Kooperativer Bibliotheksverbund

UID:

Format: 1 Online-Ressource (29 p)

Series Statement: World Bank E-Library Archive

Content: Maintaining permanent coverage of the soil using crop residues is an important and commonly recommended practice in conservation agriculture. Measuring this practice is an essential step in improving knowledge about the adoption and impact of conservation agriculture. Different data collection methods can be implemented to capture the field level crop residue coverage for a given plot, each with its own implications for the survey budget, implementation speed, and respondent and interviewer burden. This study tests six alternative methods of crop residue coverage measurement among the same sample of rural households in Ethiopia. The relative accuracy of these methods is compared against a benchmark, the line-transect method. The alternative methods compared against the benchmark include: (i) interviewee (respondent) estimation; (ii) enumerator estimation visiting the field; (iii) interviewee with visual-aid without visiting the field; (iv) enumerator with visual-aid visiting the field; (v) field picture collected with a drone and analyzed with image-processing methods; and (vi) satellite picture of the field analyzed with remote sensing methods. Results of the methodological experiment show that survey-based methods tend to underestimate field residue cover. When quantitative data on cover are needed, the best estimates are provided by visual-aid protocols. For categorical analysis (such as greater than 30 percent cover or not), visual-aid protocols and remote sensing methods perform equally well. Among survey-based methods, the strongest correlates of measurement errors are total farm size, field size, distance, and slope. The results deliver a ranking of measurement options that can inform survey practitioners and researchers

Additional Edition: Erscheint auch als Druck-Ausgabe Kosmowski, Frederic On the Ground or in the Air? A Methodological Experiment on Crop Residue Cover Measurement in Ethiopia Washington, D.C : The World Bank, 2016

Language: English

DOI: 10.1596/1813-9450-7813

URL: Volltext  (URL des Erstveröffentlichers)

URL: Volltext  (Deutschlandweit zugänglich)

UID:

Format: 1 Online-Ressource (27 p)

Series Statement: World Bank E-Library Archive

Content: Sweet potato (Ipomoea batatas) varieties have important nutritional differences and there is strong interest to identify nutritionally superior varieties for dissemination. In agricultural household surveys, this information is often collected based on the farmer's self-report. However, recent evidence has demonstrated the inherent difficulties in correctly identifying varieties from self-report information. This study examines the accuracy of self-report information on varietal identification from a data capture experiment on sweet potato varieties in southern Ethiopia. Three household-based methods of identifying varietal adoption are tested against the benchmark of DNA fingerprinting: (A) elicitation from farmers with basic questions for the most widely planted variety; (B) farmer elicitation on five sweet potato phenotypic attributes by showing a visual-aid protocol; and (C) enumerator recording observations on five sweet potato phenotypic attributes using a visual-aid protocol and visiting the field. The reference being the DNA fingerprinting, about 30 percent of improved varieties were identified as local or non-improved, and 20 percent of farmers identified a variety as local when it was in fact improved. The variety names given by farmers delivered inconsistent and fuzzy varietal identities. The visual-aid protocols employed in methods B and C were better than method A, but still way below the adoption estimates given by the DNA fingerprinting method. The findings suggest that estimating the adoption of improved varieties with methods based on farmer self-reports is questionable, and point toward a wider use of DNA fingerprinting, likely to become the gold standard for crop varietal identification

Additional Edition: Erscheint auch als Druck-Ausgabe Kosmowski, Frederic Varietal Identification in Household Surveys: Results from an Experiment Using DNA Fingerprinting of Sweet Potato Leaves in Southern Ethiopia Washington, D.C : The World Bank, 2016

Language: English

DOI: 10.1596/1813-9450-7812

URL: Volltext  (URL des Erstveröffentlichers)

URL: Volltext  (Deutschlandweit zugänglich)

UID:

Format: 1 Online-Ressource (circa 46 Seiten) , Illustrationen

Series Statement: Working paper / European Bank for Reconstruction and Development no. 287

Language: English

Keywords: Graue Literatur

URL: Deutschlandweit zugänglich

URL: Deutschlandweit zugänglich

UID:

Format: 1 online resource (27 pages)

Series Statement: Policy research working papers.

Content: Sweet potato (Ipomoea batatas) varieties have important nutritional differences and there is strong interest to identify nutritionally superior varieties for dissemination. In agricultural household surveys, this information is often collected based on the farmer's self-report. However, recent evidence has demonstrated the inherent difficulties in correctly identifying varieties from self-report information. This study examines the accuracy of self-report information on varietal identification from a data capture experiment on sweet potato varieties in southern Ethiopia. Three household-based methods of identifying varietal adoption are tested against the benchmark of DNA fingerprinting: (A) elicitation from farmers with basic questions for the most widely planted variety; (B) farmer elicitation on five sweet potato phenotypic attributes by showing a visual-aid protocol; and (C) enumerator recording observations on five sweet potato phenotypic attributes using a visual-aid protocol and visiting the field. The reference being the DNA fingerprinting, about 30 percent of improved varieties were identified as local or non-improved, and 20 percent of farmers identified a variety as local when it was in fact improved. The variety names given by farmers delivered inconsistent and fuzzy varietal identities. The visual-aid protocols employed in methods B and C were better than method A, but still way below the adoption estimates given by the DNA fingerprinting method. The findings suggest that estimating the adoption of improved varieties with methods based on farmer self-reports is questionable, and point toward a wider use of DNA fingerprinting, likely to become the gold standard for crop varietal identification.

Language: English

DOI: 10.1596/1813-9450-7812

UID:

Format: 1 online resource (27 pages)

Series Statement: Policy research working papers.

Content: Sweet potato (Ipomoea batatas) varieties have important nutritional differences and there is strong interest to identify nutritionally superior varieties for dissemination. In agricultural household surveys, this information is often collected based on the farmer's self-report. However, recent evidence has demonstrated the inherent difficulties in correctly identifying varieties from self-report information. This study examines the accuracy of self-report information on varietal identification from a data capture experiment on sweet potato varieties in southern Ethiopia. Three household-based methods of identifying varietal adoption are tested against the benchmark of DNA fingerprinting: (A) elicitation from farmers with basic questions for the most widely planted variety; (B) farmer elicitation on five sweet potato phenotypic attributes by showing a visual-aid protocol; and (C) enumerator recording observations on five sweet potato phenotypic attributes using a visual-aid protocol and visiting the field. The reference being the DNA fingerprinting, about 30 percent of improved varieties were identified as local or non-improved, and 20 percent of farmers identified a variety as local when it was in fact improved. The variety names given by farmers delivered inconsistent and fuzzy varietal identities. The visual-aid protocols employed in methods B and C were better than method A, but still way below the adoption estimates given by the DNA fingerprinting method. The findings suggest that estimating the adoption of improved varieties with methods based on farmer self-reports is questionable, and point toward a wider use of DNA fingerprinting, likely to become the gold standard for crop varietal identification.

Language: English

DOI: 10.1596/1813-9450-7812

UID:

Format: 1 online resource (29 pages)

Series Statement: Policy research working papers.

Content: Maintaining permanent coverage of the soil using crop residues is an important and commonly recommended practice in conservation agriculture. Measuring this practice is an essential step in improving knowledge about the adoption and impact of conservation agriculture. Different data collection methods can be implemented to capture the field level crop residue coverage for a given plot, each with its own implications for the survey budget, implementation speed, and respondent and interviewer burden. This study tests six alternative methods of crop residue coverage measurement among the same sample of rural households in Ethiopia. The relative accuracy of these methods is compared against a benchmark, the line-transect method. The alternative methods compared against the benchmark include: (i) interviewee (respondent) estimation; (ii) enumerator estimation visiting the field; (iii) interviewee with visual-aid without visiting the field; (iv) enumerator with visual-aid visiting the field; (v) field picture collected with a drone and analyzed with image-processing methods; and (vi) satellite picture of the field analyzed with remote sensing methods. Results of the methodological experiment show that survey-based methods tend to underestimate field residue cover. When quantitative data on cover are needed, the best estimates are provided by visual-aid protocols. For categorical analysis (such as greater than 30 percent cover or not), visual-aid protocols and remote sensing methods perform equally well. Among survey-based methods, the strongest correlates of measurement errors are total farm size, field size, distance, and slope. The results deliver a ranking of measurement options that can inform survey practitioners and researchers.

Language: English

DOI: 10.1596/1813-9450-7813

UID:

Format: 1 online resource (29 pages)

Series Statement: Policy research working papers.

Content: Maintaining permanent coverage of the soil using crop residues is an important and commonly recommended practice in conservation agriculture. Measuring this practice is an essential step in improving knowledge about the adoption and impact of conservation agriculture. Different data collection methods can be implemented to capture the field level crop residue coverage for a given plot, each with its own implications for the survey budget, implementation speed, and respondent and interviewer burden. This study tests six alternative methods of crop residue coverage measurement among the same sample of rural households in Ethiopia. The relative accuracy of these methods is compared against a benchmark, the line-transect method. The alternative methods compared against the benchmark include: (i) interviewee (respondent) estimation; (ii) enumerator estimation visiting the field; (iii) interviewee with visual-aid without visiting the field; (iv) enumerator with visual-aid visiting the field; (v) field picture collected with a drone and analyzed with image-processing methods; and (vi) satellite picture of the field analyzed with remote sensing methods. Results of the methodological experiment show that survey-based methods tend to underestimate field residue cover. When quantitative data on cover are needed, the best estimates are provided by visual-aid protocols. For categorical analysis (such as greater than 30 percent cover or not), visual-aid protocols and remote sensing methods perform equally well. Among survey-based methods, the strongest correlates of measurement errors are total farm size, field size, distance, and slope. The results deliver a ranking of measurement options that can inform survey practitioners and researchers.

Language: English

DOI: 10.1596/1813-9450-7813

UID:

Format: 1 online resource (463 p.)

ISBN: 2-7099-2147-2

Content: L’avenir de l'Afrique de l'Ouest dépend de la capacité de son agriculture à assurer la sécurité alimentaire de sa population, qui devrait doubler en vingt ans, tout en faisant face aux risques nouveaux engendrés par le réchauffement climatique. En effet, les modifications de température et de précipitations déjà à l’oeuvre, et qui devraient s’amplifier, auront dans un futur proche des répercussions importantes sur la production agricole et sur les ressources en eau de cette partie du continent africain. L’adaptation des sociétés rurales aux risques climatiques est une des clés pour relever ce nouveau défi. Pour mieux en connaître le potentiel, les processus et les barrières, cet ouvrage analyse les évolutions récentes et en cours du climat et de l’environnement, et étudie comment les sociétés rurales les perçoivent et les intègrent : quels sont les impacts de ces changements, quelles vulnérabilités mais aussi quelles nouvelles opportunités entraînent-ils ? Comment les populations s’y adaptent-elles, et quelles innovations mettent-elles en oeuvre, alors que les effets induits par le climat interagissent avec les changements sociaux, politiques, économiques et techniques en cours sur le continent ? En associant des chercheurs français et africains (climatologues, agronomes, hydrologues, écologues, démographes, géographes, anthropologues, sociologues…) dans une approche interdisciplinaire, cet ouvrage apporte une contribution précieuse pour mieux anticiper les risques climatiques et évaluer les capacités des sociétés africaines à y faire face.

Note: Évolutions récentes et futures du climat en Afrique de l'Ouest. Évidences, incertitudes et perceptions. , Introduction / , Le réchauffement climatique observé depuis 1950 au Sahel / , Le retour d'une période humide au Sahel? Observations et perspectives / , Les projections du climat en Afrique de l'Ouest. Évidences et incertitudes / , Observations et perceptions des changements climatiques. Analyse comparée dans trois pays d'Afrique de l'Ouest / , Quand la nature nous parle. Une analyse comparée des représentations des changements climatiques et environnementaux / , Impacts du climat et transformations environnementales. , Entre désertification et reverdissement du Sahel. Que se passe-t-il vraiment? / , Facteurs anthropiques et environnementaux de la recrudescence des inondations au Sahel / , La contrainte fourragère des élevages pastoraux et agropastoraux du Sahel. Adaptations et perspectives / , Évolutions paradoxales des pares en Sahel non cultivé. Diagnostic, causes et conséquences / , Les impacts du changement climatique sur les rendements agricoles en Afrique de l'Ouest / , Transformations sociétales des populations rurales. , Introduction / , Populations rurales face aux aléas environnementaux. Expériences africaines / , Droits au sol et gestion de la fertilité. Deux perspectives différentes: Djougou (Bénin) et Niakhar (Sénégal) / , Rôle des migrations saisonnières et pluriannuelles dans la réduction de la vulnérabilité. Les communes de Hombori et Djougou / , Migrations saisonnières et changement climatique en milieu rural sénégalais. Forme ou échec de l'adaptation? / , La migration féminine, une stratégie extra-agricole d'adaptation aux changements climatiques et environnementaux dans l'Imanan (Niger) / , Changements politiques, dynamiques foncières et recompositions socio-économiques. La commune de l'Imanan (Niger) / , Adaptation des systèmes de production et innovations. , Introduction / , Innover en milieu rural ouest-africain. Quels changements dans les pratiques agricoles des exploitants? / , Le retour du mil sanio dans le Sine. Une adaptation raisonnée à l'évolution climatique / , Réintroduire l'élevage pour accroître la durabilité des terroirs villageois d'Afrique de l'Ouest. Le cas du bassin arachidier au Sénégal / , Un exemple de stratégie adaptée à l'insécurité alimentaire. La culture de la pomme de terre dans l'Imanan (Niger) / , Conclusion / , French

Additional Edition: ISBN 2-7099-2146-4

Language: French

DOI: 10.4000/books.irdeditions.8914

UID:

Format: 1 online resource (432 p.)

ISBN: 2-7099-2425-0

Series Statement: Synthèses

Content: The future of West Africa depends on the capacity of its agriculture to ensure the food security of the population, which should double in the next 20 years, while facing up to the new risks resulting from climate warming. Indeed, the changes in temperature and precipitations already operating and that should become more marked will have serious effects on agricultural production and water resources in this part of Africa in the near future. One of the keys to meeting this new challenge is the adaptation of rural societies to climate risks. To gain better knowledge of the potential, processes and barriers, this book analyses recent and ongoing trends in the climate and the environment and examines how rural societies perceive and integrate them: what are the impacts of these changes, what vulnerabilities are there but also what new opportunities do they bring? How do the populations adapt and what innovations do they implement—while the climate-induced effects interact with the social, political, economic and technical changes that are in motion in Africa? By associating French and African scientists (climatologists, agronomists, hydrologists, ecologists, demographers, geographers, anthropologists, sociologists and others) in a multidisciplinary approach, the book makes a valuable contribution to better anticipation of climatic risks and the evaluation of African societies to stand up to them.

Note: English

Additional Edition: ISBN 2-7099-2424-2

Language: English

DOI: 10.4000/books.irdeditions.12298

UID:

Format: 1 online resource (463 p.)

ISBN: 2-7099-2147-2

Content: L’avenir de l'Afrique de l'Ouest dépend de la capacité de son agriculture à assurer la sécurité alimentaire de sa population, qui devrait doubler en vingt ans, tout en faisant face aux risques nouveaux engendrés par le réchauffement climatique. En effet, les modifications de température et de précipitations déjà à l’oeuvre, et qui devraient s’amplifier, auront dans un futur proche des répercussions importantes sur la production agricole et sur les ressources en eau de cette partie du continent africain. L’adaptation des sociétés rurales aux risques climatiques est une des clés pour relever ce nouveau défi. Pour mieux en connaître le potentiel, les processus et les barrières, cet ouvrage analyse les évolutions récentes et en cours du climat et de l’environnement, et étudie comment les sociétés rurales les perçoivent et les intègrent : quels sont les impacts de ces changements, quelles vulnérabilités mais aussi quelles nouvelles opportunités entraînent-ils ? Comment les populations s’y adaptent-elles, et quelles innovations mettent-elles en oeuvre, alors que les effets induits par le climat interagissent avec les changements sociaux, politiques, économiques et techniques en cours sur le continent ? En associant des chercheurs français et africains (climatologues, agronomes, hydrologues, écologues, démographes, géographes, anthropologues, sociologues…) dans une approche interdisciplinaire, cet ouvrage apporte une contribution précieuse pour mieux anticiper les risques climatiques et évaluer les capacités des sociétés africaines à y faire face.

Note: Évolutions récentes et futures du climat en Afrique de l'Ouest. Évidences, incertitudes et perceptions. , Introduction / , Le réchauffement climatique observé depuis 1950 au Sahel / , Le retour d'une période humide au Sahel? Observations et perspectives / , Les projections du climat en Afrique de l'Ouest. Évidences et incertitudes / , Observations et perceptions des changements climatiques. Analyse comparée dans trois pays d'Afrique de l'Ouest / , Quand la nature nous parle. Une analyse comparée des représentations des changements climatiques et environnementaux / , Impacts du climat et transformations environnementales. , Entre désertification et reverdissement du Sahel. Que se passe-t-il vraiment? / , Facteurs anthropiques et environnementaux de la recrudescence des inondations au Sahel / , La contrainte fourragère des élevages pastoraux et agropastoraux du Sahel. Adaptations et perspectives / , Évolutions paradoxales des pares en Sahel non cultivé. Diagnostic, causes et conséquences / , Les impacts du changement climatique sur les rendements agricoles en Afrique de l'Ouest / , Transformations sociétales des populations rurales. , Introduction / , Populations rurales face aux aléas environnementaux. Expériences africaines / , Droits au sol et gestion de la fertilité. Deux perspectives différentes: Djougou (Bénin) et Niakhar (Sénégal) / , Rôle des migrations saisonnières et pluriannuelles dans la réduction de la vulnérabilité. Les communes de Hombori et Djougou / , Migrations saisonnières et changement climatique en milieu rural sénégalais. Forme ou échec de l'adaptation? / , La migration féminine, une stratégie extra-agricole d'adaptation aux changements climatiques et environnementaux dans l'Imanan (Niger) / , Changements politiques, dynamiques foncières et recompositions socio-économiques. La commune de l'Imanan (Niger) / , Adaptation des systèmes de production et innovations. , Introduction / , Innover en milieu rural ouest-africain. Quels changements dans les pratiques agricoles des exploitants? / , Le retour du mil sanio dans le Sine. Une adaptation raisonnée à l'évolution climatique / , Réintroduire l'élevage pour accroître la durabilité des terroirs villageois d'Afrique de l'Ouest. Le cas du bassin arachidier au Sénégal / , Un exemple de stratégie adaptée à l'insécurité alimentaire. La culture de la pomme de terre dans l'Imanan (Niger) / , Conclusion / , French

Additional Edition: ISBN 2-7099-2146-4

Language: French

DOI: 10.4000/books.irdeditions.8914