Spatio-temporal Variability and Climate Change Impact on the Crop Water Requirement of Pigeonpea (Cajanus cajan) - A Case Study, North-Eastern Karnataka, India

Abstract

Background: Global climate change and its impact on crop water requirement have widely discussed in recent years. In the present century, climate change had become a significant concern and atmospheric temperature is the dominant climatic factor that indicates the changes in both regional and global scales. This study was undertaken to evaluate the trend and predict the changes in crop water requirement under various climate change scenarios. Methods: The statistical nonparametric Mann-Kendall test and Sen’s slope used to identify trend in the data series. In this study ArcGIS V. xx software used for investigating spatial patterns in data. CROPWAT-8.0 model used for calculation of crop water requirement under various climate change scenarios. Total six climate change scenarios were considered for assessment.Result: The crop water requirement (ETc) of pigeonpea estimated and exhibited an increasing trend and a decreasing trend in study area in the past 35 years. The spatial distribution maps reveal that the distribution of ETc is found an increasing trend in all the scenarios to reference ETc. An increasing trend of ETc of pigeon pea was observed in all the places under various climate change scenarios. It was suggested to promote rainwater harvesting, soil and water conservation and increase ground water recharge in the study area to minimize the risk of yield reduction due to the availability of minimum water under changing climatic condition.