Indirect sources were used to characterize the nature and magnitude of threats to the native plants and forest ecosystems caused by the cultivation and control of coca, the precursor to cocaine, in the Huallaga valley of Peru, whence the majority of the world's cocaine originates. Deforestation is concentrated between 500 and 2000 m in the tropical premontane forest belt. Recent listing of Peru's seed plants permitted a quantification of plant species known from the department of San Martin between 500–2000 m and thus at risk due to forest degradation. This flora consists of 169 plant families, almost 900 genera, and about 2600 species. Fifteen percent of the species are restricted in distribution to Peru, while 6% are known only from San Martin. An additional 778 species, including 46 narrow endemics, are known from vegetation types found below 500 m. More than 223 000 ha of land were found to be in ‘hill agriculture’, consisting predominantly of coca fields and this suggests that the total impact of coca/cocaine deforestation is greatly under-estimated by using simply the area of coca under cultivation. Degraded tropical pre-montane forest may amount to as much as 1 000 000 ha in all of Peru.

Many natural and human-induced events create disturbances in seagrasses throughout the world, but quantifying losses of habitat is only beginning. Over the last decade, 90000 ha of seagrass loss have been documented although the actual area lost is certainly greater. Seagrasses, an assemblage of marine flowering plant species, are valuable structural and functional components of coastal ecosystems and are currently experiencing worldwide decline. This group of plants is known to support a complex trophic food web and a detritus-based food chain, as well as to provide sediment and nutrient filtration, sediment stabilization, and breeding and nursery areas for finfish and shellfish.

We define disturbance, natural or human-induced, as any event that measurably alters resources available to seagrasses so that a plant response is induced that results in degradation or loss. Applying this definition, we find a common thread in many seemingly unrelated seagrass investigations. We review reports of seagrass loss from both published and ‘grey’ literature and evaluate the types of disturbances that have caused seagrass decline and disappearance. Almost certainly more seagrass has been lost globally than has been documented or even observed, but the lack of comprehensive monitoring and seagrass. mapping makes an assessment of true loss of this resource impossible to determine.

Natural disturbances that are most commonly responsible for seagrass loss include hurricanes, earthquakes, disease, and grazing by herbivores. Human activities most affecting seagrasses are those which alter water quality or clarity: nutrient and sediment loading from runoff and sewage disposal, dredging and filling, pollution, upland development, and certain fishing practices. Seagrasses depend on an adequate degree of water clarity to sustain productivity in their submerged environment. Although natural events have been responsible for both large-scale and local losses of seagrass habitat, our evaluation suggests that human population expansion is now the most serious cause of seagrass habitat loss, and specifically that increasing anthropogenic inputs to the coastal oceans are primarily responsible for the world-wide decline in seagrasses.

Trade in tropical timber, while a minor cause of deforestation in the tropics, can be a substantial factor in promoting forest degradation and deforestation. International organizations and conferences increasingly recognize that adverse environmental effects of international trade can be reduced through regulations and economic incentives. Three international agreements, the GATT, the CITES, and the ITTA, now affect the tropical timber trade and are here reviewed. Adopted at different times, they illustrate different philosophies, pursue different objectives, and develop contradictory trade policy perspectives. Legal conflicts among these agreements reduce their effectiveness, and mitigate a global objective of making international trade in tropical timber more responsive to environmental issues. Harmonization among the GATT, the CITES, and the ITTA, and collaboration among organizations in charge of managing these agreements, should be reinforced in order to establish a coherent and uniform policy for tropical timber trade.

We review several studies and provide new data previously unpublished to show that there has been a substantial decline in pollution of German riverine waters since the beginning of German political reunification in 1989. This reduction is notable in the Elbe, which originates in eastern Germany and the Czech Republic. Pollutants such as many of the chlorinated hydrocarbons have fallen substantially in concentration, while others such as arsenic have declined only slightly. Total nitrogen has declined by only a small amount, but ammonium has fallen substantially, while nitrates have increased. Nitrification is no longer a significant drain on oxygen in the tidal stretch of the Elbe, but decomposition of algae from the middle Elbe is now a greater problem in the lower Elbe. The river-bed sediments of the middle Elbe have a higher species diversity. Fisheries are improving, and concentrations of pollutants in fish such as eel and bream have declined significantly. The river Werra has also improved in quality due to reduction in salt loadings from earlier potash mining.

Wetlands in India supply crucial human and animal needs such as drinking water, protein production, fodder, water purification, wildlife habitat, and flood storage. Increased appreciation of uses and threats is essential to protect wetlands where justified. Three quarters of India's population is rural, it places great demands on India's wetlands and losses continue to occur. This paper is based on extensive discussions with natural resource managers, government employees, farmers, academicians, and resource users at dozens of sites in India, as well as an extensive literature search. Twelve important kinds of wetland loss are identified and mechanisms believed to be causing them discussed: (1) agricultural conversion, (2) direct deforestation, (3) hydrologie alteration, (4) inundation, (5) defoliation, (6) altered upper watersheds, (7) accumulative water demands, (8) water quality degradation, (9) wetland consolidation, (10) global climate change, (11) ground-water depletion, (12) exotic species and biodiversity. Wetland understanding, management, and Public awareness in India must continue growing if wetland resources are to remain functional.

Pollution from many sources, over-fishing and the rapid development of Hong Kong have had powerful, adverse, impacts upon local marine life reducing it to but a shadow of what it once was. This paper describes Hong Kong's newly enacted Marine Parks Ordinance Chapter 37 1995, discusses the existing situation with regard to the designation of marine parks and reserves, and describes the special features of each one. It argues that a territory-wide strategy will have to be implemented if representative intertidal and coastal water communities are to survive. Coastal zone planning and management need to be among the Hong Kong Government's highest priorities because there are indications that the marine parks and reserves will not be successful. The threats to them are too great. Conservation legislation and coastal planning exercises should also be integrated with those of China as soon as possible, especially for areas of coastline surrounding Hong Kong. This is because development within southern China is proceeding at such a pace that Hong Kong's protected areas are now being threatened by external factors as well as internal ones.

Integrated conservation and development projects (ICDPs) involve the establishment of parks and reserves with protective or buffer zones around them. Socio-buffering provides local residents with alternatives to traditional land-use activities, but the actual implementation of socio-buffering programmes is difficult.

Socio-economic requirements and constraints to socio-buffering were assessed for the Mantadia National Park in eastern Madagascar based on five criteria. Previously unused lands for compensating people for loss of access to areas within the park were found to be insufficient. While there existed institutions and programmes for developing substitute land-use activities, successful adoption of these activities was crucially dependent on their economic viability. Socio-buffering activities need to not only provide goods that are substitutes for goods that are traditionally consumed, but they also need to be at least as profitable as traditional economic efforts. Also, if land and labour are not a constraint to agricultural expansion, socio-buffering activities can themselves result in increased deforestation. Finally, the long-term effectiveness of socio-buffering was likely to be dependent on the satisfaction of a number of stake-holder interests, and on explicit linkages developed between socio-buffering activities and conservation.

Many high altitude regions of the world are still occupied by traditional communities of people, whose livelihood is closely related to a narrow base of locally available natural resources. A survey was conducted in 1991–94 of two villages inhabited by Bhotiya tribal people in Dharchula block of Uttar Pradesh, India. Medicinal herbs (14 abundant species, with Partitella ramitchadalis accounting for >50% by weight) constitute 12–13% of total income to the villages. The harvest is conducted by children during August to October, around summer settlements (up to 4100 m altitude) to which the villagers annually migrate. Fifteen cooperatives with a 1992 membership of 7009 herb collectors and salespeople exist in the Dharchula block, and marketing is through two specialist government agencies. Conservation measures, including protected areas and banning of direct trade with purchasing companies, have not generally been successful; pressure on the plant populations has increased and there is evidence for decline in the resource. Cultivation appears to represent a viable option for the resource, and thus for the income of the traditional peoples who still depend on it.

The purpose of this paper is to explore the phenomenon of ‘environmental refugees’. The emergence of refugees within the framework of international law and policy is examined briefly so as to provide insight into the juridical difficulties environmental refugees can expect to confront. The literature on environmental refugees is steadily growing and the very definition of who qualifies as an environmental refugee has undergone great changes. The evolving nature of the definition and its increasing complexity is reviewed; the result being that environmental refugees can now be placed into several well-defined groupings, each with its own idiosyncratic characteristics. These increasingly distinctive groups of refugees can have as debilitating consequences as other types for receiving societies. The nature of this threat must be looked at fully in order to emphasize the urgent need to arrive at appropriate solutions. Finding solutions to a new crisis is not a simple task as many people fiercely oppose recognition of environmental refugees. Yet, failure to act may prove detrimental to human well-being as the emerging evidence points to a state of affairs that may haunt humankind in the twenty-first century.