Invasive alien woody plants: Are they such a big problem?
There has been a lot of discussion about the overgrowth of invasive alien plants in recent years. This is a problem that affects the entire world. Fighting against them has cost 1.3 billion dollars between 1970 and 2017[1]. These plants disrupt the stability of ecosystems, cause economic damage and in some cases, lead to the extinction of species. While many publications focus on invasive plants, very few of them study invasive woody plants and their impact on the environment, ecosystems, or soil[2,3]. Our project (GACR Impact of alien and native woody plants on vegetation and soil: two sides of the same coin?) aims to fill this gap because tree species are crucial ecosystem engineers. They impact soil and light conditions, provide habitats for birds and insects, and produce wood for human use.
I work on this project with my colleagues from the Department of Invasion Ecology at the Institute of Botany, Academy of Sciences of the Czech Republic. We also cooperate with scientists from Poland and Slovakia. The main goals are to study the impact of invasive woody plants in comparison with native expansive species and to study the impact on different levels, chemist of soil, abiotic factors (such as light, microclimate) and vegetation.
We began the work on this project last year. During the summer season, we started vegetation mapping of research areas with invasive woody plants, native expansive species, and controls. This data can help us study the actual impact of these species and make decisions about protecting nature.
Then during the autumn, we started working on soil analyses. Now comes the funny part of our job! We had to collect coloured leaves from the ground and also from the trees for decomposition analysis. First, we dried them, then we weighed 5 g of leaves of dominant species and control, put them in decomposition bags and buried them. With this experiment, we want to study whether there is a difference in decomposition between invasive woody plants and native dominant species, or if it varies between species or locations. We have several hypotheses, and this experiment will help us better understand the impact of different factors on decomposition. To study nutrient availability in the soil, we use PRS ion exchange probes. Their membranes work like roots and catch anions and cations from the soil. It can help us understand, for example, which nutrients from soil are available for plants and which are not.
We will see next year, which hypotheses were correct and which not :)
References
1. Finanční dopady invazních nepůvodních druhů: [cited 5 Jan 2024]. Available: https://www.casopis.ochranaprirody.cz/mezinarodni-ochrana-prirody/financni-dopady-invaznich-nepuvodnich-druhu/
2. Pyšek P, Bacher S, Kühn I, Novoa A, Catford JA, Hulme PE, et al. MAcroecological Framework for Invasive Aliens (MAFIA): disentangling large-scale context dependence in biological invasions. NB. 2020;62: 407–461. doi:10.3897/neobiota.62.52787
3. Pyšek P, Hulme PE, Simberloff D, Bacher S, Blackburn TM, Carlton JT, et al. Scientists’ warning on invasive alien species. Biological Reviews. 2020;95: 1511–1534. doi:10.1111/brv.12627
