National park managers have to make difficult and often controversial decisions regarding how best to protect parks' resources and provide for their continuing use and enjoyment. Strictly speaking, resolution of parks' problems must be based on whether the NPS is adhering to its legislative mandate to regulate development and use and to protect parks' resources. The most basic fiduciary duties of the NPS are to manage resources in natural conditions, provide for use and enjoyment, and provide benefits for present and future generations. However, neither the legislation, judicial interpretations, nor the NPS, has defined the terms natural, appropriate forms (values) of use and enjoyment, or how to resolve intergenerational conflicts between present and future generations. Because neither scientific standards nor criteria of appropriate use have been defined, the NPS traditionally has fashioned policy by compromise—to reflect different citizen constituencies with preferences for different and often conflicting values.

Developing nations have yet to enter the projected main phase of their population explosion. Between 1950 and 1985 they increased their numbers by 1,980 million people, whereas between 1985 and 2020 the increase is projected to be 2,783 millions. If we exclude China from the reckoning, on the grounds of that country being well on the way to a zero-growth population, the figures are 1,486 millions and 2,415 millions.

The interest in the wetlands ecosystems on Calcutta's periphery should be understood in the context of the search for development alternatives—for locally-adapted, appropriate modes of development rather than transplantation of alien models. Too often, planners look abroad for ideas without realizing that appropriate principles and practices are present in their own backyards. We are now coming to understand that ecodevelopment entails bringing together creative techniques with the ways in which people perceive and approach the issues of quality of life through environmental changes that are in the forefront of planning debates. Human and ecologically-sound planning requires an integration of such understanding with suitable techniques and procedures.

The Country Parks programme in Hong Kong has been overwhelmingly successful in generating outdoor recreational demands. Most visitors concentrate in designated barbeque-picnic sites of which many have been badly damaged by intensive recreational use. The conditions in 60 sites in a popular Country Park were evaluated by allocating ordinal ratings to 20 soil-erosion and site-attractiveness indicators. Index sites representing three levels of impacts were studied in detail for specific changes in vegetation and soil that had been induced by trampling. The magnitude of site degradation was indicated by the relative proportions of vegetation, organic litter, and bare ground, covers. The conversion from vegetation to litter was faster than that of litter to bare soil initially, but the converse is true at advanced stages of degradation. Seven out of fourteen site-attractiveness attributes, including accessibility, facility provision, shape, stocking rate and distribution pattern of facilities, on-site naturalness, and scenic diversity, were associated with erosion–in most cases positively.

The ever-increasing amount of marine debris in the Southern Ocean gives cause for concern, but the subject is little studied. I surveyed beaches on Tristan da Cunha, Inaccessible, Gough, and the Prince Edward Islands, in the African sector of the Southern Ocean, for stranded artefacts during 1984. The types of debris, their origin, and probable fate, were recorded and are reported in this paper.

Whereas it used to be supposed rather widely that fuel-wood was used mainly in rural areas, large-scale migration of rural people to urban areas, and the consequent mushrooming growth of squatter settlements in urban areas (cf. Fig. 4), have increased the consumption of fuel-wood in those areas. The shortage of fuel-wood coupled with the increase in demand, has caused steep rises in the price of fuel-wood in urban areas. Although a large number of studies on deforestation have appeared, the actual forces behind deforestation have been very poorly understood in most of the developing countries (Hadley & Lanly, 1983), while information of where fuel-wood is actually consumed is not widely available. If deforestation is really to be arrested, comprehensive studies on the demand and supply of fuel-wood will have to be generated and concomitant action ensured.

Sudan is one of the African countries that are most seriously stricken by drought, desertification, and famine. Although accurate assessment of the disaster is yet to be documented, published data indicate that some 40% of the human population have been affected. In the Kordofan region alone, some 2.8 million people were subjected to the famine and half-a-million died. The drought's incidence and effects in western Sudan decreased from the Desert zone southwards across the Sahelian zone to the Sudanian zone.

Lowland forest in southern Somalia is restricted to the Holawajir depression and banks of the Jubba and Shabeelle Rivers. Riverine forest probably covers less than 3,000 ha and is undergoing rapid clearance for farming, so that it seems unlikely to survive this century. Further biological survey is required but the flora, and bird and mammal faunas, appear to be impoverished compared with those on the lower Tana River in Kenya.

A method is described of applying institutional arrangements to an individual environmentally significant area (ESA). It is assumed that an ESA has been recognized by park, wildlife, or other groups, on the basis of abiotic, biotic, and/or cultural, characteristics, as well as judgements about significance and constraints. National park, wildlife reserve, or other, institutional arrangements, may also have been suggested for the ESA. The goal is to decide whether these or other arrangements are appropriate— through analysis of relevant: (1) legislation; (2) agencies; and (3) reserve designation or land management types.

Relationships between sedimentation, submergence, and deterioration, of a Mississippi River deltaic-plain coastal wetland forest were investigated. Measured sedimentation rates (0.63 ± 0.35 cm per yr) as determined by 137Cs-dating were considerably less than the rapid increase in water-level (c. 1.36 cm per yr). Transplanted seedlings of Quercus lyrata (Overcup Oak) and of Taxodium distichum (Bald Cypress) survived only on the most elevated natural ridge in this swamp-forest.

The subdivision of Australian tropical rain-forest into one- and two-hectares' residential blocks changes the local ecology in a dramatic manner. It opens the canopy, changes the humidity regime, decimates ancient climax vegetation, and introduces weed species. As a result, the practice is incompatible with the objectives alike of the World Conservation Strategy and the National Conservation Strategy for Australia. Government intervention will be required if the Strategy is to be implemented. The first step towards implementation is the evaluation of current and proposed practices. A brief analysis of the incidence of costs and benefits demonstrates the skewed distribution which results from rain-forest subdivision. A few sellers and promoters receive millions of dollars in capital gains, while millions of other people lose the public and recreational benefits offered by the existing rain-forest, and the world as a whole loses much of scientific value. The information gained by this brief analysis provides the Government with a better basis on which to act than heretofore.

The forest canopy, biomass, and basal tree-trunk cover, of an area of about 200,000 ha, comprising 10 subcatchments in the Indian Central Himalaya, were mapped by employing aerial photographs and non-destructive field sampling. This method provides basic information on the current forest land-use and biomass for enlightened environmental planning and conservation. Regression equations developed to describe predictive relationships between crown-cover and basal tree-trunk cover; biomass and crown-cover; basal tree-trunk cover and bole biomass; and basal tree-trunk cover and total above-ground biomass, for different forests occurring in the area, should prove of value for future ecological studies in the Central Himalaya.

In November 1983, the construction of the first part of an assembling plant of jackets to support oil-drilling platforms began at Punta Banda estuary, a 16.40 km2 coastal estuary located 150 km south of the USA-México border. The area that is being built on (0.45 km2) is located at the south-west corner of the estuary and is delimited by a dike. The second part of the construction, covering a further 0.40 km2, will extend to the south-east and will require some deflection of the main circulation channel.

The endemic Hawaiian biota, having evolved in nearly complete isolation from continental organisms, and lacking as it does many major continental groups, is highly vulnerable to introduced ungulate herbivores, vertebrate predators, predacious and parasitoid insects, predacious snails, and yet other animal and plant groups. Although most of the Hawaiian lowland biota has been obliterated by Man and his introductions, relatively intact ecosystems survive at higher elevations in Hawaii's national parks and elsewhere. Long-term survival of these native ecosystems will depend largely upon the quality, intensity, and endurance, of continuing active management.

The rocky shore of central Chile is heavily harvested by mariscadores de orilla and skin-divers, but their catches are not considered in the fishery statistics. The aim of the present paper is to estimate the intensity of human predation and annual catch of each of the species taken at Las Cruces, Central Chile. The activity pattern of both categories of collectors demonstrate a temporal grouping. The observation of mariscadores de orilla and skin-divers in 3 sectors of fringe totalling 1,500 m of rocky shore during 12 months allowed us to estimate the annual catch per species caught (kg per year).

Closed (or ‘blind’) estuaries are common features, practically throughout the world, of areas experiencing markedly seasonal rainfall. The Bot River vlei is a closed estuary which faces considerable problems of management and conservation. For the past 100 years or more, the estuary has been opened to the sea every 2 to 5 years by artificial means. This has resulted in a very great variability of physical conditions and a concomitantly low diversity of organisms that are able to occupy the estuary permanently. Nevertheless, those species that do exist in the Bot River vlei are mostly estuarine species.