Content
Introduction
While a great deal of attention has focussed on the Amazon biome, another of Brazil's biome, the Atlantic Forest biome, has received much less attention. The forests in this biome have been reduced to about 11% of their former extent, making it a conservation priority. As a biome, it contains a variety of different vegetation types, ranging from topical rain forest to dry, open woodland and grassland. The biome has a very diverse flora and fauna, including more than 1000 bird species, 188 of which are endemic. There are 450 amphibians, with an astonishing 92% rate of endemism. The flora is equally diverse, and 20,000 tree species have been described, about half of which are endemic to the biome. Some of the forests are very diverse, with >450 tree species per hectare.
The lowland, submontane and montane forests are all considered to be seasonal moist tropical forests. Some of the most species rich are at mid-elevations, and the diversity of the forests generally increases northwards. Some of the southern forest types, such as the Araucaria forest are best classified as sub-tropical, and those at higher latitudes are warm temperate in nature. These forests tend to have lower diversity than some further north. In the rain shadow of the coastal ranges, the annual rainfall is only 700-1600 mm, and semideciduous and deciduous forests form a patchwork with cerrado.
Outcomes
By the end of this topic, you should be able to:
- List and describe the different ecoregions present in the Atlantic Forest biome
- Assess the role of rainfall in determining the forest types present in a given area
- Describe some of the endemic mammals present in this biome
- Suggest what the effects of deforestation and forest degradation may have been on the biota
Readings
Optional Readings
- Galindo-Leal, C. and Cámara I. de G. (eds.) 2003. The Atlantic Forest of South America. Biodiversity status, threats and outlook. Conservation International, Washington, DC, USA. 488 pp.
- Ridgely, R.S., Gwynne, J.A., Tudor, G. and Argel, M. 2016. Birds of Brazil. The Atlantic Forest of Southeast Brazil. Ithaca, New York, USA: Cornell University Press. 415 pp.
- Thomas, W.W. 2008. The Atlantic Coastal Forest of Northeastern Brazil. New York, USA: New York Botanical Garden. 586 pp.
Self-check Quiz (For certificate learning only)
After viewing topic presentations, take this self-check quiz to check your own progress. This quiz is designed to see how well you remember some of the issues presented in the topic. There are five questions, and each has a potential of 4 answers, only one of which is correct. When you are ready, click the link 'Self-check Quiz 5.1.15' to start taking the quiz.
Case Study Discussion (For certificate learning only)
Once you have have read the presentation, post a question about the ecology of the Brazil's Atlantic Forest, and answer/respond to at least one other question on the discussion board Case Study 15 Discussion - Brazil's Atlantic Rain Forest.
Summary
The Atlantic Forest biome consists of a wide range of different ecosystems, including mangrove forest, coastal restingas, tropical rain forest, semideciduous forest, deciduous forest and cerrado. It contains large numbers of endemic species, and >90% of the species within some taxonomic groups are endemic. The forest types reflect north-south and east-west gradients in climate, as well as soil type. This has resulted in a complex patchwork of habitats, especially in the interior. Almost 90% of the natural vegetation has been converted to other forms of land use, although the effects of this on the flora and fauna remain largely unknown.
Self-review (For self learning)
To review what you have learned in the topic, you are encouraged to use the following reflection questions as a study guide to do a self-review for the topic:
- Which ecoregions make up the Atlantic Forest biome, and what are their basic characteristics?
- How does the total amount and seasonal distribution of rainfall determine the different forest types present in a given area?
- What are some of the endemic mammals present in this biome?
- What effects do you think that deforestation and forest degradation have had on the biota of the Atlantic Forest?
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