The Experts below are selected from a list of 32169 Experts worldwide ranked by ideXlab platform
Ian Scoones - One of the best experts on this subject based on the ideXlab platform.
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perspectives on soil Fertility Change a case study from southern ethiopia
Land Degradation & Development, 1999Co-Authors: Eyasu Elias, Ian ScoonesAbstract:This paper explores the complexities underlying the apparently simple question—Is soil Fertility declining?—for Wolayta in southern Ethiopia, an area famed for its high population densities and extreme pressure on resources. Drawing on extensive field research in the area, the paper examines differing perceptions of soil Fertility decline, and attempts to pick apart the range of evidence of Changes in soil Fertility over time from a variety of different sources, ranging from historical interviews with farmers to fertilizer trials carried out over many years. In contrast to the definitive statements so often made in development policy statements, the actual situation is much less clear. A detailed understanding of soil Fertility dynamics is only reached by a farm and field level examination of soil nutrient balances. Differences according to agroecological zone and socio-economic group are evaluated. These results show that soil Fertility is indeed declining in some places, for some people and over certain periods, but it is not universal. Indeed, soil Fertility is apparently increasing at certain sites. The implications of such findings for development policy and practice are briefly explored. Copyright © 1999 John Wiley & Sons, Ltd.
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The Dynamics of Soil Fertility Change: historical perspectives on environmental transformation from Zimbabwe
The Geographical Journal, 1997Co-Authors: Ian ScoonesAbstract:Soil Fertility is currently highlighted as a major issue for African agricultural development. But embedded within policy statements are a series of underlying assumptions and methodological commitments. This paper questions these, arguing that an historical approach to understanding the dynamics of soil Fertility Change offers important insights of relevance to development policy and planning. Work on environmental Change in southern Zimbabwe emphasizes how issues of non-linear dynamics, spatial heterogeneity and the role of contingent events in precipitating Change are important in understanding the nature of soils and their management. Transformation of soils is seen to be the result of a complex interaction of factors, mediated by a variety of social, economic and political institutions over time. Such insights suggest a more embedded, context-specific, adaptive and learning approach to intervention, which rejects simplistic, aggregated assessments of people-resource relationships, but instead takes uncertainty, complexity and the potential for non-linear Change seriously.
Motuma Tolera - One of the best experts on this subject based on the ideXlab platform.
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comparing farmers perception of soil Fertility Change with soil properties and crop performance in beseku ethiopia
Land Degradation & Development, 2013Co-Authors: Erik Karltun, Mulugeta Lemenih, Motuma ToleraAbstract:Farmers' perceptions of soil Fertility Change were compared with observations on soil quality Changes and crop performance in soils from a chronosequence representing a range of soil ages since conversion from forest to cropland (0 to 57 years). A majority of the farmers, 92 per cent, had observed a decline in soil Fertility on their land. Farmers use crop yield, indicator plants, soil softness and soil colour to judge soil Fertility. They identified 11 plants that they used to indicate high soil Fertility and four plants that they used to indicate low soil Fertility. There was a strong correlation (r = 0·96) between soil organic matter content (loss on ignition) and farmers' ranking of soil Fertility based on colour and softness of soil samples from the chronosequence. The biotest experiment with maize showed an exponential decline in biomass production along the chronosequence, confirming the results of farmers' soil Fertility ranking. In the biotest, total soil N predicted produced biomass well (r2 = 0·95), whereas the relationship with soil available P (Olsen) was less obvious. Among the eight analysed plant nutrients in the maize leaves, N content was found to correlate best with biomass production (r2 = 0·94). We conclude (i) that there is good agreement between farmers' knowledge and scientific indicators of soil Fertility and (ii) that the major reason for declining soil Fertility in Beseku is the decrease in N mineralization over time. Interventions should focus on supporting farmers to implement a diversified nutrient management strategy that can maintain or increase long-term productivity of the soil. Copyright © 2011 John Wiley & Sons, Ltd.
Alaka Malwade Basu - One of the best experts on this subject based on the ideXlab platform.
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girls schooling women s autonomy and Fertility Change in south asia
Population and Development Review, 1997Co-Authors: Roger Jeffery, Alaka Malwade BasuAbstract:This...volume challenges the popular notions that there is a universal and causal relationship between rising levels of schooling and declining levels of Fertility and that schooling enhances female autonomy. Presenting primary evidence from India Pakistan Sri Lanka and Bangladesh and utilising existing census and survey data the eleven original papers in this book explore the interrelated issues of womens autonomy girls schooling and Fertility reduction in South Asia. The volume concludes that schooling is indeed important for women and should definitely be supported and encouraged but not because of the possible impact it may have on Fertility decline. Further that while resources should continue to be devoted to the spread of education this should not be at the expense of providing women-friendly contraceptive and maternal/child health services which give couples the ability to successfully plan the size of the family they want. (EXCERPT)
Erik Karltun - One of the best experts on this subject based on the ideXlab platform.
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comparing farmers perception of soil Fertility Change with soil properties and crop performance in beseku ethiopia
Land Degradation & Development, 2013Co-Authors: Erik Karltun, Mulugeta Lemenih, Motuma ToleraAbstract:Farmers' perceptions of soil Fertility Change were compared with observations on soil quality Changes and crop performance in soils from a chronosequence representing a range of soil ages since conversion from forest to cropland (0 to 57 years). A majority of the farmers, 92 per cent, had observed a decline in soil Fertility on their land. Farmers use crop yield, indicator plants, soil softness and soil colour to judge soil Fertility. They identified 11 plants that they used to indicate high soil Fertility and four plants that they used to indicate low soil Fertility. There was a strong correlation (r = 0·96) between soil organic matter content (loss on ignition) and farmers' ranking of soil Fertility based on colour and softness of soil samples from the chronosequence. The biotest experiment with maize showed an exponential decline in biomass production along the chronosequence, confirming the results of farmers' soil Fertility ranking. In the biotest, total soil N predicted produced biomass well (r2 = 0·95), whereas the relationship with soil available P (Olsen) was less obvious. Among the eight analysed plant nutrients in the maize leaves, N content was found to correlate best with biomass production (r2 = 0·94). We conclude (i) that there is good agreement between farmers' knowledge and scientific indicators of soil Fertility and (ii) that the major reason for declining soil Fertility in Beseku is the decrease in N mineralization over time. Interventions should focus on supporting farmers to implement a diversified nutrient management strategy that can maintain or increase long-term productivity of the soil. Copyright © 2011 John Wiley & Sons, Ltd.
Roger Jeffery - One of the best experts on this subject based on the ideXlab platform.
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girls schooling women s autonomy and Fertility Change in south asia
Population and Development Review, 1997Co-Authors: Roger Jeffery, Alaka Malwade BasuAbstract:This...volume challenges the popular notions that there is a universal and causal relationship between rising levels of schooling and declining levels of Fertility and that schooling enhances female autonomy. Presenting primary evidence from India Pakistan Sri Lanka and Bangladesh and utilising existing census and survey data the eleven original papers in this book explore the interrelated issues of womens autonomy girls schooling and Fertility reduction in South Asia. The volume concludes that schooling is indeed important for women and should definitely be supported and encouraged but not because of the possible impact it may have on Fertility decline. Further that while resources should continue to be devoted to the spread of education this should not be at the expense of providing women-friendly contraceptive and maternal/child health services which give couples the ability to successfully plan the size of the family they want. (EXCERPT)