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Pilot Analysis of Global Ecosystems (PAGE): Coastal Ecosystems analyzes quantitative and qualitative information and develops selected indicators of the condition of the world's coastal ecosystems and marine fisheries. Specifically the study looks at measures that show the degree of human modification of coastal zone and what we know concerning five important goods and services provided by coastal ecosystems: filtering water, food, biodiversity, shoreline stabilization, and tourism. Results from the PAGE analysis show that human activities have extensively altered coastal ecosystems worldwide. Nearly 30 percent of the land area in the world's coastal ecosystems had already been extensively altered or destroyed by growing demand for housing, industry, and recreation. Globally, the number of people living within 100 km of the coast increased from roughly 2 billion in 1990 to 2.2 billion in 1995—four out of every ten people in the world. As coastal and inland populations continue to grow, their impacts—in terms of pollutant loads and the development and conversion of coastal habitats—can be expected to grow as well. Nutrient pollution has increased dramatically this century due to greater use of fertilizers, growth in quantities of domestic and industrial sewage, and increased aquaculture, which releases considerable amounts of waste directly into the water. Increasing fishing pressure have left many major fish stocks depleted or in decline. Global climate change may compound other pressures on coastal ecosystems through the additional effects of warmer ocean temperatures, altered ocean circulation patterns, changing storm frequency, and rising sea levels.