Green Lawn as an Ecological Phenomenon

BY
James
/
/
in
sustainable

Globalization is driving the worldwide homogenization of urban landscapes. One of the most powerful symbols of modern urban landscapes is the lawn. There are just a few management options for urban lawns, regardless of how they are used and where in the city they are situated. 

Today, lawns occupy much of the green open spaces in cities and are located in private front and rear gardens, public parks, cemeteries, golf courses, and along roads. 

Lawns are widely advertised by urban planners, landscape architects, developers, and mass media as a very useful consumer product for the market. We regard lawns as specially constructed plant communities with the domination of a limited number of grass and herbaceous species which are densely planted and depend on a special management regime (regular mowing). The lawn is designed for social (sport and recreation), historical, aesthetical, and cultural purposes (viewing, picnicking, playing golf, football, and walking). 

There are intensively managed lawns (frequently cut short) which we call “conventional” and less-frequently cut lawns which are “meadow-like lawns.

If fertilizers, pesticides, and herbicides are used, the surrounding surface water and groundwater may be affected. Bolund and Hunhammar (1999) present six major groups of 66

important urban ecosystem services: air filtering, micro-climate regulation, noise reduction, rainwater drainage, sewage treatment, and recreational/cultural values. Out of these six, the one where lawns are most important is rainwater drainage. In vegetation-free cities, the rainwater ends up as surface runoff. In areas with a permeable surface, such as a lawn, only 5-15% of the rainwater becomes surface runoff, whereas the rest evaporates.

Lawns cover large areas of public courtyards, parks, golf courses, sports fields, and traffic environments.

Like everywhere else in the Western world, lawns in Sweden are widely advertised by urban planners, landscape architects, developers, and mass media as a very useful consumer product for the market. 

Biodiversity and environmental impact

The biodiversity and environmental impacts of differently managed lawns being studied are species diversity and composition of plants, bees, butterflies, and earthworms, energy use, and carbon footprint. Carbon sequestration is being modeled, as is the balance between sequestration and emission of greenhouse gases (GHG), including hidden carbon costs (GHG emissions associated with the production of mineral fertilizers, pesticides, mowing, etc.) in the different lawn types

Global lawns Today, one of the most prevalent, influential, and visible elements within all types of urban GI is the lawn. It is also the most powerful symbol of modern urban global landscapes. The lawn prototype is probably the European floodplain meadow vegetation and secondary meadows after clearing and grazing. In Mediaeval times, the lawn was used as a decorative element for the first time. It was mostly cut turf from meadows which were transported to castle gardens. The lawn was an essential element of English landscape parks of the 18th century and an important part of the Gardenesque parks of the 19th century. From this time the lawn became the symbol of social status. The decorative grass was used for pleasure and recreation rather than as a  productive landscape for grazing. During the 20th century, the desire for lawns created a commercial multi-billion industry to produce seeds, pesticides, fertilizers, irrigation technology, and lawnmowers. The most common and positive perception of lawns is their recreational value, such as inaccessible park playgrounds, private garden lawns, golf courses, and sports fields. On the other hand lawn’s intensive management and maintenance at the present status (frequent mowing, application of herbicides and fertilizers, using certain types of mowers and chemical products) has a significant negative impact on the environment, biodiversity, and human health

Green walls and green roofs

Given the constant growth and densification of cities, there is a need to consider also other dimensions of green in addition to green areas on the ground such as green roofs and walls (vertical gardens) for the GI of future cities. However, very little research has been done in Europe to study the contribution of these elements to biodiversity and ecosystem services such as noise reduction, pollination, health promotion, or food production. The commercialization of green roof technologies and mass production lead to the homogenization of these elements as well.

Green areas in cities are valuable for many reasons, e.g., as places for people to meet, as memorial parks or sports fields, and as habitats for many other species. They can improve the urban environment, e.g., by contributing to carbon sequestration, water infiltration and noise reduction, and access to green areas important to people’s health. Because of their dominance of urban green areas, lawns, more than any other vegetation, provide most citizens with their daily contact with nature, which in turn greatly influences their understanding of nature. To be able to promote the generation of ecosystem services provided by lawns, today and in the future, it is crucial to understand how their present planning and management affect different services. This is particularly so in times when cities are constantly growing at the expense of urban green areas. The biodiverse style benefits the environment and economy by creating jobs and providing food security through urban edible plant growth. The next generation of lawns, green roofs, and green walls will be an important part of sustainable urban living, not just sustainable green infrastructure.

To create sustainable urban green spaces, consider a new landscape architecture style that's different from the typical picturesque-garden approach. Since lawns are covering up to 70% of green areas in cities we see this type as one of the most important objects for future research together with the other two structural spatial elements –green roofs and green walls. Among the major tasks should be an evaluation of environmental services provided by these elements of green infrastructure, its contribution to biodiversity loss, influence on the hydrological urban cycle, and effects according to water prices and economic costs.

The ecological and environmental benefits of lawns are huge. Especially considering that many of us nowadays live in highly populated suburban areas where there seem to be more concrete and pavers than green grass…

Deep-rooted, dense, and hardy grass varieties can help prevent soil erosion due to rain or wind, as their roots intercept raindrops before they work down into the soil, and hold firm in strong winds. This is especially important if your home is set on a sloping block.

A healthy lawn acts as an air filter, trapping and absorbing smoke, dust, and pollutants that would otherwise be breathed in by us.  Grass absorbs carbon dioxide and other dangerous atmospheric pollutants, thereby effectively creating a cleaner, greener environment.

We all know how concrete and metal surfaces reflect noise.  And for those of us who live in the cities, this is a genuine and growing concern. Turf, by comparison, absorbs noise – just another reason why a healthy, happy lawn is essential for our physical well-being.  

Turf cools itself and the air around it in hot weather, using the simple process of evaporation.  By comparison, surfaces such as concrete and asphalt, when subjected to the hot summer sun, can heat up to a point where they are dangerous to walk on. Planting a lawn area around your home may dramatically help with climate control inside the home. Especially at night when other surfaces are still radiating heat long after the sun has gone down.

Water that is filtered through a system of healthy soil and grassroots is a much cleaner product to return to nature.  Much of the contamination is removed by the grass, and the acidity level of the groundwater is greatly reduced.  Because water runoff is generally fed back into our lakes and waterways, it must be as clean as possible.

 

 

 

Purify and Improves Air Quality

Grass takes up carbon dioxide and releases oxygen like all living plants. It doesn’t only remove carbon dioxide from the atmosphere, but it also traps dust to keep it out of both the air and your lungs. The grass is responsible for trapping 12 million tons of dust each year that would otherwise contaminate the air. Less dust blowing around means easier breathing. It also means cleaner cars, cleaner houses, and cleaner windows.

Improves Water Quality and Prevents Erosion

The soil provides nutrients while the root system of grass provides stability for the soil. Grasses help reduce erosion caused by wind and rain – thanks to this root system. Grasses have a dense network of roots that help trap and remove pollutants from the water as it moves through the soil. Compacted soil doesn’t allow water to sink into it. It means that groundwater resources don’t get replenished when it rains, and that can be a problem in areas that rely on precipitation for drinking water.

It Cools the Air

Grass naturally cools the surrounding environment. In fact, the grass on your lawn has the cooling effect of about 9 tons of air conditioning. It also provides cooler places for summer recreation than asphalt or concrete surfaces.

Grass Absorbs Sound and Reduces Noise Pollution

Grasses contribute to reductions in noise levels by absorbing and deflecting sounds. It acts like a blanket or insulation panel, absorbing sounds from people, cars, trucks, and animals. Grasses also reduce glare and light reflection.

There are so many ways that simply growing a lawn can help create a safer and cleaner environment.  Call the team at HYgreen for more information on this topic. Our professional team understands the environmental benefits of turf and we are here to help create a cleaner, greener planet.