Natural disaster reduction and environmental management: a geomorphologist’s view

Abstract

Natural hazards, threatening many parts of the world, are often ignored in the context of regional planning and environmental management, although this is necessary for avoiding, or at least substantially reducing the recurrence interval and magnitude of the related «natural» disasters. This is particularly the case for «creeping» disasters, related to environmental degradation caused by slow and in many cases almost imperceptible processes, including desertification, salinization, certain forms of soil erosion, pollution, etc. The more spectacular instantaneous disasters, resulting from high-intensity and low-frequency natural events of endogenous or exogenous origin, are nowadays reported about by the media world-wide. They are, however, soon out of focus again and adequate measures to prevent similar disasters in the future do not always remain a high priority of the responsible authorities. Disaster reduction through environmental management is a complex issue that requires interdisciplinary applied research related to the natural environment as well as to the socio-economic situation of the endangered societies. In fact, sustainability is at stake. For the implementation of adequate protection measures, ranging from «hard» engineering structures to «soft» management improvements, optimal cooperation between the various sectors of the communities concerned is essential. This multisectoral approach should lead up to a master-plan for long term regional management and a disaster scenario specifying tasks and responsibilities of organizations and individuals in case of an emergency situation. Apart from natural disasters, technical-industrial disasters and also the, often neglected, ecological disasters should be considered. Humanitarian disasters are, unfortunately, largely outside the field of science. The UNIDNDR (International Decade for Natural Disaster Reduction) program of the 19nineties concentrated on natural disasters only. Its follow-up, the UN-ISDR (International Strategy for Disaster Reduction), has a broader scope because technological / industrial disasters are also included. Examples are given of volcanic disasters in Indonesia, including gas emanations on the Dieng plateau and pyroclastic flows on the densely populated SW slopes of the Merapi volcano in Central Java, Further, the effects of the ill-famed eruption of the Nevado de Ruiz volcano, Colombia in 1985 are discussed in relation to shortcomings in disaster mitigation systems. Drought and desertification studies executed in northern Chad and in Botswana are discussed thereafter as an introduction to the problems of assessing and achieving global sustainability problems.