In a world facing increasing threats from droughts and wildfires, botanists from the University of California, Riverside (UCR) argue that now is the time to identify the conditions that lead to plants extinction. Their findings, published in the Oxford Academic journal Conservation Physiology, propose a new strategy for plant conservation. By understanding the limits beyond which a plant’s vital functions cease, scientists can develop more effective conservation plans.
CRITICAL LIMITS
Louis Santiago, a botany professor at UCR and the paper’s corresponding author, emphasizes the importance of measuring these critical limits. “We can measure the amount of water loss plants can tolerate before they start to wilt, and we can learn the temperature at which photosynthesis stops for different kinds of plants,” he explains. This approach goes beyond assessing the current state of plants and focuses on predicting when they might fail, making it crucial for conservation efforts.
The UCR team argues that knowing a plant species’ physiological status during periods of stress, which are becoming increasingly common due to rising temperatures and drought, can provide valuable insights. By combining this knowledge with critical limit data, conservation resources can be allocated more effectively, allowing for early identification of plants at risk of local extinction.
However, it’s worth noting that critical stress limits are not well-established for most plant species. Out of approximately 700,000 plant species on Earth, only about 1,000 have known critical limits. This highlights the need for further research in this field.
THE PRESSURE
Plants, like people with high blood pressure, can endure stress for a short period and recover. For instance, houseplants wilt when deprived of water but can bounce back when adequately watered. Nevertheless, extended periods of wilting can be detrimental.
Santiago’s research focuses on plant physiology, with an increasing emphasis on studying critical limits. This shift in research direction began after observing the impact of the last drought on plant species. For their recent paper, Santiago and his students measured the leaf wilting points for six species of Southern California chaparral shrubs, shedding light on the importance of critical limit data in conservation.
Santiago advocates for collaboration among plant physiologists, conservation biologists, and land managers to identify and protect vulnerable plant species. He also encourages plant enthusiasts to get involved with native plant societies and engage in activities such as removing invasive species and participating in volunteer projects.
As climate change presents challenges to plant survival, a strategic and collaborative approach is essential to safeguarding plant biodiversity.
