SIZE AND VITALITY CHARACTERISTICS OF STELLARIA HOLOSTEA L. PLANTS AND POPULATIONS IN DESNIANSKO-STAROHUTSKYI NATIONAL NATURE PARK

The study of coenotic species in forest herb layers enables detection of ecosystem-level changes, with research in protected areas providing a foundation for long-term monitoring. This study assessed Stellaria holostea L. populations in forest phytocoenoses of Desniansko-Starohutskyi National Nature Park, typical of the Sumy Polissia region. Populations were surveyed in various forest types: Pinetum (sylvestris) convallarioso (majalis) � hylocomiosum, Pinetum (sylvestris) vaccinioso (myrtilli) � moliniosum (caeruleae), Pinetum (sylvestris) vaccinioso (myrtilli) � sphagnosum, Betuletum (pendulae) caricosum (pilosae), and Quercetum (roboris) convallariosum (majalis). Morphometric analysis of plant size traits and vitality assessments, following Yu. A. Zlobin�s method, enabled classification of populations as depressive, balanced, or thriving. Ecological indicators from Y. P. Didukh�s scales provided insight into edaphotope and climatotope influences. Statistical analysis revealed significant morphometric variability across phytocoenoses, and model plants were developed for each type. Vitality levels were categorized into three classes (a, b, and c), with quality index (Q) values ranging from 0.10 to 0.48. Depressive populations were found in Pinetum (sylvestris) convallarioso (majalis) � hylocomiosum and Betuletum (pendulae) caricosum (pilosae), balanced in Pinetum (sylvestris) vaccinioso (myrtilli) � sphagnosum, and thriving in Pinetum (sylvestris) vaccinioso (myrtilli) � moliniosum (caeruleae) and Quercetum (roboris) convallariosum (majalis). Findings indicate a strong response to soil moisture and fertility, with inter-factor interactions significantly impacting plant characteristics. These results underscore the effectiveness of using size and vitality traits in long-term monitoring of Stellaria holostea populations.