How can plants safeguard our future?
Those of us with green thumbs work hard to create the best possible living conditions for our plants. Soil, temperature, water, and light need to work in harmony for a plant to thrive. There are plants, however, that take matters into their own hands, and shape their environment to their liking. How do these ecosystem engineers build their own habitats, from the sea to the mountain? And what can we learn from them to keep our own habitat safe? We talked to three researchers who study three different ecosystem engineers – Paul Berghuis studies dune grasses, Ralph Temmink peat mosses, and Jana Eichel alpine shrubs – to find out.
Paul Berghuis – Dune grasses
How does your plant engineer its habitat?
Marram grass, Calamagrostis arenaria, like other dune building plants, is an architect of coastal dunes. When they colonise a bare beach, grass shoots slow down the wind and airborne sand gets trapped in their canopy. As this sand starts to accumulate, the grasses are slowly buried. Instead of suffocating, they respond by growing faster and pushing new shoots up through the sand. More growth means a denser canopy, which traps even more sand. This feedback between plant growth and sand trapping builds a small dune around each plant. While initially these dunes are small, the combined sand trapping capacity of all dune grasses together accumulates over time and can transform a flat beach into an elevated dune landscape within just a decade.
How do we benefit from this?
By building dunes, marram grass creates the very landform it depends on. On top of a dune, the grass escapes flooding, salt spray and drought of the exposed beach. The dunes also provide important ecosystem services – how humans directly and indirectly benefit from nature. Coastal dunes form a natural barrier that protects the low-lying land behind them from storms and flooding. Rain that falls on the dunes filters through the sand and collects underground as a large freshwater reservoir, which is used for drinking water. Dune-building grasses therefore help us to secure coastal safety as well as fresh water supply.
Few countries in the world depend as heavily on coastal dunes for flood protection as the Netherlands.
What can we learn from your plant?
Marram grass is an exceptional dune builder. Each plant adjusts its growth to capture as much sand as possible, and many patches of this dune grass together can achieve even more. My research shows that the way grass patches are arranged in space shapes how dune landscapes form and how they respond to disturbances. People have planted marram grass to strengthen dunes for centuries, but we have paid too little attention to how these grass species naturally organise themselves. By investigating these natural spatial patterns, we can learn from them and improve the way we build and restore dunes.
Ralph Temmink – Peat mosses
How does your plant engineer its habitat?
Peat mosses or Sphagnum are small mosses that shape whole bog landscapes in cool regions. They act like sponges, holding large amounts of water and keeping the ground wet. They also make the water acidic, which slows the decay of dead plants. Over hundreds or thousands of years, this partly decayed plant material builds up as peat. Wet and acidic conditions help peat moss thrive while making it harder for many other plants to grow. In turn, more peat moss holds more water and maintains the bog. This feedback slowly builds deep peat layers over thousands of hectares and creates the distinctive bog habitat we see today.
How do we benefit from this?
Peatlands are world’s carbon densest ecosystem and store more carbon than tropical rainforests. Waterlogged plant material decomposes very slowly and helps to limit the release of carbon dioxide to the atmosphere. Bogs also act like natural sponges: they absorb rainfall, release water gradually, and can reduce flood risk downstream. In addition, they filter water, support specialised plants like carnivorous sundew and animals like the iconic crane, and preserve long-term records of past climates and landscapes within their peat layers. Protecting bogs therefore helps protect biodiversity, water resources, and the global climate.
Peatlands must be rewetted to keep carbon locked in its natural vault, to stop land subsidence, and allow the formation of new peat.
What can we learn from your plant?
We destroyed most of our natural peatlands in the Netherlands. Restoration should first restore the basic conditions needed for peat moss to survive. This means rewetting drained peat by blocking drainage channels and raising water levels. Once the peat is wet again, restoration should harness the natural processes through which peat moss improves its own habitat. Peat moss holds water, keeps the ground wet, and slows the decay of dead plants. These processes help the moss expand and allow peat to form again.
Jana Eichel – Alpine plants
How does your plant engineer its habitat?
All alpine plants above the tree line are adapted to their harsh environment, but some of them also shape it. The prostrate shrub Mountain Avens or Dryas octopetala, grows on slopes where wind, water, gravity and freeze-thaw cycles move soil and rocks. Its dense stems and leaves slow wind and flowing water, allowing fine sediment to settle around the plant. Its strong root systems adapt to creeping soils by growing upslope, making the plant act like an anchor. Dead plant material accumulates beneath the canopy, insulating the soil and adding organic matter that supports soil development. These changes create more stable, nutrient-rich patches that can later be colonised by other plants and soil organisms.
How do we benefit from this?
By slowing the movement of soil and water, alpine engineer plants can reduce erosion and help stabilise mountain slopes. But that’s not all. We think that their effects on soil movement can initiate the formation of drop-shaped landforms called solifluction lobes, developing as soil slowly moves downhill through repeated freezing and thawing. These widespread landforms are more than just features of the landscape: they form diverse habitats for plants, animals and microorganisms, while also storing carbon, water and nutrients. In this way, a small plant can influence the shape of the landscape and the services it provides to the wider ecosystem.
Fun fact: Alpine ecosystem engineers shaped Dutch and Central European hillslopes 12000 years ago during the ‘Younger Dryas’ period – named after alpine engineer shrub Dryas octopetala.
What can we learn from your plant?
Alpine plants are strong. They not only survive on slopes with moving soils but actively stabilise them. Recently identified alpine engineer species could potentially be used for erosion protection, strengthening nature-based solutions. This leads to my next research question for cold, steep hillslopes: if plants can engineer their surroundings successfully in nature, can we encourage them to do the same for us where erosion protection is needed? In other words, can we harness the power of alpine plants for nature restoration and conservation?