How trees adapt and surpass expectations amid climate change
Trees possess the capacity to adjust to the evolving climate, and a recent study provides insights into this phenomenon.
- Trees worldwide face multifaceted challenges due to climate change.
- Contrary to conventional beliefs, new research unveils surprising patterns in tree sensitivity.
- A recent study highlights the crucial role of adaptability and genetic diversity in trees, offering insights into conservation strategies for a changing climate.
Climate change undeniably shapes our planet’s future, with its influence reaching into our ecosystems. Among the most silent observers of this metamorphosis are the trees of the world.
According to research, there is a net loss of 10 billion trees each year. This decline represents more than just a numerical value; it signifies a substantial decline in the Earth’s natural infrastructure and the services that forests provide, like biodiversity support and climate regulation.
A new study by scientists from the University of California, Santa Barbara (UCSB) and the University of California, Davis, investigates the sensitivity of trees to drought across different climatic regions.
As we dive into the research, it becomes evident that the effects of climate change on trees are multifaceted. It’s not merely a matter of numbers; rather, it involves comprehending how various species react to shifting climatic conditions.
The trees’ sensitivity to drought, a critical aspect explored in the study, sheds light on the intricate interplay between climate patterns and tree health.
Co-author of the study, Prof. Joan Dudney from UCSB, spoke to Interesting Engineering (IE), stating reduced dieback in trees from drier Californian regions during the 2012-2016 drought as a motivation for their current work.
She explained, “I found this contradicted current scientific notions. Interestingly, it supported studies indicating that spoiled trees—those with ample water resources—were more drought-sensitive. This prompted a global investigation, facilitated by the International Tree Ring Data Bank, to test the consistency of these patterns on a larger scale.”
Tree sensitivity across climate gradients
The researchers started with a meticulous analysis of 6.6 million tree ring samples. This extensive study spanned 122 species worldwide, utilizing tree ring samples as a reliable indicator of annual growth.
The global scale of the research sought to provide a comprehensive understanding of how trees respond to drought in various climate conditions.
The dataset was then cross-referenced with historical climate data, including precipitation and temperature, revealing the patterns at play.
Contrary to prevailing beliefs, the research uncovered a surprising pattern: trees in global wetter regions exhibit a heightened sensitivity to drought, and not vice versa! This finding challenges the conventional wisdom that trees in drier environments are more vulnerable.
By projecting growth changes up to 2100, the study showed an unexpected vulnerability in wetter, hotter regions, suggesting that our understanding of climate change’s effects on forest stability in these areas has been underestimated.
The study also delved into the evolutionary dynamics of trees in response to changing climates.
“By standardizing growth across species’ climatic niches, it’s possible to look for differences in sensitivity and draw links to adaptation. As tree populations adapt to their environments over time, changes in climate across a species’ range create expectations of diverse adaptations, resulting in genetic variation,” explained Prof. Dudney.
Impact of climate change on forest health
Spoiling
The findings of the study not only challenge traditional beliefs about trees’ vulnerability to drought but also introduce a novel concept— the “spoiling” of trees in wetter regions.
This phenomenon, where trees with greater access to water resources show heightened sensitivity to drought, has significant implications for the future of global forest ecosystems.
Additionally, this unexpected vulnerability challenges previous assumptions about which forests are most threatened by climate change.
Climatic changes
By analyzing growth trends and projecting changes up to 2100, the research provides a glimpse into the anticipated climatic shifts across species’ ranges.
The predictions indicate a substantial challenge for many tree species. Over 11 percent of the average species’ range is expected to face a new climate by 2100. This implies conditions that differ significantly from those the species currently experience, posing a considerable risk to their long-term survival.
Climatic variables
The study also delves into specific climatic variables, highlighting two: Potential Evapotranspiration (PET) and Climatic Water Deficit (CWD).
These factors are crucial in determining the stress levels trees experience under changing environmental conditions.
The mean PET is projected to increase as temperatures rise, indicating elevated water loss from evaporation and transpiration. Simultaneously, CWD, a measure of the balance between water supply and demand, is expected to escalate.
These changes collectively contribute to the heightened stress trees face in the wake of climate change.
Genetic diversity and adaptation
Adaptability has emerged as a crucial factor for the survival of trees. This study has explored the practical aspects of genetic diversity and adaptation.
Over time, tree populations develop responses to their surroundings, fostering genetic diversity to adapt to environmental changes.
As mentioned, the study introduces a surprising twist about trees in wetter regions serving as a genetic reservoir and displaying heightened sensitivity to drought. This finding highlights the intricate ways in which trees adapt to their environments.
The importance of genetic diversity was highlighted by Prof. Dudney, who explained that long-term growth trends can test whether different populations respond differently to extreme events like drought.
“If there are significant differences in drought response, then we can infer that these populations have probably adapted differently over time, leading to spatial variation in the vulnerability of tree populations to climate change,” she said.
Although genetic diversity can provide some degree of protection for forests against the impacts of climate change, trees’ capacity to adapt to drought and changing climates has definite constraints, as illustrated by the unprecedented instances of mortality occurring worldwide.
Practical implications for forest management
The discovery of a reservoir of drought-resistant stock in drier regions provides a tangible example of trees’ adaptability.
These resilient pockets offer valuable insights into the strategies trees employ to survive harsh conditions, opening avenues for conservation strategies, including assisted migration and targeted management interventions based on the wealth of genetic diversity within these resilient trees.
Traditionally, forest management strategies have often centered around areas considered more susceptible to the impacts of climate change, particularly those marked by hotter and drier conditions. However, the study’s unexpected findings urge a re-evaluation of these paradigms.
“We have greatly underestimated the effects of climate change and the stability of forests and their associated carbon stores in wetter regions,” pointed out Prof. Dudney.
The next 50 to 100 years present a critical window for forest management. The anticipated climatic shifts and the vulnerability of wetter, hotter regions underscore the need for adaptive and proactive strategies.
Source: Interesting Engineering
Back to NEWS:
BUSINESS l CLIMATE CHANGE l CONSTRUCTION l EDUCATION l ENVIRONMENT l FORESTRY ENGINEERING l FORESTRY l GOVERNMENT l INTERNATIONAL l LAND l RECYCLING l RESEARCH l ROOFING l SHORT HAUL l SILVICULTURE l SOCIAL RESPONSIBILITY l TRANSPORT l TREATMENT l TRANSPORT l VALUE ADDING