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Leclerc c 20150709_1500_upmc_jussieu_-_amphi_15

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Leclerc c 20150709_1500_upmc_jussieu_-_amphi_15

  1. 1. Climate Variability as Experienced by Farmers C Leclerc, C Mwongera, V Moron
  2. 2. © C. Mwongera, Cirad  Rainfall variability and droughts have historically been major causes of famines affecting particularly smallholder rain-fed agriculture  The high drought risk areas identified around the world coincide with higher levels of poverty (Hyman et al. 2008, Waddington et al. 2010)  However, impact of climate variability is mostly assessed by considering current species and varieties, without taking into account multicropping systems and dynamics in time and space Rainfall variability and traditional farming systems
  3. 3. Multicropping systems dynamics in dryland of Kenya 3 Sharp decline for sorghum and millet (drought tolerant) Is the cropping system more sensitive to drought at present than in the past? Increase in maize popularity (drought sensitive) Leclerc et al. 2014. Wea Clim Soc 6 (3)
  4. 4. Farmers’ experience on seed losses and climate variations 2010 200019841975 Year of crop adoption Year of abandon Year of variety losses Climatic reason for loss 2050 Hypothetical rainfall No dynamic / one crop Known rainfall Dynamic When and Why Projection into the past Projection into the future
  5. 5. Questions 1. Does farmers' knowledge and perception of past climate correlate to rainfall variables? 2. Is retrospective analysis useful in assessing cropping system adaptability to climate change?
  6. 6. 6 Farmers knowledge accuracy on past climate  208 farmers at 3 altitudes (750, 950 and 1100 m)  Rainfall data (1961-2006) 3 stations matched to surveyed farmers  3200 events of variety losses  Reasons for loss due to rainfall patterns - Drought =74% - Heavy rainfall = 9% Farmers study sites Rainfall stations : 1. Ishiara (872 m) 2. Mitunguu (1189 m), 3. Embu (1433 m)
  7. 7. 7 Farmers’ declarations coincides with past droughts • Farmers declaration of droughts correlated to low rainfall values • Fuzzy picture of what a drought is in intermediate climatic situations • The reverse pattern is observed for heavy rainfall with a positive slope Nkari tagwe T9 Kithukio Drought Heavy rainfall Ordered rainfall values Pearson’sresiduals C. Leclerc, C. Mwongera, P. Camberlin, and J. Boyard-Micheau. 2013 Indigenous past climate knowledge as cultural built-in object and its accuracy. Ecology and Society, 18(4):22. Ordered rainfall values 1984 2000 1961 1971 1981 1991 2001 Years 0 100 200 300 400 500 Frequency
  8. 8. 8  Seed loss probability increases below 400 mm (drought) and above 700 mm seasonal amount (heavy rainfall), according to farmers’ experiences  It also increased for rainy seasons shorter than 50 days, and with less than 28 rain days Climate risk based on farmers’ experiences Leclerc, C., C. Mwongera, P. Camberlin and V. Moron. 2014. Climate variability, droughts and farmers' crop variety losses by East African smallholders. A retrospective survey. Weather, Climate and Society 6 (3).354-370 Pr(loss) Seasonal amount (mm) Drought Heavy rainfall
  9. 9. 9 V C V C Probability to lose a Bean and maize variety (1 and 2) higher than probability to lose a sorghum variety (8) V C Altitude: 1=750m 2=950m 3=1100m Crops: 1=Beans 2=Maize 3=Green gram 4=Pearl millet 5= Cow pea 6= Pigeon pea 7= Finger millet 8= Sorghum V C Probability of loss according to altitudes and crops Leclerc, C., C. Mwongera, P. Camberlin and V. Moron. 2014. Climate variability, droughts and farmers' crop variety losses by East African smallholders. A retrospective survey. Weather, Climate and Society 6 (3).354-370 Pr(loss) Pr(loss)
  10. 10. The cropping system dynamics, favouring maize at the expense of sorghum and pearl millet, is likely to induce an increasing risk of seed loss during drought But climate risk also depends on specific ecological farming conditions, such as altitude The integration of farmers experience and scientific climate knowledge could allow development of drought monitoring that considers both climatic and contextual data Farmers’ perception of drought: conclusion
  11. 11. Farming system resilience as perspective Improved varieties were more negatively impacted than local varieties (10.8% vs 6.4%, p<0.001) Varieties obtained from Kinship ties were less negatively impacted than those obtained from market (6.5% vs 7.4%, p<0.001) The role of informal seed system should be thus crucial in farming system resilience
  12. 12. Thanks for your attention