Western Guinean lowland forests explained

Western Guinean lowland forests
Map:File:AT0130 map.png
Biogeographic Realm:Afrotropical
Biome:tropical and subtropical moist broadleaf forests
Border1:Eastern Guinean forests
Border2:Guinean forest-savanna mosaic,
Border3:Guinean mangroves
Area:203,842
Country1:Guinea
Country2:Ivory Coast
Country3:Liberia,
Country4:Sierra Leone
Coordinates:6.9°N -6.55°W
Conservation:Vulnerable
Global200:yes
Protected:24,028 km2
Protected Ref:[1]

The Western Guinean lowland forests ecoregion (WWF #AT0130) is a tropical moist broadleaf forest ecoregion of West Africa. It is centered on Liberia, with portions in surrounding countries. It is the westernmost tropical rainforest in Africa, and has high levels of species endemism, with over 200 species of endemic plants.[2] [3] [4] [5]

Geography

The ecoregion includes the lowland forests extending from the Atlantic Ocean a few hundred kilometres inland, and from western Côte d'Ivoire across Liberia, southeastern Guinea, most of Sierra Leone, and into southwest Guinea.

The terrain is relatively flat, with a mean elevation of 2,225 meters and a few isolated mountains that reach a high point of 1290m (4,230feet). Major rivers include the Sewa River, Mano River, Saint Paul River, Cavalla River and Sassandra River. The soils are poor, heavily leached lateritic.[2]

The Sassandra River of Côte d'Ivoire separates the Western Guinean forests from the Eastern Guinean forests which lie to the east. Inland and to the west, the Western Guinean forests transition to the Guinean forest-savanna mosaic, and to the Guinean montane forests at higher elevations.

The Western Guinean forests, together with the other tropical moist forests of West Africa, is included within Conservation International's Guinean Forests of West Africa biodiversity hotspot.

Climate

The climate of the ecoregion is Tropical savanna climate - dry winter (Köppen climate classification (Aw)). Temperatures can average from 30 to 33 degrees (C) in the hot months, 12 to 12 (C) in the colder months. The rainy season is May to October, with precipitation reaching 3,300 mm/year or more in the higher regions.[6] [7]

Flora and fauna

Closed forest covers two thirds of the ecoregion, mostly broadleaf evergreen trees, but much of this is second-growth or otherwise disturbed by human activities. Another 22% of the terrain is open forest or shrub. The term ‘farmbush’ has been applied to the degraded secondary growth that follows slash-and-burn agriculture.[2] Common trees include Dacroydes klaineana, Strombosia glaucescens, Allanblackia floribunda, Coula edulis and Diospyros sanza-minika.[2] Semi-deciduous forests occur at lower altitudes into Guinea.[2]

Because the wet areas expanded and contracted during the Ice Age, 'islands' of specialized species developed. Some of these areas of diversified floral and faunal communities are in protected areas.

Protected areas

A 2017 assessment found that 24,028 km2, or 12%, of the ecoregion is in protected areas. Only 2% of the unprotected area is covered by relatively-intact forest.[8] Protected areas include:

See also

External links

Notes and References

  1. Eric Dinerstein, David Olson, et al. (2017). An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm, BioScience, Volume 67, Issue 6, June 2017, Pages 534–545; Supplemental material 2 table S1b. https://doi.org/10.1093/biosci/bix014
  2. Web site: Western Guinean lowland forests. World Wildlife Federation. en. June 20, 2020.
  3. Web site: Map of Ecoregions 2017. Resolve. en. August 20, 2021.
  4. Web site: Western Guinean lowland forests. Digital Observatory for Protected Areas. en. August 20, 2021.
  5. Web site: Western Guinean lowland forests. The Encyclopedia of Earth. en. August 20, 2021.
  6. Web site: M. . Kottek . J. . Grieser . C. . Beck . B. . Rudolf . F. . Rubel . 2006 . World Map of Koppen-Geiger Climate Classification Updated. Gebrüder Borntraeger 2006. en. September 14, 2019.
  7. Web site: Dataset - Koppen climate classifications. World Bank. en. September 14, 2019.
  8. Eric Dinerstein, David Olson, et al. (2017). An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm, BioScience, Volume 67, Issue 6, June 2017, Pages 534–545; Supplemental material 2 table S1b. https://doi.org/10.1093/biosci/bix014