Assessment of the current state of ecosystems taking into account the diversity of adventitious species

Aim. When assessing the degree of transformation and openness of the territory for invasive species, a description of the current state of their biological diversity should be made taking into account the diversity index of adventitious species.Discussion. The problem of intensification of biological invasions has now become one of the world's most acute problems. Biological invasions of alien species have acquired such a scale that by now it is almost impossible to find terrestrial or aquatic ecosystems, wherever adventitious organisms are found. In practice, a number of categories and indices of diversity are used to assess biological diversity, and the methods of their measurement and analysis are also different. But all of them operate with almost two indicators – the number of species and their relative abundance – quantitative parameters, without taking into account modern qualitative changes in species in the composition of ecosystems.Results. It is proposed to introduce additional estimates of the share of adventitious species (the "adventiousness index") in the assessments of total biodiversity, which are necessary to solve a whole range of practical tasks. They give an idea of the state of ecosystems at the moment in a certain area, serve as the basis for the development of a management system for individual species, are necessary to assess the suitability of potential habitats for reintroduction and etc.