[Progresses of alpine treeline formation mechanism.]

Area of Science:

• Ecology
• Plant Physiology
• Climate Change Research

Background:

• Alpine treelines mark critical boundaries between forest and tundra ecosystems.
• These ecotones are highly sensitive to climate change, serving as key indicators.
• Current treeline formation hypotheses lack global applicability.

Purpose of the Study:

• To summarize mechanisms of alpine treeline formation.
• To investigate the impact of low temperatures on biochemical processes limiting tree growth.
• To identify a generalized hypothesis for global treeline dynamics.

Main Methods:

• Literature review of treeline formation mechanisms.
• Analysis of low temperature effects on photosynthesis.
• Evaluation of impacts on nutrient characteristics, non-structural carbohydrates (NSC), and antioxidant systems.

Main Results:

• Low temperature restricts key biochemical processes essential for tree growth.
• Photosynthesis, nutrient uptake, NSC reserves, and antioxidant capacity are significantly affected.
• Understanding these mechanisms is crucial for predicting treeline responses to climate change.

Conclusions:

• Temperature is the primary factor controlling alpine treeline distribution.
• A comprehensive understanding of biochemical limitations is needed for global treeline models.
• Future research should focus on integrating these physiological insights into broader ecological frameworks.