Biodiversity is one of those hot words that many people like to throw around, regardless of their actual knowledge of the term. It seems that even people working within different disciplines have different senses of what it means—for a geneticist, it all begins with the genome, for an economist , it could be a commodity, a representation of the potential wealth of a country. However it is definitely one of the most important concepts for anyone studying and working in the environmental sector.
There are two major approaches to biodiversity: the species approach and the ecosystem approach. The species approach focuses on the importance of individual species to the overall wellbeing of human species, as well as the human impacts on biodiversity. Species are a vital part of natural capital and of earth’s support system. The species approach is fully aware of this, and of the human impacts on these species. Primarily, humans are having a huge effect on the extinction of these species. The rate has increased 100-1000 times faster than it was before the arrival of modern humans, and it is predicted to be 10,000 higher than background rate by the end of this century. The background extinction rate is the normal, low rate of species extinction. This rate is important, not only because of the ecological and economic services provided by these species, but as well as the right for the species to exist. Biological extinction is forever, irreversible loss of natural capital, can break or weaken connections in the ecosystem in which they had existed, can lead to secondary extinction of species with strong connections to extinct species. Extinction of species is an ecological smoke alarm in a sense, as it tends to signify a greater disruption in the whole ecosystem fabric. And of course, there is always the mass extinction: the extinction of many species in a relatively short period of geologic time. There has been around 5 previous mass extinctions due to major climate change or other similar large scale catastrophes. However, there is a potential of another great extinction caused by human hands. Human activities eat up a massive amount of the earth’s surface, and have threatened and caused the extinction of countless species. The greatest threats to any species, in order are: loss/degradation of habitat, harmful invasive species, human population growth, pollution, climate change, and overexploitation. So, how can we protect wild species from extinction? The book has several answers, including establishing/enforcing national environmental laws and international treaties, creating sanctuaries and taking precautionary measures. Although science may never be able to prove things absolutely certainly, if there is even a shade of danger, precautionary measures must be taken to preserve biodiversity. Once a species is gone, it is gone forever.
The ecosystem approach focuses on the preservation of the full ecosystem, making the argument that there is no point in preserving a species if its habitat! Ecosystems provide countless goods and services of value to human interests and intrinsically valuable. Forest ecosystems actually provide services that are far greater than the value of raw materials obtained from them, and they are threatened by cutting and burning, climate change and disease. Forests can be sustained by proper management, and recognition of their value beyond the simple commodities they provide. However, emphasizing the economic value of the forest system can be an intelligent way to advocate. Government subsidies that allow for unsustainable use of these forest systems needs to be ended and we must stop harvesting trees faster than they are replenished, especially in old-growth forests. Grasslands are also a valuable system, very productive and rich. They can be sustained by restorative measures as well as controlling the populations of the livestock who graze there. Parks and nature reserves have been an effective response towards preserving ecosystems, but require more effective protection than they have gotten. Furthermore, we must keep in mind that protecting the “real thing” is equally important, and that we cannot make up for ecosystem degradation or loss by simply attempting to recreate it. To sustain terrestrial biodiversity, threatened areas must be identified and protected, damaged ecosystems must be restored, and we must use reconciliation ecology, or in simple terms, acknowledging that we aren’t the only species in need of eco goods and service.
After reading about both of these approaches, I was struck by the poignant fragility of the ecosystem. Humans really know how to take advantage of what they got, huh? I think one of the most heartbreaking thoughts of the chapter is the potential biodiversity we have lost, that we may not have known existed. I visited the rainforest in Puerto Rico as a child with my family, and I have a distinct memory of our guía being obsessed with the slugs and minute creatures that populated the forest floor. I remember being unimpressed with the slugs in question, hoping to see a more exciting creature, but impressed by the guy’s enthusiasm. However, after all that I’ve learned in my science classes and environmental ones, many of these modest animals are vital to the survival of our ecosystems!
Although people place priority on saving the “celebrity” species, the whales and Bengal tigers of the world, more often than not, the small, unassuming little guys are the more valuable to the overall wellbeing of the system. I think the most obvious example is of the honeybee. We would be without many of our favorite foods if it wasn’t for these buzzing worker (check out this infographic) I guess the mantra of don’t judge a book by its cover really does have some truth in it!
Seeing as biodiversity is an integral provider of ecosystem services, what would be the best way to make biodiversity important for those not well-versed in the sciences nor environmental studies?
Which of the approaches towards biodiversity, the species or the ecological approach, works more coherently within the urban setting?