Final answer:
Terrestrial plants have adapted to dry soils through mechanisms like drought tolerance, growing in humid regions, desiccation resistance, and structural adaptations such as a thick waxy cuticle, reduced leaf size, spines, and water storage in specialized tissues. Deep or widespread root systems and rapid life cycles timed with rare rainfall events are also key adaptations.
Step-by-step explanation:
Terrestrial plants have developed numerous adaptations to thrive in dry soils and environments. One key adaptation is drought tolerance displayed by plants like mosses, which can survive long periods of dryness by entering a brittle, dormant state and quickly rehydrating when water becomes available. Other plants, such as ferns, prefer to grow in humid conditions where they are less likely to face dehydration. However, plants like cacti demonstrate a desiccation resistance strategy, minimizing water loss so effectively that they can inhabit some of the driest places on Earth.
Furthermore, terrestrial plants have evolved structural adaptations. This includes the development of a waxy cuticle on their leaves and stems, which helps to reduce water loss through transpiration. Additionally, changes such as reduced leaf size, the presence of spines instead of leaves, and the ability to store water in specialized tissues have also greatly enhanced their ability to survive in arid conditions. Another adaptation is the presence of extensive root systems that tap into deep water sources or spread out widely to maximize water absorption from infrequent and brief rainfalls.
Some plants have also adopted life cycles that take full advantage of brief periods when water is plentiful, rapidly completing their growth and reproductive cycle before returning to dormancy. These ingenious adaptations enable plants to not only survive but also reproduce in environments that would otherwise be inhospitable.