Let us return to people and food, and another simple equation. The number of people per hectare of arable land, calculated over large regions, looks like a climatic distribution. I guessed at the form of the equation, calculated what the population per arable hectare was on the basis of climate, and compared it with the situation as observed. The correlation between them is 0.998. (See Fig. 8.) It is an almost perfect relationship. The equation relates population per arable hectare to rainfall and temperature, and ultimately to sunlight and water. If one enters Fig. 9, which is a graph of the equation, with the temperature, and finds the intersection with the appropriate rainfall curve, one can see how many people are currently fed from an arable hectare.

The Galapágos Archipelago is an area of very special significance to ecologists. Its unique flora and fauna, rugged scenery, and historical connections with Charles Darwin, make it a place of environmental pilgrimage. Between 1970 and 1985, visiting tourist numbers, comprised largely of foreign naturalists, grew from negligible levels to about 15,000 per annum. In 1987, visitor arrivals to the Galápagos grew to 32,500 following the opening of a second airport in 1986.

Management of tourism has involved a policy which requires most visitors to be accommodated on boats, places strict controls on the sites which can be visited, and requires tourists to be accompanied by highly-trained Naturalist Guides. The policy precludes development of any substantial island-based tourist infrastructure. Recently this approach has become increasingly inadequate in the face of rapid small-scale, little coordinated, tourist development.

Best Practicable Environmental Option (BPEO) is an invention, peculiar to the British approach to pollution-control, that should have wider application than at present. As the British have developed the idea, BPEO will initially be geared to the mix of residuals emanating from specially-scheduled processes. The aim is so to integrate the residuals' stream that the ultimate environmental alteration is minimized in an optimal but realistic manner. The concept is polluter-orientated—not policy-, planning-, or environmentally-, directed—the aim being so to encase a pollution emitter in a single but comprehensive regulatory envelope that, ideally, best technology, best management, and best science, combine to produce the most efficient and least-offensive discharges.

This paper analyses the genesis of the idea of BPEO, and examines the influence of the growing power of European Community environmental directives on its development and interpretation. For BPEO to work, more fundamental reforms to UK regulatory agencies and legislation will be required. These reforms relate to greater openness and documentation, to a more participatory form of judgement with innovations in economic auditing, and to a more explicit accountability through Parliament and the courts, than are currently practised.

Bureaucracies adapt only slowly, however. So far the British have moved a little way to recognizing the realities of the BPEO approach, but nowhere nearly far enough. BPEO is a philosophy that is close to the practice of sustainable development. Placed in a broader planning and policy context, BPEO has great significance for ecologically-sustainable practices. However, that prospect lies beyond any present proposals for administrative reorganization, and only imaginative experimentation, led by an enlightened and determined private sector, seems at all likely to create the changes in attitude and procedure that would be necessary to incorporate BPEO within a practical programme of ecologically sustainable development.

The ecological consequences of contemporary land-use in the neotropics have important influences on national park management in the region. Historical patterns suggest that major land-use changes have occurred regularly, and that these patterns have recently intensified. Is there a relationship between specific land-uses and specific threats to protected areas? Can this relationship be detected in a population of parks?

In a survey of managers of 183 national parks, 122 returned questionnaires from 19 countries in the neotropics. We found that a range of land-uses, from livestock grazing to quarrying, are occurring in and around the parks. The results of our statistical analysis indicate that many of these activities are associated with specific threats to park resources: for example, poaching for subsistence was statistically associated with each of the ten most-reported threats.

We offer two suggestions for improving our understanding of environmental degradation within parks. First, that research and park management be expanded to acquire a regional focus, namely that the land-transforming activities which threaten park resources can best be understood by incorporating the regional-social and political-economic contexts in the analysis. Second, that the influences of the global economic system be increasingly considered in conceptual frameworks of conservation biology.

The fluxes of heavy-metals, and the fly-ash component magnetite from coal-burning, to sediments of the Lake of the Summer Palace in Beijing, China, have increased measurably over the last fifty years. The excess metal contents and the magnetite are attributed to the combustion of coal.

Even with a doubling of coal usage by the year AD 2000. the anthropogenic metal fluxes in Beijing, China, will still be less than those recorded for recent times in metropolitan Tokyo and US lakes. In principle, these fluxes can be reduced by the installation of appropriate emission controls at the coal-burning facilities.

Effective dissemination of information involves hard work, an ability to write, a sense of timing, some luck, and a capacity to keep things in perspective. More specifically, I think success in publicity and public relations depends on an ability to keep the following considerations or groups of considerations in mind on a regular basis:

1. What is the message or information to be conveyed?

2. Why should this information be shared with others?

What are the real motivations behind the desire to communicate it?

3. What audiences could this information be transmitted to? Which should it go to preferably?

4. What is the best medium to transmit the information? Which other media may also be effective?

5. To what degree are intermediaries required to deliver this information? What are the chances of their misediting the material? Are the risks of a foul-up worth the potential benefits of sending the information through second or third parties?

6. When is the best time to disseminate the material?

7. Can the effectiveness of this campaign be assessed for each target audience? If so, how? If not, why?

Communication is a tremendously complex process. No two people perceive the world in exactly the same manner—nor do they encode or decode messages identically (see Bugenthal et al., 1970). Indeed, the subtleties of communication are so fine that even the most carefully constructed message runs definite risks as it is transmitted from one person to another (see Knapp, 1972). In short, we should probably always assume that others will interpret our message somewhat differently from the way in which we intend it to be received.

This explanatory note is intended to accompany the map included in this issue. The map is on a scale of 1:30,000,000 (1 cm = 300 km) and shows regional-scale ‘ecosystem’ units, or ecoregions, differentiated according to a scheme modified from J.M. Crowley (1967), and using climate and vegetation as indicators of the extent of each unit. The units are similar in concept to ‘ecobiomes’ as proposed by Polunin (1984). The map was developed following a proposal by Bailey & Hogg (1986) to supplement the Udvardy (1975) system of biogeographical provinces with a treatment of higher resolution. Three levels or categories of this hierarchy are shown. Of these the broadest, domains, and within them divisions, are based largely on the broad ecological climate zones following the Koppen system as modified by Trewartha (1968), and summarized in our Tables I and II. Climate is emphasized at the broadest levels because of its overriding effect on the composition and productivity of ecosystems etc. from region to region.

The ever-increasing demands for outdoor recreation have caused widespread ecological damages in many parts of the world, so that methods to contain deleterious impacts and maintain the quality of recreational experience must be earnestly sought. Besides the commonlyprescribed preventive and ameliorative actions on the resource-base, visitor management which can provide cost-effective and long-term solutions deserves more attention than hitherto. This paper evaluates a spectrum of relevant options including the subtle (influencing userbehaviour), through the intermediate (redistributing use), to the regulatory (rationing use).

The reduction of per caput impact can, naturally, raise the capacity of an area to accommodate continuing use. Minimum impact techniques can substantially curtail the largely inadvertent damage due to ignorance rather than malice, while recreational planning and management can take into account the changing user preference. Appropriate data to guide management decisions can be acquired through innovative non-contact approaches, including visitor observation, to solicit candid and spontaneous responses. Good-quality information, conveyed through different channels in ample time before a visit, can effectively modify user behaviour and perception. Formal and informal education, to inculcate a responsible attitude towards the natural environment, can bring long-range benefits. Citizen participation can furnish diversified and useroriented perspectives that are important for successful programmes.

Plant genetic resources are vital in safeguarding and increasing crop production and enhancing human nutrition, particularly in a Man-dominated world. Crop genetic resources are currently under threat of loss for various reasons. Conservation as seed is the most common and practicable method of preserving plant genetic resources. The International Board for Plant Genetic Resources (IBPGR), in cooperation with gene-banks around the world, has created a global network of base-collections. In order to minimize losses of stock in the gene-banks, standards were developed in 1985 and base-collections were assessed against them.

The present study analyses the energy-budget of ‘village ecosystems’ in a dry tropical environment. These systems depend to a great extent on the surrounding natural forest/savanna ecosystems. Accordingly the objectives of the study were to quantify (i) the energy efficiency of rain-fed agriculture at the ecosystem level, and (ii) the indirect impact of agricultural activity on the surrounding forest/savanna ecosystems.

Agronomic output from farming is not sufficient to meet the food-energy requirements of the villagers, hence 27.0 to 51.0% of the requirement is met from outside markets. Operation of the agro-ecosystems involved requires a considerable amount of subsidy from the surrounding forest/savanna ecosystems in terms of fodder and fuel-wood. About 81 to 100% of the fuel needs, and 80–87% of the fodder needs, are met from the natural forest/savanna ecosystems. Thus, for each unit of energy obtained in agronomic yield (including milk), 3.1 units of energy are expended from the surrounding natural ecosystems in the form of fodder and fuel-wood.

The erratic and ill-distributed nature of monsoon rains results in moisture deficit which affects the crop production in dry-land farming, causing partial or total failure of the crops. For achieving increased and stable agronomic production under rain-fed conditions, improved dry-land farming techniques have to be applied. Some of these techniques are: (1) introduction of crops and varieties that would be capable of maturing in a period of 90–100 days, and adequate use of appropriate fertilizers; (2) planned rain-water management including storage of surface runoff; and (3) practices of intercropping with crops of longer duration than those currently grown, having slow growth-rates in the early part of their life-cycles.

An account is given of the unique area comprising Cape St Vincent and the Sagres Peninsula, in southwestern Portugal. It has a variety of plant communities, some of which occur only in this area, and is the home of several endemic plant species. The two promontories are important breeding sites for several bird species, and are a landfall for thousands of migrating birds. Other animal groups of the area are less well-known. The area is subject to increasing visitor pressure, and tourist development is on the increase. The case is pressed for its conservation as a vital ecological resource, and as an asset to Portugal.

The 3,162 sq. km Desert National Park (DNP) is one of the largest protected areas in India. It represents all of the natural features of the Thar Desert in India. Since its establishment in the early 1980s, the wildlife population has increased, and now the Indian Gazelle, the Great Indian Bustard, the Desert Fox, etc., are easily seen in it. But although many core areas of 500 to 1,000 hectares each have been established, progress in the development of the Park is slow, and now the future of the Park itself is in jeopardy owing to a plan to construct a feeder canal of the main Indira Gandhi Nahar (canal) Project (IGNP), which would bisect the Park. It is feared that such improvement in irrigation facilites would make it impossible to shift the villagers outside the Park boundary, as had been planned earlier—and moreover, it would attract settlers to the Park. Salient features of the DNP, its important fauna, and various options to save the Park, are described in this paper.

Military destruction by conventional arms of both terrestrial and freshwater ecosystems is described, with emphasis placed on the effects of World Wars I and II on the territory of the USSR (especially of Russia, Byelorussia, and Ukraine). It is shown that a wide range of serious damage is done in terrestrial natural areas: to forests which may be decimated, to mammals which are commonly killed, and to the land which is extensively disturbed and rendered infertile or even uncultivable. Inland waters, too, are widely disturbed, though numerous new bodies of water may be formed in various ways, while fisheries are commonly disturbed, though ‘Wartime military activities can greatly reduce fish catches, to the benefit of fish populations.’

The linkage between socio-economic change in the Uttar Pradesh (Indian) Himalaya and forest resource condition is investigated through a case-study of Munglori village. Research focused on the village biomass utilization system, particularly fodder- and fuel-flows, as the key link through which socio-economic conditions can be translated into actual forest-use patterns.

In 1984, agriculture and animal husbandry in Munglori was dominantly subsistence-oriented. Rain-fed rice, wheat, and various millets, were the main food-crops. Animal fodder and fuel were derived from a variety of sources near the village, and demand for these resources was dispersed via a seasonal migration-cycle which provided access to resources outside of the immediate village area. This basic pattern of resource use has prevailed in the area throughout historic time, and has led to gradual degradation of forest resources primarily through inhibiting regeneration of Camus Oak (Quercus leucotrichophora), the dominant fodder- and fuel-species.

Lakes Visthonis, Kerkini, and Mikri Prespa, in Greece – Mikri Prespa being designated also a national park – although wetlands of international importance, suffer severe conservation problems with a continuous deterioration of their resources. A major cause of this problem is unsustainable utilization of the wetlands by their main users, local fishermen. The aim of this paper is to present several demographic and fishing-activity characteristics of the fishermen, and to analyse the conflict by associating these attributes with the conservation attitudes towards elements of the wetland ecosystems, the pelicans, and other birds.

Awareness of the environmental implications of different development strategies has grown significantly since the early 1970s. Although much destruction is still being wrought, there are at last hopeful signs that some major multilateral development agencies, governments, and NGOs, are beginning to adopt more environmentally sensitive policies.

Recent advances in environmental and development theory have focused on the concept of sustainable development, arguing that the environment must be seen as an integral part of long-term sustainable development rather than merely as a resource to be exploited or traded for economic development.

This paper reviews recent contributions to the literature on both conceptual and empirical aspects of this topical debate, stressing particularly the ‘Brundtland Commission’ report and the work of Michael Redclift. An historically sensitive political perspective is proposed as most appropriate for embracing not only the more traditional ecological and economic aspects but also the crucial political factors underlying uneven development and underdevelopment in the age of an increasingly integrated global economic system. Although we now have a fairly sophisticated theoretical understanding of sustainable development, appropriate methodologies and techniques for translating this into practice are still required. The paper concludes that a blend of ‘top down’ and ‘bottom up’ approaches would give greatest flexibility, and suggests how the assessment of sustainability at the level of individual agro-ecological systems might be advanced.

The US Department of Energy's Hanford Site, by virtue of its large size of 1,450 km2 (560 mi2) and conservative use of undeveloped land, provides a sanctuary for plant and animal populations that have been eliminated from, or greatly reduced on, surrounding areas primarily as a result of decades of intensive agriculture. This paper describes Hanford Site biota with emphasis on fishes and other animal wildlife that are currently surveyed as part of a continuing environmental monitoring programme.

The United Nations General Assembly, at its forty-second session, in 1987, adopted the ‘Environmental Perspective to the Year 2000 and Beyond’ as a framework to guide national action and international cooperation for environmentally sound development. The Environmental Perspective had been prepared by member governments in response to the General Assembly resolution 38/161 of 19 December 1983, which called for shared perceptions of long-term environmental issues and of the appropriate efforts needed to deal successfully with the challenge of protecting and enhancing the environment, aspirational goals for the world community, and a long-term agenda for action. The Perspective was prepared through a linked process of direct intergovernmental consultation and review, and the preparation by a Commission of eminent individuals, chaired Dr Gro Harlem Brundtland, Prime Minister of Norway, of the report ‘Our Common Future’.

This paper examines the level of environmental security in the Danube River drainage basin: an ecogeographical region covering 800 thousand square kilometres, supporting some 86 million inhabitants, and occupying greater or lesser portions of 12 nations—especially of the 8 riparian nations. The waters of the basin are important, if not indispensable, to the basin inhabitants for various purposes, among them: household, municipal, agricultural, industrial, waste disposal, transportation, power generation, fishing, and aesthetic.

Despite a flow at the mouth of some 6,500 cubic metres per second, the Danube basin waters do not suffice for all of these diverse and sometimes conflicting demands that are placed upon them, this paper outlines the resulting environmental problems—especially those associated with Danubian pollution, habitat disruption, and the generation of hydropower. It refers to the existing legal instruments that address environmental vandalism (especially in time of war), pollution (of both air and water), habitat disruption, and resource utilization (both non-extractive and extractive), noting their levels of acceptance and their lacunae.

To conserve its wildlife, Botswana has set aside more than 17% of its total land area as game reserves, national parks, and wildlife management areas. Despite this generous allocation to wildlife, the fauna of the country is declining in both absolute numbers and species diversity. Lack of permanent water-sources in some game reserves, obstruction of fauna migration routes by cattle fences, and a poorly-developed tourist industry, are partly responsible for this decline.

In a developing country such as Botswana, tourism should yield sufficient funds for the maintenance of game reserves and national parks. But currently the tourist industry accounts for less than 2% of the gross national product. Unless the industry is encouraged to flourish and expand into dormant reserves such as the Gemsbok National Park and Mabuasehube Game Reserve, animals in those sanctuaries are likely to be driven by drought into South Africa.