Tropical and subtropical grasslands, savannas, and shrublands is a terrestrial biome defined by the World Wide Fund for Nature. [1] The biome is dominated by grass and/or shrubs located in semi-arid to semi-humid climate regions of subtropical and tropical latitudes. Tropical grasslands are mainly found between 5 degrees and 20 degrees in both North and south of the Equator. [2]
Grasslands are dominated by grasses and other herbaceous plants. Savannas are grasslands with scattered trees. Shrublands are dominated by woody or herbaceous shrubs.
Large expanses of land in the tropics do not receive enough rainfall to support extensive tree cover. The tropical and subtropical grasslands, savannas, and shrublands are characterized by rainfall levels between 90–150 centimetres (35–59 in) per year. [1] Rainfall can be highly seasonal, with the entire year's rainfall sometimes occurring within a couple of weeks.
African savannas occur between forest or woodland regions and grassland regions. Flora includes acacia and baobab trees, grass, and low shrubs. Acacia trees lose their leaves in the dry season to conserve moisture, while the baobab stores water in its trunk for the dry season. Many of these savannas are in Africa.
Large mammals that have evolved to take advantage of the ample forage typify the biodiversity associated with these habitats. These large mammal faunas are richest in African savannas and grasslands. The most intact assemblages currently occur in East African Acacia savannas and Zambezian savannas consisting of mosaics of miombo, mopane, and other habitats. [3] Large-scale migration of tropical savanna herbivores, such as wildebeest ( Connochaetes taurinus ) and zebra ( Equus quagga ), are continuing to decline through habitat alteration and hunting. [1] They now only occur to any significant degree in East Africa and the central Zambezian region. Much of the extraordinary abundance of Guinean and Sahelian savannas has been eliminated, although the large-scale migrations of Ugandan Kob still occur in the savannas in the Sudd region. [1] The Sudan type of climate is characterized by an alternating hot and rainy season, and a cool and dry season. In the Northern Hemisphere, the hot rainy season normally begins in May and lasts until September. Rainfall varies from 25 cm to 150 cm and is usually unreliable. The rest of the year is cool and dry. Rainfall decreases as one goes either towards North in Northern Hemisphere or South in the Southern Hemisphere. Drought is very common.
Tropical and subtropical grasslands, savannas, and shrublands occur on all continents but Antarctica. They are widespread in Africa, and are also found all throughout South Asia and Southeast Asia, the northern parts of South America and Australia, and the southern United States.
| Arnhem Land tropical savanna | Australia |
| Brigalow tropical savanna | Australia |
| Cape York Peninsula tropical savanna | Australia |
| Carpentaria tropical savanna | Australia |
| Einasleigh Uplands savanna | Australia |
| Kimberley tropical savanna | Australia |
| Mitchell grass downs | Australia |
| Trans-Fly savanna and grasslands | Indonesia, Papua New Guinea |
| Victoria Plains tropical savanna | Australia |
| Terai–Duar savanna and grasslands | Bhutan, India, Nepal |
| Western Gulf coastal grasslands | Mexico, United States |
| Beni savanna | Bolivia |
| Campos rupestres | Brazil |
| Cerrado | Bolivia, Brazil, Paraguay |
| Clipperton Island shrub and grasslands | Clipperton Island is an overseas territory of France |
| Córdoba montane savanna | Argentina |
| Guianan savanna | Brazil, Guyana, Venezuela |
| Humid Chaco | Argentina, Brazil, Paraguay, Uruguay |
| Llanos | Venezuela, Colombia |
| Uruguayan savanna | Argentina, Brazil, Uruguay |
| Hawaiian tropical high shrublands | Hawaiʻi |
| Hawaiian tropical low shrublands | Hawaiʻi |
| Northwestern Hawaii scrub | Hawaiʻi, Midway Atoll |
The Kalahari Desert is a large semi-arid sandy savanna in Southern Africa extending for 900,000 square kilometres (350,000 sq mi), covering much of Botswana, as well as parts of Namibia and South Africa.
In physical geography, a steppe is an ecoregion characterized by grassland plains without closed forests except near rivers and lakes. Steppe biomes may include:
Temperate grasslands, savannas, and shrublands is a terrestrial biome defined by the World Wide Fund for Nature. The predominant vegetation in this biome consists of grass and/or shrubs. The climate is temperate and ranges from semi-arid to semi-humid. The habitat type differs from tropical grasslands in the annual temperature regime as well as the types of species found here.
Sclerophyll is a type of vegetation that is adapted to long periods of dryness and heat. The plants feature hard leaves, short internodes and leaf orientation which is parallel or oblique to direct sunlight. The word comes from the Greek sklēros (hard) and phyllon (leaf). The term was coined by A.F.W. Schimper in 1898, originally as a synonym of xeromorph, but the two words were later differentiated.
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur naturally on all continents except Antarctica and are found in most ecoregions of the Earth. Furthermore, grasslands are one of the largest biomes on Earth and dominate the landscape worldwide. There are different types of grasslands: natural grasslands, semi-natural grasslands, and agricultural grasslands. They cover 31–69% of the Earth's land area.
A savanna or savannah is a mixed woodland-grassland ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. According to Britannica, there exists four savanna forms; savanna woodland where trees and shrubs form a light canopy, tree savanna with scattered trees and shrubs, shrub savanna with distributed shrubs, and grass savanna where trees and shrubs are mostly nonexistent.
Montane grasslands and shrublands are a biome defined by the World Wildlife Fund. The biome includes high elevation grasslands and shrublands around the world. The term "montane" in the name of the biome refers to "high elevation", rather than the ecological term that denotes the region below the treeline.
Tropical climate is the first of the five major climate groups in the Köppen climate classification identified with the letter A. Tropical climates are defined by a monthly average temperature of 18 °C (64.4 °F) or higher in the coolest month, and feature hot temperatures all year-round. Annual precipitation is often abundant in tropical climates, and shows a seasonal rhythm but may have seasonal dryness to varying degrees. There are normally only two seasons in tropical climates, a wet (rainy/monsoon) season and a dry season. The annual temperature range in tropical climates is normally very small. Sunlight is intense in these climates.
Rangelands are grasslands, shrublands, woodlands, wetlands, and deserts that are grazed by domestic livestock or wild animals. Types of rangelands include tallgrass and shortgrass prairies, desert grasslands and shrublands, woodlands, savannas, chaparrals, steppes, and tundras. Rangelands do not include forests lacking grazable understory vegetation, barren desert, farmland, or land covered by solid rock, concrete and/or glaciers.
The Miombo woodland is a tropical and subtropical grasslands, savannas, and shrublands biome located primarily in Central Africa. It includes four woodland savanna ecoregions characterized by the dominant presence of Brachystegia and Julbernardia species of trees, and has a range of climates ranging from humid to semi-arid, and tropical to subtropical or even temperate. The trees characteristically shed their leaves for a short period in the dry season to reduce water loss and produce a flush of new leaves just before the onset of the wet season with rich gold and red colours masking the underlying chlorophyll, reminiscent of autumn colours in the temperate zone.
The Llanos is a vast tropical grassland plain situated to the east of the Andes in Colombia and Venezuela, in northwestern South America. It is an ecoregion of the tropical and subtropical grasslands, savannas, and shrublands biome.
Burkina Faso is largely wild bush country with a mixture of grass and small trees in varying proportions. The savanna region is mainly grassland in the rainy season and semi desert during the harmattan period. Fauna, one of the most diverse in West Africa, includes the elephant, hippopotamus, buffalo, monkey, lions, crocodile, giraffe, various types of antelope, and a vast variety of bird and insect life. The country has 147 mammal species, 330 aquatic species including 121 species of fish and 2067 different plant species. Of the plant species, the dominant endemic species are shea tree and the baobab, the former plant species has immense economic value to the country.
The wildlife of Ivory Coast consists of the flora and fauna of this nation in West Africa. The country has a long Atlantic coastline on the Gulf of Guinea and a range of habitat types. Once covered in tropical rainforest, much of this habitat has been cleared, the remaining terrain being gallery forests and savanna with scattered groups of trees, resulting in a decrease in biodiversity. As of 2016, 252 species of mammal had been recorded in Ivory Coast, 666 species of bird, 153 species of reptile, 80 species of amphibian, 671 species of fish and 3660 species of vascular plant.
The biomes and ecoregions in the ecology of Zambia are described, listed and mapped here, following the World Wildlife Fund's classification scheme for terrestrial ecoregions, and the WWF freshwater ecoregion classification for rivers, lakes and wetlands. Zambia is in the Zambezian region of the Afrotropical biogeographic realm. Three terrestrial biomes are well represented in the country . The distribution of the biomes and ecoregions is governed mainly by the physical environment, especially climate.
The Victoria Plains tropical savanna is a tropical and subtropical grasslands, savannas, and shrublands ecoregion in northwestern Australia.
Mediterranean forests, woodlands and scrub is a biome defined by the World Wide Fund for Nature. The biome is generally characterized by dry summers and rainy winters, although in some areas rainfall may be uniform. Summers are typically hot in low-lying inland locations but can be cool near colder seas. Winters are typically mild to cool in low-lying locations but can be cold in inland and higher locations. All these ecoregions are highly distinctive, collectively harboring 10% of the Earth's plant species.
The Zambezian and mopane woodlands is a tropical and subtropical grasslands, savannas, and shrublands ecoregion of southeastern Africa.
Tropical vegetation is any vegetation in tropical latitudes. Plant life that occurs in climates that are warm year-round is in general more biologically diverse that in other latitudes. Some tropical areas may receive abundant rain the whole year round, but others have long dry seasons which last several months and may vary in length and intensity with geographic location. These seasonal droughts have great impact on the vegetation, such as in the Madagascar spiny forests.
The Southern Acacia–Commiphora bushlands and thickets is a tropical grasslands, savannas, and shrublands ecoregion in Tanzania and Kenya. It includes portions of Serengeti National Park and Ngorongoro Conservation Area, which are designated World Heritage Sites and biosphere reserves for their outstanding wildlife and landscapes. It is one of three Acacia–Commiphora bushlands and thickets ecoregions in eastern Africa.
This article incorporates text available under the CC BY-SA 3.0 license.World Wide Fund for Nature. "Tropical and Subtropical Grasslands, Savannas and Shrubland Ecoregions". Archived from the original on 2012-04-25. Retrieved 2019-05-29.
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