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Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins النص الكامل
2011
Xueliang Cai | D. Molden | Mohammed Mainuddin | Bharat Sharma | Mobin-ud-Din Ahmad | Poolad Karimi
Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins النص الكامل
2011
Xueliang Cai | D. Molden | Mohammed Mainuddin | Bharat Sharma | Mobin-ud-Din Ahmad | Poolad Karimi
This article summarizes the results of water productivity assessment in 10 river basins across Asia, Africa and South America, representing a range of agro-climatic and socio-economic conditions. Intensive farming in the Asian basins gives much greater agricultural outputs and higher water productivity. Largely subsistence agriculture in Africa has significantly lower water productivity. There is very high intra-basin variability, which is attributed mainly to lack of inputs, and poor water and crop management. Closing gaps between “bright spots” and the poorly performing areas are the major tasks for better food security and improved livelihoods, which have to be balanced with environmental sustainability.
اظهر المزيد [+] اقل [-]Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins النص الكامل
2011
Xueliang Cai | David, S. | Mainuddin, M. | Sharma, Bharat R. | Ahmad, Mobin-ud-Din | Karimi, Poolad
This article summarizes the results of water productivity assessment in 10 river basins across Asia, Africa and South America, representing a range of agro-climatic and socio-economic conditions. Intensive farming in the Asian basins gives much greater agricultural outputs and higher water productivity. Largely subsistence agriculture in Africa has significantly lower water productivity. There is very high intra-basin variability, which is attributed mainly to lack of inputs, and poor water and crop management. Closing gaps between "bright spots? and the poorly performing areas are the major tasks for better food security and improved livelihoods, which have to be balanced with environmental sustainability.
اظهر المزيد [+] اقل [-]Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins النص الكامل
2011
Cai X | Molden, David J. | Mainuddin, M. | Sharma, B. | Ahmad, M.D. | Karimi, P.
Conventional wisdom says that the world is heading for a major water crisis. By 2050, global population will increase from 7 billion to a staggering 9.5 billion and the demands this will place on food and water systems will inevitably push river basins over the edge. The findings from this book present a different picture. While it is convenient to visualize an inevitable global water and food crisis in which increasing demands result in increasing poverty, food insecurity and conflict, the reality is far more nuanced and revolves around the politics of equitable and sustainable development of resources. The first part of this book provides detailed insight into conditions of water flows within nine river basins. In the second part, authors summarize and re-analyze the outcome of the nine basins, providing a coherent global picture of water, water productivity and development. They assess the impacts of variations of these attributes on development and approaches for poverty alleviation, and explore the institutional factors that support or obstruct change. How people will manage river systems while protecting vital ecosystem functions will make the difference between catastrophe and survival. As Prof Asit Biswas points out, "… the world is facing a water crisis not because of physical scarcity of water but because of poor management practices in nearly all countries of the world." The book is based on the four years (2006-2010) of extensive research into the state of ten of the world’s major river basins carried out under the CGIAR Challenge Program for Water and Food’s Basin Focal Project.
اظهر المزيد [+] اقل [-]Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins النص الكامل
2011
Cai, Xueliang | Molden, David | Mainuddin, Mohammed | Sharma, Bharat | Ahmad, Mobin-ud-Din | Karimi, Poolad
This article summarizes the results of water productivity assessment in 10 river basins across Asia, Africa and South America, representing a range of agro-climatic and socio-economic conditions. Intensive farming in the Asian basins gives much greater agricultural outputs and higher water productivity. Largely subsistence agriculture in Africa has significantly lower water productivity. There is very high intra-basin variability, which is attributed mainly to lack of inputs, and poor water and crop management. Closing gaps between “bright spots” and the poorly performing areas are the major tasks for better food security and improved livelihoods, which have to be balanced with environmental sustainability.
اظهر المزيد [+] اقل [-]Water quality and Nile tilapia growth performance under different feeding schedules=Qualidade de água e desempenho produtivo da tilápia do Nilo submetida a diferentes programas alimentares النص الكامل
2011
Marcelo Vinícius do Carmo e Sá | Rafael Barroso Martins | Davi de Holanda Cavalcante | Vanessa Tomaz Rebouças | Nayara Nunes Caldini
The present study investigated the effects of different feeding schedules on certain variables of water quality and growth performance of Nile tilapia juveniles. Fifteen 25-L aquaria were used to hold the experimental fish population for six weeks. Five fingerlings (1.86 0.13 g) were stocked in each aquarium (200 fish m-3; n = 5). The diet provided to fish and the feeding rates adopted were the same for all fish. The daily ration was divided in four meals (8, 11, 13 and 16h). In the positive control group (25/25/25/25), the daily ration was equally divided in the four meals; in the negative control group (40/30/20/10), the daily ration was unevenly divided in a progressively decreasing fashion (40, 30, 20 and 10%) throughout the day; in the experimental group (10/20/30/40), the daily ration was unevenly divided in a progressively increasing fashion (10, 20, 30 and 40%) throughout the day. The feed conversion ratio results were better for 10/20/30/40 than for the other groups. The 10/20/30/40 feeding schedule probably best combined the dietary allowance for fish with the increase in water temperature during the day.<br><br>O presente trabalho investigou os efeitos de diferentes programas alimentares sobre algumas variáveis de qualidade de água e de desempenho zootécnico da tilápia do Nilo. Foram utilizados 15 aquários de 25 L para manter a população experimental por seis semanas. Foram estocados cinco alevinos (1,86 0,13 g) em cada aquário (200 peixes m-3; n = 5). A dieta fornecida aos peixes e as taxas de arraçoamento adotadas foram as mesmas para todos os peixes. A ração diária foi dividida em quatro refeições (8, 11, 13 e 16h). No controle-positivo (25/25/25/25), a ração diária foi igualmente dividida nas quatro refeições; no controle-negativo (40/30/20/10), a ração diária foi desigualmente dividida de modo progressivamente decrescente (40, 30, 20 e 10%) ao longo do dia; no grupo experimental (10/20/30/40), a ração diária foi desigualmente dividida de modo progressivamente crescente (10, 20, 30 e 40%) ao longo do dia. Os resultados do fator de conversão alimentar foram melhores para 10/20/30/40 que para os outros grupos. O programa alimentar 10/20/30/40 foi aquele que provavelmente melhor combinou a oferta de dieta aos peixes cultivados com o aumento na temperatura da água durante o dia.
اظهر المزيد [+] اقل [-]The Challenge Program on Water and Food: Volta Basin Development Challenge inception workshop
2011
CGIAR Challenge Program on Water and Food
The current phase (2010-2013) of the Challenge Program on Water and Food (CPWF) research is addressing the Volta Basin Development Challenge (VBDC) which has been defined as “integrated management of rainwater and small reservoirs for multiple purposes”. The research-for-development program is designed to explore the institutional, socio-economic and technical aspects of small reservoir development and maintenance within a wider rainwater management system in the Volta Basin to maximize water for food and ecosystem services. The purpose of the inception workshop was to review and assess all VBDC projects for coherence and integration towards achieving the overall goal. Secondly it provided an opportunity to launch the research agenda, share our plans and approaches with a wider, relevant stakeholder group, and to obtain important feedback which can be fed into the research process. The key question to address during the workshop was: “what are the lessons learned in the inception phase of VBDC research and how would these lessons shape project implementation in the next phase?”. It was expected that the workshop would contribute to ensuring relevance of the research agenda, as well as strengthening the integration of the five VBDC projects and their teams.
اظهر المزيد [+] اقل [-]Optimal allocation of water for enhanced food production in a mid-Himalayan watershed
2011
Dogra, Pradeep | Sharda, V.N. | Ojasvi, P.R. | Prasher, Shiv O. | Patel, R.M.
Optimal allocation of available water in a middle Himalayan watershed by a linear programming model for maximizing production from crops and livestock, after meeting the present and future demands of human and environmental flows, was analyzed. Present and future water availability under different environmental scenarios at various locations in the watershed was considered. Rice Equivalent Production from the watershed was found to improve by 207% (to 919 tonnes) and Rice Equivalent Yield by 58% (to 4427 kg ha⁻¹) through optimal allocation of available water resource. Occurrence of drought of 60% intensity would limit production to 737 tonnes. Environmental degradation by 2025 would though reduce production marginally, the surplus water available within the watershed would, however, decrease significantly during January to March. Future competition for water would adversely affect economy of the watershed and the region. The government should, therefore, undertake water resource development programmes after making a proper inventory of available resources at watershed level by analyzing the current and future supply and demand scenarios.
اظهر المزيد [+] اقل [-]The state of the world's land and water resources for food and agriculture
2011
The State of the World's Land and Water Resources for Food and Agriculture is FAO's first flagship publication on the global status of land and water resources. It is an 'advocacy' report, to be published every three to five years, and targeted at senior level decision makers in agriculture as well as in other sectors. SOLAW is aimed at sensitizing its target audience on the status of land resources at global and regional levels and FAO's viewpoint on appropriate recommendations for policy formulation. SOLAW focuses on these key dimensions of analysis: (i) quantity, quality of land and water resources, (ii) the rate of use and sustainable management of these resources in the context of relevant socio-economic driving factors and concerns, including food security and poverty, and climate change. This is the first time that a global, baseline status report on land and water resources has been made. It is based on several global spatial databases (e.g. land suitability for agriculture, land use and management, land and water degradation and depletion) for which FAO is the world-recognized data source. Topical and emerging issues on land and water are dealt with in an integrated rather than sectoral manner. The implications of the status and trends are used to advocate remedial interventions which are tailored to major farming systems within different geographic regions.
اظهر المزيد [+] اقل [-]Water moss as a food item of the zoobenthos in the Yenisei River النص الكامل
2011
Kalachova, Galina | Gladyshev, Michail | Sushchik, Nadezhda | Makhutova, Olesia
Water moss as a food item of the zoobenthos in the Yenisei River النص الكامل
2011
Kalachova, Galina | Gladyshev, Michail | Sushchik, Nadezhda | Makhutova, Olesia
Bryophytes are abundant in streams and are a habitat for many invertebrates, but their contribution to the diet of fluvial zoobenthos is still debated. To estimate the amount of bryophyte-derived organic matter assimilated by benthic invertebrates, we used a combination of fatty acid and stable isotope analyses during a four-year monthly study of a littoral site in the Yenisei River (Siberia, Russia). Acetylenic acids, which are highly specific biomarkers of the water moss Fontinalis antipyretica, were found in lipids of all dominant benthic animals: gammarids, ephemeropterans, chironomids and trichopterans. The dominant zoobenthic species, Eulimnogammarus viridis, had maximum levels of the biomarkers in its biomass during winter, and minimum levels in summer. The zoobenthos in the studied site regularly consume and assimilate bryophyte-derived organic matter as a minor supplemental food. This consumption increases in winter, when the main food source of the zoobenthos, epilithic biofilms, are probably scarce.
اظهر المزيد [+] اقل [-]Water moss as a food item of the zoobenthos in the Yenisei River النص الكامل
2011
Kalachova Galina | Gladyshev Michail | Sushchik Nadezhda | Makhutova Olesia
Variance of bioimpedance analysis measurements with physicalactivity and ingestion of food and water النص الكامل
2011
Garçês, M. | Morais, C. | Ribeiro, G. | Pereira, J. | Garcia, M. | Rowcliffe, P. | Taboada, S. | Santos, A. | Correia, Flora | Oliveira, Bruno | Faculdade de Ciências da Nutrição e Alimentação
[resumo] | [abstract]
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