MINIATURA, edition 5; Grant founded by National Science Center

Dec 2021-Dec 2022

Project no: 2021/05/X/NZ8/01376

grant holder: Weronika Banaszak-Cibicka, PhD

Faunistic changes in human transformed environments are currently an extremely important and topical issue. Urban areas are increasingly seen as areas of high importance for the conservation of insect diversity and ecosystem services and therefore interest in the fauna of pollinating insects in urban areas is increasing, but our knowledge to date is still limited. Cities can provide suitable places for diverse bee assemblages, although there are also data showing a decline in bee numbers or diversity with urbanization. A better understanding of the effects of urbanization on bees is essential for the effective protection of this vital group of insects.
Despite the growing interest in the distribution of bees in cities, no research has yet been carried out on the distribution of bees in a vertical gradient. On the other hand, the few existing studies on the vertical distribution of bees in the forest environment have shown vertical stratification of bees in terms of flight altitude and use of plant resources. Across the world, canopy are home to a wide variety of invertebrate communities that are often very different from those close to the ground. Most taxa are unevenly distributed along the vertical gradient, resulting in complex vertical stratification patterns that are associated with various abiotic and biotic factors. It has been shown that this affects bees in both tropical and temperate forests, with some species more abundant in the canopy and others more concentrated near the forest floor. In this context, it is surprising that there are no similar studies in the urban environment. It can be assumed that in cities characterized by a complex vertical structure (trees, shrubs, herbaceous plants, vegetation on terraces, balconies), the vertical distribution of bees may also be significantly different. The planned research is therefore of a pioneering nature.
The aim of the planned activity is to investigate the vertical distribution of bee assemblages in an urban environment, to determine patterns for individual species, as well as to select species characteristics that may affect the distribution of bees in the vertical gradient. The research will be carried out in Poznań, on 30 research plots similar in terms of vegetation. The surfaces will be characterized, among others, by vegetation, coverage by man-made structures, the surface of green areas, distance from larger green areas, as well as the surroundings. An inventory of pollinators will be carried out from March to September. On each research plot, 6 Moericki’s traps (yellow bowls filled with water and a small amount of detergent to reduce surface tension) will be placed at three heights: two at ground level, two at a height of about 2-3 m and two at a height of 10-15 m. The insects will be removed from the traps every 7-10 days. The collected insects will be identified in the laboratory. The following will be determined: the number, species richness and diversity of the collected insects, as well as their functional characteristics. This will allow the assemblages to be assessed in terms of functional diversity indicators as well.
Understanding the distribution of bees in the vertical gradient, apart from the purely cognitive aspect, is also of great application importance in the protection of this important group of pollinating insects. Interference confined to a particular layer can affect insect assemblages along the entire vertical gradient. Knowledge of the vertical distribution of the bees will enable better planning of green spaces in cities for pollinators.