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ECOSYSTEM SERVICES
1. Ecosystem services are ecologically mediated functional processes essential to sustaining healthy human societies. They can be direct or indirect. Direct ecosystem services are: pollination, wood, erosion prevention, etc. Climate moderation, nutrient cycles, detoxifying natural substances could be considered indirect ones. Water provision and filtration, production of biomass in forestry, agriculture, and fisheries, and removal of greenhouse gases from the atmosphere are examples of ecosystem services essential to public health and economics.
2. Nutrient cycling is a process fundamental to agricultural and forest production. However, like most ecosystem processes, nutrient cycling is not an ecosystem characteristic which can be “dialed” to the most desirable level. Maximizing production in degraded systems is an overly simplistic solution to the complex problems of hunger and economic security.
3. For instance, intensive fertilizer use in the midwestern United States has resulted in degraded fisheries in the Gulf of Mexico. Regrettably, a “green revolution” of intensive chemical fertilization has been recommended for agriculture in developed and developing countries. These short-sighted strategies risk alteration of ecosystem processes that may be difficult to restore, especially when applied at broad scales without adequate assessment of impacts.
4. Ecosystem processes may take many years to recover from significant disturbance. For instance, large-scale forest clearance in the northeastern United States during the 18th and 19th centuries has altered soil texture, dominant vegetation, and nutrient cycling in ways that impact forest productivity in the present day. An appreciation of the importance of ecosystem function in maintenance of productivity, whether in agriculture or forestry, is needed in conjunction with plans for restoration of essential processes. Improved knowledge of ecosystem function will help to achieve long-term sustainability and stability in the poorest parts of the world.
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