Application of Earth Observation data in Agricultural drought monitoring Farai Kuri University of Zimbabwe

Introduction  Drought traditionally measured using rainfall data  Rainfall indices an indirect measure of drought  Remote sensing drought indices are plant based  EO is therefore a direct measure of plant performance

Objectives  To test whether and to what extent EO based drought indices can predict maize yield in Zimbabwe

Materials and Methods

Study area  Study was based on the whole of Zimbabwe

Data  Maize yield data courtesy of Ministry of Agriculture Mechanisation and Irrigation Development ( & )  SPOT VGT NDVI long-term series AMESD Station at SIRDC and UZ ( )

Data Analysis  Calculated Vegetation Condition Index (VCI) from SPOT NDVI series  VCI<36%, Dry dekad (1), Not Dry ( 0)  Frequency of dry dekads calculated for &

Relating Drought to Maize Yield  Regression was used to test whether and to what extent EO based dry dekads can predict maize yield.

In-Situ Maize Yield

Frequency of Dry Dekads ( )

Results

In-Situ Maize Yield

Frequency of Dry Dekads ( )

Y=1/( * x R²=0.91 P-Value=0.001

Conclusion  There is a significant relationship between frequency of RS based dry dekads and maize yield  Therefore frequency of RS based dry dekads can be used to evaluate impact of drought on yield or to estimate crop yield

Thank You