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Central Asia’s Ili River Ecosystem as a Wicked Problem: Unraveling Complex Interrelationships at the Interface of Water, Energy, and Food 全文
2018
Steven G. Pueppke | Sabir T. Nurtazin | Norman A. Graham | Jiaguo Qi
The Ili River originates in the mountains of Xinjiang, China, and flows across an increasingly arid landscape before terminating in Kazakhstan&rsquo:s Lake Balkhash, which has no outlet to the ocean. The river has been extensively impounded and diverted over the past half century to produce hydroelectric power and food on irrigated land. Water withdrawals are increasing to the extent that they are beginning to threaten the ecosystem, just as it is becoming stressed by altered inflows as glaciers retreat and disappear. If the Ili River ecosystem is to be preserved, it is crucial that we thoroughly understand the spatial and temporal nuances of the interrelationships between water, energy, and food&mdash:and the vulnerability of these components to climate change. The ecosystem has all of the characteristics of a classically-defined &ldquo:wicked problem&rdquo:, and so it warrants treatment as a complex and dynamic challenge subject to changing assumptions, unexpected consequences, and strong social and economic overtones. Research should thus focus not just on new knowledge about the water, energy, or food component, but on advancing our understanding of the ecosystem as a whole. This will require the participation of interdisciplinary teams of researchers with both tacit and specialized knowledge.
显示更多 [+] 显示较少 [-]Comportamento ingestivo e termorregulação em ovinos alimentados com silagem de palma forrageira submetidos a oferta intermitente de água 全文
2018
Ismael de Sousa Nobre | Gherman Garcia Leal de Araújo | Edson Mauro Santos | Gleidson Giordano Pinto de Carvalho | Bonifácio Benicio de Souza | Ossival Lolato Ribeiro | Silvia Helena Nogueira Turco | Anderson Barbosa Cavalcante | Italo Reneu Rosas de Albuquerque
Objetivou-se avaliar o efeito da utilização de silagem de palma forrageira na dieta de ovinos submetidos a oferta intermitente de água sobre o comportamento ingestivo e a termorregulação de ovinos. Foram utilizados 36 ovinos machos não castrados sem padrão racial, com peso médio inicial de 19,8 + 2,1 kg e idade aproximada de seis meses, distribuídos em delineamento de blocos ao acaso, em esquema fatorial 3 x 3, composto por três proporções de silagem de palma na dieta (0; 21 e 42 %) e três períodos de oferta de água (0; 24 e 48 horas), com quatro repetições. Para o comportamento ingestivo foram realizadas observações a cada 5 minutos durante 2 períodos de 24 horas. As respostas termorregulatórias foram tomadas nos horários das 7 e 15 horas, em dias diferentes daqueles destinados ao comportamento. Observou-se que a oferta intermitente de água não afetou nenhuma das variáveis estudadas (P > 0,05). A utilização de silagem de palma influenciou significativamente o comportamento ingestivo dos animais (P < 0,05). Ovinos alimentados com silagem de palma forrageira na dieta apresentaram eficiência de alimentação média de 255,77 gMS h-1 e de ruminação de 102,16 gMS h-1, enquanto que aqueles que não recebiam esse alimento, apresentaram valores dessas variáveis de 198,63 e 78,45 gMS h-1, respectivamente. A frequência urinária dos animais se elevou conforme a proporção de silagem de palma na dieta, sendo observadas 23,60 micções dia-1 em animais que recebiam 42% e 10,83 micções dia-1 naqueles que não recebiam silagem de palma. A procura por água, entretanto, diminuiu. Foram observadas médias de 2,73 e 0,54 (nº dia-1) para animais alimentados com 0 e 42% de silagem de palma, respectivamente. A utilização da silagem de palma também elevou as respostas termorregulatórias dos ovinos. Ovinos alimentados com silagem de palma apresentaram média de frequência respiratória de 103,35 e cardíaca de 140,08 movimentos minuto-1 no período mais quente do dia (tarde). Concluiu-se que a silagem de palma na dieta aumenta as eficiências de alimentação e ruminação, além de diminuir a procura por água em ovinos em confinamento. No entanto, também eleva suas respostas termorregulatórias. A oferta intermitente de água em até 48 horas não influencia o comportamento ingestivo e a termorregulação de ovinos em confinamento.
显示更多 [+] 显示较少 [-]Milho crioulo e melhorado: tolerância a deficiência hídrica na perspectiva da segurança e soberania alimentar | Landrace and improved: tolerance to water defcit on a perspective of food security 全文
2018
Langner, Josana Andreia | Streck, Nereu Augusto | http://lattes.cnpq.br/8121082379157248 | Alberto, Cleber Maus | http://lattes.cnpq.br/2747295128900648 | Tironi, Luana Fernandes | http://lattes.cnpq.br/9454013527647467 | Reiniger, Lia Rejane Silveira | http://lattes.cnpq.br/5739294882585391 | Petry, Mirta Teresinha | http://lattes.cnpq.br/0358609083747198
The objectives of this thesis were to (i) discuss the importance of maize crop nowadays and its crucial role in the future for food production in scenarios of water defcit, and its importance in the conservation of landrace cultivars, which hold a considerable part of this reserve of genetic variability and (ii) to compare the tolerance to water defcit of improved and landrace, maize cultivars in the field and in rain exclused environment and to determine FATS threshold in the reproductive period. Information from the temperature shows that in several places, with the aid of the Genetic Improvement, the characteristic of plants that lead to drought tolerance were established. It is concluded that for a cultivar to be accepted by the farmers, in addition to the adaptation characteristics, it must have a high grain yield and information needs to be disclosed. To quantify the tolerance of local cultivars, field experiments were conducted in the 2015/2016, 2016/2017 and 2016/2017, 2017/2018 growing season for FTSW in the experimental area of the Plant Science Department at UFSM, Santa Maria, RS. The landraces cultivars presented similar yield in the irrigated and non irrigated system, while the improved cultivars increased yield in the irrigated. For FTSW, 'AS 1573PRO' and 'Cinquentinha' presented similar values in the first year, and 'Bico de ouro' was smaller. In the second year 'AS 1573PRO' presented FTSW, followed by 'Cinquentinha' and again smaller 'Bico de ouro'. The cultivar 'AS 1573PRO' had the highest tolerance indicated by FTSW, in a short period of deficiency. The 'Cinquentinha' showed a smaller tolerance for FTSW, but as indicated by gas exchange measurements under conditions with prolonged water stress, it is more tolerant, producing ears with grains even under extreme conditions of water deficit in the FATS experiment. | Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES | Os principais objetivos deste trabalho foram (i) discutir a importância da cultura do milho na atualidade e o papel crucial que pode desempenhar no futuro para a produção de alimentos em cenários de deficiência hídrica, bem como, a importância de conservar as cultivares crioulas, que detêm uma parcela considerável dessa reserva de variabilidade genética e (ii) comparar a tolerância à deficiência hídrica de cultivares melhoradas e crioulas de milho em campo e em ambiente de exclusão de chuva determinar a Fração de Água Transpirável no Solo (FATS na fase reprodutiva. As informações reunidas demostram que, em vários locais, com o auxílio do Melhoramento Genético, foram fixadas nas plantas características que conferem tolerância a deficiência hídrica. Conclui-se que, para uma cultivar ser aceita pelos produtores, além das características de adaptação, precisa ter alta produção de grãos e informações dessas características precisam ser divulgadas. Para conhecer a tolerância de cultivares com diferente variabilidade genética, foram conduzidos experimentos de campo nos anos agrícolas 2015/2016, 2016/2017 e 2016/2017, 2017/2018 para a FATS, na área experimental do Departamento de Fitotecnia da UFSM, Santa Maria, RS. Pelo experimento no campo foi possível verificar que as cultivares crioulas apresentaram produtividade similar no sistema irrigado e não irrigado, enquanto as melhoradas demostraram aumento sob irrigação. Para a FATS, o ‘AS 1573PRO’ e ‘Cinquentinha’ apresentaram valores similares no primeiro ano, e ‘Bico de ouro’, menor; já no segundo ano ‘AS 1573PRO’ apresentou maior FATS, seguido pela ‘Cinquentinha’ e, novamente, menor a ‘Bico de ouro’. A cultivar ‘AS 1573PRO’ possui maior tolerância indicada pela FATS, quando se trata de um período curto de deficiência. ‘Cinquentinha’ demostrou tolerância menor pela FATS, porém como indicado pelas medidas de trocas gasosas, em condições com estresse hídrico prolongado, é mais tolerante. Esta cultivar crioula produz grãos mesmo em condições extremas de deficiência hídrica.
显示更多 [+] 显示较少 [-]The Implementation and Food Safety Issues Associated With Poultry Processing Reuse Water for Conventional Poultry Production Systems in the United States 全文
2018
Andrew C. Micciche | Kristinia M. Feye | Peter M. Rubinelli | Jennifer A. Wages | Carl J. Knueven | Steven C. Ricke
As human populations increase in numbers, access to clean, fresh water is becoming increasingly difficult to balance between agricultural and municipal demands. Water scarcity is a limiting factor of food production in many countries, whether they are emerging or established economies. In conventional poultry processing systems, access to water is particularly critical for the maintenance and disinfection of processing areas, as well as in processing operations such as scalding, chilling, and carcass washing. Therefore, poultry processing plants use an excessive amount of water, limiting where facilities can operate, increasing overhead costs, and ultimately resulting in potential environmental concerns. The need for sustainable alternatives to single-use water supplies is becoming increasingly more urgent. As a result, the implementation of water reuse in poultry-processing plants has emerged as an attractive alternative means to meet water requirements during processing. Because the water is reused, it is essential to de-contaminate the water with chemicals, such as peracetic acid and chlorine, and improve water filtration strategies to kill and remove potential pathogens and contaminants. However, questions remain as to the efficacy of commonly used disinfectants to achieve that goal. Thus, novel strategies must be developed to improve the capabilities of poultry processing plants to counter water insecurity worldwide. These new stratagems must be economical and enable poultry processing plants to reduce their environmental footprint while meeting new food safety challenges. The current review will focus exclusively on water reuse in conventional poultry processing in the United States. The specific objectives of this review are to discuss the approaches for treating processing water in poultry processing systems, including reuse water systems, as well as investigate possible substitutes for maintaining food safety.
显示更多 [+] 显示较少 [-]Quantifying and evaluating the impacts of cooperation in transboundary river basins on the Water-Energy-Food nexus: The Blue Nile Basin 全文
2018
Basheer, Mohammed | Wheeler, Kevin G. | Ribbe, Lars | Majdalawi, Mohammad | Abdo, Gamal | Zagona, Edith A.
Efficient utilization of the limited Water, Energy, and Food (WEF) resources in stressed transboundary river basins requires understanding their interlinkages in different transboundary cooperation conditions. The Blue Nile Basin, a transboundary river basin between Ethiopia and Sudan, is used to illustrate the impacts of cooperation between riparian countries on the Water-Energy-Food nexus (WEF nexus). These impacts are quantified and evaluated using a daily model that simulates hydrological processes, irrigation water requirements, and water allocation to hydro-energy generation and irrigation water supply. Satellite-based rainfall data are evaluated and applied as a boundary condition to model the hydrological processes.The model is used to determine changes in the long-term economic gain (i.e. after infrastructure development plans are implemented and in steady operation) for each of Sudan and Ethiopia independently, and for the Blue Nile Basin from WEF in 120 scenarios. Those scenarios result from combinations of three cooperation states: unilateral action, coordination, and collaboration; and infrastructure development settings including the Grand Ethiopian Renaissance Dam and planned irrigation schemes in Sudan. The results show that the economic gain of the Blue Nile Basin from WEF increases with raising the cooperation level between Ethiopia and Sudan to collaboration. However, the economic gain of each riparian country does not necessarily follow the same pattern as the economic gain of the basin.
显示更多 [+] 显示较少 [-]Water-energy-food nexus of sugarcane ethanol production in the state of Goiás, Brazil: An analysis with regional input-output matrix 全文
2018
Bellezoni, Rodrigo A. | Sharma, Deepak | Villela, Alberto Arruda | Pereira Junior, Amaro Olimpio
Concerns about impacts of biomass growth for biofuel production emphasize the importance of planning energy crops expansion considering land, water, food and biodiversity. Brazil is the second largest ethanol producer worldwide and sugarcane is cultivated in many regions, including the Brazilian Cerrado (a Savannah-type biome). This paper analyses the impacts of first-generation sugarcane expansion in the Paranaíba basin (Goiás State), focusing on how future demand for ethanol could affect local resources availability. The study area is a sugarcane expansion frontier in Brazil, thus, the Cerrado biome should be focus of research considering competition for land and water uses. An economic-ecologic Input-Output (IO) framework was applied to develop a water-energy-food (WEF) nexus analysis. The Goiás’ IO table was expanded to assess water, energy and land uses, GHG emissions and employment levels through six different ethanol supply scenarios.Results show that if sugarcane expansion projected to 2030 considers the Goiás’ extended IO structure for the year 2008, it should cause little impact on land and water availability in the state, due to both the ample availability of suitable pasturelands for sugarcane expansion as well as water in most of the Paranaíba basin. The WEF nexus analysis is a valuable tool on guiding the sustainable management of natural resources considering water, energy, land use and GHG emissions as goals to the same policy. In particular, the hybrid extended IO-WEF nexus framework is useful to design effective biofuel policies, collectively addressing impacts on environmental, social and economic spheres, in a local or broader context.
显示更多 [+] 显示较少 [-]MnO2/3MgO Nanocomposite for Preconcentration and Determination of Trace Copper and Lead in Food and Water by Flame Atomic Absorption Spectrometry 全文
2018
Khayatian, Gholamreza | Moradi, Marzieh | Hassanpoor, Shahed
The presented study investigates the application of MnO₂/3MgO nanocomposite, as a new sorbent for solid phase extraction and determination of trace amounts of Pb²⁺ and Cu²⁺ from various samples using flame atomic absorption spectrometry. After extraction, the analytes were desorbed using 0.01 M ethylenediaminetetraacetic acid. The effects of various parameters were studied and optimized. Under optimized experimental conditions the linear dynamic ranges for Cu²⁺ and Pb²⁺ were 10‒900 and 30‒900 μg/L, respectively, with a preconcentration factor of 20. The detection limits of Cu²⁺ and Pb²⁺ were 4 and 11 μg/L, respectively, and relative standard deviations for eight determinations of 100 μg/L were 3.6 and 3.8% for Cu²⁺ and Pb²⁺, respectively. The method was successfully applied for determination of copper and lead in mushrooms, rice, tap water and refinery wastewater with good spike recoveries ranging between 95‒106%.
显示更多 [+] 显示较少 [-]Advising Morocco: adopting recommendations of a water footprint assessment would increase risk and impair food security for the country and its farmers 全文
2018
Wichelns, Dennis
A water footprint assessment is not an appropriate guide for allocating water efficiently in water-scarce regions such as Morocco. Water footprints contain too little information to identify policies or investments that will achieve public goals regarding agriculture, natural resources and livelihoods. In fact, they would impair efforts to enhance food security and sustain economic growth. The better way forward for Morocco and other countries is to analyze the full range of economic, social and environmental issues pertaining to water use in agriculture and other sectors.
显示更多 [+] 显示较少 [-]Influence of water temperature and food on the last stages of cultured pearl mineralization from the black-lip pearl oyster Pinctada margaritifera 全文
2018
Latchere, Oihana | Mehn, Vincent | Gaertner-mazouni, Nabila | Le Moullac, Gilles | Fievet, Julie | Belliard, Corinne | Cabral, Philippe | Saulnier, Denis
Environmental parameters, such as food level and water temperature, have been shown to be major factors influencing pearl oyster shell growth and molecular mechanisms involved in this biomineralization process. The present study investigates the effect of food level (i.e., microalgal concentration) and water temperature, in laboratory controlled conditions, on the last stages of pearl mineralization in order to assess their impact on pearl quality. To this end, grafted pearl oysters were fed at different levels of food and subjected to different water temperatures one month prior to harvest to evaluate the effect of these factors on 1) pearl and shell deposition rate, 2) expression of genes involved in biomineralization in pearl sacs, 3) nacre ultrastructure (tablet thickness and number of tablets deposited per day) and 4) pearl quality traits. Our results revealed that high water temperature stimulates both shell and pearl deposition rates. However, low water temperature led to thinner nacre tablets, a lower number of tablets deposited per day and impacted pearl quality with better luster and fewer defects. Conversely, the two tested food level had no significant effects on shell and pearl growth, pearl nacre ultrastructure or pearl quality. However, one gene, Aspein, was significantly downregulated in high food levels. These results will be helpful for the pearl industry. A wise strategy to increase pearl quality would be to rear pearl oysters at a high water temperature to increase pearl growth and consequently pearl size; and to harvest pearls after a period of low water temperature to enhance luster and to reduce the number of defects.
显示更多 [+] 显示较少 [-]Fabricating a new electrochemically modified pencil graphite electrode based on acetophenone (2,4-dinitrophenyl)hydrazone for determining selenium in food and water samples 全文
2018
Azizi, Zohreh | Babakhanian, Arash
Determination of selenium compounds in air, soil, water, and food samples is of interest as selenium's bioavailability and toxicity depend on its concentration level. Among analytical approaches, electrochemical sensors are more favorable due to their simplicity, time-saving, cost-effectiveness, and high sensitivity. In this study, we report electrochemical determination and analysis of selenium at the surface of a pencil graphite electrode modified with a sensing composite film composed of acetophenone (2,4-dinitrophenyl)hydrazone, polypyrrole, and copper nanoparticles. To produce durable films, cyclic voltammetry technique, as a facile modification procedure, was used. The electrochemical response of the fabricated modified electrode to selenium was evaluated using cyclic and square wave voltammetry techniques. The modified electrode presented excellent electrocatalytic ability with favorable electrochemical parameters (α = 0.24, log kₛ = 3.27 s⁻¹, and Γ = 3.74 × 10⁻⁷ mmol cm⁻²) for the reduction of selenium in acidic media with optimized pH of 2 and working potential of around −0.85 V (vs. SCE). The scanning electron microscopy images of the modified surfaces proved the formation of aggregates in nanoscale, indicating successful electrodeposition and electro-polymerization processes to modify the pencil graphite surface. This revealed a linear electrochemical response to selenium within the concentration range from 50 nM to 110 nM with the limit of detection (LOD) of 16.58 nM. The analytical application of the new sensor was also examined with respect to its applicability in food samples, such as milk, and water samples, including food wastewater samples, suggesting valid determination of selenium without any side interference.
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