Estimating Rice Yield under Changing Weather Conditions in Kenya Using CERES Rice Model

W O Nyang’Au,R K Wanjogu,B M Mati,L K Kiplagat,K Kalamwa

doi:10.1155/2014/849496

Abstract

Effects of change in weather conditions on the yields of Basmati 370 and IR 2793-80-1 cultivated under System of Rice Intensification (SRI) in Mwea and Western Kenya irrigation schemes were assessed through sensitivity analysis using the Ceres rice model v 4.5 of the DSSAT modeling system. Genetic coefficients were determined using 2010 experimental data. The model was validated using rice growth and development data during the 2011 cropping season. Two SRI farmers were selected randomly from each irrigation scheme and their farms were used as research fields. Daily maximum and minimum temperatures and precipitation were collected from the weather station in each of the irrigation schemes while daily solar radiation was generated using weatherman in the DSSAT shell. The study revealed that increase in both maximum and minimum temperatures affects Basmati 370 and IR 2793-80-1 grain yield under SRI. Increase in atmospheric CO2concentration led to an increase in grain yield for both Basmati and IR 2793-80-1 under SRI and increase in solar radiation also had an increasing impact on both Basmati 370 and IR 2793-80-1 grain yield. The results of the study therefore show that weather conditions in Kenya affect rice yield under SRI and should be taken into consideration to improve food security.

Highlights

Agriculture is always vulnerable to unfavorable weather events and climate conditions
The four irrigation schemes were chosen to allow for comparative analysis since they occur in different regions of the country of diverse variations and to make model calibration and validation possible
According to Hay and Walker, [20] the primary atmospheric variables that impact on crop growth are solar radiation, air temperature, humidity, and precipitation

Summary

Introduction

Agriculture is always vulnerable to unfavorable weather events and climate conditions. Despite technological advances such as improved crop varieties and irrigation systems, weather and climate are important factors, which play a significant role in agricultural productivity [1]. The impacts of climate change on agricultural food production are global concerns and, for that matter, Kenya is not an exception. Climatic factors such as temperature, rainfall, atmospheric carbon dioxide, and solar radiation, among others, are closely linked to agricultural production. An analysis of the trends in temperature, rainfall, sea levels, and extreme events points to clear evidence of climate change in Kenya. Other projections indicate increase in mean annual temperature of 1 to 3.5∘C by the 2050s [4]

Methods

Results

Conclusion