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 Tropical Forests are of huge value to the biodiversity of the planet and hence to the existence of life on it. They exists as home for people and animals as well as serving to regulate moisture and heat around the planet as part of the global weather systems. The many values and functions of tropical forests may be described in terms of 'goods' and 'services' for the purpose of justifying its value to the sceptic.
Benefits of goods and services are commonly assessed in terms of economic value, the monitary value of these banks of resources if they are expoited into the capitalist market economy. This does not account for natural value of these incredible environments and their role in maintaining the balance of global climate for example. However today, the modern world is increasingly recognising and acceptiong the importance of 'existence', the intrinsic and cultural values of the natural world.
Services
Climate Regulation
- Rainforests are global heat and water pumps. Forests add to local humidity through transpiration, but above a rainforest the air is cooler so it is more likely to rain. Beneath the dense canopy humidity stays high and steady. The forests stay wet and evaporate vast quantities into the air above, forming clouds. Some falls again in the tropics but often clouds are carried great distances to fall as rain in the mid latitudes, often as far away as Europe and Australia.
- Reducing forest cover reduces evaporation, more solar energy warms the earth's surface increasing air temperature. The hotter air over desert and grassland habitats, often replacing rainforests following logging or clearing, discourages cloud formation and deserts remain dry.
- For more information visit: www.tropenbos.nl
Greenhouse Effect
- Tropical forests have the best potential for greenhouse gas mitigation with the capacity to store carbon in their tissues as they grow. Reforestation of 3.9 million m2 (10 million km2) could sequester 100-150 billion metric tons of carbon dioxide over the next 50-100 years.
- For more information visit: www.unep-wcmc.org
Watershed Protection
- Forests help prevent drought and flooding by reataining water from tropical downpours and releasing it at a controlled rate. In a well-forested watershed, 95% of annual rainfall is trapped and released steadily, replenishing ground water and keeping streams flowing through dry seasons.
- This constant supply of clean water is vital for sustaining an area's natural ecology. If large areas of watershed are deforested, catastrophic flooding can occur at huge environmental, economic and social costs. The Philippines is often affected by such events.
- One of the most vital local functions fulfilled by forests is control of rainfall run-off to waterways.
- For more information visit: www.tropenbos.nl
Soil Erosion Prevention
- Linked to watershed protection is limiting sediment run-off, since forests anchor the soil with their roots. After heavy rains fall on deforested lands, run-off carries soil into local rivers increasing siltation, raising riverbeds, and leading to increased flooding. The increased sediment load is detrimental to river ecology, reducing light for photosynthesis, and smothering fish eggs.
- On reaching the ocean, the water becomes cloudy causing regional declines in coral reefs.
- For more information visit: www.tropenbos.nl
Goods
Forest Resources: Timber
- Forestry is important both to world economy, contributing 2% world GDP and 4% of GDP in developing countries, and comprising 3% international trade, and also to the local economies of many countries.
- Timber is important at a local level, as a construction material in subsistence communities.
- For more information visit: www.tropenbos.nl
Non-timber forest products (NTFPs - includes fibres, resins, plant and animal products)
- An estimated 80% of the developing world relies on NTFPs. Although many are collected locally, some have been domesticated for large-scale production. In the international marketplace, NTFPs account for over US$1.1 billion in trade.
- The projected economic value* of one hectare of forest in the Peruvian Amazon was US$6,820 per year if intact forest is sustainably harvested for fruits, latex and timber. But only US$1,000 if clear-cut for commercial timber (not sustainable) and US$148 if used as cattle pasture(*from Peters C.M., Gentry A.H., Mendelsohn R.O. (1989) Valuation of an Amazonian Rainforest. Nature Vol.339, pp 655-656).
- For more information visit: www.tropenbos.nl
Food source
- An estimated 75,000 edible plants are found in rainforests but only 150 enter world commerce.
- Rainforest Crops include rice, quinine, rubber, coffee, bananas, eggplants, lemons, oranges, tea, cacao, cashews, cassava, tapioca, peanuts, pineapples, guavas, brazil nuts, paw paws, avocadoes and many more.
Biological and Genetic Resource
- Wild species have traits inadvertently bred out by selective breeding, thus domesticated plants and animals are more susceptible to pests and disease.
- As such genes from wild plants are used to fortify modern varieties, and are likely to become increasingly important for this purpose.
Medicines
- Rainforests are a vital source of medicines. Less than 1% of the world's tropical forest plants have been tested for pharmaceutical properties, yet at least 25% of all modern drugs came originally from rainforests, most first discovered and used by indigenous peoples.
- Annual worldwide sales of plant-derived pharmaceuticals currently total $20 billion e.g. Morphine and Quinine. 70% of all plants known to have anti-tumour properties come from tropical rainforests.
Existence Values
Homeland for Forest Peoples
- 500 million people live around tropical forests. Depending on the forests for products and services. For example, Rubber tappers are not indigenous to the forests of the Amazon but have learnt to live sustainably in the forest.
- There are 150 million indigenous people who rely on the forests for their way of life. The forests meet their economic needs for food and shelter and form an integral part of their culture and spiritual traditions.
- For more information visit: www.cifor.cgiar.org
Non-material Values
- The wonder and spiritual importance of the rainforests to all whom live in and around is profound. It is impossible to try to put a value on rainforests for all the riches they can and do offer.
Biodiversity
- This situation has been likened by biologists Anne and Paul Ehrlich to "an aeroplane losing the rivets which keep it together. No one knows how many rivets the plane can lose before it falls apart."
- For more information visit: www.iucn.org
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Science 
