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Exotics vs indigenous - Ecuador

Ecuador's coastal region stretches north-south, bordered by the Pacific Ocean to the west and the Andes chain to the east. The forest types vary from tropical to sub-tropical dry. Certain areas in the coast, most notably Los Rios province, have some of the most fertile soil in the world. Consequently, the region is very rich both in agriculture and forests. There is an extensive variety of indigenous trees in the coastal area. The indigenous species serves a wide variety of purposes and are very important to the Ecuadorian economy. There are two general wood categories, "madera buena" and "madera blanca."

There are numerous high quality madera buena species. Some of these are Cordia alliodora, Laures; Cedrela odorata, Cedro; Tabebuia chrysantha, Guayaium; and Sweitinia sp., Caoba. These species are prized for furniture, parquet floors, and other products requiring a fine, hard wood. Madera blanca is used for building houses and general construction. Ecuador provided 95% of the balsa used by the world before lightweight plastics became popular. Cana guadua is another wood product important to the coastal economy. It is used by the campesinos for cheap construction.

The varied indigenous trees of the coastal region are a rich natural resource. They provide the costanos with the raw material from which an infinite variety of wood products can be manufactured.

In the west where conditions are optimum for growth, fast growing exotic species are sometimes more economically appropriate than indigenous species. In recent years numerous exotic species have been introduced into Ecuador's coastal region. Tectona grandis, (Teca) is a high quality exotic species that is favored over indigenous ones of the same quality because of its rapid growth rate.

Other exotic species of particular interest are the trees of the family Leguminosae. The trees of this family provide a wide range of services to the environment they inhabit. Legumes are nitrogen fixers, their presence greatly improves soil fertility. These trees are extremely swift growers, providing varied wood products in a very short time. Legumes are adaptable to a wide range of site and soil conditions. They reproduce well and are easily cultivated. In addition to this, they are used as ornamentals and for shade. Legumes often provide food for animals (in the form of leaf forage and/or pods), and particular species provide food for human consumption. Legumes have exceptional recommendations for their exploitation in the hospitable environment of the coast. But the economic benefits exotic species provide need to be weighed against the possible deleterious effects of introducing exotic species into a different environment.

Monoculture plantations are one of the easiest methods of exotic species exploitation. When planting in a monoculture certain risks are taken. The introduced species brings with it none of the natural predator controls that exists in its indigenous environment. A pure stand of exotics is susceptible to disease and insect infestation. Insects and diseases can rapidly spread through a pure stand causing considerable damage to the species.

The original forest is often destroyed to make way for the monoculture plantation. Destruction of the indigenous forest can have far-reaching and often little understood effects on the local environment. When the indigenous forest is removed the habitat for many plants and animals is removed with it. In the environment of the sub-tropical and tropical forests, plants and animals have specialized niches. If the forest habitat is destroyed, it often cannot be replaced, and displaced plant and animal life may perish. This in turn may cause other environmental problems, for example, the depletion of certain gene pools. Deforestation is a leading cause of species extinction.

Some exotics are weed species in their natural environment. In a new environment there is potential for unchecked growth, taking over and crowding out ecologically important indigenous species.

Indigenous and exotic species both have an important place in Ecuador's coast. The ramifications of indigenous and exotic species exploitation on the ecology of the coast needs to be given serious consideration. Before decisions determining species use are made, tradeoffs may be necessary for the region's ecology and economy.