With respect to the recent class discussions concerning the debate about using land for biofuel production, terminology seems to refer to land use changes primarily in terms of economic viability and total carbon cost. Although this language may often be useful in terms of convincing the political and economic sectors to retain forests for “carbon sequestration” in order to lower atmospheric CO2, and for having a “scientific” way to measure global effects of land use change. However, I believe that it is dangerous to exclusively or even predominantly use such an analytical approach to the removal or re/misappropriation of Earth’s natural resources.
Although it is currently popular to refer to just about everything in terms of carbon footprints, this terminology does not fully describe or account for potential disruptions to the ecosystems in question. When land-use changes, for example, are discussed in terms of whether or not the changes can lead to carbon neutrality, many other important issues are left out of, or at least sidelined, from the equation.
First of all, consideration of carbon release and capture of dry land seems to be taken into account more than that of the ocean, which is probably because we, as humans, rely most directly on dry land to live. This is problematic because oceans are a probable huge carbon sink, so when off-shore oil drilling is taking place, unaccounted-for carbon is being released. The natural habitats of many marine animals are also left out of consideration in many discussions about relative benefits of garnering energy from ocean sources. Drilling affects a huge number of animal and plant life that we really disregard in terms of effects of both oil drilling and pollution from oil refineries–also probably discounted because saltwater is not directly potable for humans.
Secondly, what never seems to be considered is that, morally, we do not have a right to discuss land use changes purely in terms of how it is best for us to use it to our own greatest advantage. The purview of what is to our advantage includes, carbon capture, land efficiency, zoning, pollution regulations (or lack thereof), retaining biodiversity, etc. Biodiversity becomes a predominant issue because it is often used as a paltry cover for morality. Despite the idea that we are doing the Earth a service by preserving biodiversity, what we are really doing is picking and choosing which biodiversity WE as a human species decide is important, and destroying that which we think is not.
What complicates matters is that efforts towards conservation are more often carried out by wealthier countries, which typically contain less of the highly-revered biodiversity that we are so concerned with. Preservation efforts in these countries, such as the U.S., leads to land-use changes in countries with higher biodiversity and less of a budget. Some of these issues were mentioned in the papers discussed in class; preservation of lands in the U.S. can lead to deforestation in places such as South America. The emphasis is not that one ecosystem is more important than the other, but that any sort of land use change has drastic consequences for the animals, plants, bacteria, etc. that were inhabiting that area.
To add some science to chew on in addition to my rant, here are some fun facts (from Vitousek P, Mooney H, Lubchenco J, Melillo J. 1997. Human Domination of Earth’s Ecosystems. Science 277:5325, p. 494-499.)
- Between one-third and one-half of the land surface has been transformed by human action
- the carbon dioxide concentration in the atmosphere has increased by nearly 30 percent since the beginning of the Industrial Revolution
- more atmospheric nitrogen is fixed by humanity than by all natural terrestrial sources combined
- more than half of all accessible surface fresh water is put to use by humanity
- about one-quarter of the bird species on Earth have been driven to extinction.
As the authors say:
The variety of human effects on land makes any attempt to summarize land transformations globally a matter of semantics as well as substantial uncertainty. Estimates of the fraction of land transformed or degraded by humanity (or its corollary, the fraction of the land’s biological production that is used or dominated) fall in the range of 39 to 50% (5) (Fig. 2). These numbers have large uncertainties, but the fact that they are large is not at all uncertain. Moreover, if anything these estimates understate the global impact of land transformation, in that land that has not been transformed often has been divided into fragments by human alteration of the surrounding areas. This fragmentation affects the species composition and functioning of otherwise little modified ecosystems (6).
Obviously the impacts of humans on the planet have been, and are, very widespread and destructive. When discussing other research papers in class in the future, I believe it would be beneficial to at least think about humanity’s desire to impact global change and requisition resources primarily in terms of our own benefit and how this is negatively affecting the environment.
That’s about all I have to say about this for the moment, but I highly recommend the above-cited paper as an excellent source of information about human impacts on global ecosystems.