SECTION 2
In most developing countries topographic mapping has preceded all other types and has formed a foundation for subsequent mapping programs. Usually geological surveys are built onto these topographic bases and become the planning vehicle for mineral resource development. This is followed by such important studies as road and railway development, improvement in regional agriculture, development of water supplies and hydro-electric power from dam construction, large-scale cultivation of new crops and other aspects of national planning required prior to undertaking major capital projects. Other major mapping projects built on a topographic base have included: tourism planning and development; census studies; forestry management; industrial plant location; land ownership; land usage; environmental hazards; ecological studies; transportation; archaeological and anthropological studies; investigation, control and use of water resources; cadastral surveys; urban studies; sea defences; soil surveys; economic assessments; health investigations; irrigation systems; land reclamation; mosquito control in marshes; airport siting; housing developments; vegetation classification; etc. There have also been many schemes implemented because of military and internal security considerations and significant boundary disputes.
To the obvious economic and security aspects listed above must be added a number of benefits which are difficult to quantify. These would include the significance of mapping in education and a variety of recreational activities.
A reading of the above list will show that many of the subject areas have a direct impact on the marine environment. In fact, the division of the natural world into terrestrial and marine aspects is an artificial one as each affects the other.
The economic welfare of a nation or region is directly dependent on the resources available to it and on the ability of the people to use these resources to their benefit. Inadequate knowledge often results in resources being over-exploited or even destroyed before they are truly appreciated. These resources include all of the exploitable minerals, soils, vegetation, wildlife and water. To derive benefits from a resource, it must first be identified and then managed. The map is the most efficient method of displaying the necessary resource information.
Many emergent nations begin by establishing a geodetic survey network to construct an effective topographic mapping series. Not only are these maps vital for recording and planning of any kind, but also they are an economic investment that produces a major, though highly diversified return. They create economic benefits by preventing a great deal of unnecessary measurement, by eliminating an enormous amount of expensive field work and by shortening the time required to assess a developmental proposal.
Once the basic frame of the survey control network for topographic or planimetric maps is in place, it can become the base on which special studies both on land and in the marine environment can be built. This is not to infer that mapping is impossible without a survey control network; in fact some aspects of this manual will concentrate on simple mapping techniques using readily available sources of information. Once the overview or reconnaissance phase is over, however, accurate measurements tied to survey control networks are usually necessary if major development is to take place.
Despite the benefits of national standard mapping, the current coverage of world topographic mapping is far from complete. Only 42% of the countries of the world are mapped at the scale of 1:50,000, considered to be the most useful scale available. At present rates initial coverage won't be complete until the year 2000. A recent study by the International Hydrographic Office found that only 40% of the marine area covered by the Exclusive Economic Zone (EEZ) of the 39 countries it surveyed was adequately charted.
Standardized mapping tends to have a long life. Topographic maps, for example, are typically in circulation for 15–20 years before they are updated. Many potential users and uses for such a product cannot be foreseen. Some hydrographic charts have been in continuous usage, through regular updates, for 70–100 years and their economic, social and convenience benefits can hardly be overstated. Such maps will easily return their cost many times over during their useful life and some will make possible a return on investment and human benefit unmatched by virtually any other developmental expenditure.
Maps have a catalytic effect on development and prevent the main source of haphazard planning which is the lack of easily understood information. In relation to the development and exploitation of marine resources, a mapping program can address critical information needs concerning, for instance, fisheries, oceanography, geology, navigation, coastal development and local political realities. In addition, such important topics as education and training can be addressed.
