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An innovative accounting framework for the food-energy-water nexus
2013
Giampietro, M (Mario)
Perfluoroalkyl substances (PFASs) in food and water from Faroe Islands 全文
2013
Diet and drinking water are suggested to be major exposure pathways for perfluoroalkyl substances (PFASs). In this study, food items and water from Faroe Islands sampled in 2011/2012 were analyzed for 11 perfluoroalkyl carboxylic acids (PFCAs) and 4 perfluoroalkane sulfonic acids (PFSAs). The food samples included milk, yoghurt, crème fraiche, potatoes, fish, and fish feed, and the water samples included surface water and purified drinking water. In total, nine PFCAs and four PFSAs were detected. Generally, the levels of PFAS were in the lower picogram per gram range. Perfluorobutanoic acid was a major contributor to the total PFASs concentration in water samples and had a mean concentration of 750 pg/L. Perfluoroundecanoic acid (PFUnDA) was predominating in milk and wild fish with mean concentrations of 170 pg/g. Perfluorooctane sulfonic acid (PFOS) was most frequently detected in food items followed by PFUnDA, perfluorononanoic acid, and perfluorooctanoic acid (PFOA). Levels of PFUnDA and PFOA exceeded those of PFOS in milk and fish samples. Prevalence of long-chain PFCAs in Faroese food items and water is confirming earlier observations of their increase in Arctic biota. Predominance of short-chain and long-chain homologues indicates exposure from PFOS and PFOA replacement compounds.
显示更多 [+] 显示较少 [-]Water, food and markets : household-level impact of irrigation water policies and institutions in northern China
2013
Zhang, L.
Water is increasingly becoming a limiting factor for sustainable economic growth and development, particularly in developing countries. Besides technical innovations, water institution reforms may contribute to improving water allocation decisions. Appropriately designed water institutions can motivate water users to conserve and use water efficiently for irrigation and other uses. In northern China, growing demands on agricultural water due to relatively low water availability and increasing grain production are putting more and more pressure on improving water resource management. The Ministry of Water Resources of the P.R. China has initiated a number of pilot projects to gain experience with the development of water-saving irrigation systems. These pilot projects focus on the construction of engineering systems as well as institutional innovations in water resource management. Analysing the household-level effects of the implemented measures is hence of great importance for further policy development. The project ‘Building a Water-saving Society in Zhangye City’, initiated early 2002 in Zhangye City in northwest China, is the first pilot project of this kind in China. It provides a unique opportunity to examine the economic effects of changes in water policies and institutions. Minle County, the research area for this study, is located within Zhangye City. A large potato processing company was established in Minle County in 2008. After the factory started its activities, the local government intervened in the allocation of irrigation water within the region by assigning more water to a specific variety of potatoes (i.e. Atlantic potatoes) that the factory needs for processing. This further makes Minle County an interesting case for analysing the link between output market development and institutional change in irrigation water management. The general objective of this study is to empirically investigate the household-level impacts of policies and institutional changes in irrigation water use. From this general objective, the following four specific objectives are defined and analysed in separate chapters. 1) To examine the impact of the institutional setup of Water Users Associations (WUAs) on productivity of irrigation water use by the WUA member households, based on a user-based resource governance framework. 2) To analyse the effects of a policy affecting the availability of water for different crops on farmers’ acreage allocation among crops. 3) To evaluate the internal valuation (i.e. marginal value) of irrigation water, before and after the introduction of the water policy as explained above. 4) To investigate the effects of output market development on irrigation water trading. The information used for the empirical analyses mainly comes from two surveys that were carried out in Minle County in May 2008 and May 2010. These surveys cover information for the years 2007 and 2009, that is before and after the potato processing factory became operational. A stratified sampling approach was used for selecting the households and WUAs to be interviewed in the surveys. Additional interviews were held by the author in August 2010 with the Water Management Bureaus (WMBs) that are responsible for water allocation within the seven irrigation areas in Minle County. Chapter 2 investigates the underlying causes of differences in WUA performance by analysing the impact of WUA characteristics on the productivity of irrigation water use. Total crop production value and household income obtained from crop production, both expressed per m<sup>3</sup> of water, are used as dependent variables in the empirical analysis. The explanatory variables in the analysis are derived from an established user-based resource governance framework, that specifies the conditions under which user groups are expected to sustainably govern common-pool resources. These conditions are grouped into resource characteristics, group characteristics, relationships between resources and user groups, and the external environment (markets, technology). Applying a random intercept model, the estimation results show that group characteristics, particularly group size and number of water users groups, and the existing pressure on available water resources are important WUA characteristics explaining water productivity. Chapter 3 analyses the impact of the local government intervention in irrigation water allocation on farmers’ crop planting decisions. A system of unconditional crop acreage demand functions depending on prices of variable inputs, levels of quasi-fixed inputs and prices of outputs is estimated. Two hypotheses are tested: Firstly, the government intervention results in an increase in land allocated to Atlantic potatoes and a decrease in land allocated to other crops; Secondly, among the alternative crops (i.e. other crops than Atlantic potatoes), the water policy is expected to cause a relatively small response for grain crops, because grains are mainly used for domestic consumption. The empirical results do not support the first hypothesis. The increased water allocation to Atlantic potatoes does not significantly affect the land allocated to this crop, because its planting decisions are mainly taken by village leaders instead of households. Instead, the intervention results in a shift from planting potatoes towards grains with relatively low water requirements.The second hypothesis is partly supported by the empirical results. The estimated impact of the government intervention is found to be stronger for local potato varieties than for grains, but the impact on the area planted with cash crops does not differ significantly from zero. Output prices seem to play a more important role in cash crop planting decisions than the water allocation intervention. Chapter 4 examines the economic valuation (i.e. marginal value) of irrigation water, before and after the local government intervention in water allocation. To accomplish this, a system of translog production functions is estimated. Two hypotheses are tested: Firstly, the valuation of irrigation water is expected to be equal across different crops before the start of the new water policy. And secondly, valuation of irrigation water is expected to be lower for Atlantic potatoes as compared to the alternative crops after the water policy change. The empirical results do not support the first hypothesis. The valuation of irrigation water used on grain crops is very low, and is even below the actual water prices charged to farm households. This is probably due to self-consumption of grain by households, and to government subsidies for grain farmers that are based on the planted area with grains. The second hypothesis is supported by the empirical results, except for grains. The valuation of irrigation water used on Atlantic potatoes is lower than the value of water used on other (non-grain) crops. Moreover, the returns for irrigation water used on other crops are higher in the year after the water allocation intervention than in the year before the intervention. Chapter 5 aims to provide insights into the impact of output market development on the trading of water use rights by farm households. Theresults of the two farm household surveys indicate that water markets have emerged at a small scale in response to the development of the potato market in Minle County. Observed water trade in the second survey, that was held after the establishment of the potato processing factory, consists mainly of the exchange of water without payment between relatives or neighbours, and seems to be meant to improve the timing of water applications to crops with different seasonal water requirements. Those who have started trading water rights tend to have more land with water use rights than other potato farmers. High transaction costs and information asymmetry between the government and water users, however, severely constrain the trading of water use rights in the region. Chapter 6 summarizes and integrates the main findings, discusses the policy implications and the limitations of the research, and presents some suggestions for further research.
显示更多 [+] 显示较少 [-]Water, food and markets : household-level impact of irrigation water policies and institutions in northern China 全文
2013
Zhang, L.
Water is increasingly becoming a limiting factor for sustainable economic growth and development, particularly in developing countries. Besides technical innovations, water institution reforms may contribute to improving water allocation decisions. Appropriately designed water institutions can motivate water users to conserve and use water efficiently for irrigation and other uses. In northern China, growing demands on agricultural water due to relatively low water availability and increasing grain production are putting more and more pressure on improving water resource management. The Ministry of Water Resources of the P.R. China has initiated a number of pilot projects to gain experience with the development of water-saving irrigation systems. These pilot projects focus on the construction of engineering systems as well as institutional innovations in water resource management. Analysing the household-level effects of the implemented measures is hence of great importance for further policy development. The project ‘Building a Water-saving Society in Zhangye City’, initiated early 2002 in Zhangye City in northwest China, is the first pilot project of this kind in China. It provides a unique opportunity to examine the economic effects of changes in water policies and institutions. Minle County, the research area for this study, is located within Zhangye City. A large potato processing company was established in Minle County in 2008. After the factory started its activities, the local government intervened in the allocation of irrigation water within the region by assigning more water to a specific variety of potatoes (i.e. Atlantic potatoes) that the factory needs for processing. This further makes Minle County an interesting case for analysing the link between output market development and institutional change in irrigation water management. The general objective of this study is to empirically investigate the household-level impacts of policies and institutional changes in irrigation water use. From this general objective, the following four specific objectives are defined and analysed in separate chapters. 1) To examine the impact of the institutional setup of Water Users Associations (WUAs) on productivity of irrigation water use by the WUA member households, based on a user-based resource governance framework. 2) To analyse the effects of a policy affecting the availability of water for different crops on farmers’ acreage allocation among crops. 3) To evaluate the internal valuation (i.e. marginal value) of irrigation water, before and after the introduction of the water policy as explained above. 4) To investigate the effects of output market development on irrigation water trading. The information used for the empirical analyses mainly comes from two surveys that were carried out in Minle County in May 2008 and May 2010. These surveys cover information for the years 2007 and 2009, that is before and after the potato processing factory became operational. A stratified sampling approach was used for selecting the households and WUAs to be interviewed in the surveys. Additional interviews were held by the author in August 2010 with the Water Management Bureaus (WMBs) that are responsible for water allocation within the seven irrigation areas in Minle County. Chapter 2 investigates the underlying causes of differences in WUA performance by analysing the impact of WUA characteristics on the productivity of irrigation water use. Total crop production value and household income obtained from crop production, both expressed per m3 of water, are used as dependent variables in the empirical analysis. The explanatory variables in the analysis are derived from an established user-based resource governance framework, that specifies the conditions under which user groups are expected to sustainably govern common-pool resources. These conditions are grouped into resource characteristics, group characteristics, relationships between resources and user groups, and the external environment (markets, technology). Applying a random intercept model, the estimation results show that group characteristics, particularly group size and number of water users groups, and the existing pressure on available water resources are important WUA characteristics explaining water productivity. Chapter 3 analyses the impact of the local government intervention in irrigation water allocation on farmers’ crop planting decisions. A system of unconditional crop acreage demand functions depending on prices of variable inputs, levels of quasi-fixed inputs and prices of outputs is estimated. Two hypotheses are tested: Firstly, the government intervention results in an increase in land allocated to Atlantic potatoes and a decrease in land allocated to other crops; Secondly, among the alternative crops (i.e. other crops than Atlantic potatoes), the water policy is expected to cause a relatively small response for grain crops, because grains are mainly used for domestic consumption. The empirical results do not support the first hypothesis. The increased water allocation to Atlantic potatoes does not significantly affect the land allocated to this crop, because its planting decisions are mainly taken by village leaders instead of households. Instead, the intervention results in a shift from planting potatoes towards grains with relatively low water requirements.The second hypothesis is partly supported by the empirical results. The estimated impact of the government intervention is found to be stronger for local potato varieties than for grains, but the impact on the area planted with cash crops does not differ significantly from zero. Output prices seem to play a more important role in cash crop planting decisions than the water allocation intervention. Chapter 4 examines the economic valuation (i.e. marginal value) of irrigation water, before and after the local government intervention in water allocation. To accomplish this, a system of translog production functions is estimated. Two hypotheses are tested: Firstly, the valuation of irrigation water is expected to be equal across different crops before the start of the new water policy. And secondly, valuation of irrigation water is expected to be lower for Atlantic potatoes as compared to the alternative crops after the water policy change. The empirical results do not support the first hypothesis. The valuation of irrigation water used on grain crops is very low, and is even below the actual water prices charged to farm households. This is probably due to self-consumption of grain by households, and to government subsidies for grain farmers that are based on the planted area with grains. The second hypothesis is supported by the empirical results, except for grains. The valuation of irrigation water used on Atlantic potatoes is lower than the value of water used on other (non-grain) crops. Moreover, the returns for irrigation water used on other crops are higher in the year after the water allocation intervention than in the year before the intervention. Chapter 5 aims to provide insights into the impact of output market development on the trading of water use rights by farm households. Theresults of the two farm household surveys indicate that water markets have emerged at a small scale in response to the development of the potato market in Minle County. Observed water trade in the second survey, that was held after the establishment of the potato processing factory, consists mainly of the exchange of water without payment between relatives or neighbours, and seems to be meant to improve the timing of water applications to crops with different seasonal water requirements. Those who have started trading water rights tend to have more land with water use rights than other potato farmers. High transaction costs and information asymmetry between the government and water users, however, severely constrain the trading of water use rights in the region. Chapter 6 summarizes and integrates the main findings, discusses the policy implications and the limitations of the research, and presents some suggestions for further research.
显示更多 [+] 显示较少 [-]Qualidade e diversidade microbiana da água obtida pelo sistema de purificação instalado no prédio dos Laboratórios de Qualidade e Segurança de Alimentos | Microbial diversity and quality of water obtained by purification system installed in the building of Quality and Food Safety Laboratories 全文
2013 | 2014
Alves, Roberta Barbosa Teodoro | http://lattes.cnpq.br/8933004880646704 | Fontes, Edimar Aparecida Filomeno | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4792339T8 | Carvalho, Antônio Fernandes de | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781655T2 | Andrade, Nélio José de | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788281Y5 | Bernardes, Patrícia Campos | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4711525D7 | Pires, Ana Clarissa dos Santos | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4776833U9
A água purificada exerce um papel fundamental na rotina laboratorial e em diversas aplicações, exigindo elevado grau de pureza. Deste modo, foi realizada uma avaliação da qualidade da água distribuída pelo sistema de purificação de água instalado nos Laboratórios de Qualidade e Segurança de Alimentos do Departamento de Tecnologia de Alimentos da UFV. A primeira parte do trabalho aborda a qualidade físico-química e microbiológica da água potável que alimenta o sistema de purificação e também a qualidade da água obtida e distribuída nos pontos de uso. A instalação e as condições de operação e desempenho do sistema de purificação de água foram avaliados. A avaliação da água potável que abastece o sistema de purificação permitiu constatar uma boa qualidade, tanto para as especificações físico-químicas (alcalinidade 20,3 mg·L-1 CaCO3, condutividade 62,7 μS·cm-1, cloro residual livre 0,84 mg·L-1, pH 6,17, temperatura 25 °C, índice de saturação de Langelier -3,76, dureza 20 mg·L-1 CaCO3, e sílica 15,2 mg·L- SiO2) quanto microbiológicas (1,24 log10 UFC·mL-1). A água purificada obtida pelo sistema esteve sempre de acordo com as especificações físico-químicas e microbiológicas estabelecidas pelo fabricante do equipamento e pela Farmacopeia Brasileira. A água purificada distribuída foi aprovada nas especificações físico-químicas, porém o nível de contagem de bactérias heterotróficas estava acima do permitido (>2 log10 UFC·mL-1), o que pode comprometer alguns resultados analíticos dos laboratórios. Foi verificado ainda que higienização do reservatório de água potável e do reservatório de água purificada deve ser feita a cada 6 meses, uma vez que os resultados deste procedimento mostraram redução significativa (p<0,05) na contagem de bactérias heterotróficas. Além disso, o sistema deve apresentar manutenção e reposição dos elementos filtrantes e acessórios do equipamento. A segunda parte do estudo teve como objetivo identificar os isolados bacterianos por meio de técnicas moleculares. Com o sequenciamento do gene ribossômico 16S rDNA, as espécies identificadas na água potável foram Aneurinibacillus aneurinilyticus, Enterococcus faecium, Escherichia fergusonii e Enterobacter cloacae subsp. Dissolvens. Na água purificada, foram encontradas as espécies Acinetobacter calcoaceticus e Staphylococcus warneri e na água distribuída, Enterococcus faecium e Enterobacter cloacae subsp. Dissolvens. A superfície dos isolados identificados foi submetidas à medida do ângulo de contato, com intuito de fazer a previsão teórica da adesão em função da hidrofobicidade das superfícies dos micro-organismos e da superfície do Loop de distribuição. As espécies e a superfície estudadas foram consideradas hidrofílicas. A adesão não foi termodinamicamente favorável (ΔG adesão >0) entre a superfície e todas as espécies identificadas. Os resultados de predição termodinâmica foram compatíveis com as contagens de bactérias heterotróficas da superfície de polipropileno (loop de distribuição) que atingiram valores de aproximadamente 5 log10 UFC·cm-2, indicando que não se caracteriza como biofilmes. | Purified water exert a fundamental role in routine clinical practice and in many applications requiring high purity. Thus, an assessment of the quality of the water distributed by water purification system installed in the Laboratory of Quality and Food Safety of the Department of Food Technology at UFV was performed. The first part of the paper deals with physical-chemical and microbiological quality of drinking water that feeds the purification system and the quality of water produced and distributed at points of use. The installation and operating conditions and performance of the water purification system were evaluated. The evaluation of drinking water supply purification system have revealed a good quality for both the physical and chemical specifications (alkalinity 20,3 mg·L-1 CaCO3, conductivity 62,7 μS·cm-1, chlorine 0,84 mg·L-1, pH 6,17, temperature 25 °C, Langelier Saturation Index -3,76, hardness 20 mg·L-1 CaCO3 and silica 15,2 mg·L-1 SiO2) and microbiological (1,24 log10 UFC·mL-1). The purified water produced by the system always in accordance with the specifications established by the equipment manufacturer. Purified water distributed showed the physicochemical requirements within the allowed, but the levels of heterotrophic bacteria counts were higher than allowed (> 2 log10 UFC·mL-1), which may compromise some analytical results performed in laboratories. It was found, although cleaning of drinking water reservoir and the reservoir of purified water should be performed every 6 months, once the results of this procedure showed a significant reduction (p <0.05) in the count of heterotrophic bacteria. In addition, the system shall provide the maintenance and replacement of filter elements and equipment accessories. The second part of the study aimed to identify the bacterial isolates using molecular techniques. With the sequencing of the ribosomal 16S rDNA species identified in drinking water were Aneurinibacillus aneurinilyticus, Enterococcus faecium, Escherichia fergusonii and Enterobacter cloacae subsp. Dissolvens. Purified water the Acinetobacter calcoaceticus species were found; Staphylococcus warneri and distributed water Enterococcus faecium and Enterobacter cloacae subsp. Dissolvens. The surface of the isolates identified were subjected to measurement of contact angle, in order to realize the theoretical prediction of membership depending on the hydrophobicity of the micro-organisms and the surface of the Loop distribution. The species studied were considered and the surface hydrophilic. Adherence was not thermodynamically favorable (ΔG adhesion> 0) between the surface and all identified species. The species studied were considered and the surface hydrophilic. Adherence was not thermodynamically favorable (ΔG membership > 0) between the surface and all identified species. The results of thermodynamic prediction were consistent with heterotrophic bacteria counts the surface of polypropylene (loop distribution) which reached values of approximately 5 log10 CFU· cm-2 indicating that it is characterized as biofilms. | Conselho Nacional de Desenvolvimento Científico e Tecnológico
显示更多 [+] 显示较少 [-]The water for food paradox. [Selected from the World Water Week, Stockholm, Sweden, 26-31 August 2012] 全文
2013
Chartres, Colin J. | Sood, Aditya
This paper considers whether there will be sufficient water available to grow enough food for a predicted global population of 9 billion in 2050, based on three population and GDP growth modelling scenarios. Under the a low population growth with high GDP growth scenario, global consumptive water demand is forecast to increase significantly to over 6,000 km3, which is approximately 3,000 km3 greater that consumptive use in the year 2000. Also of concern is that rising global temperatures are going to increase potential evaporation, and t us irrigation water demand, by up to 17%. Sustainable intensification of agriculture can provide solutions to this predicament. However, productivity growth i not fast enough and we face considerable risks in the next 20 to 30 years. Concerted action to combat food insecurity and water scarcity is required based on agricultural research and development, policy reform and greater water productivity, if the world is to feed its growing population.
显示更多 [+] 显示较少 [-]The water for food paradox. [Selected from the World Water Week, Stockholm, Sweden, 26-31 August 2012]. 全文
2013
Chartres, Colin | Sood, Aditya
This paper considers whether there will be sufficient water available to grow enough food for a predicted global population of 9 billion in 2050, based on three population and GDP growth modelling scenarios. Under the a low population growth with high GDP growth scenario, global consumptive water demand is forecast to increase significantly to over 6,000 km3, which is approximately 3,000 km3 greater that consumptive use in the year 2000. Also of concern is that rising global temperatures are going to increase potential evaporation, and t us irrigation water demand, by up to 17%. Sustainable intensification of agriculture can provide solutions to this predicament. However, productivity growth i not fast enough and we face considerable risks in the next 20 to 30 years. Concerted action to combat food insecurity and water scarcity is required based on agricultural research and development, policy reform and greater water productivity, if the world is to feed its growing population.
显示更多 [+] 显示较少 [-]The water for food paradox. [Selected from the World Water Week, Stockholm, Sweden, 26-31 August 2012] 全文
2013
Chartres, Colin J. | Sood, Aditya
This paper considers whether there will be sufficient water available to grow enough food for a predicted global population of 9 billion in 2050, based on three population and GDP growth modelling scenarios. Under the a low population growth with high GDP growth scenario, global consumptive water demand is forecast to increase significantly to over 6,000 km3, which is approximately 3,000 km3 greater that consumptive use in the year 2000. Also of concern is that rising global temperatures are going to increase potential evaporation, and t us irrigation water demand, by up to 17%. Sustainable intensification of agriculture can provide solutions to this predicament. However, productivity growth i not fast enough and we face considerable risks in the next 20 to 30 years. Concerted action to combat food insecurity and water scarcity is required based on agricultural research and development, policy reform and greater water productivity, if the world is to feed its growing population.
显示更多 [+] 显示较少 [-]Management of water and agroecosystems in landscapes for sustainable food security 全文
2013
Boelee, Eline | Scherr, S. J. | Pert, P. L. | Barron, J. | Finlayson, M. | Descheemaeker, K. | Milder, J. C. | Fleiner, R. | Nguyen-Khoa, S. | Barchiesi, S. | Bunting, S. W. | Tharme, R. E. | Khaka, E. | Coates, D. | Solowey, E. M. | Lloyd, G. J. | Molden, D. | Cook, Simon
Novel water-resistant UV-activated oxygen indicator for intelligent food packaging 全文
2013
Vu, Chau Hai Thai | Won, Keehoon
For the first time, alginate polymer has been applied to prevent dyes from leaching out of colorimetric oxygen indicator films, which enable people to notice the presence of oxygen in the package in an economic and simple manner. The dye-based oxygen indicator film suffers from dye leaching upon contact with water. In this work, UV-activated visual oxygen indicator films were fabricated using thionine, glycerol, P25 TiO2, and zein as a redox dye, a sacrificial electron donor, UV-absorbing semiconducting photocatalyst, and an encapsulation polymer, respectively. When this zein-coated film was immersed in water for 24h, the dye leakage was as high as 80.80±0.45%. However, introduction of alginate (1.25%) as the coating polymer considerably diminished the dye leaching to only 5.80±0.06%. This is because the ion-binding ability of alginate could prevent the cation dye from leaching into water. This novel water-resistant UV-activated oxygen indicator was also successfully photo-bleached and regained colour fast in the presence of oxygen.
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