287 research outputs found
StratĂ©gies dâexploitation du fourrage par les Ă©leveurs de la zone sahĂ©lienne du Burkina Faso
Les caractĂ©ristiques de la collecte et de la conservation du fourrage ont Ă©tĂ© Ă©tudiĂ©es dans cinq villages du Sahel. Lâobjectif visĂ© Ă©tait dâidentifier les principales stratĂ©gies utilisĂ©es par les paysans pour minimiser les problĂšmes de disponibilitĂ©s alimentaires du fourrage en saison sĂšche. Des enquĂȘtes Ă passage unique ont Ă©tĂ© ainsi conduites dans 205 exploitations dâagro pasteurs. Les rĂ©sultats de lâĂ©tude rĂ©vĂšlent que lâactivitĂ© deproduction et de conservation du fourrage est largement pratiquĂ©e par les agropasteurs (plus de 88,2%). La collecte concerne aussi bien les fourrages naturels que les rĂ©sidus de rĂ©coltes. Les quantitĂ©s totales de matiĂšres sĂšches stockĂ©es annuellement par exploitant sont de lâordre de 2,043 tonnes, soit respectivement 13,5% et 85,4% sous forme de fourrages naturels et de rĂ©sidus de rĂ©coltes. Sur la base des ressources productives (nombre dâanimaux) quatre classes de paysans ont Ă©tĂ© distinguĂ©es. En saison sĂšche, ces classes dĂ©ploient des stratĂ©gies diffĂ©rentes en matiĂšre de gestion des stocks alimentaires. Les producteurs les moins nantis en ressources animales ont tendance Ă ĂȘtre des vendeurs nets de fourrages tandis que les plus nantis des acheteurs. Les principales contraintes aux activitĂ©s dâexploitation du fourrage naturel sont surtout dâordre Ă©conomique mais aussi de gestion de lâespace
Assessing the biophysical impact and financial viability of soil management technologies under variable climate in Cabo Verde drylands: the PESERA-DESMICE approach
Field trials have demonstrated the potential of soil conservation technologies but have also shown significant spatial-temporal yield variability. This study considers the PESERA-DESMICE modelling approach to capture a greater range of climatic conditions to assess the potential effect of an improved agricultural management practice emerged from field trials as a promising strategy for enhancing food security and reducing soil and land degradation. The model considers the biophysical and socio-economic benefits of the improved soil conservation technique (T3) - residue mulch combined with pigeon-pea hedges and an organic amendment, against a local baseline practice (T0). The historic rainfall statistics and 50-year rainfall realizations provide a unique time-series of rainfall and an envelope of the potential crop yield. Envelopes of potential biomass production help express the agricultural risk associated with climate variability and the potential of the conservation measures to absorb the risk, highlighting the uncertainty of a given crop yield being achieved in any particular year. T3 elevates yield under both sub-humid and semi-arid climates with greater security for sub-humid areas even though risk of crop failure still exists. The yechnology offered good potential to increase yields by 20% in 42% of the dryland area in Santiago Island and reduce erosion by 8.6-Mg ha-1 , but in terms of cost effectiveness, it might be prohibitively expensive for farmers lacking inputs. The findings can enable the assessment of policy options at larger scale or influence adoption of improved conservation measures under the climatic variability of the Cabo Verde drylands and resilience to future climate change
CaractĂ©risation physico-chimique des eaux rĂ©siduaires de tannerie: cas de lâusine TAN ALIZ Ă Ouagadougou / Burkina Faso
Les activitĂ©s de tannage consistent en la transformation de la peau animale en cuir par Ă©limination des lipides et des poils. Deux procĂ©dĂ©s sont utilisĂ©s pour cela : le tannage au chrome et le tannage vĂ©gĂ©tal. Danscette optique, les industries de tannerie emploient plusieurs rĂ©actifs chimiques et produisent dâĂ©normes quantitĂ©s dâeaux rĂ©siduaires et de dĂ©chets solides. Nous nous intĂ©ressons dans cette Ă©tude Ă lâanalyse des eaux usĂ©es sortant de TAN ALIZ, une unitĂ© industrielle de tannerie de la ville de Ouagadougou, afin de dĂ©terminer si leurs rejets dans la nature aprĂšs traitement ne constituent pas une pollution pour lâenvironnement. Cette Ă©tude, qui a Ă©tĂ© effectuĂ©e durant la pĂ©riode de juillet Ă septembre 2010, fait apparaĂźtre que: les nitrates et les sulfates ne constituent pas de pollution du milieu naturel ; les phosphates, le chrome VI, les MatiĂšres enSuspension (MES), la conductivitĂ© Ă©lectrique ont des teneurs dĂ©passant les normes admises. Ces eaux constituent donc une pollution pour la nature ; la Demande Biochimique en OxygĂšne (DBO5) prĂ©sente des valeurs largement supĂ©rieures Ă 30 mg/L, norme OMS confirmant lâexistence dâune pollution organique.Mots clĂ©s : TAN ALIZ, MES, Chrome VI, DBO
Setting partnership for climate change adaptation in the CCAFS Yatenga site, Burkina Faso: analysis of gaps and opportunities
This paper analyzes patterns of social interaction within the organizations working in the Yatenga
province of Burkina Faso, and develops purposive partnership framework that can facilitate the
scaling up of the action research outputs and outcomes. A diagnostic tool for evaluating group functioning
was used to elucidate the current situation of partnership development in this province. Further,
partnership and networking was analyzed using the network density which describes the portion of the
potential connections in a network of organizations that are actual connections. The results suggest that
the desired partnership as requested/expected by stakeholders is far from working as it could be. The
stakeholders therefore agreed that network density need to be increased for future partnership, with
clearly defined vision, shared responsibilities in generating knowledge and results, and capacities to
monitor, evaluate and communicate on the program impacts. For this purpose, future partnership need
to combine scale-based and competency-based frameworks to be beneficial at scale and pulling together
organizationsâ competencies. Implementing both frameworks would lead to an effective partnership on
climate change adaptation in agriculture and food security. However, the successful development of this
purposive partnership will require capacity development for the group of partnering organizations
Seed systems and crop genetic diversity in agroecosystems
Poster presented at the First Diversitas Open Science Conference. Oaxaca (Mexico), 9-12 Nov 200
Allelic and genotypic frequencies of ASIP and MC1R genes in four West African sheep populations
In West Africa, consumers pay a major attention on the coat colour of the sheep due to religious and cultural reasons. White coated individuals reach selling prices up to three-fold higher than black coated sheep. The aim of this study was to ascertain the genotypic and allelic frequencies of MC1R and ASIP genes in order to assess possible implementation of breeding programmes focusing on the increase of the white coated sheep frequencies. A total of 113 individuals belonging to three Burkina Faso sheep breeds (Burkina-Sahel, Djallonké and Mossi) and one Niger sheep breed (Touareg) were genotyped for the MC1R and ASIP genes. The wild allele of the ASIP gene (Awt; 54.30%) was the most frequent in the four West African sheep, particularly in Burkina-Sahel (85%) and Touareg breeds (80%). The dominant black ED allele was not identified in Burkina-Sahel and Touareg. Most of the analysed individuals were homozygous for wild MC1R allele (E+/E+) with 100, 73.5, 59 and 100% frequency in Burkina-Sahel, Djallonké, Mossi and Touareg, respectively. The Awt/Awt was the most frequent genotype on the ASIP gene in the four West African breeds (80.53%). No individuals were homozygous for the deletion (allele Adel). Although, no routine methods for detection of the genetic basis of the recessive black coat colour patterns can be easily implemented, the current results suggest the feasibility of a selection programme aiming at decreasing the frequencies of the dominant black ED allele in Burkina Faso sheep breeds.Key words: Sheep, coat colour, MC1R gene, ASIP gene, Burkina Faso, Niger
Proprietes hydriques des sols dans deux zones a ecosystemes contrastes au Sahel
Les sĂ©cheresses rĂ©pĂ©tĂ©es du Sahel et la pression de la population ont eu un impact nĂ©gatif sur lâenvironnement ont conduit Ă la dĂ©gradation des ressources naturelles. Mais depuis ces deux derniĂšres dĂ©cennies, lâĂ©tat des ressources au Sahel est mitigĂ©. Câest ainsi que, dans certaines zones, on parle de la perte de certaines fonctions du sol. Cette Ă©tude menĂ©e dans le Sahel et dans deux zones Ă Ă©cosystĂšmes contrastĂ©s a portĂ© sur la dĂ©termination des propriĂ©tĂ©s hydrodynamiques et la caractĂ©risation des sols en fonction de lâoccupation des terres afin de dĂ©terminer la capacitĂ© du sol Ă soutenir certaines fonctions. Elle analyse lâinfluence de lâoccupation des terres sur les propriĂ©tĂ©s hydriques des sols. Elle a utilisĂ© un Ă©chantillonnage de sol, des mesures de densitĂ© apparente, dâhumiditĂ© et lâinfiltromĂ©trie Ă succion contrĂŽlĂ©e Ă trois niveaux de tensions en fonction de lâoccupation des terres. Lâanalyse statistique donne des diffĂ©rences significatives en ce qui concerne la variation de lâargile avec la profondeur, trĂšs significatives pour lâanalyse texturale en fonction de lâoccupation des terres. Pour les propriĂ©tĂ©s hydriques, seule la conductivitĂ© hydraulique Ă la tension (-5) et la taille des pores par sites donnent une diffĂ©rence significative. Les rĂ©sultats montrent une dĂ©gradation de la texture qui induit celle de la porositĂ© texturale et de forte valeur de conductibilitĂ© hydraulique Ă Koalma.Mots clĂ©s : ConductivitĂ© hydraulique ; texture du sol ; occupation des terres ; dĂ©gradation ; Sahe
Etude de lâinfluence des modes de transformation sur les teneurs en lycopĂšne de quatre variĂ©tĂ©s de tomates de la rĂ©gion du nord du Burkina Faso
Les traitements thermiques visent Ă stabiliser les aliments pour de longues pĂ©riodes de stockage. Ils induisent des variations dans la composition de lâaliment. Le prĂ©sent travail a pour but dâĂ©valuer lâinfluence des modes de transformation (sĂ©chage, cuisson) sur les teneurs en lycopĂšne de quatre variĂ©tĂ©s de tomates (Mongal F1, Tropimech, Royale et Rio Grande) de la rĂ©gion nord du Burkina Faso. Les rĂ©sultats en milligrammes de lycopĂšne par gramme de tomates sont ainsi exprimĂ©s : PurĂ©e : Tropimech (0,065), Mongal F1 (0,028), Royale (0,051) et Rio Grande (0,045. AprĂšs les traitements on a notĂ© les Ă©volutions suivantes : SĂ©chage Ă lâombre : Tropimech (- 0.009), Mongal F1 (+0.009) Royale (-0.010) et Rio Grande (-0.009). SĂ©chage solaire : Tropimech (-0.021), Mongal F1 (-0.007) Royale (-0.011) et Rio Grande (-0.014). Cuisson : Tropimech (-0.038), Mongal F1 (-0.014), Royale (-0.025) et Rio Grande (-0.024). SĂ©chage solaire puis cuisson : Tropimech (-0.044), Mongal F1 (-0.017), Royale (-0.038) et Rio Grande (-0.0035). SĂ©chage ombre puis cuisson: Tropimech (-0.045), Mongal F1 (-0.018), Royale (-0.035) et Rio Grande (-0.033). Dâune maniĂšre gĂ©nĂ©rale, les teneurs en lycopĂšne ont subi une baisse au cours de la transformation.Mots clĂ©s : Tomates, lycopĂšne, mode de transformation
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