Evaluating Biodiversity and Vulnerability

Identifying factors that lead to loss of diversity

Main five pressures on biodiversity are still present and even intensifying:

1. Habitat loss and degradation
2. Climate change
3. Excessive nutrients and other pollutants
4. Over-exploitation and unsustainable use of resources
5. Invasive alien species

There is something known as the Red List that shows the status of species in terms of their conservation status. You can see the list here.

It should be mentioned that biodiversity conservation is crucial. Biodiversity, be it genetic, habitat, or species, is one of the determining factors in an ecosystem's health. The above mentioned factors are putting pressures on the planet that it cannot absorb fast enough. Ecological footprints are exceeding the Earth's capacity to recover. All of this leads to a persistent loss in biodiversity that slowly reduces our ecosystems' resilience and compromises the resources on which we depend.

There are certain world trends that are occurring around the world:
- Habitats are declining.
- Abundance and distribution of species are declining.
- Change in status of threatened species.
- Threats in genetic diversity in domestic animals, cultivated plants, and fish species. This is due to interference with natural selection.
- Coverage of protected areas are increasing
- Marine Trophic Index has shown an increase, but has regional fluctuations.
- Ecosystems have become more fragmented.
- Water quality in aquatic ecosystems has been declining. Some areas have increased their water quality by dealing with point-source pollution.
- Nitrogen deposition has increased.
- The amount of invasive species has increased and are now a threat.
- Areas of forest, agricultural, and aquaculture ecosystems under sustainable management have increased, but there are several areas that still require more efforts.
- Humanity's Ecological Footprint is still rising.

Evaluating Contrasting Human Perceptions of the Issue of Global Warming

There are many different postures regarding the global warming phenomenon. Some state that global warming is a myth. Others do not deny it, but simply hold that the temperature rise is normal and is even beneficial to the Earth. Personally, I believe that there is enough scientific data to prove that the Earth's temperature is in fact rising. Also, regarding the point of view that it benefits our ecosystems, I believe it may be true in certain places. However, the changes in temperature are also harming other ecosystems that are just as important as the ones that are being benefited.

Another important issue that needs to be addressed when talking about global warming is the extinction and loss of biodiversity. Massive extinctions result from global warming, and the drastic changes in the environment can lead to loss of habitat which in turn limit the biodiversity in a given ecosystem.

I believe global warming is something that occurs naturally, but scientific and historic records clearly demonstrate that the rate at which the Earth is heating up is faster, and it is human activity that which is accelerating this process. I also hold that the planet is resilient enough to recover from the damages it suffers, but again, the damage is being done constantly and we are not giving the Earth enough time to absorb the pressures we are putting on it.

While I believe that global warming is a threat, I also consider that there are things that can be done. CO2 emissions are a major contributor to the temperature rise and while we cannot stop them completely, we could greatly reduce them. Corporations and governments should work at a large scale to reduce emissions, but also individuals and society as a whole should become more conscious and aware of the impact that each of our actions has on the planet. Only when we have reached true awareness will we be able to say that we are doing all we can to help the Earth.

Urban Pollution: Key Terms

Photochemical Smog: It is the product of several chemical reactions. Main components are nitrogen oxide and ozone after the reaction caused by UV light. Hydrocarbon free radicals found in smog can form aldehydes and peroxyacetylnitrate (PAN). Common in large cities.
PAN in photochemical smog can irritate the eyes.
Ozone: causes breathing difficulties, headaches, and fatigue.

Nitrogen Dioxide can be split into nitrogen monoxide and a free oxygen molecule that is then available to form ozone.
Nitric oxide can remove ozone.
When the ratio of NO2 to NO is greater than 3, the formation of ozone is the dominant reaction. If the ratio is less than 0.3, then the nitric oxide destroys oxygen.


Peroxyacetylnitrate: Products of the reaction between nitrogen dioxide, oxygen and hydrocarbons.

Catalytic Converters: These are used to reduce the carbon monoxide and nitrogen oxide emissions. It is made up of either platinum or a combination of platinum and rhodium.
Platinum catalyses the reaction of unburt hydrocarbon and oxygen to produce carbon dioxide and water.
The rhodium catalyses the reaction of carbon monoxide and nitric oxide to form carbon dioxide and nitrogen gas.

Reduction of NO to N2 must proceed more quickly than the oxidation of carbon monoxide to carbon dioxide or else all the carbon monoxide will be oxidized to carbon dioxide before it can be used to reduce the nitric oxide.

Acid deposition: The effect that acid rain has on ecosystems. The effects may not be immediately seen, but the restoration process takes a very long time.

Acid rain in soil - Each H+ replaces key nutrients. Hydrogen ions replace potassium or calcium ions. Plants begin to suffer due to scarce nutrients.