Spatiotemporal Variation of Vegetation and Its Responses to Climate Change in Pakistan

Abstract

Vegetation change and its relationship with climate factors are important for ecosystem stability, especially in arid and semiarid regions for climate change adaptation. However, the individual contribution of temperature and precipitation variations to vegetation cover in Pakistan remains uncertain. This study assesses changes in vegetation dynamics and their relationship with climatic variables in Pakistan from 2001 to 2021 using Moderate Resolution Imaging Spectroradiometer Normalized Difference Vegetation Index (NDVI) data and multiple linear regression analysis. Our aim was to investigate why vegetation is unevenly distributed across the study area, as understanding this distribution is crucial for adaptation to climate change. The results show that the NDVI has significantly increased in the study area over the past 21 years, whereas temperature and precipitation have only slightly increased. The spatial variation of precipitation is distinct, with the north receiving more precipitation than the south. In arid and semiarid regions, both temperature and precipitation positively influence NDVI. Moreover, in the autumn season, the positive impact of climatic factors on vegetation cover was higher than in the other seasons. The results indicate that precipitation influences vegetation dynamics in areas with an annual average precipitation between 18.38 and 25.01 mm/year, while temperature dominates in regions with an annual average precipitation below 18.38 mm/year or above 25.01 mm/year. This finding provides scientific evidence of climate change’s impact on vegetation and can help governments create effective policies to protect it. Graphical Abstract