The Soil and Vegetation section in the SITES rating system talks about soil management and construction priority. Such strategies are based on the idea of conserving the local ecosystem and maintaining its biodiversity. Using appropriate vegetation, managing invasive plants, and restoring biodiversity are the key ingredients to give us environmental, economic, and social benefits.
What is Biodiversity
Biodiversity, also known as biological diversity, refers to the variety of life forms found on Earth. It encompasses all living organisms, such as genes, species, communities, and ecosystems.
In an ecosystem context, it typically covers these three main components: generic diversity, species diversity, and ecosystem diversity.
Generic diversity means the generic variation within a species, such as the different feather colors of birds.
Species diversity means the variety of different species within a given ecosystem, such as monkeys, birds, and deer in one forest.
Ecosystem diversity refers to the variety of distinct ecosystems in one geographic area. For example, there are beaches, marshes, hemlock forests, and peatlands in the state of Maryland.
Because "biodiversity" sums up the richness and evenness of the species in one location, we often use the term in the context of ecosystem services, climate regulations, economics, or even food security in one neighborhood.
Why does Biodiversity Matter?
Biodiversity matters for its utilitarian value and intrinsic value. From a utilitarian perspective, our ecosystem has provided us with food, fuel, shelter, and even herbs with healing properties. With adequate biodiversity, we could receive enough supply from the natural resources for what we need in life.
From an intrinsic perspective, biodiversity refers to its inherent worth, which is true and fundamental to the variety of species, which is independent from other external factors or from market conditions. For example, the spiritual connection we feel when walking in the woods, or the thrills we get from watching the birds.
Why is biodiversity management necessary?
As mentioned above, biodiversity has brought us many values; managing it is necessary because it is a way to ensure the health and stability of the ecosystem and thus to support human well-being. Imagine each ecosystem is made up of certain species; removing species from any ecosystem can weaken the ecosystem and lead to an imbalance in the natural cycle. Similar to the cornerstones of a pyramid, removing any of the stones will impair the structural integrity of the pyramid.
How to measure biodiversity?
Biodiversity can be measured using various methods, such as counting the number of different species in one given area or counting the variety of ecosystems in a specific region. One of the popular metrics is the Simpson Diversity Index. It is a measurement to quantify the variety of species in a community, and an indicator to describe the richness and evenness of species in an ecosystem. It can be described as the following formula: Index D=1-Σ(n/N)², the higher the value, the more diversity.
[P.S. We don't only use the Simpson's Diversity Index to measure the variety in an ecosystem. You will see a neighborhood assessment using the Simpson Diversity Index to calculate the probability that any two randomly selected dwelling units in a project are of a different type. In the LEED ND rating system, the more diversity a development project has, the more points a project could achieve. ]
How can Biodiversity contribute to Our Built Environment?
Biodiversity plays a critical role in balancing and fulfilling the purpose of an ecosystem. By integrating biodiverse design components in urban areas or any built environment, we can restore the interruption of existing ecosystems and further enhance the local ecosystem's value, such as regulating temperature, improving stormwater runoff, conserving environmental pillars, extending the current natural habitat and services, or preventing flood hazards, etc.
With biodiversity, the natural habitats are gradually enhanced, and natural hazards associated with climate change, such as flood events or food insecurity, can also be mitigated.