Unlocking Nature’s Secrets: How Plants Adapt to Heat Stress for Survival in a Warming World

Australia is feeling the heat this summer, and plants are struggling. With high temperatures and long periods of heat, many plants face serious risks. This can harm their health and ability to grow, affecting ecosystems and food supplies.

Understanding how plants deal with heat stress is essential. Plant ecologist Associate Professor Andy Leigh from the University of Technology Sydney (UTS) studies this. She explores how plants adapt in extreme climates and why they are crucial to our environment.

“Plants are essential for food, shelter, and cooling our surroundings,” says Leigh. “Even in the harsh deserts of Australia, you’ll find vegetation.”

Many plants have evolved interesting strategies to cope with heat. For example, the shape and color of leaves can impact how heat affects them. In hot regions, many plants have pale, waxy leaves to reflect sunlight and prevent overheating. Smaller leaves also help retain water and keep cooler.

But when drought and heat waves hit together, it can be catastrophic. Heat stress reduces photosynthesis, which is how plants make energy, and affects their growth and reproduction.

A recent study by UTS Ph.D. candidate Alicia Cook shows that a plant’s ability to handle heat is based more on cumulative heat exposure than just the highest temperatures. This idea compares to food safety practices where longer exposure at lower temperatures can still cause harm.

“We found that just like bacteria, plants have a similar response to heat,” Leigh explains. “This helps us understand how plants react to the heat they experience in nature.”

Both plants and humans feel the impacts of extended heat. Continuous exposure leads to more health issues for us, but some plants can actually become more resilient through minor heat stress.

Leigh’s work extends beyond theoretical knowledge. She recently collaborated on a project in Kosciuszko National Park, focusing on plant communities that are threatened by climate change. This research looks at how different genetic strains of alpine plants respond to heat, helping to choose resilient species for restoration efforts.

“As temperatures rise, cold-tolerant plants face new challenges, including less snow cover for protection,” Leigh warns. “We’re using advanced equipment to simulate heat waves and study their effects on these plants.”

Home gardeners often struggle during heat waves. Too much heat can cause plants to wilt or lose leaves. To protect them, water the base of the plants thoroughly and do it in the early morning or late evening when it’s cooler.

“Like humans sweat to cool down, plants release water through tiny pores in their leaves, known as stomata,” Leigh explains. “This process cools them down.”

Using mulch to keep the soil moist and placing plants in shaded areas can help them survive intense heat. Even grouping plants together can create a cooler microclimate.

Learning how plants react to extreme heat is vital for conservation and agriculture. By identifying which species are most vulnerable, we can better prepare for a future where both plants and people thrive.