Drought resistance

Definition

Drought resistance refers to the ability of plants and ecosystems to withstand periods of low water availability, adapting their physiological and structural traits to survive harsh conditions. This trait is crucial in regions with seasonal droughts, influencing biodiversity, ecosystem productivity, and species survival.

5 Must Know Facts For Your Next Test

1. Drought resistance can involve various adaptations, such as deep root systems that access groundwater or waxy leaf coatings that reduce water loss.
2. Some drought-resistant plants enter a state of dormancy during extreme droughts, conserving energy and resources until conditions improve.
3. Ecosystems with high drought resistance often support a greater diversity of species, as they provide niches for plants and animals adapted to arid conditions.
4. Climate change is increasing the frequency and intensity of droughts, making drought resistance an essential trait for many species to survive in a changing environment.
5. Agricultural practices increasingly focus on selecting drought-resistant crops to ensure food security in regions prone to water scarcity.

Review Questions

• How do drought-resistant plants adapt their physiological traits to survive periods of low water availability?
  • Drought-resistant plants develop various physiological adaptations such as deep root systems that can reach underground water sources and reduced leaf surfaces to minimize evaporation. They may also modify their stomatal behavior by closing them during the hottest parts of the day to conserve water. Additionally, some plants store water in specialized tissues or produce compounds that help retain moisture, allowing them to endure prolonged dry spells.
• Discuss the role of drought resistance in maintaining biodiversity within arid ecosystems.
  • Drought resistance plays a significant role in sustaining biodiversity in arid ecosystems by enabling various plant and animal species to thrive under limited water conditions. Species that have developed drought-resistant traits can occupy different ecological niches, allowing them to coexist despite competition for resources. This adaptation helps maintain a balanced ecosystem where diverse organisms contribute to nutrient cycling and habitat stability, supporting a wide range of wildlife.
• Evaluate the impact of climate change on the evolution of drought resistance in plant species and its implications for agricultural sustainability.
  • Climate change is leading to increased temperatures and more frequent droughts, which puts pressure on plant species to evolve better drought resistance. This shift can result in a selection for traits that enhance survival under water-limited conditions, influencing crop breeding programs aimed at agricultural sustainability. The development of drought-resistant crops can ensure food security by enabling farming in areas that may become increasingly arid due to climate change, thus maintaining agricultural productivity in a rapidly changing environment.

Related terms

Xerophyte: Plants that are specially adapted to survive in environments with very little water, such as deserts.

Stomatal Regulation: The process by which plants control the opening and closing of stomata to minimize water loss during dry conditions.

Water-Use Efficiency: The ratio of carbon dioxide fixed during photosynthesis to the amount of water lost through transpiration, indicating how efficiently a plant uses water.