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Global environmental issues

19 January, 2016 - 16:25

You have probably read or heard about climate change in the newspapers or on television, perhaps in reference to the meetings in Copenhagen in late 2009, etc. Climate change is the consequence of our neglect of and damage to the environment since the industrial revolution and our relentless and increasing appetite for fossil-fuel based energy. It is an imminent global environmental issue that not only affects us now, but will likely continue to affect us throughout the 21st century. Climate change is caused by global warming, which is caused by the emission of greenhouse gases. We will discuss climate change as an emerging environmental crisis later in Unit 10 so we won't go into detail on this issue here.

In this section, we focus on two critical issues: habitat/biodiversity loss and depletion/over-exploitation of resources. These are caused directly by human activities such as the clearance of rain forests for land and timber, and over-extraction of ground water for potable use; as well as indirectly as a result of pollution from human activities, such as air pollution resulting from acid rain causing deforestation and discharge of chemicals into the ocean destroying coral habitats.

Do you know the driver behind these critical issues? The driver is the exponential world population growth. Let's examine the chart shown below. 

United Nation's forecast on world population growth


Figure 1.1 shows the United Nation’s forecast on world population growth. You can see from Figure 1.1 that the world population reached its first billion around 1815. The first billion population increase took 112 years, reaching 2 billion in 1927. Yet it only took 33 years, in 1960 to reach 3 billion; 14 years, in 1974, to reach 4 billion; 13 years, in 1987, to reach 5 billion; and 12 years, in 1999, to reach 6 billion. The world population at the end of 2008 was about 6.6 billion, and it is forecast to reach 9.2 billion in 2050, a 40% increase in about 40 years.

Figure 1.1 World population

You may ask: what does population growth have to do with our environment? Please see the answer here.

What does population growth have to do with our environment?

To answer your question: such population growth creates land use conflicts in the need to feed and house substantially more people. How many people can our earth support? Are we over-exploiting our resources? A recent concept is the ‘Ecological Footprint' pioneered by Rees and Wackernagel in 1996, which measures a population's demand in nature in a single metric: area of global biocapacity. It represents human demand on nature. If our global ecological footprint is greater than the global biocapacity, we are using up more than what is affordable. In other words, we are over-drafting our bank account, and we are borrowing against the future, leaving nothing for future generations.

The WWF's Living Planet Report 2008 gives a global ecological footprint in 2005 of 17.5 billion global hectares (gha), or 2.7 gha per person. On the supply side, the total productive area, or biocapacity, was 13.6 billion gha, or 2.1 gha per person. That means that we had already over-exploited mother nature by 0.7 gha per person in 2005. If we continue at such a pace with a business-as-usual-attitude, we will need two planets by 2030 to meet our needs.

The following figure shows the cause and effect relationships among biodiversity loss, human pressure and ecological footprint.

Figure 1.2 Cause and effect relationships of biodiversity loss, human pressure and ecological footprint 
 

Reading 1.1

WWF (2008) Living Planet Report 2008: http://assets.panda.org/downloads/living_planet_ report_2008.pdf

  • Pages 2–5: Introduction  
In short, the ecological footprint concept is about human's demand on the planet's resources.
 
  • Pages 14–15: Ecological footprint of nations  
Based on some assumptions, it is possible to compare such footprints for developed and developing nations.

 

After reading the above, you should have an understanding of the concept of the ecological footprint and the critical issues of habitat/biodiversity loss; depletion/over-exploitation of resources, particularly water; and environmental degradation due to pollution. You will have a better idea of how different countries perform in terms of their ecological footprint compared to their biocapacity. Table 1 in the WWF report (pages 32–39) lists the ecological footprint and the biocapacity per capita of nations in 2005. In the Asia-Pacific, Australia had the highest ecological footprint per capita: 7.8 gha. Yet due to its vast land area and low population, Australia had relatively high biocapacity per capita: 15.4 gha. Japan on the other hand, a small densely populated developed country, showed an ecological footprint per capita of 4.9 gha and a low biocapacity of 0.6 gha. China, a large developing country with large population, had an ecological footprint of 2.1 gha per capita in 2005 yet a biocapacity of only 0.9 gha per capita.

WWF Hong Kong also produced a report on Hong Kong's ecological footprint. You are assigned to read selections of the report to give you a better understanding of China and Hong Kong's ecological footprint and biocapacity, some suggestions on how Hong Kong needs to reduce its ecological footprint, and some frequently asked questions and technical notes on ecological footprint. 

Reading 1.2

WWF Hong Kong (2008) Hong Kong Ecological Footprint Report 2008: Living Beyond Our Means, ‘China's ecological footprint and biocapacity' and ‘Hong Kong's ecological footprint and biocapacity', pp. 7–9; and ‘Hong Kong: Transformation to sustainability', pp. 14–15:

http://www.footprintnetwork.org/images/uploads/ Ecological_Footprint_HongKong.pdf

The report shows that even though Hong Kong has compact housing and an extensive public transportation system, its ecological footprint per person has doubled since 1965. The government has moved towards sustainability through closer collaboration across the Pearl River Delta, optimization of fuel mix for power generation and development of wider use of renewable energy.

Hong Kong had an ecological footprint of 4.4 gha per capita but a biocapacity of only 0.017 gha in 2008; an over consumption of more than 250 times, indicating Hong Kong's lack of natural resources and reliance on imports to sustain the population.

Having read extracts from the above reports, try Activity 1.1.

If you are interested in finding out more about the Ecological Footprint and biocapacity, you are encouraged to explore:

Reading 1.3

Global Footprint Network (2009) ‘Ecological Footprint atlas 2009' and ‘Global Footprint network 2009 annual report: How we can bend the curve':

http://www.footprintnetwork.org