After completing this chapter, you will be able to
- Explain the differences between renewable and non-renewable natural resources.
- Outline the ways that appropriate management practices can increase the harvest of biological resources.
- Describe at least two case studies of the degradation of potentially renewable resources and explain why those damages occurred.
- Distinguish between economic growth and economic development and outline the nature of a sustainable economy.
For about five decades now, we have been able to examine photographs of Earth as viewed from space. Images from that perspective show that Earth is a spherical mass, with a blue oceanic surface, brownish-green landmasses, and a clear atmosphere except where visibility is obscured by whitish clouds. Such images also reveal that beyond Earth and its atmosphere is the immense, black void of space – an extremely dilute, universal matrix. If we divert our attention from this compelling image of spaceship Earth and focus instead on the unimaginably larger abyss of space, we cannot fail to be stirred by the utter isolation of our lonely planet, the only place in the cosmos that is known to sustain life and ecosystems.
With such a lucid image of Earth in mind, it is not difficult to understand that the resources necessary to sustain life are limited to those already contained on the planet. That is, with one critical exception – the electromagnetic radiation that is continuously emitted by the Sun. A tiny fraction of that solar energy irradiates Earth, warms the planet, and drives photosynthesis. With the exception of sunlight, however, Earth’s resources are entirely self-contained and finite.
It is an undeniable reality that all organisms must have continuous access to resources obtained from their environment. Plants and algae, for example, require sunlight and inorganic nutrients, while animals and heterotrophic microbes must feed on the living or dead biomass of other organisms. Because their organisms must be nourished by environmental capital, the concept can also be extended to ecosystems in their totality. The necessary resources must be available in at least the minimal amounts needed to sustain life, and in larger quantities in ecosystems that are increasing in biomass and complexity, as occurs during succession.
The same reality holds for individual humans, our societies, and our economic systems. All people and their enterprises are subsidized by the harvesting of resources from the environment (including those taken from ecosystems). These necessities must be available in the minimal amounts needed to sustain human life, and in much larger quantities in economic systems that are growing over time. An obvious conclusion is that economic and ecological systems are inextricably linked. Indeed, this is an undeniable fact.
The main connections between economic systems and the natural world involve flows of resources from the environment (including ecosystems) into the human economy, and offsetting flows of disused materials, by-products, and heat (these are sometimes referred to as wastes) from the economy back to the environment. Associated with these interchanges of materials and energy are many kinds of damage caused to natural and managed ecosystems. The damages may be caused by disturbances associated with harvesting natural resources, by emissions of pollutants, and by other stressors related to anthropogenic activities, especially those occurring in heavily industrialized economies.
An ultimate goal of environmental studies to understand how the use of natural resources and changes in environmental conditions are related to a sustainable economic system and to the quality of human life. Ultimately, a sustainable economy is one that runs forever, and that operates without a net consumption of natural capital – the rates of resource use are equal to or smaller than the rates at which the resources are regenerated or recycled. This definition focuses on the resource-related aspects of sustainability. Also important, however, are environmental damages that may be caused by the extraction and management of natural resources. The social context must also be considered, particularly the ways that wealth is shared among the people who are participating in an economy.
In this chapter, we examine the broader issues related to the use of natural resources in economic systems. Initially, we examine the characteristics of non-renewable and renewable resources. Non-renewable resources are finite, do not regenerate, and therefore are diminished by use. In contrast, renewable resources can regenerate and may be managed to maintain or increase their productivity, and we describe practices that foster those goals. This is followed by an investigation of the reasons for a catastrophic but remarkably common phenomenon – the depletion of potentially renewable resources through excessive use. Finally, we consider the notion of sustainability, a topic that is critically important to the long-term health of both economic and ecological systems. This chapter deals with natural resources in a conceptual manner; Chapters 13 and 14 investigate the actual use of resources in the international and Canadian economies.
All natural resources (also known as natural capital) can be divided into two categories: non-renewable and renewable.
Non-renewable resources are present in a finite quantity and do not regenerate after they are harvested and used. Consequently, as non-renewable resources are used, their remaining stocks in the environment are depleted. This means that non-renewable resources can never be used in a sustainable fashion – they can only be “mined.” Examples of non-renewable resources include metal ores, petroleum, coal, and natural gas.
Although continuing exploration may discover additional stocks of non-renewable resources that can be exploited, this does not change the fact that there is a finite quantity of these resources present on Earth. For example, the discovery of a large amount of metal ore in a remote place may substantially increase the known, exploitable reserves of those non-renewable materials. That discovery does not, however, affect the amounts of the metal present on Earth.
Metals are often used to manufacture parts of buildings and machinery. To some degree, the metals can be recovered after these uses and recycled back into the economy, effectively extending the lifespan of their reserves. However, due to the growth and increasing industrialization of the economy, the demand for metals is accelerating. Because recycling cannot keep up with the increasing demands for metals, large additional quantities must be mined from their known reserves in the environment. For valuable metals, such as gold and platinum, there is a high efficiency of recycling, but it is much less so for iron and other less-costly metals.
Fossil fuels are the other major category of non-renewable resources. They are mostly combusted to provide energy for transportation and heating, which converts their organic compounds into carbon dioxide and water, which are released into the environment. Some of that CO2 and H2O may be absorbed by plants and other photosynthetic organisms and be converted back into organic materials, a process that might be interpreted as being a kind of recycling. However, the rate at which this happens is insignificantly small compared with the release of the CO2 and H2O by the combustion of fossil fuels, so these materials should be viewed as being as non-renewable as metals are.
A more minor use of fossil fuels is to manufacture various kinds of plastics. These synthetic materials can be recycled after initial uses, which does help to extend the lifespan of the reserves of fossil fuels. Nevertheless, because the dominant use of fossil fuels is as sources of energy, they essentially flow through an industrial economy, with little new recycling.
Image 12.1. Non-renewable resources can only be mined. This is a view of the Etaki open-pit diamond mine in the Northwest Territories. Three open pits can be seen as a cluster, plus another at the top-left of the image, along with an extensive tailings-disposal area and other infrastructure. Source: Jason Pineau, Wikimedia Commons; http://commons.wikimedia.org/wiki/File:Ekati_mine_640px.jpg .