Analysis of the Response of Coenopopulations of Vaccinium Myrtillus L. To External Impacts Using Simulation Modelling

Ground layer vegetation plays an important role in the biological cycle in forest ecosystems. However, the quantitative responses of this component to various disturbances, as well as its recovery after damage, remain poorly studied. This paper presents the results of a study of the response of bilberry (Vaccinium myrtillus L., 1753) coenopopulations to different types of disturbances. Field experiments were carried out on sampling plots in a pine forest in the Moscow region, where V. myrtillus, Convallaria majalis L. (1753), and green mosses dominated the ground layer vegetation. The experiments included three types of impact: the removal of litter, the cutting of aboveground shoots, and the cutting of rhizomes. The results showed that the survival of partial formations depends on maintaining physiological integration with the clone if shoots or rhizomes are damaged. The main recovery mechanism is the development of dormant buds on rhizomes. Removal of litter results in orthotropic growth of rhizomes and formation of new shoots. These data were used to enhance the CAMPUS‑S model with an external effects module, which was then used to simulate fires, cuttings, and combinations of these disturbances, as well as shrub regeneration after such events. Simulation experiments showed that V. myrtillus coenopopulations were resistant to one-time damage, but repeated impacts led to their degradation. Surface fires of medium intensity (affecting up to 10% of the area) did not result in population mortality, whereas 15% damage made recovery impossible. Although selective harvesting, especially with the caterpillar machinery, slowed the recovery process, it did not result in the death of V. myrtillus coenopopulations. These results can be used to evaluate the sustainability of coenopopulations and allow planning the system of forest management that minimises damage to the ground layer vegetation.