This is the 8th blog in our Examining Climate series, where CCJ staff members and others will be sharing their favorite (or least favorite) climate solution, looking at the benefits and the costs in the hope of sparking an honest conversation about how we address the climate crisis and keep our focus on environmental justice. This blog was written by CCJ Field Coordinator Paul Fedore.
As the population of urban areas continues to grow worldwide, it is essential to reconsider how these environments are constructed in order to help us better adapt to a changing climate, to help to mitigate its effects, and to provide residents with adequate and healthy living conditions.
This is where urban greening can come into play. Effective urban greening involves a lot more than green spaces and rooftop gardens. When accurately applied, using a scientific approach, it can provide helpful tools for mitigating and adapting to climate change. Understanding the different types of green spaces and their benefits can make the difference between reaching the goal of adapting to and mitigating climate change or simply making an area look prettier and greener.
A report from the Royal Society indicates that urban green areas contribute to climate change adaptation by providing ecosystem services such as increased biodiversity and climate regulation. At the same time, they can also mitigate climate change due to their carbon capturing and storing potential. Ecosystem services are the many and varied benefits to humans provided by the natural environment and from healthy ecosystems (Wikipedia). The remaining part of this blog will examine the two main ecosystem services that urban greening can provide.
Biological diversity, or biodiversity, helps provide us with clean air to breathe, fresh water to drink and cook with, and good quality soil and crop pollination. The term refers to variability found at all levels of biology and is commonly broken down into three groups or types: genetic diversity, species diversity, and ecosystem diversity.
Genetic diversity is usually defined as the number of genetic characteristics (alleles and genotypes) in a species or the range of different inherited traits within a species. Genetically diverse populations are well-equipped to handle change. For example, suppose a deadly disease hits a population with many different characteristics that help to protect them against illnesses. In that case, the likelihood of that population surviving and not facing extinction is higher than a population with more homogeneous (or similar) traits.
An excellent example of a genetically diverse species is dogs. There are over 350 dog breeds, though only 199 are recognized as purebred by the American Kennel Club. Purebreds, as the name implies, have similar or the same genetic traits, whereas so-called “mutts” have more genetic diversity among them.
Species diversity refers to the number of different species present in an ecosystem, also known as species richness, and the relative abundance of each species, known as species evenness. An ecosystem thrives when it contains a diverse number of species that exist to maintain its balance. Ultimately, the different species in an ecosystem help each other to survive. So, it is crucial to keep a high number of different species to make a more efficient, productive, and sustainable ecosystem.
A national or state park is excellent for finding species diversity and richness. Many of these parks have several species of trees, plants, flowers, fish, insects, and other wildlife species, many being of high population.
We get oxygen through the process of photosynthesis within the plant community. Plants also provide us with many good sources of food and herbs used for cooking and medicine. Aquatic environments provide humans essential services, including water for drinking and irrigation, recreational opportunities, and habitat for economically important fisheries. They can also help remove harmful chemicals and contaminants from our water. According to the EPA, natural resources such as wetlands, stream buffers, and vegetated land cover can naturally filter out pollutants such as metals, pesticides, sediment, and overabundant nutrients that may affect water quality.
An excellent example of a diverse ecosystem is our planet. There are many different types of ecosystems covering the earth, and many of them contain other ecosystems. For example, rainforests are ecosystems, and so are the rivers within them; rivers have fish, insects, plants, and other living organisms that make up an aquatic ecosystem. Each ecosystem contributes something essential to the needs of human survival and the growth and protection of our environments.
Biodiversity at all levels is declining around the world. Though the change in climate certainly plays a significant role in these losses, several other factors are also at play, such as pollution and land use changes. There are many things we as humans can do to help increase biodiversity. For example, we can make wildlife more welcome by supporting plants and animals that live nearby and protecting habitats in our local areas by keeping our parks and other green spaces clean and free of litter. The more biodiversity there is, the more our ecosystems and habitats will thrive. The more they succeed, the more we can thrive as humans.
When discussing climate regulation, one of the most studied phenomena related to the benefits of urban greening is the urban heat island effect. Urban heat islands occur when cities replace the natural land cover with dense concentrations of pavement, buildings, and other surfaces that absorb and retain heat. This effect increases energy costs, air pollution levels, and heat-related illness and mortality. Through urban greening, we can create an environment that can help combat the urban heat island effect and the changing climate.
The cooling benefits of urban greening can be achieved with relatively small green areas and green corridors that use trees and bushes to connect parks and other green spaces. Living walls and rooftop gardens are other forms of urban greening that can positively impact the environment.
A living wall, also known as a green wall, is simply a vertically-built structure intentionally covered by vegetation. Living walls can remove air pollutants, reduce urban temperatures, help reduce heating and cooling bills by providing another layer of insulation for the building, improve biodiversity by providing replacement habitats for flora and fauna, lessen the impacts that rainwater has on a structure, lower noise, and increase human productivity and creativity.
Rooftop gardens are simply gardens grown on a rooftop and are an excellent choice for people living in the city or other urban areas where additional outdoor space is limited. Rooftop gardens provide several benefits. Your plants will likely get a lot of direct sunlight, which is great for their growth and health. The garden will help improve the air quality nearby and will likely become a habitat for wildlife such as birds, bees, insects, and other critters. The soil and plant cover will help to reduce the temperature inside the building, leading to lower energy costs. The garden will also provide a more decorative look and feel to the building, and if you plant foods in your garden, you will not have to spend money on those foods at the store. You can’t get much fresher than from the rooftop to the table.
Science has found that people living in urban areas with more green space report greater well-being than city dwellers that don’t have parks, gardens, or other green spaces nearby. Urban green areas have positive impacts on city dwellers’ physical and mental well-being. They are also linked to boosting creativity, promoting social interactions, improving real estate value, and lowering crime rates in adjacent neighborhoods.
When our environment is healthy and thriving, it provides us with essentials that many take for granted. The plants convert energy from the sun, making it available to other life forms within the habitat. Living organisms such as bacteria break organic matter down into nutrients to give the plants healthy soil to grow in. Pollinators are essential in plant reproduction as well. They fly around collecting pollen from flower anthers, the male parts of plants, and transferring it to the stigmas, the female parts. That plant or flower later yields fruit and seeds for humans and animals to consume or to use for many different purposes.
For urban greening to be effective in our communities, the terms and objectives must be clearly defined. We encourage implementing these and other green solutions throughout our communities to help us adapt to and combat the changing climate. Green spaces can be considered as investments in the public’s quality of life, health, and well-being.
If you are interested in learning more about urban greening or getting involved in our work, please contact our Field Program Coordinator Paul at 724-229-3550 ext. 8 or firstname.lastname@example.org.