What is Biodiversity?
Biodiversity is the variety of life on Earth (Hooper et al. 2005). It can be studied on many different scales (Oliver et al. 2015). Look out into your backyard and you will see biodiversity; there is grass, there are a few different types of trees, there is a berry bush, there is a vegetable garden, there are birds, there are rabbits, and there are many different types of insects. The variety of plants and animals in your backyard constitutes the biodiversity of your backyard (Hooper et al. 2015). You can also look at biodiversity on a larger scale, such as the biodiversity in your county. In your county, there are many more species of trees, there are several different types of berries, there are many farms growing vegetables, there are many different species of birds, there are larger mammals, there are many types of insects, and there are rivers full of amphibians and fish. In contrast, we can also study biodiversity on a smaller scale; at the genetic scale (Oliver et al. 2015). Consider humans, we are all the same species, but we all look very different from one another. This is because we each have a different set of genes encoded in our DNA which makes each of us unique (Durham 1991). Just like there is genetic diversity in the human population, there is genetic diversity in each of the species we find in our backyard, in our county, or in our oceans (Oliver et al. 2015).
What is Resilience and how does it relate to Biodiversity?
Today, we live in an ever-changing environment. It is important to have biodiversity in our environment because it makes our ecosystems more resilient (Oliver et al. 2015). Let’s think about our backyard again. The trees in our backyard provide us with something that we need and want in the hot summer months, shade. Shade is considered an ecosystem service; it is a benefit that humans receive from the environment (McLeod and Leslie 2009). Now imagine a big storm comes through your area and all the cottonwood trees in your backyard fall over with the high winds of the storm. If the only type of tree in your backyard was cottonwood, then you would no longer have shade in the summer. Luckily, you also have maple trees in your backyard. These maple trees have a much larger root system, so they can stay standing through the high winds of the storm. So, even though all the cottonwood trees in your backyard are gone, there are still maple trees to provide you with shade in the summer. Having biodiversity of trees in your backyard allows your backyard to be more resilient to storms. Your backyard changed, but it was still able to provide you with the ecosystem service that you wanted, shade. The biodiversity of your backyard ecosystem allows for resilience.
Now let’s look at the biodiversity on the smaller scale, let’s consider genetic biodiversity. Your neighbor has only cottonwood trees in their yard; so, you assume that all their trees have blown over in the storm. Yet, when you look over at your neighbor’s backyard, you see that some cottonwood trees are still standing. Why is this? It turns out that while your neighbor does not have a biodiversity of different types of tree species in their backyard, they do have genetic biodiversity in the cottonwoods planted in their backyard. Some of the cottonwood trees planted in their backyard have genes that code for a larger root system. These trees make up a genetically defined group of cottonwood trees that are different from the genetically defined group of cottonwood trees that blew over. The genetic diversity among cottonwood trees in your neighbor’s backyard allowed for resilience of not only their backyard ecosystem, but also of the cottonwood trees. You still have shade in your backyard, but now you must sit under a maple tree for shade. Your neighbor still has shade, but they can still sit under a cottonwood tree for shade.
You planted certain trees in your backyard and continued to maintain the health of these trees; this is a way in which your backyard was managed. By maintaining a diversity of trees species or genetic diversity of cottonwood trees, you can make your backyard ecosystem more resilient to environmental effects (Bagley et al. 2002). Just like you can manage your backyard to be more resilient to storms and a changing environment, we can manage other natural resources to maintain a heathy, productive, and resilient ecosystem that will continue to provide humans with the services that they want and need from the natural environment (McLeod and Leslie 2009; Berks 2012; Lester et al. 2010).
Genetic Diversity and Dungeness Crab
In Oregon, fisheries are an important natural resources that provide us with many ecosystem services, including food. Just like shade is an ecosystem service we obtain from the trees in our backyard, seafood is an ecosystem service provided by the ocean. One of the most valuable ocean fisheries in Oregon is the Dungeness crab fishery (Rasmuson 2013). In order to continue catching and eating this natural resource into the future, the fishery is managed. There is uncertainty in what environmental changes or extreme events will occur in the marine ecosystems in the future, but understanding and maintaining the genetic diversity of the Dungeness crab can provide a foundation for a species that has greater resilience to change. It is inevitable that environmental events will negatively impact some of the Dungeness crab along our coasts, but diversity of the population’s genetic composition can increase the likelihood that some of the Dungeness crab will survive. Genetic diversity of the Dungeness crab along our coasts is just one of many aspects of the species that can influence how plentiful the Dungeness crab fishery is along our coasts in the future.