DISTRIBUTION MODELS, CLIMATIC CHANGES AND POTENTIAL EFFECTS ON SPECIES

The study of ecological niche occupied by each species in the different ecosystems is an integral part of the distribution of living organisms. The complex of bioclimatic, botanical and eco-physiological characteristics represents the realized niche of a certain species. This concept is at the bottom of the development of predictive models on species distribution and on relative changes due to global warming. The response of certain fitness-related reaction norms for organisms under ‘unusual’ climatic circumstances was demonstrated to be curvilinear rather than linear, hence being less predictable than a linear response. Unusual climatic circumstances are predicted to increase in frequency during the next decades under global warming scenarios, hence predictions on the potential effects of climate change on biodiversity based on linear models are clearly not plausible and excessive from a mathematical point of view. Therefore, when developing predicting models is better to consider the maximum number of variability factors in order to weigh out the contribution of each of these to the studied phenomenon.