Over the last twenty years, the population of Mountain Gorilla (Gorilla gorilla beringei) in the Virunga Volcanoes region of Rwanda, Uganda, and Zaire, has halved from an estimated 400–500 to fewer than 250. The major cause of this decline is loss of habitat through large-scale appropriation of National Park land in Rwanda for agriculture, and through encroachment by local people and their cattle which causes extensive damage to vegetation within the protected area.

This survey has described the foreseeable environmental and economic impacts of enhanced oil-recovery (EOR) on U.S. oil production between 1980 and 2000. It has indicated that EOR production may be expected to rise from the approximately 4% of total U.S. oil production in 1980, to the projected approximations of 10.5% in 1985, 18.5% in 1990, 23% in 1995, and perhaps 30% in 2000. These percentages are substantial, particularly as this form of oil production has been, up until recently, quite limited. Many of the processes are still in the laboratory stage of development—particularly chemical and microbiological processes. With continued laboratory experimentation and field research, it is possible that the percentages could be even greater than the above suggestions as we reach into the 21st Century.

The potential for EOR is very considerable and probably great, as it could involve some two-thirds of all the oil already identified in the United States and assumed to be unrecoverable by primary or secondary means. The U.S. Department of Energy (DOE) has given important incentives to the EOR industry to make such increased production worth while through raising prices to compensate for the cost of equipment, and deducting expenditure on such equipment from a new ‘Windfall Profit Tax’.

Along with EOR's economic potential, there are two major ecological dangers: air pollution through thermal processes, and ground-water pollution through chemical processes. It is essential to the well-being of the United States that clean air standards be adhered to, and that the equipment necessary to purify the air (particularly in California) be available and operate to reduce emissions.

A great deal more research needs to be undertaken towards developing safeguards to ensure that drinkingwater is not contaminated by dangerous chemicals which may be used in ‘chemical flooding’ of depleted oil-wells. Many of these chemicals have merely ‘come out of the laboratory’ and are sold by chemical companies without sufficient field-testing. How far these chemicals could travel underground must still be determined. It is also important to ensure that carbon dioxide, fed into a geological formation, can be recaptured and re-injected without escaping into the atmosphere, where there is the potential danger of a global ‘greenhouse effect’ upon the world's temperature. Finally, it is important to safeguard the Earth against microbes which could be injected into its geological strata without sufficient knowledge of their impact on the ecology of the Earth. Thus, much environmental research will be called for with these new methods of producing oil for Man's use.

This study has reviewed the four major methods of EOR that are currently being utilized or proposed— thermal processes, miscible and semi-miscible processes, chemical processes, and microbiological processes, and found that they could all have ongoing possibilities.

Given appropriate environmental safeguards, EOR should become a major force in the production of energy for the United States over the next 20 years, and it seems reasonable to expect that much the same could apply to other parts of the world. However, it is important that safeguarding the environment should guide the DOE in terms of its incentive programmes for specific processes.

For over a century the foundation of biological conservation has been the development of open space networks either through outright public land acquisition or appropriate management of private lands. Because both approaches come with significant trade-offs, it is critical to understand which species are found across various land ownership types so that policy tools and management actions can efficiently be targeted to do the most good. In this paper, presence-only biological data were used to create species distribution maps for 18 imperilled forest bird species that breed within the deciduous forests of New Jersey (USA). These maps, combined with publicly available, spatially explicit information on land ownership, document who owns the habitat relied on by each of these 18 species. There were significant variations in both species- and guild-specific reliance on public versus private lands, with the latter preferentially supporting nearly twice as many species as the former. Subcategories of land ownership provided support for the role of both state-owned forests and privately-owned agricultural lands in forest bird conservation; however, each landownership type supports a distinct set of species. While explicitly recognizing the need to employ diverse conservation strategies, the approach provides a solid framework for structuring forest conservation planning and policy at regional scales.

As part of a programme of landscape-scale habitat surveillance in the United Kingdom (UK), the effect of grassland sampling intensity on the outcome of numerical classification was assessed. Sample quadrats from two regions of the UK were available for post priori analysis; a random sample from Great Britain (GB), with grasslands sampled in proportion to area, and an independent stratified random sample from Northern Ireland (NI), with similar numbers of quadrats from agricultural and semi-natural grassland habitat strata. Classification of a combined area-proportional (balanced) random sample from GB and NI showed the species composition of UK grasslands to be determined largely by climate, landscape structure and land-use intensity. The classification was influenced primarily by the greater number of eutrophic agricultural grassland quadrats and semi-natural grassland quadrats of the larger GB study area. The semi-natural grasslands of NI, represented by a small number of quadrats, had little influence. Classification of a stratified NI sample combined with an area-proportional GB sample was influenced most by the NI semi-natural grassland quadrats. The structure of the classifications depended on sampling intensity. Vegetation classification should be derived from a balanced sample so that it is representative and its application does not lead to decisions being directed at classes of vegetation (or estimates derived from them) that are weighted by sampling intensity. Area-proportional sample design linked explicitly to landscape structure satisfies the requirement for a balanced classification. The issue of data-balance is relevant in conservation management and environmental assessment, where stratification is a commonly accepted procedure to reduce sampling effort, or is carried out to sample rare or ecologically interesting vegetation. It applies to landscape-scale vegetation classifications used for environmental assessments and to classifications that compare plant communities between regions (as in phytosociological studies). The issue is also important when combining environmental databases from international sources for classification purposes.

When compared to tropical forest zones in west and central Africa, off-take of wild meat from savannah and grassland biomes by local rural communities has not been well assessed. This case study of wild meat collection activities within a rural community in the Mount Frere region of the Eastern Cape (South Africa) uses last-catch records derived from 50 wild meat gatherers to calculate average off-take of taxa, species and fresh mass of wild meat per collection event. When per-event off take is overlaid onto household hunting frequency data, annual off-take would be 268.6 kg km−2 yr−1 or 3 kg person−1 yr−1 presuming constant off-take over an annual period. Monetary value of off-take would be South African R 307 (US$ 39) per household annually. For some species, off-take weight per km2 shows similar values to data from tropical forest zones, but high human population densities tend to dilute off-takes to less nutritionally significant amounts at the per person scale. However, unlike many tropical zones, none of the species harvested can be considered high-priority conservation species. Even densely populated and heavily harvested communal lands appear to offer high wild meat off-takes from low conservation priority species.

Despite sound logic supporting decentralized resource management, the results of community-based natural resource management (CBNRM) efforts have been mixed. Many conditions are thought to contribute to the sustainable use of common pool resources, but as practitioners evaluate the likelihood of CBNRM success, it is necessary to understand which particular conditions have the greatest impact and how these differ across contexts. This paper describes the harvest of the matsutake mushroom and its decline in two rural communities in Bhutan that possess many of the conditions thought to facilitate resource management. Data from surveys, informal interviews and focus group meetings suggest the decline in the matsutake harvest can be attributed to the absence of a small number of enabling characteristics and an additional factor that is often overlooked in the CBNRM literature. Factors contributing to the decline include environmental dynamics, lack of leadership, and the difficulty of monitoring and enforcing harvesting guidelines. However, communities are reluctant to absorb the costs of developing institutions owing to the lack of perceived scarcity and salience of matsutake and, perhaps most importantly, to a historical dependence on a paternalistic government. This reliance on the government may preclude communities from assuming the responsibilities of matsutake management and enforcing rules to assure a sustainable harvest, a trend seen elsewhere in Bhutan. CBNRM may succeed if governments can simultaneously build capacity in communities while empowering them to take ownership over resource management. Though a relatively small number of factors have impeded CBNRM in this case, many of the obstacles can be overcome and these efforts should be considered a work in progress in Bhutan.

There is much to be learned if we are to optimize the procedures for maintaining ice-free roads in the wintertime. Sociological studies indicate that investigations should not only be of technological measures to maintain bare pavements for ‘summer driving’ in the winter, but also we might well reduce the driver's expectations, educate him or her in the matter of how to drive under hazardous conditions, and generally accept a lower level of mobility in exchange for reduced costs and environmental damage.

Increased availability and efficiency of public means of transit may be forced upon an unwilling public in the years to come by a much-reduced portable energy-source (gasoline), and this change in transportation habit may have further impact on winter maintenance procedures. For many reasons, we can no longer use the methods of the past with a gay disregard for our environment and often limited resources faced by an increased world population.

The paper deals mainly with the use particularly of common salt (NaC1), but also of calcium chloride (CaCl2) and the defroster Verglimit, to reduce hazards on roads in times of freezing temperatures, and concludes that, whereas the former single chemicals pose environmental problems as possible ground-water and surface-water hazards to humans and their corrodible possessions, as well as to vegetation especially near treated highways, the multi-chemical patented Verglimit offers an encouraging new approach—apart from its high cost which, however, can be mitigated to some extent by judiciously limited application.

Most of the features that are commonly attributed to typical tropical rain-forests, such as a preponderance of woody vegetation and species with leaves in the mesophyll size-class, tall slender trees with ‘flying buttress’ and unusually thin bark, multilayering of vegetation with abundance of epiphytes and stranglers, evergreenness, strong tendency to change in species composition in time and space, and high diversity of dominance, are plentifully displayed by the forests of the Silent Valley in southwestern India. A relatively high species-richness, remarkably thin bark of trees, and high total tree-basal area, indicate that the valley embodies a virgin forest and that conditions for growth are very favourable. Because of the terrain, heterogeneity in habitats is well marked.

The proposed construction of a dam and large flooding reservoir threatens to bring about several undesirable alterations in the environment of the Silent Valley rain- and riparian forests, and the disturbances that would follow such construction and flooding would be highly detrimental to the diversity of the forests and to the complexity of their structure. Hence a plea is made for the setting aside forthwith of a proposed major ‘Silent Valley Biosphere Reserve’, which could safeguard a unique part of the world's genetical heritage and one of its most interesting complexes of natural ecosystems.

The success of natural resource management depends on monitoring, assessment and enforcement. In support of these efforts, reference points (RPs) are often viewed as critical values of management-relevant indicators. This paper considers RPs from the standpoint of objective-driven decision making in dynamic resource systems, guided by principles of structured decision making (SDM) and adaptive resource management (AM). During the development of natural resource policy, RPs have been variously treated as either ‘targets’ or ‘triggers’. Under a SDM/AM paradigm, target RPs correspond approximately to value-based objectives, which may in turn be either of fundamental interest to stakeholders or intermediaries to other central objectives. By contrast, trigger RPs correspond to decision rules that are presumed to lead to desirable outcomes (such as the programme targets). Casting RPs as triggers or targets within a SDM framework is helpful towards clarifying why (or whether) a particular metric is appropriate. Further, the benefits of a SDM/AM process include elucidation of underlying untested assumptions that may reveal alternative metrics for use as RPs. Likewise, a structured decision-analytic framework may also reveal that failure to achieve management goals is not because the metrics are wrong, but because the decision-making process in which they are embedded is insufficiently robust to uncertainty, is not efficiently directed at producing a resource objective, or is incapable of adaptation to new knowledge.

Increasing net-zero commitments by individuals, companies and governments have been accompanied by the growth of the voluntary offset market, including Reducing Emissions from Deforestation and Forest Degradation (REDD+). Technologies, notably blockchain, are starting to enter the REDD+ space and may have the potential to address issues such as additionality, permanence, leakage and property and community rights. In this Perspective, we first examine voluntary markets and the role forest carbon offsets have played within them, highlighting the evolution of REDD+ and the issues that have hindered its development. We then examine the potential of blockchain to address each of the issues, using the literature and emerging experience from the use of blockchain in the forestry space. We find that the technology may have the potential to improve verifiability, reduce transaction costs and, to a lesser degree, aid in addressing additionality and permanence concerns. However, greater learning from the emerging use of blockchain in pilot projects is needed to fully assess and maximize its potential.

A comparative study of institutional arrangements for the implementation of environmental policies serves several purposes. First, it provides a better understanding of the governmental systems of the respective countries which are examined. Second, it provides a basis for the potential formulation of more effective environmental protection policies; this can be accomplished through a detailed analysis of the implementation efforts of countries which experience similar environmental problems, but may use different implementation strategies to deal with such problems. Third, it prompts the analyst to consider the effect of varying political cultures on the policy implementation process (Enloe, 1975). Fourth, such study often identifies the need for greater harmonization of environmental laws between different countries (Lutz, 1975). In sum, such study can reveal the key relationships between governmental structures and environmental policies which account for successful policy implementation (Lundqvist, 1974).

Environmental problems of agriculture constitute some of the most complex and significant problems of modern times. They are found in all countries, but are most prominent—and tend to be most serious—in Third World countries located in ecologically vulnerable areas. Their roots commonly lie in the culture of the population, the farmers' behaviour, or the economy of the area.

In order to assess patterns of agricultural development in general, or to assess the implications of development projects, we must include the environmental, behavioural, and policy, dimensions of the agricultural production system into a single framework, so that we can understand both the problems as narrowly defined and the measures which must be taken in order to solve them.

One way of doing this is through a comprehensive, out qualitative, overview of the system. This provides a general framework for any analysis, and it can be so simplified that a particular problem can be treated in a meaningful and adequate fashion.

The Picos de Europa are representative of the diverse cultural landscapes of Spain that are currently threatened by changes in traditional management practices. They contain the first national park to be declared in Europe, and, although this has recently been extended, there is no policy to support the traditional agricultural practices that maintain the landscape. The Environmentally Sensitive Area (ESA) scheme in Britain is described in order to provide an appropriate policy background within which the ecological characteristics of the region could be maintained. The general background to the environment of the region is then described, with its unique interactions amongst limestone rock, climate, species and anthropogenic influences that have produced a complex cultural landscape. A statistical classification of the region was constructed which, in conjunction with a field survey, enabled the ecological resources to be assessed, and also identified the principal threats to the character of the region. It is suggested that ESA-style legislation could provide a valuable policy instrument to encourage maintenance of the cultural landscape and some appropriate prescriptions are proposed for this purpose.

This article appreciatively reviews environmental education practice on islands through the lens of four key strands of environmental education discourse: biodiversity, conservation and science-framed education; place-based, indigenized and bioregional education; climate change and disaster risk reduction education; and education for sustainable development. Arising from these strands and their interface, six questions are asked of the examples of island practice reviewed. A final section asks what is distinctive about environmental education on islands and comes up with five principal findings. First, it is observed that environmental education initiatives on islands are markedly eclectic in their rich blending of practice from within the different strands. Second, it is noted that environmental education practice on different islands, especially in the Pacific, is marked by a return to indigenous, community-based learning. Third, the emergence of a distinctive pedagogy is remarked upon, especially the greater weighting given to relational, socio-affective and action-orientated learning. Fourth, the paucity of inter-island cosmopolitan dialogue is noted and questions are asked about how to ensure island learners steeped in learning about place can be brought to connect with the global environmental problematic. Fifth, the frequency of cross-curricular, interdisciplinary, even trans-disciplinary framing of environmental education initiatives is identified as bringing distinctiveness to island practice.

Differences are emerging in decentralization of forest and community management in Zimbabwe, Mozambique and South Africa. This paper draws on case studies in each country to examine five aspects of their decentralization experience, namely forest tenure, new organizational structures, accountability and livelihood outcomes. Tenure arrangements developed as a result of decentralization are important for communities, as these determine the nature of access sanctioned by the state and security of the arrangements. The transfer of power to new organizations is proving to be a challenge. Experiences across the three case studies show that new committees were formed for these forestry initiatives by outside agencies and attempts were made to make them relevant to the way local communities managed forests. One of the main tenets of decentralization revolves around accountability of community representatives to their constituents rather than to the state. Although moves have been made to promote the accountability of community representatives, these have produced mixed results in Zimbabwe, Mozambique and South Africa. Only after changes in the approach taken by the state in Zimbabwe did community representatives become more accountable. In Mozambique, because of the special arrangements around the specific case, greater authority was given to community representatives, whereas, in South Africa, the state retained authority over representatives. Decentralization may bring benefits and improve communities' livelihoods from forestry activities, however much more still needs to be done by states in order for forests to take communities out of poverty.

The biological status of an isolated, man-made pond established in 1957 is described principally after its first 20 years of existence. The pond is located in the dry sagebrush region of south-central Washington (USA), and is colonized by Bulrushes, Cattails, and numerous Algae. Migratory waterfowl were the first vertebrate users of the pond; and with the establishment of shoreline plant communities and submerged macrophytes, the pond now provides nesting habitat for several duck species, American Coots, and Pied-billed Grebes. Use of the pond by large mammals is limited to visits by Mule Deer, Coyotes, and Raccoons. There are no Muskrats or Beavers in the pond. Turtles and Garter Snakes are not found in or around the pond but are present in the near-by Columbia and Yakima Rivers. The absence of these vertebrate animals is attributed to the isolation of the pond and the absence of connecting surface waterways between the pond and the regional watercourses. The only fish in the pond are Goldfish—presumably of artificial introduction.

Some of the more sedentary pond organisms—aquatic arthropods, crustaceans, and snails—may have reached the pond in raw Columbia River water, or been transported as eggs externally attached to waterfowl, or possibly been voided into the pond along with avian faecal material.

The pond contains low levels of industrially-derived radionuclides—especially caesium-137. Radiocaesium is mostly confined to bottom sediments, but is readily assimilated by biota and so appears in all trophic levels. Some of the societal concerns and research potentials associated with the pond are discussed with special references to food-chain and biotic transport mechanisms.

There is burgeoning interest in predicting road development because of the wide ranging important socioeconomic and environmental issues that roads present, including the close links between road development, deforestation and biodiversity loss. This is especially the case in developing nations, which are high in natural resources, where road development is rapid and often not centrally managed. Characterization of large scale spatio-temporal patterns in road network development has been greatly overlooked to date. This paper examines the spatio-temporal dynamics of road density across the Brazilian Amazon and assesses the relative contributions of local versus neighbourhood effects for temporal changes in road density at regional scales. To achieve this, a combination of statistical analyses and model-data fusion techniques inspired by studies of spatio-temporal dynamics of populations in ecology and epidemiology were used. The emergent development may be approximated by local growth that is logistic through time and directional dispersal. The current rates and dominant direction of development may be inferred, by assuming that roads develop at a rate of 55 km per year. Large areas of the Amazon will be subject to extensive anthropogenic change should the observed patterns of road development continue.

We investigated how the socio–political and ecological environment are associated with the conservation management strategies for two rare, endemic and almost identical Australian white-tailed black-cockatoos: Baudin's (Calyptorhynchus baudinii) and Carnaby's black-cockatoo (C. latirostris). Substantially less investment and action has occurred for Baudin's black-cockatoo. Interviews with key informants revealed that this disparity has probably arisen because Baudin's black-cockatoo has long been considered a pest to the apple industry, lives primarily in tall forests and has had little research undertaken on its biology and threats. By contrast, Carnaby's black-cockatoo has been the subject of one of the longest running research projects in Australia, is highly visible within the urban environment and does not appear to affect the livelihoods of any strong stakeholder group. We suggest the social context within which recovery efforts occur could be an important determinant in species persistence. We argue that social research is fundamental to a better understanding of the nature of efforts to conserve particular species, the factors associated with these efforts and their likelihood of success.

A conventional conservation strategy is establishing protected areas to help combat anthropogenic and climate change impacts on tropical ecosystems, but the effectiveness of these measures is often hampered in upland areas by resource conflicts among armed groups, citizens and government institutions. Improved governance and community participation are key to effectively conserving these areas, yet little is known regarding citizen perceptions in such places. Here, a representative protected area in Colombia is used in order to analyse rural and urban citizen perceptions regarding conservation, conflicts with guerrilla groups and nature’s contributions to people (NCPs) around Chingaza National Natural Park. We used on-site, semi-structured in-person surveys, geospatial data and statistics to understand these perceptions and the roles of armed conflict and deforestation. Perceptions on ecosystem degradation were correlated with deforestation and past guerrilla attacks. Age and place of residence were influential pro-conservation factors, while younger respondents were most willing to invest time in conservation activities. Air purification and water supply and quality were the most identified NCPs and citizens differentiated conservation-related recreation activities from natural resource extraction. We suggest that the legacy of past armed conflict still affects conservation strategies and communities living near tropical highland protected areas.

Technological change in the UK herring industry took place rapidly after 1965, due in part to the active encouragement encouragement given to fishermen to switch from driftnetting to pelagic trawling and purse-seining. The adoption and diffusion of these modern methods of capture stimulated a major expansion of output, but this very success was undermined by the depletion of the fish-stocks on which the industry depended. In the case of the West of Scotland herring fisheries, which were especially important to UK fishermen, the decline in fish-stock biomass caused vessel catch-rates to fall after 1973. The failure of international fisheries management, which acted as a permissive factor in the intensification of fishing effort, also had important economic implications as it resulted in the dissipation of resource-rent. The Authors calculate that the maximum sustainable ‘rent’ which could have been generated from the West of Scotland herring fishery was approximately £14 millions per annum at 1976-equivalent prices.

The resource-rent effectively financed the overcapitalization of the fleet and the decline which followed, and it is the speed with which this occurred that most distinguishes the herring fishery from others where technological change has taken place. The article concludes by arguing that, although the UK public authorities (notably the Herring Industry Board) might reasonably be criticized for pursuing a development strategy which resulted in economic and biological over-fishing, the international regime of fisheries management which prevailed at the time gave them little choice but to adopt a pro-active approach to technical innovation.