Refinement of a site classification system for South African plantation forestry using regionally downscaled climate model input

Abstract

Deemed a climate change hotspot, southern Africa is already experiencing increasing average temperatures associated with extreme weather events, such as drought and flooding. Climate change has already induced many weather and climate extremes in South Africa, and these are likely to increase due to continued anthropogenic greenhouse gas emissions, placing the commercial forestry industry at continued risk. This study aimed to assess expected changes in temperature and rainfall for the Mpumalanga and KwaZulu-Natal provinces in South Africa and the integration of modelled climate data into forestry-specific research and planning operations. Climate model data show increased intra-annual rainfall variability, less rainfall in many areas, and shifting climate zones from cool to warm and warm to subtropical. Cool areas in the Mpumalanga region are expected to be most impacted by these temperature increases. The refinement of the site classification system included more climatic variables, and these results will serve as baseline information in the adaptation of forestry management to changing climatic conditions. The study complements other existing projects focused on site-by-genotype matching and tree breeding strategies. Future research will also include strategies to adapt to hotter and drier climates and shifting seasons.