Final answer:
Without regular fire, tropical grasslands in Africa would likely transition to woodlands or forests, potentially decreasing grassland biodiversity and altering the habitat for many large mammal species.
Step-by-step explanation:
If the grass did not dry up and catch on fire each year in the tropical grasslands in Africa, the ecosystem would likely undergo significant changes. One of the primary roles of fire in these grassland ecosystems is to help maintain the balance between different plant species, including grasses and trees. Without fire, there could be an increase in woody vegetation, which could lead to a transition from grasslands to woodlands or forests over time. This change would dramatically alter the landscape, potentially reducing the diversity of large mammals that are adapted to a savanna environment with open grasslands.
As indicated by the information referencing the grass-fire cycle, fire plays a critical role in preventing woody plant encroachment and in maintaining the grassland ecosystem. Fires remove older and dead material, lowering competition and facilitating new growth, which in turn supports high net primary productivity. In the absence of fire, grasslands may begin to lose their characteristic openness as trees and shrubs establish more firmly, decreasing grassland biodiversity and altering the availability of food sources for grazing animals.