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Influences of low water temperature and food availability in winter on the survival and feeding of the rabbitfish, Siganus fuscescens in captivity
2018
Ueta, Y. (Tokushima Agriculture, Forestry, and Fisheries Technology Support Center, Kaifu, Tokushima (Japan). Fisheries Research Institute Minami Branch) | Tanada, N.
Rabbitfish, Siganus fuscescens 16.6 to 24.3cm in fork length caught off Tokushima Prefecture in the Pacific Ocean were used for these experiments. These fishes were reared by feeding fish only (experiment I) and both fish and seaweed (experiment II) under continuous flowing seawater conditions during November 2015 to February 2016 and the influence of low water temperature in winter on the survival and feeding was examined. The feeding on fishes stopped at 10.6-10.7 and on seaweed stopped at 12.9degC. Siganus fuscescens in experiment I started to die from 11.1degC (January 24) and one in experiment II from 10.4degC (February 11). These results show that low water temperature below 10.6-12.9degC led to exhaustion of Siganus fuscescens. The lower limiting water temperature for survival was estimated to be 10.4-11.1degC and feeding on both fish and seaweed enhanced the tolerance to low water temperature.
Afficher plus [+] Moins [-]Operationalizing the WEF nexus: quantifying the trade-offs and synergies between the water, energy and food sectors : Dutch Climate Solutions research programme
2018
Altamirano, M.A. | Bodegom, van, A.J. | Linden, van der, Nico | Rijke, de, Hugo | Verhagen, A. | Bucx, Tom | Boccalon, Agnese | Zwaan, van der, Bob
The purpose of this research is to develop an analytical and modelling approach that allows for the quantification of trade-offs between the water, energy and food nexus at different scales; allowing to go from national analysis of nexus stress by identifying and quantifying key intersectoral claims and trade-offs, up to a more detailed and even local specific analysis of the trade-offs. These trade-offs and the system understanding created by following the proposed steps for the analysis of nexus stress, inform them the design of Climate Smart Solutions and Strategies that make use of the most powerful leverage points and introduce or exploit existing synergies between the water-energy-food sectors. The national and local scales analyses following the proposed methodology have been applied to Ethiopia. At the national scale the integration has been done by making use of system analysis techniques in combination with the use of diverse modelling techniques for the quantification of the key trade-offs identified. The soft-linking Deltares Water Allocation Model (Ribasim) and TIAM-ECN model for optimization of Energy Systems allowed for the quantification of trade-offs between the water and the energy sectors given the national plans to make significant increase in hydropower dams. This modelling exercise was complemented with excel calculations to quantify the trade-off between biomass production for energy and land available for food production, as well as to quantify the complex linkages between water and food security.
Afficher plus [+] Moins [-]Effect of food preparation using naturally-contaminated groundwater from La Pampa, Argentina: Estimation of elemental dietary intake from rice and drinking water Texte intégral
2018
Jaafar, Maisarah | Marcilla, Andrea L. | Felipe-Sotelo, Mónica | Ward, Neil I.
Water from La Pampa, Argentina, was used for washing and cooking rice to examine the in-situ impact of using naturally-contaminated water for food preparation on the elemental dietary intake. Whilst washing with the control tap water (28 μg/L As) reduced the concentration of As in rice by 23%, the use of different well waters (281–1144 μg/L) increased As levels significantly (48–227%) in comparison with the original concentration in the rice (0.056 µg/g). Cooking the rice at a low water-to-rice ratio (2:1) using modern methods increased the levels of As in the cooked samples by 2–3 orders of magnitude for both pre-washed and un-washed rice. Similar trends were observed for vanadium. Although the levels of manganese, iron, copper, zinc and molybdenum in rice were reduced during washing and cooking for most water samples, the molybdenum concentration in the cooked rice doubled (2.2–2.9 µg/g) when using water containing >1 mg/L Mo.
Afficher plus [+] Moins [-]Food web structure and ecosystem properties of the largest impounded lake along the eastern route of China's South-to-North Water Diversion Project Texte intégral
2018
Guo, Chuanbo | Chen, Yushun | Li, Wei | Xie, Songguang | Lek, Sovan | Li, Zhongjie
Hongze Lake (HZL) is the largest impounded lake along the eastern route of China's South-to-North Water Diversion Project. However, there is surprisingly little ecological understanding on this important ecosystem, especially under the potential water diversion threats. Here, a mass-balance model was constructed to characterize trophic structure and ecosystem properties of HZL. The model outputs indicated that small sized fishes have dominated the food web, and fishery resources were suffered from high pressures of overfishing. Mandarin fish, Northern snakehead, Other piscivores and Large culters occupied the top trophic niche, while macrophytes, phytoplankton and detritus consisted of the main energy sources. HZL food web was fairly based on two main food chains: primary production (49.9%) and detritus pool (50.1%), but transfer efficiencies in both chains were relatively low as 6.37% and 6.49%, respectively. Predator-prey interactions, trophic cascading effects and competition of different components were also exhibited in the mixed trophic impacts map. Results from the network analysis suggested that the HZL ecosystem was a relatively mature ecosystem since the total primary production to respiration (TPP/TR) and to biomass (TPP/TB) were 1.138 and 6.922, and the Finn Cycling Index was 6.77%. Nevertheless, the relatively low values of Connectance Index (0.195) and System Omnivory Index (0.089), together with Finn's Mean path Length (2.849) also indicated that the food web structure was vulnerable, characterized by linear, rather than web-like features. Our results suggested that the HZL ecosystem would be potentially affected by the future inter-basin water diversion, and thus ecosystem-based strategies were also presented accordingly.
Afficher plus [+] Moins [-]INCREASE OF FERTILIZER NORMALS IN THE WATER TREATMENT ON THE EFFECTS OF FOOD ELEMENTS ON INCIDENTAL STEPS IN THE LOCAL POWER OF BITS Texte intégral
2018
Elkhan Allahverdiyev
Quantity of mineral elements in plants not the constant. Thus, the chemical compound of agricultural plants depends on their security mineral substances. The quantity of nutritious elements in a plant depends on soil-climatic conditions of territory, stages of development of grown up cultures, agricultural technicians, processings, degrees of security of soils nutrients, norms of fertilizers and other problems. Long-term researches show, that depending on an irrigation, norms of fertilizers and stages of development of plants, the quantity of nutritious elements at the mixed crops stubbles cultures differs in different bodies of plants. Are studied and analysed influence of norms of mineral and integrally-mineral fertilizers, proceeding from quantity various vegetative irrigation, on quantity of nutritious elements on stages of development of superficial weight of plants at mixed (corn and a soya) crops in stubbles plantings. Proceeding from quantity various vegetative irrigation and applications of various norms of fertilizers, from stage-bystage the analysis of nutrients in the mixed crops of plants it is visible, that the general NPK is observed on the highest phase stooling. From results of the analysis of samples of the plants taken at all stages, joint application of organic and mineral fertilizers in optimum norm becomes known, that, does not become the accumulation reason in considerable quantities of nutritious elements at the mixed crops of plants.
Afficher plus [+] Moins [-]Evaluar índices productivos en pollos alimentados con 5, 10 y 15 % lenteja de agua (<i>lemna minors</i>) fresca, reemplazando balanceado Texte intégral
2018
Bustamante Pizarro, Betty Yulissa | Vargas Gonzalez, Oliverio Napoleon
La producción avícola está considerada una de las mayores fuentes que proveen alimento para los consumidores, por lo tanto, los productores buscan nuevas fuentes alimenticias las cuales abaraten costos de producción, tanto en los sistemas de manejo como en la alimentación. Con este fin, se han creado nuevas formas de administración del alimento, como comederos automáticos en donde se puede añadir elementos al balanceado para ser consumido por parte del pollo, lo mismo sucede con el suministro de agua realizándose de forma automática o manual. La búsqueda de nuevas materias primas que otorguen una buena calidad nutricional en las aves de producción son variadas, en nuestro caso se ha considerado para realizar el presente estudio una planta acuática, una macrófita rica en proteína cruda (35%) la cual aporta al animal buenas cantidades de proteínas, aminoácidos y otros nutrientes que servirán para el desarrollo normal de las aves. Lemna minor, también conocida como lenteja de agua, es una planta acuática que crece en abundancia en lugares húmedos, templados, basando su replicación en agua estancada o circulante, contando con pH alrededor de 4,5 a 7,5, se adaptan a temperaturas de 15-24 °C. Esta materia prima fue recolectada en la estación piscícola “La Tembladera”, de la Universidad Técnica de Machala, ubicada en el Cantón Santa Rosa, la administración de Lemna minors en los pollos fue en diferentes cantidades (5, 10 y 15%) en reemplazo de alimento balanceado cuyo consumo se calculó basándose en las tablas de consumo de broiler en sus diferentes semanas de vida del ave. La Lemna minors fue mezclada conjuntamente por el porcentaje complementario de alimento balanceado, esta mezcla fue bien aceptada por parte del ave en un 100%. El estudio contó con 160 pollos broilers de 1 día de edad, los cuales fueron ubicados inmediatamente en una área condicionada, con el fin de proporcionar una temperatura mínima de 30°C y máxima de 32°C, durante la primera semana de vida, en este periodo se aclimatan las aves; a partir de la segunda semana se trabajó en el ensayo con 4 tratamientos denominados Tratamiento 1 (Lemna minors al 5%), Tratamiento 2 (Lemna minors al 10%), Tratamiento 3 (Lemna minors al 15%) y por último, el testigo, que contaba solo con la administración de alimento balanceado comercial y cada tratamiento tuvo 4 repeticiones homogéneas. La presente investigación fue realizada en las instalaciones avícolas de la Granja Santa Inés, correspondientes a la Unidad Académica de Ciencias Agropecuarias de la Universidad Técnica de Machala. Las variables a estudiar son: ganancia de peso, consumo alimenticio, conversión alimenticia (rendimiento de carcaza), índices de mortalidad; además de valorar el costo de producción determinándose cada resultado por separado en relación a los diferentes valores o resultados obtenidos por tratamiento, atribuyendo dicha actividad a la materia prima en estudio, Lemna minor en el organismo del pollo modificando las características medibles y observables, además analizar los indicadores organolépticos con los criterios obtenidos de 120 personas que participaron en la cata en las instalaciones de la Unidad Académica de Ciencias Agropecuarias. | Poultry production is considered one of the largest sources that provide food for consumers, therefore, producers seek new food sources which lower production costs, both in management systems and in food. To this end, new forms of food administration have been created, such as automatic feeders, where elements can be added to the balance to be consumed by the chicken, the same happens with the water supply being made automatically or manually. The search for new raw materials that provide a good nutritional quality in the production birds are varied. In our case, an aquatic plant, a macrophyte rich in crude protein (35%) which contributes to the animal, has been considered for the present study. good amounts of proteins, amino acids and other nutrients that will serve for the normal development of birds. Lemna minor, also known as duckweed, is an aquatic plant that grows in abundance in humid, temperate places, basing its replication in stagnant or circulating water, counting with pH around 4.5 to 7.5, adapting to temperatures 15-24 ° C. This raw material was collected in the fish station "La Tembladera", of the Technical University of Machala, located in the Canton Santa Rosa, the administration of Lemna minors in the chickens was in different quantities (5, 10 and 15%) in replacement of balanced feed whose consumption was calculated based on the broiler consumption tables in their different weeks of the bird's life. The Lemna minors was mixed together by the complementary percentage of balanced feed, this mixture was well accepted by the bird in 100%. The study included 160 1-day-old broiler chickens, which were immediately placed in a conditioned area, in order to provide a minimum temperature of 30 ° C and a maximum temperature of 32 ° C, during the first week of life, in this period the birds are acclimatized; from the second week we worked on the trial with 4 treatments called Treatment 1 (Lemna minors at 5%), Treatment 2 (Lemna minors at 10%), Treatment 3 (Lemna minors at 15%) and finally, the control , that had only the administration of commercial balanced feed and each treatment had 4 homogeneous repetitions. The present investigation was carried out in the poultry facilities of Granja Santa Inés, corresponding to the Academic Unit of Agricultural Sciences of the Technical University of Machala. The variables to be studied are: weight gain, food consumption, feed conversion (carcass yield), mortality rates; in addition to assessing the cost of production, each result being determined separately in relation to the different values or results obtained by treatment, attributing said activity to the raw material under study, Lemna minor in the organism of the chicken, modifying the measurable and observable characteristics, and analyzing the organoleptic indicators with the criteria obtained from 120 people who participated in the tasting in the facilities of the Academic Unit of Agricultural Sciences.
Afficher plus [+] Moins [-]Optimization of Solvent Terminated Dispersive Liquid–Liquid Microextraction of Copper Ions in Water and Food Samples Using Artificial Neural Networks Coupled Bees Algorithm Texte intégral
2018
Farajvand, Mohammad | Kiarostami, Vahid | Davallo, Mehran | Ghaedi, Abdolmohammad
A multivariate method based on solvent terminated dispersive liquid–liquid microextraction was developed for the determination of Cu²⁺ ions in aqueous samples. In the proposed approach, di-2-ethylhexylphosphoric acid, xylene and acetone were used as chelating agent, dispersive and extraction solvents, respectively. The effects of various factors on the extraction efficiency such as extraction and dispersive solvent volumes, salt addition and pH were studied using central composite design (CCD) and artificial neural networks coupled bees algorithm (ANN-BA). Upon comparison of these techniques, ANN-BA model was considered to be better optimization method due to its higher percentage relative recovery (about 5%) as compared to the CCD approach. The linear range and the limits of detection (S/N = 3) and quantitation (S/N = 10) were 0.22–140, 0.08 and 0.22 µg L⁻¹, respectively. Under the optimal conditions, the recoveries for real samples spiked with 0.1 and 0.3 mg L⁻¹ were in the range of 85–98%.
Afficher plus [+] Moins [-]Do Sanitation Improvements Reduce Fecal Contamination of Water, Hands, Food, Soil, and Flies? Evidence from a Cluster-Randomized Controlled Trial in Rural Bangladesh Texte intégral
2018
Ercumen, Ayse | Pickering, Amy J. | Kwong, Laura H. | Mertens, Andrew | Arnold, Benjamin F. | Benjamin-Chung, Jade | Hubbard, Alan E. | Alam, Mahfuja | Sen, Debashis | Islam, Sharmin | Rahman, Md Zahidur | Kullmann, Craig | Chase, Claire | Ahmed, Rokeya | Parvez, Sarker Masud | Unicomb, Leanne | Rahman, Mahbubur | Ram, Pavani K. | Clasen, Thomas | Luby, Stephen P. | Colford, John M.
Sanitation improvements have had limited effectiveness in reducing the spread of fecal pathogens into the environment. We conducted environmental measurements within a randomized controlled trial in Bangladesh that implemented individual and combined water treatment, sanitation, handwashing (WSH) and nutrition interventions (WASH Benefits, NCT01590095). Following approximately 4 months of intervention, we enrolled households in the trial’s control, sanitation and combined WSH arms to assess whether sanitation improvements, alone and coupled with water treatment and handwashing, reduce fecal contamination in the domestic environment. We quantified fecal indicator bacteria in samples of drinking and ambient waters, child hands, food given to young children, courtyard soil and flies. In the WSH arm, Escherichia coli prevalence in stored drinking water was reduced by 62% (prevalence ratio = 0.38 (0.32, 0.44)) and E. coli concentration by 1-log (Δlog₁₀ = −0.88 (−1.01, −0.75)). The interventions did not reduce E. coli along other sampled pathways. Ambient contamination remained high among intervention households. Potential reasons include noncommunity-level sanitation coverage, child open defecation, animal fecal sources, or naturalized E. coli in the environment. Future studies should explore potential threshold effects of different levels of community sanitation coverage on environmental contamination.
Afficher plus [+] Moins [-]At the Intersection of Urbanization, Water, and Food Security: Determination of Select Contaminants of Emerging Concern in Mussels and Oysters from Hong Kong Texte intégral
2018
Burket, S Rebekah | Sapozhnikova, Yelena | Zheng, J. S. | Chung, Shan Shan | Brooks, Bryan W.
Aquaculture, which is growing 3–5 times faster than terrestrial agriculture, will play an important role to meet future global food production needs. However, over 80% of global sewage production is returned to the environment untreated or poorly treated. In developing nations, these nontraditional waters of diverse quality are being recycled for aquaculture, yet chemical residues are differentially studied. Here, we examined pharmaceuticals, pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), and flame retardants in marine bivalves using isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) and low-pressure gas chromatography-tandem mass spectrometry (LP GC-MS/MS). Green-lipped mussels from the field and oysters from aquaculture net pens, which are harvested as food products, were collected adjacent to point source municipal wastewater and landfill leachate effluent discharges, respectively, in Hong Kong, the fourth most densely populated country in the world. Multiple classes of pharmaceutical, pesticides, PAHs, and phosphorus-based flame retardants were detected at low μg/kg levels. Acceptable servings per week indicated minimal risk for a number of chemicals; however, such calculations could not be performed for other contaminants of emerging concern. Future efforts are needed to better understand contaminant influences on marine bivalve populations and aquaculture product safety, particularly in rapidly urbanizing regions of developing countries with limited wastewater infrastructure.
Afficher plus [+] Moins [-]Erratum to: “MnO2/3MgO Nanocomposite for Preconcentration and Determination of Trace Copper and Lead in Food and Water by Flame Atomic Absorption Spectrometry” Texte intégral
2018
Khayatian, Gholamreza | Moradi, Marzieh | Hassanpoor, Shahed
In Figure 4: should read “Nitric acid (0.1 M)” instead of “Nutric acid (0.1 M)”Figure 6 should be:
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