區域協作與環境保護 Regional Cooperation with Reference to Environmental Protection,何建宗教授 香港公開大學 Prof. K. C. Ho The Open University of University,Global Environmental Issues with Local, Regional and Worldwide Concern:,Loss of land resources and soil erosion Water shortage and pollution Coastal and marine resources at risk Atmospheric pollution Conservation and biodiversity Deterioration of the quality of living environment Ozone Layer depletion Global warming and climate changes Disasters,Loss of land resources: In 2005, over 70 per cent of the Earths land surface was severely damaged by the construction of roads, mining, urbanization and unplanned economic developments. Latin America and the Caribbean region are likely to be the hardest hit with 80 per cent of the land affected, closely followed by Asia and the Pacific region. Moreover, 75 per cent of valuable habitats are disturbed by human activities including agriculture and urban development, resulting in the loss of biodiversity and other environmental damages.,Soil Erosion: Over 10 per cent, between 25 - 30 million ha, of the worlds irrigated lands are classed as severely derelict. Soil erosion is a key factor in land degradation. Around15 per cent of the Earths land cover or an area bigger than the United States and Mexico combined, is now classed as degraded as a result of human activities. Land degradation mainly results from and with water erosion and spread of agricultural chemicals.,Water shortage and pollution : 60 per cent of the worlds largest 227 rivers have been strongly or moderately fragmented by dams and other engineering works. Half of the worlds rivers are seriously depleted and polluted. In some countries, groundwater levels are falling as a result of over-abstraction. Some 80 countries, amounting to 40 per cent of the worlds population, were suffering serious water shortages by the mid-1990s. There are about 4 billion cases of diarrhea and 2.2 million deaths a year, equivalent to 20 jumbo jets crashing everyday.,Coastal and marine resources at risk: Discharges of untreated sewage is the biggest risk to coastal and oceanic pollution. About one-third of the worlds fish stocks are now ranked as depleted, overexploited or recovering after threats, as a result of over-fishing, harmful algal blooms (commonly known as red tides) and pollution. Other threats to the oceans include climate change, oil spills, discharges of heavy metals, persistent organic pollutants (POPs) and litter.,Atmospheric pollution: Acid precipitation, resulted from emissions of sulfur dioxides, nitrogenous oxides, carbon monoxide and carbon dioxide from burning of fuels, Dirty air affects the health of human beings as well as causing severe ecological damages. Many people die of respiratory diseases and lung cancer due to the pollution of ambient and indoor environments. Thousands of lakes in the world had reductions in fish populations due to acidification from the 1950s to the 1980s. Sources of air pollutants emission include power generation plants, industries and vehicles.,Conservation and biodiversity loss: Forests, which cover around one-third of the Earths land surface (3 866 million ha), have declined by 2.4 per cent since 1990. Production of roundwood for fuel is the main cause of forest loss in developing countries, although commercial logging for the consumption in developed countries is often very destructive Mangrove forests, natural sea defences, nursery grounds for fish and prime nesting and resting sites for migratory birds, are threatened The introduction of alien species from one part of the world to another has emerged as a significant threat in recent years alongside climate change. Alien species often have no natural predators in their new homes and can out-compete native species for breeding and feeding sites.,Deterioration of the quality of living environment: Population increase Increased urbanization Housing Transport Noise Landscape and amenity Reclamation Natural and anthropological heritages,Ozone Layer depletion:,The protection of the ozone layer has become one of the major challenges over the past 20 years. In September 2000, the Antarctic ozone hole covered more than 28 million km3.,Global warming and climate changes : Greenhouse gas (CO2) emissions are unevenly distributed between countries and regions. Organization for Economic Cooperation and Development (OECD) countries contributed more than half of emissions in 1998, with a per capita emission of about three times the world average. Climate change represents an important additional stress on those ecosystems The United Nations Framework Convention on Climate Change and the Kyoto Protocol are the key policy instruments adopted by the international community to try to address the problem of greenhouse gases emissions.,Sea Level Rise,ESPO effects,Disasters: It is estimated that the number of people affected by disasters climbed from an average of 147 million a year in the 1980s to 211 million a