Pioneer species are very important in ecosystem restoration, land improvement, rewilding, and the establishment of sustainable food producing systems. But what are pioneer species, and how are they used? Read on to find out more.
What are Pioneer Species?
Pioneer species are essentially plant species which are particularly efficient and effective when it comes to colonising an area of land. They are typically native plants, which are utilised to recover and reclaim areas which have become degraded by climate change or human activity.
These trees or other plants, which thrive in a particular ecosystem or environment, can be beneficial in a wide range of different ways. They provide crucial ecosystem services which allow other plants – and often people too – to thrive. By establishing pioneer species first on troublesome sites, it is possible to dramatically improve conditions, and considerably extend the range of other plants which are then able to grow.
What Pioneer Species Do and How They Are Used
In order to understand pioneer species a little better, let’s take a look at what some key pioneer species do, what they can provide, and the reasons, therefore, for which they are used. Understanding the why and how can help us use pioneer plants to achieve the ecosystem results we are looking for.
Pioneer Species for Nitrogen Fixation
One of the key services pioneer species can provide is nitrogen fixation. Many pioneer plants are what are called nitrogen fixers. These plants form symbiotic relationships with certain bacteria in their root nodules which take atmospheric nitrogen from the air. This nitrogen is made available for the use of the plant itself, but also add nitrogen (to varying degrees) in the surrounding soil.
Nitrogen fixing trees and shrubs are often particularly useful pioneer species. Through fixing nitrogen, they can improve the fertility of the soil in a degraded or depleted landscape. And through increasing soil nitrogen, can then allow a wider range of other plants to grow.
Over time, these nitrogen fixing species can be coppiced, or chopped and dropped, to feed and improve the soil. And may, over time, be shaded out or outcompeted by other species as the soil and conditions on a site begin to improve.
Pioneer Species for The Water Cycle
Since many pioneer species are drought tolerant, and able to survive in less than optimal conditions, they can therefore be used in the restoration of watersheds. Using pioneer plants to revegetate degraded watersheds can play a key role in protecting and restoring the world’s water cycle.
Native, drought tolerant plants can pave the way for re-greening – even in desert regions and other unpromising arid spaces. On a small scale, they can help keep water in a landscape. On a larger scale, they can actually increase the rainfall in a region.
Pioneer Species for Soil Stabilisation
Many pioneer species can also be chosen to improve soil conditions on a site in other ways. Deep rooted pioneer plants, for example, can be very useful for soil stabilisation. These deep rooted, resilient plants can be key in revegetation efforts. They can help in preventing soil erosion and run off, and be used to secure soil on slopes.
Often, these deep rooted pioneer species can also become a key part of a scheme designed to maximise carbon sequestration. By storing carbon in their extensive root systems, they not only improve aeration and protect the soil ecosystem, but also aid in our fight against our climate crisis. Deep rooted pioneer plants can often survive where other plants may struggle to become established – such as areas with low water availability, areas where wind rock can be a problem, or areas with lower topsoil fertility.
Pioneer Species To Generate Organic Matter
Some pioneer species are also chosen for their fast growth. Quick growing pioneer species quickly generate a lot of biomass – organic matter which can go into improving the soil on the site. Fast growing pioneer species will provide materials which will allow the rest of the design for a site to be created without recourse to external materials – often in addition to providing one or more of the other services described in this article.
Fast growing deciduous species will naturally enrich the soil when their leaves fall or they die back in the winter months.
But those involved in land restoration may also coppice or manage the material to improve the soil too. Whether they are shorter-lived species which are removed, or outcompeted as the system evolves. Or species which remain as part of a system over time. They can be useful additions to an ecological system and will help you achieve a closed-loop, self-reliant system over time.
Pioneer Species For Wind Mediation
Resilient pioneer species can also be very useful in their ability to withstand more challenging environmental conditions. Species which can withstand an exposed and windy location, for example, can be used to improve environmental conditions before other plants are placed. They can be used to make a wind break hedgerow, or shelter belt planting.
These techniques can mediate the wind on a site, and once established, will make it easier to create a richer and more biodiverse planting scheme.
Pioneer Species for Shade
One final service which pioneer species can provide is shading. Pioneer trees and shrubs can be used to increase canopy cover and increase shade. A higher level of shade on a site can be beneficial because it can reduce temperatures, reduce water loss from plants and the soil, and create more diverse environmental conditions for diverse and useful planting.
Choosing Pioneer Species
One important thing to remember when choosing pioneer species for a site is that what works well in one particular location will not necessarily work well in another. While there are pioneer species suited to any site, anywhere in the world – it is important to select the right plants for the right places.
There are many pioneer species to consider for any location. And a good place to begin is with plants which are native to your area. Native plants are often the best adapted to your region, and to the conditions which are found there, and will therefore most effectively provide the services described above.
Careful consideration of pioneer species is crucial to reclaiming and restoring any piece of land – especially those in more challenging environmental conditions. Where pioneers lead the way – other productive plants can follow for the enrichment of natural ecosystems, and the improvement of human lives through abundant and biodiverse food producing systems or rewilded areas which can provide a range of ecosystem services.
