Approach to Maize and Wheat Crop Forecast

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2 Approach to Maize and Wheat Crop Forecast Maize and wheat are the main staple food in Kenya accounting for over 80 percent of total cereals used at a household level Rice is the third most consumed cereal Each year the Food Steering Committee (FSC) of the Office of State, Special Programmes require information on Area, Yield and Production these cereals

3 Prediction of Crop Production Production = Area * Yield

4 Population growth and Shrinking land base of Kenya

5 Kenya s projected rural and urban population, Population as of 2010 By 2030, it is projected that 33 per cent of Kenyans will live in urban areas

6 Agriculture expansion between 1990 s and 2000 s Population of Kenya in 2009 census = 38,610,097 people 20 % of Kenya support crop cultivation significant to the economy Kenya requires approx 34 million bags of maize and 9 million bags of wheat annually Balance in food deficit met by substantial quantities of rice produced locally and imports

7 METHODS Estimation of area crop using vertical aerial photography Determination of crop yield per hectare Computation of crop production Computation of consumption

8 METHODS: ESTIMATION AREA Aircraft: High winged twin or single engine (P68 or Cessna ) Flying height of 1600 ft Camera: A 35 mm camera, 20 mm wide-angle lens GPS: Set to UTM WGS 84 datum or Geographic Photographs: Vertical Scale is approx. fixed

9 Photo Interpretation: Dot-Grid technique N # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # Meters # 100 Dot grid Source: DRSRS, 2004

10 Photo Interpretation: 100 Dot-Grid

11 Photo Interpretation: 150 Dot-Grid

12 Photo Interpretation: 200 Dot-Grid

13 Sample Dot-Grid for Vertical Photograph Photograph taken 5Km 2.5Km 9261 photos to cover entire stratum Cost: US D 72,375 Cost per photo: USD 7.8

14 Area of Crop S.F = Oρ/η Where: S.F = Sampling Fraction of the strata Oρ = Total No. of sample photos observed with crop η = Total No. of photos taken in district strata n Hence: A = S.F ΣC (1/ Oρ *100) i Where: A = Area of survey stratum (ha) S.F = Sampling Fraction of the strata Oρ = Total No. of sample photos observed with crop n = n th photo in the strata i = i th photo in the strata

15 Accuracy levels in Photo Interpretation

16 Satellite Data for Determination of Crop Strata 14 satellite scenes Cost: free for landsat Cost: Aster = US D 1,520 Economical

17 Satellite Data for Determination of Crop Strata

18 METHODS: DETERMINATION OF CROP YIELD Tektronix J16 digital radiometer Applies Remote Sensing Techniques a ratio of nearinfrared and red band reflectance (NIR-VIS)/(NIR+VIS) is a surrogate for primary production Tussled maize NIR nm VIS nm

19 Collateral Information Crop calendar LGP Seasonal progression of rainfall pattern Agronomic practices Soil moisture ETP Crop growth model Source: MoA, 2004

20 Crop Calendar Long rains maize planting begin in S. Rift, Kisii, Migori, Kuria Long rains maize planting begin Western &N. Rift Kenya, Nyanza Long rains maize harvest begins S. Rift Kisii, Migori, Kuria Final long rains maize harvest Short rains maize harvest Short rains season begins Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Land preparation Monitor season progression, LGP, CP Long rains maize harvest begins Western &N. Rift Kenya, Nyanza and rest of grain basket Local conflict Policy Subsudy

21 PRODUCTION & STORAGE Driers P = Y*A Silos Storage

22 Maize consumption/production Average consumption rate being 98 Kg per person per year (FEWSNET, 1997) Source: DRSRS Database )

23 Wheat Bags Millions Consumption Production Year Average consumption rate of wheat being 27 Kg per person per year (FEWSNET, 1997 Source: DRSRS Technical

24 RECOMMENDATION Increase crop yield, area appear to remain relatively constant Increase field checks to improve the Confusion Connotation matrix Move towards sampling area frames Review relationship between yield and NDVI Increase and enhance collateral information sources

25 END ASANTE SANA