EFFECT OF CLIMATE CHANGE ON GRAPEVINES PHENOLOGICAL STAGES AND YIELD UNDER ARID ENVIRONMENT

Abstract

Climate change is a dramatic crisis that has left severe impacts on the agricultural sector and especially on viticulture. Phenological sets over 41 years and annual climatic anomalies ’data over the same years’ intervals were procured. An earliness in Al Ahsa region, the first signs of climate change were detected starting 1997, where annual precipitable water and temperature anomalies were the most important climate influencers all phenological events occurred for the varieties White and Red, from the beginning of budburst until harvest. Moreover, the yield of both varieties was slightly reduced between 1997 and 2019 in comparison with the interval of years 1979-1996. Beginning of budburst, budburst, 2-3 leaves unfolded and visible inflorescence were positively correlated with the annual wind speed anomaly. Beginning of flowering, full flowering, beginning of fruit set, full veraison, and harvest were positively with the annual total cloud cover anomaly and annual total precipitation anomaly. In addition, the full fruit set and beginning of veraison were positively correlated with annual wind speed anomaly, and negatively correlated with annual precipitable water anomaly. Yield was positively correlated with annual total precipitation anomaly and annual total cloud cover anomaly. Results suggest the adoption of a drip irrigation system in Al Ahsa vineyards that would overcome the low water availability in hot summers and reduce soil salinity, one of the biggest issues facing Gulf countries.