PROFILE: Indigenous Institutions and Environmental Assessment: The Case of Ghana

/ The search for sustainable development provides the impetus forexamining the role of indigenous institutions and their ecological knowledgein environmental assessment and local sustainability. This paper attempts totrace the evolution of environmental assessment in Ghana. Focusing on theAshanti Region, the paper further discusses the nature and operations ofindigenous institutions, their ecological knowledge, beliefs, practices, andsocial norms that are relevant to environmental assessment process in thecountry. Some of the challenges that emerge from the discussions arehighlighted. There is a need to establish environmental assessment andcooperative management boards that would include representatives ofindigenous institutions. In addition, the introduction of technicaldictionaries and training manuals based on indigenous ecological knowledgeand their humane environmental practices will further improve theenvironmental assessment process in Ghana.KEY WORDS: Environmental assessment; Indigenous institutions; Indigenousecological knowledge; Sustainable development; Environmental assessmentboards     

PROFILE: Hungry Water: Effects of Dams and Gravel Mining on River Channels

/ Rivers transport sediment from eroding uplands to depositional areas near sea level. If the continuity of sediment transport is interrupted by dams or removal of sediment from the channel by gravel mining, the flow may become sediment-starved (hungry water) and prone to erode the channel bed and banks, producing channel incision (downcutting), coarsening of bed material, and loss of spawning gravels for salmon and trout (as smaller gravels are transported without replacement from upstream). Gravel is artificially added to the River Rhine to prevent further incision and to many other rivers in attempts to restore spawning habitat. It is possible to pass incoming sediment through some small reservoirs, thereby maintaining the continuity of sediment transport through the system. Damming and mining have reduced sediment delivery from rivers to many coastal areas, leading to accelerated beach erosion. Sand and gravel are mined for construction aggregate from river channel and floodplains. In-channel mining commonly causes incision, which may propagate up- and downstream of the mine, undermining bridges, inducing channel instability, and lowering alluvial water tables. Floodplain gravel pits have the potential to become wildlife habitat upon reclamation, but may be captured by the active channel and thereby become instream pits. Management of sand and gravel in rivers must be done on a regional basis, restoring the continuity of sediment transport where possible and encouraging alternatives to river-derived aggregate sources.KEY WORDS: Dams; Aquatic habitat; Sediment transport; Erosion; Sedimentation; Gravel mining     

Eco-neighbourhoods: A review of projects

The recent literature on sustainable urban form has stressed the need to move away from a system of land-use segregation and towards one which intersperses land uses and facilitates localisation. The strategy of dispersed concentration gives shape to this mixed-use principle, and has been equated with the need to plan more self-sufficient neighbourhoods. There are several problematic issues raised by such a strategy, particularly in relation to the propensity of local people to use local facilities when the friction of distance is low. The image of sustainable neighbourhoods purveyed by advocates is at odds with the reality of suburban development. A review of current eco-neighbourhood projects around the world points to the varying degrees to which they have successfully overcome the implementational and behavioural difficulties. Market-led projects — particularly in semi-rural areas — have achieved rather limited success across the range of sustainability criteria. Some large-scale municipally led plans have faired better. Projects led by community non-profit trusts have been able to be most radical and demonstrate the practicability of eco-neighbourhoods in specific situations. Overall, however, the paucity of successful projects highlights the need for a more proactive central and local government stance.     

Conservation at landscape level: A strategy for survival: The role of research

Summary The objectives, appropriate strategies, the state of conservation in South Africa, and the contributed research which is needed, are evaluated. It is suggested that the ultimate objectives of conservation are to maintain the ecosystem to support people and to achieve economic advantages. These can only be obtained by providing for the greatest possible diversity of life on Earth. An appropriate conservation strategy can be based on a balanced combination of five types of conservation opportunities. These opportunities are: (i) formal conservation in reserves, (ii) promotion of land use change for conservation, (iii) law enforcement, (iv) national resource utilisation planning, and (v) the development of a national land ethic. Adjustment of the opportunity combination to address changing threast must be an ongoing exercise. Conservation strategies need to be based on sound conceptual models of ecosystem structure and function, as well as human needs and aspirations. The main goals of the conservation ecologist are the development, testing and validation of conceptual models of ecosystems.Mr Zak Le Roux is employed in the Scientific Services Section of the Ecosystem Conservation Department of the Natal Parks Board. He possesses a BSc in Forestry and Nature Conservation from the University of Stellenbosch, and is currently undertaking research in Plant Ecology at the University of Natal. A tenth generation South African, his work focuses on vegetation dynamics of semi-arid savanna landscapes and general conservation in Zululand. In particular, this involves the integration of wildlife with agriculture, and the development of more appropriate land uses in the areas surrounding the parks.     

PROFILE: Tourism Contribution to Agro-Ecosystems Conservation: The Case of Lesbos Island, Greece

The objective of this study was to investigate the impact of tourism activities on olive tree cultivation and the human population of the island of Lesbos. The presence or absence of tourism is related with the maintenance or abandonment of olive tree cultivation and population changes for each community. A spatial segregation of the island is evident, related to tourist development, olive tree cultivation, and population change. The results of the study demonstrate that in communities where tourism plays an important role olive tree cultivation is preserved and the population is stable. The preservation of the agro-ecosystem is assured while the olive groves remain productive. Simultaneously, the landscape, which provides specific attractions for tourism, is not altered.