Morphological variability of the rare species Linaria cretacea in the conditions of the chalk hills in North-Western Kazakhstan

Morphometric techniques are crucial when studying rare plant species as they provide a comprehensive dataset on individual plants and the status of specific populations under various ecological conditions and different levels of human impact. Linaria cretacea, an endemic plant species, is listed as rare and can be found exclusively in the chalk hills in North-Western Kazakhstan (NWK). Over the span of 2020 to 2022, we conducted a study on four populations of this species located in the chalk hills in NWK. Through the process of inventorying sampling plots, we assessed the elevation range occupied by the species, while also identifying the age structure and population density. The results of our study provided further evidence of the limited population counts of Linaria cretacea, as reported previously. Additionally, we conducted an investigation into the biometric traits of virgin and generative Linaria cretacea individuals across different populations, including an analysis of their seed parameters. The morphometric parameters exhibited notable variations among the populations under investigation, with the exception of the seed measurements, which showed minimal to negligible variability. The species’ coenopopulations are currently in a stable state, but the absence of adequate protection measures is a cause for concern. Therefore, it is crucial to undertake regular monitoring of their habitats and enhance environmental measures to safeguard their well-being.