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The dreams of Humboldt and many of his successors have not yet come true. Despite the great achievements of the last century, we still do not know the total number of vegetation types or the difference in the patterns of the distribution of diversity above and below the ground, we cannot predict all the effects of climate change on vegetation at the regional and global scale, we do not know the hidden and dark parts of species diversity in most ecosystems, nor are we able to make historical vegetation maps for many areas of the Earth. We also do not know the cultural contribution of many plant communities for the development of human populations and civilization, nor do we know the future recreational and therapeutical potential of vegetation (e.g., aromatherapy, ecotherapy). Geobotanical methods can effectively contribute to finding the answers to hot questions in current ecology. Since there are so many gaps in our geobotanical knowledge and so many young researchers still speechless with delight when looking at endless steppes, lush rainforests, tall-herbs, or colorful meadows, there is no doubt that geobotany will be a thriving and developing discipline in the future. Its driving force is the passion of researchers and admiration for the beauty of various types of vegetation and their dynamics as well as awareness of the need to protect them for generations to come.

The uneven presence of the cork oak (Quercus suber L.) within its distribution range is not only determined by its climatic requirements but also by specific edaphic needs. Although most of the natural populations thrive in acidic soils deriving from metamorphic or volcanic rock outcrops, some cork oak populations are found growing in soils deriving from calcareous bedrock, which are considered less suitable. We carried out a multidisciplinary investigation at the south eastern edge of the Q. suber distribution range (Mountains of Palermo, NW Sicily), including soil, floristic, and vegetation surveys, aimed at: (i) assessing the native or introduced origin of some peculiar cork oak populations; (ii) describing the associated plant communities and soils; (iii) identifying the ecological factors which could explain the local adaptation to soils deriving from calcareous bedrock; (iv) discussing the ecological role played by this species in the study area and within its distribution range. The collected information suggest that the detected cork oak stands are native to these areas. We hypothesized that the co-occurrence of high fire frequency, high soil calcium content and erosion, which caused the intermixing of different parent materials, might favor its competitive interactions with other Mediterranean tree species, thus accounting for the local presence of Q. suber. The study of cork oak populations thriving in peculiar substrates at the driest end of the range could be of great importance for the future conservation of this species, which is expected to face growing threats in the coming decades.

Organisms with different life histories are able to act as indicators of different characteristics of their environment. Here, we compared the precision of habitat indication by the vegetation and soil microbial communities in four salt-affected pastures: annual open salt sward, Pannonic Puccinellia limosa hollow, Artemisia saline puszta and grassy saline puszta. Dissimilarity of habitats was evaluated by standardized principal component analysis (PCA) based on four different datasets: catabolic profiles of microbial communities in June (a) and September (b), composition of vascular vegetation (c) and physical and chemical properties of the soil (d). Procrustes analysis was used to quantify the resemblance between pairs of PCA ordinations based on soil properties (d) and various biotic communities (a, b, c). PCA ordination based on vegetation most closely matched the soil data-based ordination, thus vegetation appears to better indicate habitat conditions than soil microbial communities do. For microbial communities, a better agreement with the soil data-based ordination was reached in September than in June. Most probably, the long-lived sedentary habit of perennial plants in these communities requires adaptation to long-term average habitat conditions. In contrast, short-lived soil microbes can quickly follow environmental changes, thus the composition of soil microbial communities better reflect actual soil conditions.