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Coastal Zone Space: Sites for Conflict

Edward D. Goldberg
Scripps Institution of Oceanography
La Jolla, California, USA

A Presentation Made at the United Nations University
on 22 January 1993
Tokyo, Japan

The coastal zone, the areas where the oceans meet land, are much sought after for habitat, tourism and recreation, mariculture, transportation, waste disposal, mining, energy production and fishing. The occupants change as a consequence of economic and social pressures. All of these activities place stresses on the 440,000 km. of the world's coastal zone. In many countries of the world the military occupies a non-trivial portion of this area. With the potential of a release of property to the civilian sector, decisions will have to be made as to its new uses.

Herein I will present some observations on the competitors for coastal space and the potential environmental degradation that will accompany their activities. But first of all we will consider the present and future inhabitants.


For many, the coastal zone is a most attractive place to live. The association with the sea draws many people, especially those that today want a better style of living. For example, there is a marked movement of people primarily from low latitudes to coastal zones at higher latitudes seeking a better life through improvements in work opportunities, habitat, medical facilities and educational systems. Examples of this migration may be found in many regions: from the countries of the south Mediterannean to those of the north Mediterannean; from Mexico and Guatemala to California; from Haiti and Cuba to Florida; from the Bahia region to the Rio Grande area in Brazil.

In many cases, the moving people create discomfort for the host population. Although often they will work for low pay and in positions that are disdained by the natives, they are looked upon without respect. For example, Italy has recently been flooded by immigrants from Africa, Asia and eastern Europe. Until this time Italy had remarkably liberal immigration policies with an intent to create a multi-racial society. Although these laws were only formulated in March, 1990, seventy-five percent of the Italian citizens now favor closing the border to all new immigration. The recently arrived migrants exacerbated an already serious unemployment problem, created a perception of being purveyors of crime, disease and drugs, and were conspicuous most evidently by their appearance. Often out of work and without housing, they flooded the beaches of Romany and Tuscany. Relevant governmental agencies have difficulties coping with such situations. The scenarios occur in similar patterns in other parts of the world. The hordes of people, migrating to coastal regions, constitute a strong competitor for coastal space.


Tourism is probably the world's largest single industry, accounting for at least five percent of the world's total gross national product (Table 1). The numerical involvement of the coastal zone is not as yet firmly established, but for France it appears to be associated with about twenty percent of the activity. For Tunisia, the number is closer to eighty percent. The increased inclination of people to roam, coupled with increased leisure time and financial resources will continue to spark tourism.

The rate of increase of tourism is greater in the developing world than in the developed part. This is especially evident in the Caribbean Islands whose economies to a large extent are based upon tourism. The contribution to the combined Gross National Products of the region is estimated to be forty-three percent through expenditures at hotels, restaurants, shop sales, tours and native performances. In 1987 5.6 million cruise passengers came to the Caribbean. Cruise populations throughout the world have been increasing at a double digit rate (Table 2).

Thus it appears the demand for space to accommodate businesses involved with tourism will increase throughout the world. The profitability of touristic enterprises makes them a strong competitor for choice coastal space. The businesses provide work opportunities for the natives and often bring in hard currency for much needed imports.

But the stability of touristic ventures depends upon a healthy marine environment that can provide recreational facilities to the active visitors and seafood to the hungry ones. However, this is sometimes challenged by inadequate waste treatment facilities which allow the entry of toxic pathogens into coastal waters. These flows, with potential threats to human health through the ingestion of seafoods and secondarily through direct exposure in sea sports, have clear and undesirable consequences. The recent epidemic of cholera in the western coastal areas of South and Central America had a devastating impact upon tourism.

The investment in appropriate sewage treatment facilities is often not made in developing countries as other activities such as health care, education are given a higher priority. Still, the possibility that such investments will bring a substantial return over long time periods should not be discounted.


Aquaculture, which encompasses activities in both fresh and salt waters, accounts for about ten percent of the world's harvest of fish and shellfish (Tables 3 and 4). In some countries it is dominated by freshwater finfish culture but marine activities are clearly on the rise. The cultivation of crustaceans on a worldwide basis increased nearly ten-fold between 1975 and 1985; the price of shrimp has shown a correspondng twenty-five percent decrease.

Mariculture makes significant economic contributions to some nations and is improving the diets of people around the world. With decreased fishing from the wild and with a rising number of complaints that the great efficiency of our commercial vessels is driving some species to extinction, the mariculture has become most attractive and is drawing many adherents. Although farming in the coastal zone disturbs the panorama of the waters with an assemblage of pens of one type or another, its positive aspects rise to the fore. It is successful and improvements are prophesied for the future. In the mid-1980s synthetic growth hormones were fed to fish which led to weight gains twice those of controls. However, the economics were against immediate implementation of such techniques on a commercial basis as the synthetic hormones were expensive and the efficiency of uptake was low. Research continues and may further spark this activity.

Besides demands upon coastal zone space, maricultural production can disturb the quality of the coastal environment. There can be the loss of natural habitats such as the mangrove forests in the southeast Pacific, Central and South America where the shrimp are grown. These ecosystems are a most valuable part of the marine environment and any loss is disturbing to ecologists.

But perhaps more important is the creation of anoxic environments. Fish farming in cages produces organic residues from uneaten food and metabolic wastes. The materials sink to the bottom and through microbial decomposition release dissolved plant nutrients such as phosphate, nitrate, silicate and ammonia into the waters. Enhanced algae growth can follow and serious pollution problems can develop. For example, Hong Kong Island has degraded environments under mariculture rafts which occupy waters in what were once considered clean and beautiful areas. This situation has outraged another com-petitor for this coastal space, the Hong Kong Yachting Association, which represents user communities who desire the waters for canoeing, windsurfing, motorboating, swimming, sailing, snorkeling and SCUBA diving. Mariculture accounts for fifty percent of the total fresh fish consumption in Hong Kong and has an annual value of $25 million, most probably comparable with the cash flow of the Yacht Club. Some environmental damage can be mitigated by the placement of the pens in tidally flushed waters.

Waste Space

A weak contender today for coastal ocean space is industrial and domestic waste accommodation. Since the early 1960s with the publication of Rachel Carlson's "Silent Spring", there have been increasing pressures from environmental groups and regulatory agencies to keep all societal discards out of the marine environment. They have effectively created the perception that the oceans can accept no wastes without the possibility of resource loss. On the other hand, social and natural scientists and engineers have shown that comparisons of disposal sites (air, sea and land) for a given waste in a given region do not a priori exclude the oceans but, in fact, in some cases favor it.

But in the foreseeable future the arguments of those who seek a totally undisturbed ocean will weaken when confronted with economic forces. First of all, the available land for waste disposal is running out near populated areas (especially those along coasts). In the United States, domestic wastes are shipped across state boundaries, e.g. from New York and New Jersey to Pennsylvania and Ohio. For hazardous wastes the situation is even more disturbing. California's more stringent regulations on hazardous waste disposal, compared to federal ones, have driven in-state disposal costs to $261-$1,101/ton. On the other hand, wastes can be transported to other states such as Utah, for disposal costs of $142/ton. Utah and other states receiving California's toxic wastes are reacting by both restricting the amounts that they are willing to take and by proposing increased fees.

A return to ocean waste disposal will come about as scientific and engineering judgements dominate the policy decision processes and displace perceptions often emotionally conceived. Where the economic, social and scientific aspects of land and air disposal (incineration) are dispassionately compared with those of coastal ocean disposal, a reappraisal of marine space for some accommo-dation of wastes will most likely appear. Whether ocean disposal through discharge from ships or from pipes becomes the preferred strategy, the amount of coastal zone space required for the land or sea activities will be small.


Improved and expanded harbor facilities for an increasing trans-oceanic world trade underlay the needs of another coastal zone space activity. The rising world population is demanding more materials and energy to achieve higher standards of living than those now enjoyed. For those countries producing or requiring the importation of high volume, low cost commodities such as coal, oil timber and grain, large bulk ocean traversing carriers (150,000 dead weight tons) may be economically reasonable. At the present time such vessels, the supertankers, are primarily involved with the transport of petroleum and petroleum products. For example, shifting industrialization in the Mediterannean from northern to southern and eastern countries will emphasize the need for improved harbor facilities. Steel production in northern European countries will probably decrease in the near future as a consequence of competition from the outside and a decreased need for smokestack industries. Countries in the south and east Mediterranean, as a part of their industrialization, will develop their activities with the importation of iron ore and coal. Large vessels will probably be employed and will enter ports that have appropriate ship and cargo handling facilities. But the shipping industry clearly will seek more harbor space in southern and eastern Mediterranean countries.

Usually harbor improvements required to handle the larger vessels consist of deepening channels and involve extensive and continuous dredging. Alterations to life processes in and surrounding the port area can be expected. Fishing and fish nursery grounds may be changed or eliminated. The dredging itself can interfere with sediment transport processes. Finally, increased ship loading and unloading can place additional stresses upon the port vicinity through entry of alien materials and non-indigenous organisms to the waters.

Some Other Competitors

There are other minor competitors for coastal ocean space from the mining, energy and fishing industries. They are in various states of development; some may expand their activities markedly.

Energy: The continuous recovery of energy from the sea remains elusive although it is often featured on television, radio and the printed page. The economics of the construction of appropriate structures are formidable. Still, advocates of the various schemes remain unperturbed. They are especially encouraged by the argument that the three promising technologies, ocean thermal, tidal and wave energy conversion, do not contribute greenhouse gases to the environment.

The most notorious of the schemes, ocean thermal energy conversion (OTEC) utilizes the temperature difference between warm surface and deep cold waters to run a turbine in closed or open cycles. The geographic zone in which OTEC is plausible centers on the equator and extends to the north and south by about twenty degrees of latitude. Only three developed nations are within the belt: Australia, Japan and the United States. One basic requirement to bring OTEC into competition for coastal ocean space is the construction of a successful prototype in the range of 1 to 50 megawatts. Secondly, the ability to utilize the energy generated at the OTEC site must be demonstrated.

Energy can be drawn from the gravitational forces exerted by the moon and the sun upon the earth - the production of ocean tides. A straightforward way to harness tidal energy involves placing a barrier with sluices and turbines across a marine basin.

There is one successful operating plant at the mouth of the river Rance in Brittany, completed in 1967 with an output of 240 thousand watts. Smaller plants have been built in China, Canada and the Soviet Union. There are probably thirty sites in the world that can be successfully employed for the generation of tidal energy.

There have been many ideas to harness the kinetic energy from waves but today most devices involve the compression of air which is used to run a turbine connected to a generator. Japan and Norway appear to be at the forefront of wave energy activity with the United Kingdom not far behind. The former countries have successfully demonstrated pilot models.

Fishing: The need for U.S. coastal ocean space by the commercial fishing industry has been decreasing over the past years. Although the demand for marine food products has been rising, a number of factors combine to lessen the requirements for support facilities in the coastal zone. First of all, there are the changes in fishing techniques, the small fishing boats have been replaced by larger vessels, the catcher/processors, which require different but overall less space. Secondly, mariculture products are successfully competing with products from the wild and are increasing annually. Finally, overfishing is reducing the availability of desirable species and the physical alterations of estuaries and wetlands are decreasing the areas of the breeding and nursery grounds.

Mining: Of the solid minerals extracted from the coastal zone, two important groups are seasalts and sand/gravel for use as aggregates. The latter are used in the production of concrete, beach replenish-ment, roadfill, landfill and the construction of artificial islands. In addition there are placer minerals, which have been beneficiated from the sediments and include gold, titanium oxides, phosphites and chromites. The largest exploitation of sand/gravel from coastal areas takes place in Japan and Great Britain. The needs of all countries for sand and gravel are increasing. The mining can impact upon fish nursing and breeding grounds. There is interference from such activities in erosional processes and in the maintenance of submarine cables and oil/gas pipelines.

Sand and gravel from the sea compete with their land-based counterparts. Distances from the quarry site to the use site are ever increasing in developed areas. The relative transport costs of land and sea sand and gravel, coupled with the qualities of the materials, will determine to a major extent which source will have the competitive advantage. In some cases the rental of shore space for marine activities will enter the financial picture.

New Directions

In the last decade of the twentieth century, social and political changes are reordering priorities for coastal zone space occupancy in many of the eastern European countries. Expenditures for military activities with its associated space needs are on the downswing. This has been exemplified by recent developments in the Soviet Union and in the new countries that have replaced it. In the post-World War II period of the 1970s and the 1980s, military usages and the engineering research to support them were given the highest priorities for coastal ocean space. These were followed by living resource utili-zation to satisfy the increasing need for animal protein. Recreation, tourism and environmental protection had the lowest priorities. As the social and economic patterns stabilize, there will evolve a new distribution of space with touristic activities, which can attract hard currencies from the west, rising to a position of greater importance than it enjoyed in the past.


The demands for coastal space will clearly be in excess of what is available. Besides tourism and recreation, mariculture, waste space, transportation and the lingering military, there are some minor players: energy development, coastal mining and the declining fishing industry. All have their patrons in legislative and executive parts of governments. If the past is a guide to the future, the scientific and engineering communities will have but a small say in the allocation of any available coastal space. Economics and social pressures will prevail. Still help from the scholars will help maintain and improve coastal zone quality.

A few countries are taking steps to minimize use conflicts. France, Italy and Spain are taking inventories of existing and potential resources with the goals of a balanced development. For example, forty-two percent of the 8,000 km. of coastal zone in Spain is as yet unoccupied and new laws and policies have been formulated to minimize unregulated development. The new policies define the coastal strip as being part of the public domain with limited access. Similarly, Israel's 190 km. coastal region is to a large extent unoc-cupied or used for activities that do not have to be in the coastal zone. Throughout the world, the increasing demand for expanded recreational activities are directing environmental agencies to formulate regulations for the protection of coastal resources.

Table 1: The Contributions of Tourism to the Economies of some OECD Nations

(OECD, 1989)

United States		Six percent of GNP, US$293 billion
			Includes residents and international visitors
Canada			Four percent of GNP
United Kingdom		Four percent of GNP, greater than 9 billion pounds
Switzerland		6.2% of gross domestic product
			16.9 billion Swiss francs
Turkey			Three percent of gross national product
			2 billion U.S. dollars
Yugoslavia		Ten percent of foreign exchange earnings
Portugal		Nine percent of gross domestic product
Norway			3.3% of total gross product
			NKr 36.8 billion
New Zealand		3.9% of gross domestic product
			NZ$2.3 billion
Italy 8.0% of gross domestic product 70-75 billion lira Germany 4.6% of national income 96 billion DM France 390 billion French francs Finland 40% of export of goods and services MK 4.1 billion __________________________________________________________________________
Table 2: World cruise population (OECD, 1991)
In thousands)
Cruise Area 	1984 	1985 	1986 	1987 	1988

North America 	1,630 	1,950 	2,340 	2,730 	3,200
Europe 		  220 	  250 	  200 	  300  	  330
Other 		  150 	  160 	  160 	  170	  190

Total 		2,000 	2,360 	2,700 	3,200 	3,720
Growth Rate (%)	-	 18.0	 14.4	 18.5	 16.3
Table 3: FAO Aquaculture Species Production 1988

Category 				  Metric Tons

Carps, barbels and other cyprinids*.........4,589,078
Tilapias and other cichlids...................264,535
Miscellaneous freshwater fishes.............1,071,680
Sturgeons, paddlefishes...........................205
River eels.....................................99,080
Salmons, trouts, smelts.......................459,233
Miscellaneous diadromous fishes...............349,298
Flounders, halibuts, soles......................3,280
Cods, hakes, haddocks...............................7
Redfishes, basses, congers.....................53,795
Jacks, mullets, sauries.......................187,120
Herrings, sardines, anchovies.......................3
Tunas, bonitos, billfishes.........................47
Miscellaneous marine fishes....................34,236
Freshwater crustaceans.........................59,650
Sea-spiders, crabs..............................3,303
Lobsters, spiny-rock lobsters......................90
Shrimps, prawns...............................511,454
Miscellaneous marine crustaceans...............33,941
Freshwater mollusks.............................2,130
Abalones, winkles, conchs.......................1,598
Scallops, pectens.............................305,529
Clams, cockles, arkshells.....................456,592
Miscellaneous marine mollusks.................284,609
Frogs and other amphibians.........................20
Sea-squirts and other tunicates................32,519
Miscellaneous aquatic invertebrates...............427
Pearls, mother-of-pearl, shells...................212
Brown seaweeds..............................2,366,994
Red seaweeds..................................850,020
Green seaweeds and other algae..................8,670
Miscellaneous aquatic plants..................406,597

*Includes catfish

FAO Fisheries Circular No. 815 Revision 2

Table 4: Aquaculture Production by Region and Country 1988

(Metric Tons)
Region		  countries Finfish Crustacea  Mollusca   Seaweeds  Others

Africa, North & NE     4     57,733        2        530          0       0
Africa, S. of Sahara  34     11,328       75        232          0      50
North America 	       2    260,160   30,675    131,888          0
Central America        8      9,333    8,612     52,031          0       0
South America         12     22,326   87,928        316     23,109       0
Caribbean             12     17,053    1,343      1,541          4      30
Europe                29    472,008    3,042    621,432          0       2
USSR                   1    359,549        0        234      5,000       0
Near East             11     33,455       13          0          0       0
Oceania               10      3,989      564     34,700        629     140
East Asia             10  4,863,142  337,271  2,114,958  3,526,077  33,781
West Asia             11  1,004,521  142,675    115,343     77,462      20

TOTAL                     7,114,597  612,200  3,073,205  3,632,281  34,023

Percentage of World Total     49.2      4.2       21.2       25.1     0.2
(Source: FAO, Aquaculture Minutes, Number 8, August 1990: taken from A. G. May, 1990).

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