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New Page 7
Tropical
forests - past, present and future
The
world's tropical forests occur between the Tropics of Cancer and Capricorn, in
areas of high temperatures, plenty of sunshine and abundant rainfall. Tropical
forests are diverse; typically the forests are dense and layered, with openings
for the establishment of woody plants, palms, ferns and occasionally herbs. The
giant trunks and strong branches often carry a heavy epiphyte load of orchids
and bromeliads. Lianas climb and wind their way up the tree trunk and into the
openings in the high canopy. Many tropical plants, such as members of the genus
Passiflora, flower in the dry
season.
While, nutrient turnover rates are typically high in the forests the soils
remain rather nutrient poor. The rainforest food webs are often complex with
the rich flora providing an abundance of diverse plant material ranging from
nutritious seeds and fruit to juicy nectar and sap sources for countless
insects, reptiles, birds and mammals. Currently, this diversity is threatened
by man as the forests are much too often cleared on a destructively large
scale. This is one of the major reasons why the loss of tropical forests is
among the greatest
environmental threats facing humanity.
Further readings
Arnthorsdottir, S. 2008. On the
growth of lianas in a rainforests. Iceland Forestry,
2: 30-45 (in Icelandic).
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