Lesson 30: Consumption and Production
In this lesson, we will learn about what distinguishes preservation from
conservation, the two different ways humans use ecosystems, and how rights of
tenure are tied to those uses. We will also learn about the concepts of maximum
sustainable yield and optimal population. Finally, we will look at the
significance of the essay "Tragedy of the Commons" written by biologist Garrett
Hardin.
The objective of preservation is to
ensure continuity of species and ecosystems regardless of utility. Preservation
and conservation are often confused.
Conservation involves sustainable use while preservation does not necessitate
any immediate use.
For example,
it is impossible to
maintain old growth virgin trees and harvest them. A second-growth forest is
needed for harvesting and this should be done in a sustainable way so that the
forest does not decline.
Human beings use natural ecosystems in 2 ways - for consumptive use and
productive use.
Consumptive use occurs when people harvest natural resources for food, shelter,
tools, fuel and clothing. Complete dependence for consumptive use is most
common in rural areas of the developing world.
Productive use occurs when people exploit ecosystems for economic gain.
Productive use is very important economically to individuals, organizations and
governments. For example, recently, global fisheries' catch of 83 million tons
was valued at $93.9 billion.
Both uses of natural ecosystems, consumptive and productive, depend on the
rights of tenure, or property rights over land and water.
There are four kinds of tenure:
- private ownership (which restricts access to natural resources)
- communal ownership (which allows community use of natural resources)
- state ownership (which implies regulated use of natural resources)
- open access (where natural resources can be used by anyone)
Maximum sustainable yield (MSY) is the highest rate of use that
a system can match with its own rate of replacement or maintenance.
Optimal population is the population size that
can be supported by the ecosystem in a healthy, sustainable way without
reaching the maximum value or carrying capacity.
In a landmark essay "Tragedy of the Commons" by biologist Garrett Hardin,
Hardin explained how the concept of free access can be misused. For example, in
England, when the king offered free pastures for cattle grazing, herders were
willing to overgraze areas for personal profit and to defeat any potential
competition by moving in to areas where other herders suffered losses. They
kept overgrazing until the pastures were completely destroyed. The lesson here
was that the pursuit of individual interests exclusively leads to tragedy for
all.
This tragedy can be mitigated and averted through regulation of access to
common areas and through private ownership.