38

There are other sources of waste in Puget Sound, and the Conference (FWPCA, 1967; FWPCA & WSPCC, 1967) went into some detail in considering them. Cities represent a significant source of pollution through various types of sewage treatment plants (or lack thereof). Again the system is at work in recommending that the State require all cities to come to the same level of effective sewage treatment and discharge. It is more difficult, however, to get cities to act, because there is a problem of financing the improved facilities; they are lagging behind industry in the area of pollution abatement. Nevertheless, significant progress is being made. Bellingham, for example, expects to have a complete sewage treatment plant in operation by 1973 that will meet the recommendations of the Conference.

It is important to note in closing that the success of pollution control includes not only the various pulp- mills, but also all other sources of pollution in Puget Sound. In Bellingham, the success of pollution control imposed on the pulp mill ultimately relies on the success of the sewage treatment plant. An agreement should be reached between Georgia-Pacific and the city, so that the 20 per cent SWL that Georgia-Pacific does not intercept will be diverted to the city sewage treatment plant. From there it will be discharged through a diffuser into sufficiently deep water with good currents, to ensure that its biological degradation will be adequate to meet local requirements. Addition- ally, after installation ofa clarifier to remove particulate wastes (recommendation l a, Table III), Georgia- Pacific can divert those particulates that escape the clarifier into the city sewage lines, where they will be diverted to deep water. The sludge beds in Bellingham

Biological Conservation

Bay can then be dredged as the first step towards recovery of the bottom of the bay.

This Conference (FWPCA, 1967) represents a systems approach to a pollutional problem, with requirements applied so that all components of the system will be brought to the same level of biological health. This is mutual coercion on a grand scale; it has been mutually agreed to on a grand scale because the residents of Puget Sound are concerned about their environment. Fortunately, the conscienceless use of Puget Sound as a 'common' for waste discharge from pulp mills has ceased; Puget Sound is now being treated as a common resource to benefit all who are concerned, with strict limitation on those who act without conscience towards it. Hardin's thesis is correct; the system will work if men strive to find the common ground for agreement.

References

CROWE, B. L. (1969). The tragedy of the commons re- visited. Science, 166(3909), pp. 1103-7.

FEDERAL WATER POLLUTION CONTROL ADMINISTRATION [as FWPCA] (1967). Pollution of the navigable waters of Puget Sound, the Strait of Juan de Fuca, and their tributaries and estuaries. Conference Proceedings, Second Session, 6--7 Sept. & 6 Oct. 1967. US Dept of the Interior, Portland, Oregon, 3 vols, 618 pp.

FWPCA & WASHINGTON STATE POLLUTION CONTROL COMMISSION [as WSPCC] (1967). Pollutional effects of pulp and paper mill wastes in Puget Sound. US Dept of the Interior, Portland, Oregon, 473 pp., plus Summary and Recommendations, pp. i-xxii.

HARDIN, G. (1968). The tragedy of the commons. Science, 162(3859), pp. 1243-8.

Mangroves v. Tidal Waves*

In Dacca, East Pakistan, in 1964, the UNESCO Humid Tropics Programme held a symposium on scientific problems of tropical deltas (UNESCO, 1966). An outstanding feature of this meeting was a steamer trip through the Sunderbans, the famous mangrove swamps that occupy the lower portions of the Ganges

* On hearing of the contention which has been voiced in some conservationist circles that last year's tidal-wave disaster in East Pakistan would, at the worst, not have cost nearly so many tens of thousand of human lives and so much devastation if Man had not removed very widely the local mangrove vegetation, we asked two of our Consulting Editors to comment on this apparent ecodisaster and are now privileged to publish their views. Dr Fosberg has had possibly uniquely wide and protracted experience of maritime situations practically throughout the tropics, and Professor Chapman has recently completed a book in manuscript on the mangroves of the world.--Ed.

Delta. This gave the participants a chance for lengthy informal discussion on many subjects that were not on the formal agenda. During examination of the mangrove swamps and of the extensive clearing then under way, followed by conversion into paddy fields, many questions were raised as to the possible con- sequences of this clearing--including the effect of storm damage. It was suggested by several participants that the mangrove forest is the best available protection against the ocean surges that are generated by hurri- canes. Unfortunately this suggestion, made informally, never received adequate discussion, and did not appear in the volume of proceedings.

The situation of the Ganges Delta, at the head of the funnel-shaped Bay of Bengal, poses perhaps the most serious threat from surges driven by storm waves to be found anywhere in the world (except on low coral

Fosberg and Chapman:

atolls). The Sunderbans--a vast, broad belt of man- grove in the part of the Delta facing open water-- impressed at least this symposium participant as a made-to-order set of baffles to slow down the waters that would be driven landward by a storm in the Bay of Bengal. Extensive clearing, even though it might increase rice production, might also expose the popula- tion to unprecedented floods (Smithsonian Institution, 1970).

Although full information has not been available to me as to how far the clearing had been completed or just where the greatest effect of the 13 November 1970 hurricane was felt, I cannot but wonder just what role the clearing may have played in the enormous damage and death-toll. Noakhali District and Chittagong, which are said to have been hardest hit, had, of course, much less mangrove protection than was afforded by the Sunderbans. However, from Hatia Island westwards, the upper Delta was formerly protected by many miles of luxuriant mangrove forest. The fact that in the Patuakhali District there were 65,000 deaths suggests that the mangroves had been removed to fairly close to the seaward margin of the swamps. This clearance was well under way in 1964, when large areas had been converted to rice paddies and many villages were already established.

It is not suggested that the mangroves would have afforded complete protection against 30-foot (9 m) waves, especially in the eastern part of the Ganges Mouth, which has much more open water than is the case farther to the west. However, the fact that from 300,000 to 500,000 people perished in this Delta area is a sobering thought, and justifies consideration, at least, of whether the conversion from mangroves to

Mangroves v. Tidal Waves 39

rice on such a scale and in such a physiographic situation was really wise, after all.

References

UNESCO (1966). Humid tropics research. Scientific problems of the humid tropical zone deltas and their implications. Proceedings of the Dacca Symposium.. . 24 Feb.-2 March 1964, UNESCO, Paris, 422 pp.

SMITHSONIAN INSTITUTION (1970). Report of Event 100--70, Nov. 16-30, 1970. Smithsonian Institution, Centre for Short-Lived Phenomena, Cambridge, Massachu- setts.

F. R. FOSBERG, Smithsonian Institution, Washington, D.C. 20560, USA.

Mangrove vegetation forms an effective protection belt to land lying behind it and normally prevents erosion. The removal of mangrove, whether in part or in whole, would clearly remove protection from high tides and severe waves. The presence of a substantial mangrove belt would reduce wave action, and water would spill more calmly over the land. Even mangrove, however, cannot stand up to strong winds of gale or hurricane force. There are documented cases of this throughout the West Indies. High seas accompanied by gale-force or hurricane winds could therefore destroy a mangrove belt, and under such circumstances any protection they might afford would be lost.

V. J. CHAPMAN, Professor of Botany, University of Auckland, Private Bag, Auckland, New Zealand.

European Working Conference on Environmental Conservation Education

The establishment of a continuous and sustained programme of environmental education relevant to contemporary needs in various European countries is the basic objective of a working conference which is being convened by IUCN (through its Commission on Education). The Conference is being held in the Gottlieb Duttweiler Institut at Rfischlikon, Switzer- land, during 15-18 December 1971. The World Wildlife Fund International, the WWF Swiss National Appeal, and some other Swiss organizations, are participating in the financing of this project.

Special attention is being focused on the introduction of appropriate environmental education into school curricula and teachers' training, as well as on environ- mental education programmes in south European countries. It is expected that the Conference will launch intensified developments and concrete projects in this field in many European countries, as well as engender their international cooperation. Coordinator of the Conference is the Education Executive Officer, IUCN, 1110 Morges, Switzerland, from whom further details may be obtained.