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21.
In this study we have tried to link a quantitative inventory of deforestation to possible factors driving forest clearing, like accessibility and soil quality. The Study Area covered 395 km2 in the Atlantic Zone of Costa Rica. Basic information came from aerial photographs taken in 1952, 1960, 1971 to 73, 1981 and 1984. Photo interpretations were digitized and processed with the help of a monoplotting programme. Three phases in deforestation were distinguished:
  • 1 The period before 1960, characterized by a gradual increase in the rate of deforestation, with preferential clearing along rivers and on fertile soils.
  • 2 The period 1960-1972. This period shows an increased clearing rate caused by a new centre of colonization, Cariari. Furthermore, banana plantations entered the area and main roads were constructed. Deforestation took place preferentially along roads and on fertile soils.
  • 3 In the period 1972-1984 the remaining forest ‘islands’ were cleared at an accelerated rate. This was because only small areas of forest were left by this period. Also between 1972 and 1984 the fertile soils were cleared most rapidly.
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