Human Impact on Biodiversity
Biology Senior Seminar
Thesis: Humans affect biodiversity on many levels and it is important to realize these effects on an individual, societal, and government level and attempt to minimize them in order to ensure a future for humanity.
IV. Human Actions
Many individuals do not think about the damage they are causing on biodiversity. However, it is important as humans to realize the impact we have on biodiversity because without it, there would be no human existence. If no changes are made in the ways humans use resources on earth, there will continue to be a degradation of biodiversity until human lives can no longer be sustained. Humans affect biodiversity by their population numbers, use of land, and their lifestyles, causing damage to habitats for species. It is important for humans to realize how their actions affect biodiversity and the importance of maintaining what biodiversity is left on the earth. Through proper education, and by demanding that governments make decisions to preserve biodiversity, the human population will be able to sustain life on earth longer.
Biodiversity is the term that is given to describe the variety of life on earth and the natural patterns it forms. It is the result of evolution, natural processes, and human influence. (Secretariat, 2000) Biodiversity involves diversity of genes within a species, of species within ecosystems, and of ecosystems in the biosphere (Frequently, 2005). Biodiversity is not determined by only one factor, but rather many factors that differ spatially and temporally (Climate, 2005).
Although many humans may not realize how important biodiversity is to them, it is clear that without it humans would not be able to exist. Each day humans use 40,000 species, most of which go totally unnoticed (Eldredge, 2000). Even though only a minority of humans realize it, biodiversity provides humans with food, water, oxygen, energy, detoxification of waste, stabilization of earth’s climate, medicine, opportunities for recreation and tourism, and many more things (Secretariat, 2000). Simply put, there would be no population of humans without biodiversity.
The most obvious indicator of biodiversity is the number of species on the planet. Currently there are 1.75 million species that have been identified; however, some speculate that there are at least 10 million living species on earth (Eldredge, 2000). To look at the loss of biodiversity, the number of extinctions of species should be examined. Rates of extinction are currently up to 40,000 species per year (that’s 100 per day or 4 per hour) (Wood, 2000). This rate is 50 -100 times the natural rate of extinction and is expected to increase in the coming years (Sherbinin, 2002). The extinction rate is of great concern because once a species is extinct, there is no chance of ever getting that species back on the planet.
Three main problems that cause species extinction are: habitat loss, degradation, and fragmentation (Noss et al, 2005). Habitat loss is described as the complete destruction of a habitat. An example of habitat loss would be logging of a forest. Habitat degradation is when a habitat diminishes to a point where it can no longer support biological communities (Effects, 2005). An example of this would be habitats that are polluted by industry. Habitat fragmentation is described as a habitat that is broken into smaller discontinuous segments of land for development (Mapping, 2005). An example of this would be putting a road in the middle of a habitat. All three of these problems that result in species extinction are directly related to human influence.
There is no clear way of determining the total impact that humans are making on biodiversity; however, it is obvious that many actions by humans are causing a decrease in biodiversity. To determine the total impact that humans are making on a given environment, the area of productive land and water needed to produce the item that is being consumed and the need to account for the waste being generated by humanity must all be taken into account according to management and production practices in use during that time (Wackernagel et al., 2002).
Direct or indirect actions by humans have resulted in the decrease of biodiversity. The Convention of Biological Diversity states that there are both indirect and direct human drivers. Some of the indirect human drivers are demographic, economic, sociopolitical, scientific and technological, and cultural and religious factors. Some of the direct human drivers are changes in local land use and land cover, species introductions or removals, external inputs, harvesting, air and water pollution, and climate change (Climate, 2005).
Human activity has substantially changed one-third to one-half of the world’s surface (Frequently, 2005). In the next 50 years it is expected that humans will seriously impact 50-90 percent of land in developing countries. This is a result of growth in population and in over consumption of natural resources (Mapping, 2005). The population of humans is, what many consider, the root of the biodiversity problem (Eldredge, 2000). The number of humans on earth, as of July 2005, is at 6.4 billion (World, 2005). The increase in human inhabitants causes a problem because with it comes a need to convert natural habitats to land for human consumption.
One way that
the humans have been able to sustain their growth is by converting natural
habitats to fields where foods can be produced. At least 23 percent of the
earth’s land is being used for agriculture (31 percent of all land is unfarmable). In the
Human actions have also played a role in climate change, which is also causing great danger for biodiversity. The change in climate is due to increased atmospheric concentrations of carbon dioxide, which causes increased land and ocean temperatures, and changes in precipitation and sea level rise. With the change in climate also comes a change in species. Climate affects the timing of reproduction and migration, the length of growing seasons, species distributions and population size, and the frequency of pest and disease outbreaks. It is also expected that the change in climate in the 21st century will have a much higher rate than the past 10,000 years and create an even bigger impact on biodiversity (Climate, 2005). It is expected that 80 percent of biologically rich regions will suffer great losses of plant and animal species because of global warming. The rate of change of habitats is expected to increase up to ten times due to global warming (Sherbinin, 2002).
Poverty and Biodiversity
Biodiversity affects everyone to
varying degrees. People that live in poverty depend heavily upon nature to provide
them with resources to live. In third world countries logging has become a
common activity of the poor. It is a huge problem in many developing countries
because it is destroying natural habitats, yet it seems to be one of the only
ways that people can make enough money to support their families. The New York
Times recently ran an article about individuals in
The degradation of the environment will affect both poor and industrialized nations. However, The developing nations will be the ones that are affected the most by the degradation of the environment by increasing poverty, reducing labor productivity, and exacerbating the current economic social crisis (Mapping, 2005). Developing nations do not have the resources to help their citizens find an alternative to use nature for survival.
Educating individuals in developing
countries about the need to preserve biodiversity is a must for ensuring human
survival. Educating locals on the impact people are making on the environment
and showing people how they can live in equilibrium with nature, will help
preserve biodiversity without causing further oppression. Many times
individuals do not realize that there are alternative ways of obtaining money
that do not put the environment into jeopardy. For example, in the case in
General education in developing countries is very important to biodiversity even if it does not focus directly on sustainable living. There have been significant studies that have shown that educating and empowering women lead to a decrease in birthrates which would make a huge impact on population growth, especially since developing nations have a higher birthrate compared to industrialized nations. Simply educating individuals, all individuals, not just impoverished ones, about their impacts on biodiversity is a step in the right direction. (Eldredge, 2000)
Although there are actions
individuals can make that can assist in helping the biodiversity problem, it is
important for governments to take actions that will provide a larger scale
effect on saving biodiversity. The George W. Bush administration is not known
for protecting the environment. President Bush has eliminated the roadless rule, which was a rule that kept logging and roads
from being present in 60 million acres of national forests. Bush has also cut
42 million acres of critical habitat from the 83 million acres that are needed
for threatened and endangered species. There has been a great decrease in the
amount of designated wilderness in the
Bush made another decision against the environment by not ratifying
Some local governments are not in agreement with the
Although there is much evidence that the Bush administration does not truly care about the environment, they have made a few contributions that are beneficial to the environment. Bush has made a debt for nature swap, which is when a country’s debt is redeemed by supplying land reserves and salaries for people to monitor and protect reserves (Dobson, 1996). There are two ways in which debt for nature swaps can occur. The first way is through bilateral debt swap, which occurs between the two governments. The second way is through commercial debt swap, this occurs when a nongovernmental organization purchases the debt at a discount from the creditor government. The nongovernmental organization then organizes the conservation project with the debtor government. (World Wildlife, 2002)
Biodiversity is an issue that affects everyone and therefore everyone should be aware of their effect on biodiversity. As biodiversity decreases on earth, so do the chances of human survival. Therefore, it is important to educate people on living in equilibrium with the environment. It is also important to make sure that the government is making laws that will ensure biodiversity for the future and not focus on shortsighted economics. If humans become extinct, it will likely be a result of their own action or lack of action. Hopefully humans will realize this before it is too late.
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