Raunkiääriien

Raunkiääriien, also known as Raunkiær plant life-forms, are a system for classifying plants based on their perennating (surviving) buds or shoots. Developed by Danish botanist Christen Raunkiær in the early 20th century, this classification aims to relate plant form to climate. The system categorizes plants into major groups, or life-forms, based on the position of their perennating organs relative to the ground and their protection during unfavorable seasons.

The primary life-forms include phanerophytes (trees and shrubs with buds well above the ground), chamaephytes (shrubs and herbs with buds on low stems), hemicryptophytes (herbaceous plants with buds at or just below the surface), cryptophytes (plants with buds underground or underwater, further divided into geophytes and helophytes), and therophytes (annuals that survive unfavorable periods as seeds). Each life-form is often associated with specific climatic conditions, with phanerophytes dominating tropical and temperate forests, and hemicryptophytes and therophytes common in colder or drier climates.

The Raunkiær system provides a valuable tool for ecological studies, allowing scientists to compare vegetation across different regions and infer climatic conditions based on the dominant life-forms present. While it has been refined and supplemented by other classification systems, the core principles of Raunkiær's life-form categorization remain influential in understanding plant adaptation and distribution.