What is a grassland?
During our activities, we are at times confronted with the fact that the actual meaning of grassland is only understood by professionals (an open natural habitat with high biodiversity). In rural areas, people do not know what we are thinking about and when we make them aware of it they say “Oh, you mean the meadows? There is nothing interesting there”. In urban areas, when it comes to “grassland,” people think of a lawn, a plot of planted grass.
The connotation of grassland, from an ecological viewpoint, is a species-rich natural habitat in which herbaceous perennials are native. This kind of habitat consists usually of dozens of species of plants.
In Romania, there are two types of grasslands:
Wildlife in the Grasslands
Grasslands have diverse, and unique wildlife, due to mowing and pasturage activities, which started thousands of years ago. There are plenty of plant and animal species which are specialised on and dependent on these kinds of habitats.
Grasslands in Romania are incredibly diverse, some of them are record keepers across Europe. Some Romanian grasslands are home to more than 200 different species of plants per 100 m2, and there are plots of just 1m2 where more than 80 species coexist.
The Romanian grasslands are home to approximately a quarter of the endangered species of plants and a third of the endangered species of insects on a national level. The majority of butterfly species live here, and cannot survive without the plants specific to grasslands. The grasslands are home to a wide variety of small mammals, which on the other hand are prey animals for raptors. Even if most of our endangered raptors nest on trees, they feed mainly on grasslands, such as the Lesser Spotted Eagle. Some grassland birds not only feed but also nest in these habitats, like the Common Skylark or the endangered Corncrake.
The importance of the grasslands
The benefit of grasslands, discovered in ancient times, is the “grass” growing there, which has been exploited by humans for mowing or grazing ever since. Besides these obvious benefits, grasslands also provide several ecosystem services. Their importance as habitat for bees is highly significant, but they also provide sustenance for other insects. Their role in recreation is becoming more and more appreciated and we use it more often during the global pandemic.
In recent years, we’ve started to recognize how important they are in the fight against climate change. Their role can be divided into two parts, they are important in reducing warming due to their carbon sequestration capacity and with reducing the adverse effects of climate change they are increasing the climate resilience.
The role of grasslands in carbon sequestration to reduce greenhouse effect
Several studies argue that the carbon sequestration capacity of grasslands is similar to that of forests. Some studies have concluded that they are more resilient carbon sinks in the long run, because forests are increasingly exposed to fires due to droughts caused by climate change. For example, in recent years, forests in California have become net carbon emitters due to more frequent wildfires.
People afforested in many parts of the world without prior research for the purpose of climate protection, but most of the times they achieved exactly the opposite. For example, in Chile, forests planted to become carbon sinks do not sequester net carbon. In Hungary, forests planted on sand ridge fields induced a dangerous level of drought. In addition to this, low-lying areas are also drained, so their overall effect is not favourable at all.
More and more research proves that grasslands have a highly significant effect on greenhouse gas sequestration. We cannot tell exactly whether grasslands or forests are more important in climate change. This always depends on the particularity of the situation. However, we can claim with certainty that the protection of grassland ecosystems is essential in the fight against climate change.
This may raise the question in the reader, if grasslands are so important, why are they not better protected. Why don't we hear enough about their significance? The above-ground components of grasslands are not as spectacular or emblematic as forests. The importance of grass or a common flower is more difficult to render.
Grasslands store a significant amount of carbon below-ground in the form of humus.
Research has modelled that, as a result, their carbon storage will remain stable in the future because they are less exposed to fires and drought. This, of course, only applies to grasslands that are extensively cultivated, not overused, e.g. overgrazed.
Properly cultivated chernozem soils in temperate climate, such as grassland soils, store similar amounts of carbon dioxide to the above-ground areas of tropical rainforests. Humus can accumulate in the grassland soil because the decomposition process is much slower than in rainforests. With proper grassland management, the assimilated amount of carbon dioxide is stored for a long time.
When grasslands are overgrazed, they degrade and the carbon stored in soil is released in the air in the form of carbon dioxide.
The role of grasslands in reducing the effects of climate change
The effects of climate change are now being felt in every corner of the globe. Although in Central Europe we do not yet have such large-scale forest fires or extreme storms, we still can feel the effects of climate change. Warmer winters; wells running dry, drying agricultural lands and wildlife habitats; unequal distribution of precipitation; more frequent floods; extreme heat waves during the summer - all these factors threaten the livelihood or health of more and more people.
And even if we drastically reduce the carbon dioxide emission by miracle, these phenomena will continue to become more and more common. We must be prepared to combat the effects of climate change.
Preserving our natural ecosystems and biodiversity is essential in this context. Grasslands can also play a key role in this.
But how can grasslands protect us against the effects of climate change, or in other words, how do they increase climate resilience?
Grasslands are important bases for water conservation. Due to rich soil, and roots they are able to absorb large amounts of precipitation. Subsequently, the water is retained, does not flow away, and evaporates much slower in comparison to arable land or urbanized areas. The water in the soil also increases the water content of the subsoil, thus among other things it reduces the risk that wells are running dry. An additional benefit of their water retention capacity is slow drainage, thus water does not wash away the soil and due to this it also contributes to the diminution of soil erosion.
Preserving biodiversity is essential in the fight against climate change. Nothing can reduce either global warming or the effects of climate change better than a healthy ecosystem. Grasslands play a key role in maintaining the balance of our ecosystem because, as mentioned in the introductory part, many species live in grasslands or depend on them in some way. For example, most forest species also rely on grasslands in some form.
While joining the European Union, Romania agreed to maintain its grasslands. Nevertheless, we have been losing them further over the last decade and a half, mainly due to turning them into arable lands. Furthermore, due to degradation and overgrazing, many grasslands are unable to fulfil their ecological role.
Preserving the grasslands is our common interest. Even though grasslands are not as spectacular as forests, their role in climate protection is equally important.