Pioneer species
Definition
Pioneer Species are a group of species that are the first to colonize a new habitat created by a previous disturbance. These disturbances could be a fire, flood, or volcanic activity that causes very fine or non-existent soil, high heat, or lack of water.
Ecological Succession
Ecological succession is the process that allows pioneer species to become apparent in disturbed habitats. This is a change in structure that occurs within a community or ecosystem and has multiple phases dependent on different patterns of regrowth within an ecosystem. Ecosystems advance until they reach a climax community, where all of the resources are efficiently used and the total mass of vegetation reaches a peak. The concept of ecological succession has two types: primary succession and secondary succession. Primary succession is when soils are not yet formed in an area, preventing new vegetative establishment. Over time, small organisms and erosion break down these rocks into soils allowing for the introduction of pioneer species into the area. More often, pioneer species are brought about through secondary succession, a process that, as long as the soil is not destroyed within a natural disaster-affected ecosystem, can flourish with pioneer species. [2]
[2]
Pioneer Flora
Flora are the first to become pioneer species across all types of natural disaster sites. Due to a lack of nutrients in the soil, most pioneer species have to be hardy plants with adaptations such as long roots and the ability to live in harsh conditions with a lack of water and sunlight. The seeds also have to be able to germinate easily, allowing species to propagate even after years of dormancy and be able to disperse via wind. This is due to the lack of other forms of dispersal like fauna distribution. The propagule size of the seeds must also be small due to the realization of succession goals and the ability to disperse seeds within small crevices surrounding the habitat. Their lifecycles must also be short as pioneer species cannot stay in one place with little to no nutrients for long. [3]
These species are needed in order to develop and reform ecosystems, allowing for development in a nutrient-poor environment.
Examples of Pioneering plant species:
- Lichen: A fungus and an alga typically found on rocks and shady places
- Moss: Non-vascular plants that form dense green clumps in damp and shady areas
- Grass: Small-seeded blades of plant that grow in crevices
Pioneer Fauna
While pioneer fauna is harder to find and typically does not appear until the pioneer flora has first established an area, there are still some species that are more so present in the early stages of disaster-struck areas. Some examples of pioneer fauna are soil invertebrates like worms, ants, snails, and possibly even some toads. These species are important to the soil of the area, as they both help the pioneer flora to flourish but also bring nutrients back into the soil that it was once lacking. Once the introduction of pioneer fauna is present, the area will continue to advance at a rapid pace and more species will start to migrate towards the ecosystem [3].
References
[1] Sataksig. (2019, February 3). Pioneer plants: What is it, and what does it do? Earth Buddies. Retrieved April 20, 2022, from https://earthbuddies.net/pioneer-plants/
[2] Editors, B. D., (2019, October 5). Ecological succession - definition, examples and types. Biology Dictionary. Retrieved April 20, 2022, from https://biologydictionary.net/ecological-succession/
[3] Pioneer species - definition and examples - biology online dictionary. Biology Articles, Tutorials & Dictionary Online. (2022, January 13). Retrieved April 21, 2022, from https://www.biologyonline.com/dictionary/pioneer-species
[4] Dalling, J. W. (2008, January 1). Pioneer species. University of Illinois Urbana-Champaign. Retrieved April 21, 2022, from https://experts.illinois.edu/en/publications/pioneer-species
[5] Futura-Sciences. (n.d.). Pioneer species. Futura. Retrieved April 21, 2022, from http://www.futura-sciences.us/dico/d/botany-pioneer-species-50002180/