Climate Change and Its Impact on Agriculture Productivity of Nuwakot District

Abstract

Agriculture is very much sensitive towards climatic variability. Changes in climatic factors like temperature, solar radiation and precipitation have potentials to influence crop production. Nepalese economy depends largely on agriculture which contributes 42% of the total GDP. In this regard an attempt has been made to investigate the effect of climatic variability on the paddy, wheat and maize yield in plant ationmaturity and harvest period in Nuwakot district. The climate variables analyzed in this study are temperature,and rainfall. These two variables are used to explore the relation of climate to the paddy, wheat and maize yield based on 20 years of data records from 1990 to 2009. The regression analysis was carried out to study the climatic trend also the correlation analysis is carried out between the backward difference filtered climatic parameters and the backward difference filtered cropyield. Over the last 20 years the mean temperature increased by 0.051 VII 0 C per year.Therehas been 0.06 0 C per annum increase in maximum temperature and 0.006 C perannum increase in minimum temperature.. The warmest year was 2009 with the mean maximum temperature of 29.19 0 C.Regarding the rainfall, total mean annual rainfall was of 1922.7 mm with mean annual rainfall of 155.72 mm in the district.The year 2002 remained the wettest year with total mean annual rainfall of 2285.6 mm and the year 2006 was the driest year over the study period with total annual rainfall of 1254.4 mm. The present study concludes that increase in temperature and increase in rainfall is favorable condition for paddy yield .In case of wheat increase in temperature and rainfall is favorable in plantation period only,the condition is reverse in maturity and harvest period. However in case of maize decrease in temperature and increase in rainfall is favorable for both plantation and harvest period.The impact of irrigation in crop yield has not been considered in this study.Furthermore, the complex relationship between crop and climate should be studied in detail taking into account of the multiple relations between various meteorological variables.