ASSESSMENT OF CLIMATE CHANGE IMPACTS ON CROP YIELD AND CROP WATER PRODUCTIVITY – SEMINAR CLIMATE CHANGE VULNERABILITY & ADAPTATION 2015
In this study, surface water balance analysis for the components (precipitation, crop and actual evapotranspiration, and runoff) for the selected states were conducted over 50 years (2010 to 2060) by using downscale hydro-climate data of CCSM3(A1B), ECHAM5(A1B1), ECHAM5(A1B2), ECHAM5(A1B3) and MRI(A1B). The results showed that an area of higher precipitation and runoff is located in Perak, followed by Pahang and Johor. Temperature, ETcrop and AET were higher in Johor, followed by Pahang and Perak. Mann-Kendall trends suggested statistically significant positive trends in mean monthly temperature, ETcrop (except Pahang) and AET. No trend was detected for precipitation and runoff. The findings show strong relationships between temperature with ETcrop and AET. The declining trend in precipitation and warmer temperature resulted in a lower soil water availability in the future. Drought potential was analysed using Standardise Precipitation Index (SPI) on both historical and future rainfall data. The percentages of wet events in the future are expected to increase by 65%, 69% and 16% for Johor, Pahang and Perak respectively. In those events the extremely wet would increase by about double for Johor and Pahang and about 43% for Perak. The percentages of dry events are also expected to increase by 45% (Johor) and by 9 % for both Pahang and Perak. However, the percentages of extremely dry decrease by almost 30% for Johor and about 76% for Pahang. Future trends of oil palm yield for Johor and Pahang are expected to decrease based on non-parametric Mann-Kendall test that the yield would decline by 0.10% per year for Johor while decline by 0.24% per year in Pahang. Results on trend analysis also indicated that significant increasing trend in simulated temperature series are detected for Johor and Pahang. As temperature increased, oil palm yields for both states are expected to decline. The results on declining trend of oil palm yield are consistent with the risen in temperature series. From year 2020 to 2060, Pahang would show the highest percentage in decreasing oil palm yield. Analysis for rubber yield, static model results suggest that only two realizations, namely ECHAM5(A1B2) and MRI(A1B) showed extreme rainfall patterns from 2010 – 2060 for FELDA Tawai in Perak. Based on ECHAM5(A1B2) dataset, the dry period is at FELDA Tawai is expected to occur between years 2016 and 2020. This would reduce rubber production by 6.7% and prolonged the immature period by 0.5 year compared to normal condition (no climate change). Based on the MRI(A1B) dataset, there would be six dry periods between 2010 and 2060. Under this condition, the rubber production is expected to decrease between 12.8% and 24.2% while the immaturity period will be prolonged from 1.1 years to 2.9 years. Based on the CCSM3(A1B) dataset, Kota Tinggi would experience two dry periods between years 2010 and 2060. This would result in rubber yield reduction from 18.2% to 18.6% and prolonged the immaturity period by 1.8 years
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Abstract
In this study, surface water balance analysis for the components (precipitation, crop and actual evapotranspiration, and runoff) for the selected states were conducted over 50 years (2010 to 2060) by using downscale hydro-climate data of CCSM3(A1B), ECHAM5(A1B1), ECHAM5(A1B2), ECHAM5(A1B3) and MRI(A1B). The results showed that an area of higher precipitation and runoff is located in Perak, followed by Pahang and Johor. Temperature, ETcrop and AET were higher in Johor, followed by Pahang and Perak. Mann-Kendall trends suggested statistically significant positive trends in mean monthly temperature, ETcrop (except Pahang) and AET. No trend was detected for precipitation and runoff. The findings show strong relationships between temperature with ETcrop and AET. The declining trend in precipitation and warmer temperature resulted in a lower soil water availability in the future. Drought potential was analysed using Standardise Precipitation Index (SPI) on both historical and future rainfall data. The percentages of wet events in the future are expected to increase by 65%, 69% and 16% for Johor, Pahang and Perak respectively. In those events the extremely wet would increase by about double for Johor and Pahang and about 43% for Perak. The percentages of dry events are also expected to increase by 45% (Johor) and by 9 % for both Pahang and Perak. However, the percentages of extremely dry decrease by almost 30% for Johor and about 76% for Pahang. Future trends of oil palm yield for Johor and Pahang are expected to decrease based on non-parametric Mann-Kendall test that the yield would decline by 0.10% per year for Johor while decline by 0.24% per year in Pahang. Results on trend analysis also indicated that significant increasing trend in simulated temperature series are detected for Johor and Pahang. As temperature increased, oil palm yields for both states are expected to decline. The results on declining trend of oil palm yield are consistent with the risen in temperature series. From year 2020 to 2060, Pahang would show the highest percentage in decreasing oil palm yield. Analysis for rubber yield, static model results suggest that only two realizations, namely ECHAM5(A1B2) and MRI(A1B) showed extreme rainfall patterns from 2010 – 2060 for FELDA Tawai in Perak. Based on ECHAM5(A1B2) dataset, the dry period is at FELDA Tawai is expected to occur between years 2016 and 2020. This would reduce rubber production by 6.7% and prolonged the immature period by 0.5 year compared to normal condition (no climate change). Based on the MRI(A1B) dataset, there would be six dry periods between 2010 and 2060. Under this condition, the rubber production is expected to decrease between 12.8% and 24.2% while the immaturity period will be prolonged from 1.1 years to 2.9 years. Based on the CCSM3(A1B) dataset, Kota Tinggi would experience two dry periods between years 2010 and 2060. This would result in rubber yield reduction from 18.2% to 18.6% and prolonged the immaturity period by 1.8 years
Citation
IR. MOHD ZAKI MAT AMIN, IR. MARINI MOHAMAD IDERIS , NURUL HUDA MD. ADNAN, TS. HJ. ZUBAIDI JOHAR, NUR ELYASABATH MOHD GHAZALI, NUR AIZA MOHAMAD, GS. KHAIRUL ANAM MUSA MAHMUD. 2015. ASSESSMENT OF CLIMATE CHANGE IMPACTS ON CROP YIELD AND CROP WATER PRODUCTIVITY – SEMINAR CLIMATE CHANGE VULNERABILITY & ADAPTATION 2015. Digital NAHRIM Publication Repository.