Soils from the Sudbury region, Canada, which have been contaminated by the heavy metals nickel, copper, cobalt, and iron, from airborne smelter emissions, have been assayed for their toxicity to seedling growth. The extent of radicle elongation in bathing solutions of soil-water extracts has been used as a bioassay index of soil toxicity. The root growth of four species was reduced in extracts of soils which had been collected up to a distance of 49.8 km from the Coniston smelter. Inhibition was greatest in surface soils. Water extracts had metal concentrations of up to 142 ppm Ni, 59.5 ppm Cu, and 4.6 ppm Co. In addition, aluminium occurred in water extracts at 50.6 ppm at 0.8 km from the smelter, and up to 98.9 ppm somewhat farther away, even though it was not smelted in the region.

All of the four metals nickel, copper, cobalt, and aluminium, were shown to be markedly inhibitory to seedling growth at concentrations below 5 ppm. In addition, all of the metals tested were concentrated markedly in the seedlings, expecially in their roots. The concentration factor was often 50- to 100-fold that of the bathing solution. Nickel appears to be the greatest single heavy-metal problem with which the vegetation has to contend. Even in the event that the major emissions of sulphur dioxide in the area be controlled, the concentrations of the toxic heavy metals nickel and copper already existing in the soils over many square kilometres present severe problems for seedling establishment and, consequently, revegetation.

Northern Africa is rather poor in national parks and nature reserves in comparison with equatorial and southern Africa. The remaining populations of nomadic ungulates in the Saharan region are difficult to protect within the boundaries of national parks, if only because they are nomadic and move over great areas in an irregular pattern owing basically to the erratic rainfall. It ought, however, to be a conservation priority for many countries of northern Africa to make an effort to conserve desert and subdesert antelopes of various species before it is too late, because these animals are so productive and thrive in areas with meagre vegetation and no surface water for long periods. They are an excellent renewable resource of the deserts!

In northern Africa only a fraction of the former herds of wild ungulates still survive in declining numbers, whereas in southern Africa a semi-desert country such as Botswana still harbours important herds of many herbivorous species. But also in Botswana their numbers are declining drastically in comparison with the situation only about fifteen years ago, though, fortunately, several large reserves have been established in that country during recent years. This is also the case in most other countries of southern Africa.

Madagascar and the Mascarene Islands also share similar conservation problems with continental Africa, but in these areas with a high proportion of endemic plants and animals the human overexploitation tends to have more serious and immediate effects on the biota than is the case on the African mainland.

The present conservation needs of Africa include more national parks and other protected areas. These are of fundamental importance for environmental conservation, being in effect in many regions the only major areas where the environment of today and even of the past may be preserved.

Human population growth is clearly outstripping the possibilities of increasing the supply of food and other prerequisites for satisfactory existence. Already, with around four thousand million people on Earth, the race appears to have been lost by agriculture. The prospect of doubling this population by shortly after the turn of the century is bleak indeed. It is the belief of many, however, that zero population growth will be reached earlier by a catastrophic increase in the number of deaths—most probably from starvation. This also bodes ill for conservation; for as people get more and more hungry, their behaviour towards wildlife and what remains of the natural environment is going to become more and more reckless. The destruction of both wildlife and its habitat may be expected to extend to quite devastating proportions, which will require understanding action in both over- and under-developed countries to counter with any degree of success.

Man is inexorably changing the face of the Earth and weather patterns in directions which could have all manner of widespread ill-effects, and already have had some catastrophic local ones. Yet more and more of the world's productive lands are being paved with concrete, and the productivity of even wider areas is being permanently lost through erosion and laterization following the clearing of forests and other binding vegetation. Simultaneously, many strains of crop plants are being lost which are essential to humanity because they enable plant breeders to develop new agricultural varieties to help keep abreast of changes in pests and weather, and to raise production levels.

Conservation organizations have been primary forces in the establishment of wilderness areas throughout the United States. They have also been actual participants in wilderness recreation, particularly through sponsored trips. Preliminary results indicate that these trips have a tremendous impact on the wilderness resource because of the large-size parties, sedentary camping habits, and the large amount of bulky tentage and equipment employed. Basic policy changes are suggested as a means of protecting the wilderness landscape.

This paper describes the effects of 1,020 passages of snowmobiles, made over two winters, on three regularly winter-snow-free alpine tundra plant communities. A cushion-plant community on a 7-degrees slope showed a 31% reduction in total living plant coverage due to snowmobile impact. Destruction was greatest to soil lichens, rock lichens, and the cushion-plants Arenaria obtusiloba, Arenaria fendleri, Paronychia sessiliflora var. pulvinata, Silene acaulis, Eritrichium aretioides, and Phlox pulvinata. Graminoids generally survived to increase in importance. On a flat site, a cushion-plant community with Kobresia myosuroides as its most important species, showed the greatest loss of living-plant coverage, namely 46%. This was due primarily to the destruction of Kobresia, although Selaginella densa, Arenaria obtusiloba, Hymenoxys acaulis, and Eritrichium aretioides, also showed heavy losses. In a Kobresia turf community, destruction was decidedly less severe than in the cushion-plant communities, reduction in total living plant coverage being only 19%. It is suggested that the closed nature of the Kobresia turf, with its stiff tussocks, enables it to absorb impact well. It is recommended that snow-mobile travel be confined to Kobresia or similar turfs, when such travel is necessary under snow-free conditions.

Nuclear fission reactors are widely regarded as the chief energy source of the future. This article holds that the hazards of such reactors, in comparison with other prospective energy sources, are unacceptably high. The biological effects of ionizing radiations, as analyzed in the recent BEIR Report (1972) of a committee of the U.S. National Academy of Sciences, are briefly reviewed; the effects include genetic mutations, induction of cancer, and developmental abnormalities. Hazards are encountered at many stages in the process of nuclear power production: in the mining and processing of uranium, in the design and operation of the reactors, and in the handling, shipping, and storage, of the huge quantities of radioactive wastes produced by the reactors. Grave questions have been raised concerning the safety of the emergency core-cooling systems of present reactors; and the planned breeder reactors, which will contain great quantities of plutonium-239, are likely to be even more hazardous. Storage of radioactive wastes, away from all risks of environmental contamination, in order to be acceptable must be secure for about half-a-million years. No place on Earth has yet been found for which such safety can be guaranteed. Hazards of theft, sabotage, and war, are formidable threats to the future of nuclear fission power.

Use of fission power is not compulsory; present supplies of coal are adequate for two or three centuries, though its mining and use will require drastic steps to protect the environment, thereby raising costs. Alternative, and far less dangerously polluting, sources of large-scale energy production exist or can be developed: notably solar energy and probably nuclear fusion, where intensive research gives high promise of adequate systems for large-scale energy production within 20–30 years. Geothermal energy, though more limited in amount, is also promising. Great savings can also be made by reducing the extravagant use of energy, especially in such countries as the United States; and various conservation measures are indicated.

The deterioration of the physical environment in many metropolitan areas is a fact of modern life. In the United States the traditional alignment of power and institutions have proved to be ineffective in coping with environmental problems. Obvious as is this disparity between the nature of regional environmental management problems and the administrative machinery established to remedy it, too little serious effort has been made so far to do better.

The six experiments described here represent an effort to expand the environmental data-base, to improve the capacity of elected officials and their civil servants to anticipate better the consequences of a variety of environmental decisions, and to provide the broadest possible range of contributing citizens—so that environmental decision-making can become truly participatory. All of the regions involved have so far enjoyed more success technically than in the matters of transfer of information and improving citizen participation.

Soil, moss, and conifer twig and needle, samples were collected along an urban-suburdan transect in Connecticut. All samples were analyzed for mercury content. In general, both the mosses and tree tissues contained higher concentrations of mercury than did the soil. Except for the plant samples collected at the origin of the transect adjacent to an electric generating facility, where the mercury in a moss exceeded that in a Juniperus virginiana tree, the floral components that were sampled proved comparable. Moss sampling would probably give the more reliable indication of urban-industrial mercury contamination.

Since the passing of the Mineral Workings Act 1951 there have been (1) changing pursuits in agriculture and improved methods of restoration, (2) continually rising costs of machinery and labour, and (3) nationalization of the steel industry.

Recently, a new Act was passed, namely the Mineral Workings Act 1971, to make further provision in relation to contributions to and payments out of the Ironstone Restoration Fund, and to abolish the Advisory Committee on Ironstone Restoration. This Act necessited new regulations as follows:

Statutory Instrument 1972 No. 210:

‘This Order prescribes the full and reduced rates of contributions to be paid by ironstone operators towards the Ironstone Restoration Fund under section 1 of the Mineral Workings Act 1971, in respect of ironstone extracted on or after 1 April 1971 and the sum which may be deducted from payments made under mining leases and mineral rights orders (in accordance with section 3 of that Act) in respect of full-rate contributions.’

Statutory Instrument 1972 No. 211:

‘Section 9 of the Mineral Workings Act 1951 provides that the rate of payments out of the Ironstone Restoration Fund to be made to ironstone operators in respect of the restoration of worked ironstone land in compliance with conditions of a planning permission shall represent the amount by which the estimated cost per acre of the work of restoration exceeds such sum per acre as the Minister may determine to be the standard rate. The Ironstone Restoration Fund (Standard Rate) Order 1955 determined that rate to be £110 per acre.

This Order made under section 3 of the Mineral Workings Act 1971 prescribes a new rate of £260 per acre in respect of all work completed after 31 March 1972.’

The conservation movement in Africa during the 1960s has worked along many front lines. Failures and successes have been registered. As a whole one may say that there has been tremendous progress for conservation in Africa when the situation in 1974 is compared with what it was in 1960, but nevertheless at present there are still more productive waters and land areas that are being destroyed than are being saved or restored. The conservation fight has to go on, and it is a battle against time and human misconceptions. Particularly are there some countries in which the values of menaced Nature have been considered to be of such exceptional importance that special efforts have been undertaken within the meagre means available to the international organizations most concerned.

The present paper constitutes a review of significant environmental conservation measures, proposals, and failures, in various regions and countries of equatorial Africa. It is hoped to follow with a similar treatment of northern and southern Africa. Emphasis will be laid on national parks and nature reserves, because at present it is particularly in this field that African states show their conservation consciousness. It is to be hoped that the time will soon come when the necessity for conservation, management, and wise utilization, of renewable natural resources, will be fully realized also outside the national parks and equivalent reserves.