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No Thumbnail AvailableProjectProgramme / project reportPreliminary studies on the effects of fresh and fermented pig manure on fish production
Network of Aquaculture Centres in Asia
1988Also available in:
No results found.The growth of several cultivated fishes of Cyprinidae was studied using cognate fresh and fermented pig manure and the equivalent fertilizers N and P as sole inputs to different experimental groups of fish ponds. Experiment I was conducted from June to October 1986, experiment II from March to October 1987. The proportions of fish production from chemical-fertilized ponds (C), fermented pig manured ponds (F1), and fresh pig manured ponds (F2) were 100:156:226 and 100:294:382 respectively. The ratio of fish production of F1 ponds to F2 ponds was 100 to 145 in experiment I and 100 to 130 in experiment II, respectively.The chlorophyl content, zooplankton biomass, bacterial activity and BOD were lower in the C ponds than in the F1 and F2 ponds, while the DO concentration was higher. There was little difference in the concentration of NH4-N and PO4-P among the experimental ponds. The physico-chemical parameters in the F1 and F2 ponds were not always in conformity with the fish production. Some parameters were contradictory in these two experiments. In the experiment I, the content of NH4-N in the F1 ponds was lower than that in the F2 ponds, and the content of chlorophyl and the biomass of zooplankton in the F1 ponds were greater than those in the F2 ponds. In contrast, in experiment II all these three parameters were reversed in the F1 and F2 ponds. These results indicate that part of the fish production in the C ponds came from the natural planktonic food chain, while in the F1 and F2 ponds, much of the production was derived from the manure detritus as well as from the planktonic food chain. The nutrient value of fermented pig manure is probably less than that of fresh manure because of bacterial decomposition during fermentation. There is a complicated relationship among various physico-chemical factors after manure application in the F1 and F2 ponds. -
No Thumbnail AvailableProjectProgramme / project reportComparative study on the effects of fresh and fermented pig manure on fish yield
Establishment of a Network of Aquaculture Centres in Asia
1986Also available in:
No results found.1) Pig excreta after biogas fermentation are used as a manure source in fish ponds. Not only partial energy can be obtained, but also the decomposition of pig excreta can be conducted fully in anaerabic conditions, and the quick effective nutritional constituents would be raised and preserved. As a result, the biological resources can be reasonably utilized. 2) After applying fermented manure in fish ponds, the content of effective nutritional constituents augmented, resulting in the prolifera tion and growth of plankton and the improvement of the composition of phytoplankton. Fermented manure decreased the D.O. consumption during the process of decomposition of organic matter, and thus, it improved the ecological environment for various species of fish; it raised the food utilization rate with the result that fish yield could be increased. 3) Based on the comparative study for 2 years, the fish yield by using fermented manure was 7.1–25.6% higher than that by using fresh pig manure . The increment of feed-eaters is greater than the increment of plankton-feeders. At the same time, the quality of fish has been improved. It's worth extending the techniques owing to apparent economic benefit. 4) The synchroneous development of livestock-poultry culture, biogas utilization and fresh water aquaculture should be positively encouraged. It could lead to multi-storied comprehensive utilization of biological resources so as to raise the value of biological resources. -
No Thumbnail AvailableProjectProgramme / project reportPreliminary studies on the effects of three animal manures on the ecological conditions of pond water and fish growth
Establishment of a Network of Aquaculture Centres in Asia
1983Also available in:
No results found.The use of organic manure in aquaculture is one of the main inputs in the Chinese system of integrated fish farming. Although many scientists in China and elsewhere have done much work on the effects of animal manure on aquaculture production (Chen Qiyu et al, 1982, Buck, 1978. 1979; Schroeder 1978, 1980; McGeacin et al, 1982; Stickney, 1977; Jhingran et al, 1980; Edwards, 1980; Zweig, 1981), little is known of the series of physical, chemical and biological processes which are taking place in a pond after application of manure. The complexity of energy recycling needs further studies. The aim of this study is to determine the independent contribution of three animal manures to changes in the ecological condition of pond water and fish production. The results to be obtained may provide the scientific basis for further research on the use of organic manure in fish culture.
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BookletHigh-profileFAO Strategy on Climate Change 2022–2031 2022The FAO Strategy on Climate Change 2022–2031 was endorsed by FAO Council in June 2022. This new strategy replaces the previous strategy from 2017 to better FAO's climate action with the Strategic Framework 2022-2031, and other FAO strategies that have been developed since then. The Strategy was elaborated following an inclusive process of consultation with FAO Members, FAO staff from headquarters and decentralized offices, as well as external partners. It articulates FAO's vision for agrifood systems by 2050, around three main pillars of action: at global and regional level, at country level, and at local level. The Strategy also encourages key guiding principles for action, such as science and innovation, inclusiveness, partnerships, and access to finance.
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Book (stand-alone)Technical bookThe future of food and agriculture - Trends and challenges 2017
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No results found.What will be needed to realize the vision of a world free from hunger and malnutrition? After shedding light on the nature of the challenges that agriculture and food systems are facing now and throughout the 21st century, the study provides insights into what is at stake and what needs to be done. “Business as usual” is not an option. Major transformations in agricultural systems, rural economies, and natural resources management are necessary. The present study was undertaken for the quadrennial review of FAO’s strategic framework and for the preparation of the Organization Medium-Term plan 2018-2021. -
BookletCorporate general interestEmissions due to agriculture
Global, regional and country trends 2000–2018
2021Also available in:
No results found.The FAOSTAT emissions database is composed of several data domains covering the categories of the IPCC Agriculture, Forestry and Other Land Use (AFOLU) sector of the national GHG inventory. Energy use in agriculture is additionally included as relevant to emissions from agriculture as an economic production sector under the ISIC A statistical classification, though recognizing that, in terms of IPCC, they are instead part of the Energy sector of the national GHG inventory. FAO emissions estimates are available over the period 1961–2018 for agriculture production processes from crop and livestock activities. Land use emissions and removals are generally available only for the period 1990–2019. This analytical brief focuses on overall trends over the period 2000–2018.