analyte into the sorbent, thus reducing the extraction time. The solid particles are centrifuged, and the sedimented particles can be dissolved in an appropriate solvent to recover the absorbed analyte. After separation, total arsenic (As(III) and As(V)) was determined by ET-AAS. Several experimental parameters were investigated and optimized. A detection limit of 7 ng L ⁻¹ with preconcentration factor of 100 and relative standard deviation for 10 replicate determinations of 0.1 µg L ⁻¹ As(III) were 4.5% achieved. Consequently, the method was applied to the determination of arsenic in certified reference materials, water, food and biological samples with satisfactory results.
اظهر المزيد [+] اقل [-]Treatment of a mixture of food color additives (E122, E124 and E129) in different water matrices by UVA and solar photoelectro-Fenton النص الكامل
2015
Thiam, Abdoulaye | Sirés, Ignasi | Brillas, Enric
The degradation of 130 mL of mixtures of food azo dyes E122, E124 and E129 has been studied by electro-Fenton (EF) and UVA photoelectro-Fenton (PEF) using a stirred tank reactor with either a boron-doped diamond (BDD) or Pt anode and an air-diffusion cathode. The main oxidant was hydroxyl radical formed at the anode from water oxidation and in the bulk from Fenton's reaction between added Fe2+ and H2O2 generated at the cathode. In sulfate medium, fast decolorization was found for all systems, but the almost total mineralization was more rapidly achieved by PEF with BDD. The performance with a real water matrix was slightly worse, although the removal of total organic load was still as high as 95%. The solar PEF (i.e., SPEF) treatment of dye mixtures using a 2.5 L flow plant with a BDD/air-diffusion cell coupled to a planar solar photoreactor is also reported. Fast decolorization and almost total mineralization was found in the presence of either sulfate, perchlorate, nitrate or a mixture of sulfate + chloride ions. In chloride medium, however, the formation of recalcitrant chloroderivatives decelerated the degradation process. Greater current efficiency and lower specific energy consumption were attained in sulfate medium at lower current density and higher azo dye content. A plausible reaction sequence based on 18 aromatic intermediates identified by GC–MS and 6 short-linear carboxylic acids detected by ion-exclusion HPLC has been proposed. The SPEF process promoted the photodegradation of Fe(III)-oxalate complexes and other undetected products. Sulfate and nitrate ions were always released to the medium.
اظهر المزيد [+] اقل [-]Study on extraction conditions of water-soluble substances: Purity test (4) for polyvinylpolypyrrolidone listed in Japan's specifications and standards for food additives النص الكامل
2015
Yanagi, T. (Japan Food Research Laboratories, Tama-shi, Tokyo (Japan). Tama Laboratory) | Matsumoto, M. | Shimizu, S. | Iwamura, T. | Ogaki, M.
The food additive polyvinylpolypyrrolidone is approved for use as a filter aid. The water-soluble substances test of polyvinylpolypyrrolidone often shows poor reproducibility. The instruction 'boil gently while stirring using a stirrer' was considered critical, and so this issue was examined. The results showed that the use of a combination of both an oil bath and a stirrer provided good reproducibility without decomposition or other problems.
اظهر المزيد [+] اقل [-]Programa de cooperación y articulación para la producción de alimentos soberanos: pequeños productores, tierra y agua recursos transformadores (PCAPASFACSO- UNICEN) النص الكامل
2015
Valerio, María del Carmen | Flores, Álvaro Dardo | Reitz, Maximiliano
Este Programa surge en el año 2012 en la cátedra de Antropología Rural, Facultad de Ciencias Sociales de la UNCPBA. Desprendida de sus experiencias por Latinoamérica y Europa, la Doctora Valerio ve la necesidad de organizar a los pequeños productores del periurbano olavarriense para que desarrollen sus actividades de producción revalorizando su capital cultural, compuesto por saberes productivos distintivos del ámbito rural y ubicando sus productos en una actividad de feria. Lo que les permitirá producir excedentes destinados al intercambio, trueque y venta. Los valores que guían al programa son de producción sustentable, cuidado de los recursos y desarrollo autónomo cooperativo. El proyecto se encuentra en la fase media de desarrollo, implicando esto el montaje y estructuración de las unidades productivas. El criterio para la selección se basó primero en la gran presencia de vecinos con producciones rurales en los patios y baldíos, y segundo, en que esta zona se encuentra postergada desde las políticas municipales. | Eje: B6 Desarrollo rural, movimientos sociales, Estado y agroecología (Relatos de experiencias) | Facultad de Ciencias Agrarias y Forestales
اظهر المزيد [+] اقل [-]Nexus meets crisis: a review of conflict, natural resources and the humanitarian response in Darfur with reference to the water–energy–food nexus النص الكامل
2015
Bromwich, Brendan
Darfur has been widely used as a case study by both those arguing for causality between environmental scarcity and war and those disputing it. This article challenges that approach by drawing on debates taking place within Darfur, reflecting on both the conflict and the humanitarian response. It argues that reviewing Darfur on its own terms makes a stronger basis to identify transferable lessons for interventions elsewhere. It considers water, food and energy, and finds that supporting governance is an essential theme for promoting economic recovery and laying a foundation for a well-managed water–energy–food nexus.
اظهر المزيد [+] اقل [-]Phosphorus budget in the water-agro-food system at nested scales in two contrasted regions of the world (ASEAN-8 and EU-27) النص الكامل
2015
Garnier, Josette | Lassaletta, Luis | Billen, Gilles | Romero, Estela | Grizzetti, Bruna | Nemery, Julien | Le, Thi Phuong Quynh | Pistocchi, Chiara | Aissa-Grouz, Najla | Luu, Thi Nguyet Minh | Vilmin, Lauriane | Dorioz, Jean Marcel | Université Pierre et Marie Curie - Paris 6 (UPMC) | Netherlands Environmental Assessment Agency | Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain] (CSIC) | JRC Institute for Environment and Sustainability (IES) ; European Commission - Joint Research Centre [Ispra] (JRC) | Centre National de la Recherche Scientifique (CNRS) | Université Joseph Fourier - Grenoble 1 (UJF) | Vietnam Academy of Science and Technology (VAST) | Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich) | Centre de Géosciences (GEOSCIENCES) ; Mines Paris - PSL (École nationale supérieure des mines de Paris) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL) | Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL) ; Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])
International audience | Phosphorus (P) plays a strategic role in agricultural production as well as in the occurrence of freshwater and marine eutrophication episodes throughout the world. Moreover, the scarcity and uneven distribution of minable P resources is raising concerns about the sustainability of long-term exploitation. In this paper we analyze the P cycle in anthropic systems with an original multiscale approach (world region, country, and large basin scales) in two contrasting world regions representative of different trajectories in socioeconomic development for the 1961-2009 period: Europe (EU-27)/France and the Seine River Basin, and Asia (ASEAN-8)/Vietnam and the Red River Basin. Our approach highlights different trends in the agricultural and food production systems of the two regions. Whereas crop production increased until the 1980s in Europe and France and has stabilized thereafter, in ASEAN-8 and Vietnam it began to increase in the 1980s and it is still rising today. These trends are related to the increasing use of fertilizers, although in European countries the amount of fertilizers sharply decreased after the 1980s. On average, the total P delivered from rivers to the sea is 3 times higher for ASEAN-8 (300kgPkm(-2)yr(-1)) than for EU-27 countries (100kgPkm(-2)yr(-1)) and is twice as high in the Red River (200kgPkm(-2)yr(-1)) than in the Seine River (110kgPkm(-2)yr(-1)), with agricultural losses to water in ASEAN-8 3 times higher than in EU-27. Based on the P flux budgets, this study discusses early warnings and management options according to the particularities of the two world regions, newly integrating the perspective of surface water quality with agricultural issues (fertilizers, crop production, and surplus), food/feed exchanges, and diet, defining the so-called water-agro-food system.
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