Semi-natural grasslands are open habitats where farming has occurred at a low intensity. These areas remain open because of regular mowing, grazing or burning. Otherwise they are largely unaltered, with little use of artificial fertilisers and herbicides.
Across Europe, many meadows have been cut for winter hay or grazed by small herds of sheep or cattle for centuries. This continuity of traditional management has allowed grasslands to accumulate a large number of specialised species. As such, semi-natural grasslands are biodiversity hotspots. They support plants, insects and birds which are rarely found in other habitats. Due to their history, grasslands are also an important element in cultural landscapes and often have a great deal of touristic and heritage value.
Despite this, recent years have seen a decline in the number and size of grassland habitats. Since the beginning of the 20th Century, large areas have been converted to agricultural fields or forest plantations. As a result, many landscapes have lost up to 90% of their original semi-natural grassland. This loss of habitat threatens vulnerable species. As a result, the protection of remaining grassland diversity is a conservation priority.
Across Europe, many meadows have been cut for winter hay or grazed by small herds of sheep or cattle for centuries. This continuity of traditional management has allowed grasslands to accumulate a large number of specialised species. As such, semi-natural grasslands are biodiversity hotspots. They support plants, insects and birds which are rarely found in other habitats. Due to their history, grasslands are also an important element in cultural landscapes and often have a great deal of touristic and heritage value.
Despite this, recent years have seen a decline in the number and size of grassland habitats. Since the beginning of the 20th Century, large areas have been converted to agricultural fields or forest plantations. As a result, many landscapes have lost up to 90% of their original semi-natural grassland. This loss of habitat threatens vulnerable species. As a result, the protection of remaining grassland diversity is a conservation priority.
What is functional connectivity and why is it important?
For plants, the functional connectivity of a landscape is a measure of species' ability to move seeds and pollen between areas of suitable habitat. As the amount of habitat declines, plant populations become smaller and more isolated. This means dispersing seeds and pollen are less likely to reach these areas. Links between habitat areas are lost, reducing functional connectivity. The loss of other animals or activities that transfer plant material between habitats can have a similar effect.
Species with low functional connectivity are more likely to become locally extinct within landscapes. This is because there is less chance of new individuals arriving, either to rescue threatened populations or to re-colonise previously occupied areas. Less movement between habitats also reduces genetic diversity. Small, isolated populations become more inbred as they are not able to exchange genetic material with neighbouring habitats. This reduces species' ability to adapt to environmental change, and so also increases their risk of extinction.
As a result, reductions in connectivity are associated with a loss of species diversity within landscapes. Numerous conservation schemes aim to address this by increasing functional connectivity, but doing this effectively requires a clear understanding of the various processes involved.
Species with low functional connectivity are more likely to become locally extinct within landscapes. This is because there is less chance of new individuals arriving, either to rescue threatened populations or to re-colonise previously occupied areas. Less movement between habitats also reduces genetic diversity. Small, isolated populations become more inbred as they are not able to exchange genetic material with neighbouring habitats. This reduces species' ability to adapt to environmental change, and so also increases their risk of extinction.
As a result, reductions in connectivity are associated with a loss of species diversity within landscapes. Numerous conservation schemes aim to address this by increasing functional connectivity, but doing this effectively requires a clear understanding of the various processes involved.
What helps species disperse?
Windblown seeds are able to reach other nearby habitat, but this is only rarely useful for travelling longer distances. Corridors of suitable habitat within the landscape can act as stepping stones, allowing species to move further via a series of smaller jumps.
Attempts to increase green infrastructure often focus on increasing the number of these links by creating new habitat or improving the quality of existing areas. For grassland plants these can be restored semi-natural grasslands, or other smaller habitats such as road verges, hedgerows and forest borders.
Some seeds have structures which allow them to attach to the fur of grazers as they brush past. Others are adapted to survive being eaten and then passing through an animal's digestive system. This means that managing the movement of livestock between grasslands is another way of increasing functional connectivity. This can help species to reach isolated sites which would otherwise be inaccessible. However, to be successful plants must also be able to establish themselves in the new location.
Attempts to increase green infrastructure often focus on increasing the number of these links by creating new habitat or improving the quality of existing areas. For grassland plants these can be restored semi-natural grasslands, or other smaller habitats such as road verges, hedgerows and forest borders.
Some seeds have structures which allow them to attach to the fur of grazers as they brush past. Others are adapted to survive being eaten and then passing through an animal's digestive system. This means that managing the movement of livestock between grasslands is another way of increasing functional connectivity. This can help species to reach isolated sites which would otherwise be inaccessible. However, to be successful plants must also be able to establish themselves in the new location.
Project aims
We will investigate how different aspects of functional connectivity interact within landscapes to influence plant species diversity. Also, how this contributes to other services provided by semi-natural grasslands, such as pollinators for surrounding cropland, carbon storage and the aesthetic and recreational value of the landscape.
In order to achieve this, we will measure current levels of green infrastructure and functional connectivity in grassland landscapes across Europe, as well as how much this has changed in the past. The effects of this on plant dispersal and diversity will be measured in a number of ways.
From this, we aim to determine the plants likely to benefit most from enhanced green infrastructure and improved functional connectivity. Understanding how landscape structure, plant ecology and human management combine to affect dispersal patterns will help create effective measures to conserve important semi-natural grasslands.
In order to achieve this, we will measure current levels of green infrastructure and functional connectivity in grassland landscapes across Europe, as well as how much this has changed in the past. The effects of this on plant dispersal and diversity will be measured in a number of ways.
From this, we aim to determine the plants likely to benefit most from enhanced green infrastructure and improved functional connectivity. Understanding how landscape structure, plant ecology and human management combine to affect dispersal patterns will help create effective measures to conserve important semi-natural grasslands.