Multiple Use and Restoration

Also important to the concept of conservation is the recognition that natural resources have multiple values. In addition to its value as livestock forage, grass, for example, also supports wild animal life, holds soil in place, maintains the productivity of soil, keeps soil and water relationships in proper balance, and helps guarantee streamflow or yields of water to underground channels. Grasslands, moreover, have aesthetic, recreational, and scientific values. All of the many values of grassland must be considered before a decision is made to use a grassland for a particular purpose. Ideally, an area of land can serve many purposes simultaneously or sequentially; i.e., can have multiple uses.

Another of the more hopeful aspects of conservation is the concept of restoration. A forest that has been cut or burned can, with care, regenerate itself. Areas that have been mined and left barren often can be revegetated with reasonable expenditures of money and effort. Depleted animal or plant populations recover their original abundance if suitably protected in an adequate habitat. The restoration of natural vegetation depends upon the ecological process of succession, in which plants with varying degrees of tolerance to extreme conditions in an environment invade a disturbed or barren area and replace one another until a stable, self-perpetuating community is achieved. Restoration is possible, however, only as long as species are protected and the genetic diversity of life is maintained. When species become extinct the restoration of past conditions becomes impossible.

Use of Global Resources

A further area of conflict lies in attitudes toward resources that are held in common, such as the atmosphere and oceans. In instances in which the use of such resources is essentially free to the user, and the power to control use does not rest with any recognized authority, the resource often deteriorates. Although each fisherman may feel that his individual activities have very little effect on the resources of the ocean, the effect of the activities of all fishermen may threaten the existence of those resources. Similarly, each automobile driver does not feel that he is contributing much to the pollution of the global atmosphere, but all automobiles throughout the world contribute a total level of pollution that most critics feel cannot long be tolerated. When such situations exist, a recognized controlling authority is usually seen to be necessary.

Spread of Modern Conservation Practices

Conservation ideas spread widely, being most readily accepted by those countries that had experienced sudden environmental changes. By the 1920s national parks were to be found on all continents. In 1924 the Soviet Union established the first of its now extensive system of natural reserves (zapovedniki). Conservation-oriented management of forest lands, which grew more from its origins in Europe than from practices in the United States, also became more widely accepted throughout the world. The scientific basis for the management of wild grazing lands for the sustained production of forage for livestock was established in U.S. national forests in 1913 and soon spread to other countries. Aldo Leopold in the United States, in 1933, wrote a textbook on game management, in which the conservation and management of wild animal life for such recreational purposes as sport hunting and fishing and for direct commodity values on a sustained basis received particular emphasis. Leopold's work drew heavily on earlier studies of animal ecology by Charles Sutherland Elton in England; in fact, the establishment in Europe of wildlife reserves and protective laws as well as the managing of lands to produce sustained crops of wildlife long preceded even Elton's work. Subsequently, the management of wild animals in extensive wilderness areas made major strides in Africa, which possesses unusual wildlife resources, and in the Soviet Union, which retains large areas of wildland.