ABSTRACT
Dry tropical biomes are unique ecosystems that experience a short rainy season followed by a marked dry season that exposes plants in these biomes to drought stress. These biomes are widespread across the globe and constitute the transition zone between the moist tropical rainforest and dry desert. The richness of biodiversity in these biomes and their unique adaptive features also contribute to their ecological importance. As climate change continues to intensify, plants in these biomes risk surviving or facing extinction. This chapter explains the stress conditions imposed on plants during dry periods in tropical dry forests and savannas. It also focuses on the drought-adaptive mechanisms in plants and their evolution and deployment for survival through escape, avoidance and/or tolerance. Plant traits for water management—such as those that promote water saving, water sourcing and water use—were also discussed. Physiological regulations of germination, dormancy, deciduous habits and flowering in drought conditions are highlighted. The chapter also examines the impact of changing climate conditions on dry tropical ecosystems with a particular focus on plant responses and adaptations to elevated temperatures, CO2 and water deficit, and how these factors affect the growth and yield of plants. These have great implications on the diversity of tropical vegetation and the ecosystem services that they offer.
