Deccan thorn scrub forests
Encyclopedia
The Deccan thorn scrub forests is a xeric shrubland
ecoregion
of India
and northernmost Sri Lanka
, a large area that was once forest and home to large numbers of elephants and tigers.
, extending across the Indian states of Maharashtra
, Karnataka
, Andhra Pradesh
, and Tamil Nadu
to the Northern Province
of Sri Lanka. Only small patches of natural habitat remain as most of the region has been cleared for grazing land.
The annual rainfall is less than 750 mm (29.5 in), all falling during the short rainy season and the area receives no rainfall during the months of November to April. Temperatures can exceed 40 °C (104 °F) during the hotter months.
, Eremopogon foveolatus, Aristida setacea, and Dactyloctenium
species.
The second story of the Deccan thorn scrub forests in India is poorly developed and mainly consists spiny and xerophytic species, mostly shrubs. An ill-defined lower story can also be discerned, during the brief wet season. The plant species that dominate the vegetation in these forests are Acacia species, Balanites roxburghii
, Cordia myxa
, Capparis
spp., Prosopis
spp., Azadirachta indica, Cassia fistula, Diospyros chloroxylon, Carissa carandas, and Phoenix sylvestris
. There are also several other habitat types found in these forests.
The driest, rockiest areas of the ecoregion are covered with a scrub dominated by species of Euphorbia. The soil is usually bare in these areas; however, some grassy growth may also appear during the short monsoon season
.
The parts of the ecoregion found in Tamil Nadu receive even less rainfall than most and the vegetation in these parts is mainly made up of thinly spread thorny forests of Acacia planifrons, which are characterised by umbrella-shaped crowns.
The remaining patches of forest are also home to a large number of plants, some of medicinal and botanical interest, including an endemic cycad (Cycas beddomei
) and Psilotum nudum
. A small patch of the tree Shorea talura also exists within the Chittoor forest division, part of which is being maintained as a preservation plot by the Forest Department of Andhra Pradesh.
Finally, the area between the Nallamala and Seshachalam Hills
is well known for the Red Sanders (Pterocarpus santalinus
), a rare, endemic tree species that is harvested for the medicinal value of its wood.
(Ardeotis nigriceps) and Blackbuck
(Antilope cervicapra), although these and other species are declining in number.
The forests used to provide habitat to two prominent mammal species, the Bengal tiger
(Panthera tigris tigris) and the Indian Elephant
(Elephas maximus indicus), until recently but their populations have dwindled and even become locally extinct. The ecoregion and is the southern limit of the Nilgai
antelope (Boselaphus tragocamelus).
The ecoregion is home to a total of ninety-six mammal fauna species, out of which, three are considered endemic: Split Roundleaf Bat (Hipposideros schistaceus), Kondana Soft-furred Rat
(Millardia kondana), and Elvira Rat
(Cremnomys elvira). Other threatened mammal species found in these forests include the tiger, gaur
(Bos gaurus), Dhole
(Cuon alpinus), Sloth Bear
(Melursus ursinus), Chousingha (Tetracerus quadricornis), and Blackbuck (Antilope cervicapra).
The Deccan Thorn scrub forests are home to a richer variety of birds, almost 350 species of which three are considered near-endemic: Jerdon's Courser
(Rhinoptilus bitorquatus), Sri Lanka Junglefowl
(Gallus lafayetii), and Yellow-fronted Barbet
(Megalaima flavifrons). Among these, the Jerdon's Courser is also considered a globally threatened species, and was rediscovered in this ecoregion in 1986 after being recorded for the last time in 1900. Other globally threatened bird species such as the Lesser Florican
(Sypheotides indicus) and Indian Bustard can also be found in the ecoregion.
in Kurnool
, Andhra Pradesh.
Deserts and xeric shrublands
Deserts and xeric shrublands is a biome characterized by, relating to, or requiring only a small amount of moisture.-Definition and occurrence:...
ecoregion
Ecoregion
An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...
of India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and northernmost Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
, a large area that was once forest and home to large numbers of elephants and tigers.
Location and description
This ecoregion covers the arid portions of the Deccan PlateauDeccan Plateau
The Deccan Plateau is a large plateau in India, making up the majority of the southern part of the country. It rises a hundred meters high in the north, rising further to more than a kilometers high in the south, forming a raised triangle nested within the familiar downward-pointing triangle of...
, extending across the Indian states of Maharashtra
Maharashtra
Maharashtra is a state located in India. It is the second most populous after Uttar Pradesh and third largest state by area in India...
, Karnataka
Karnataka
Karnataka , the land of the Kannadigas, is a state in South West India. It was created on 1 November 1956, with the passing of the States Reorganisation Act and this day is annually celebrated as Karnataka Rajyotsava...
, Andhra Pradesh
Andhra Pradesh
Andhra Pradesh , is one of the 28 states of India, situated on the southeastern coast of India. It is India's fourth largest state by area and fifth largest by population. Its capital and largest city by population is Hyderabad.The total GDP of Andhra Pradesh is $100 billion and is ranked third...
, and Tamil Nadu
Tamil Nadu
Tamil Nadu is one of the 28 states of India. Its capital and largest city is Chennai. Tamil Nadu lies in the southernmost part of the Indian Peninsula and is bordered by the union territory of Pondicherry, and the states of Kerala, Karnataka, and Andhra Pradesh...
to the Northern Province
Northern Province, Sri Lanka
The Northern Province is one of the 9 provinces of Sri Lanka. The provinces have existed since the 19th century but did not have any legal status until 1987 when the 13th Amendment to the 1978 Constitution of Sri Lanka established provincial councils. Between 1988 and 2006 the province was...
of Sri Lanka. Only small patches of natural habitat remain as most of the region has been cleared for grazing land.
The annual rainfall is less than 750 mm (29.5 in), all falling during the short rainy season and the area receives no rainfall during the months of November to April. Temperatures can exceed 40 °C (104 °F) during the hotter months.
Flora
Today the remaining patches of forest are mostly of southern tropical thorn scrub type , they also include patches of the original vegetation, tropical dry deciduous forests. The southern tropical thorn scrub type forests consist of open, low vegetation that is characterised by thorny trees with short trunks and low, branching crowns that rarely meet to form a closed canopy. In this vegetation, the trees attain maximum heights of 6 –. Typical grasses of the ecoregion include Chrysopogon fulvus, Heteropogon contortusHeteropogon contortus
Heteropogon contortus is a tropical, perennial tussock grass with a native distribution encompassing Southern Africa, southern Asia, Northern Australia and Oceania. The species has also become a naturalised weed in tropical and subtropical regions in the Americas and East Asia. The plant grows to ...
, Eremopogon foveolatus, Aristida setacea, and Dactyloctenium
Dactyloctenium
Dactyloctenium is a grass genus in the family Poaceae. The approximately ten species in this genus are collectively known as crowfoot grasses...
species.
The second story of the Deccan thorn scrub forests in India is poorly developed and mainly consists spiny and xerophytic species, mostly shrubs. An ill-defined lower story can also be discerned, during the brief wet season. The plant species that dominate the vegetation in these forests are Acacia species, Balanites roxburghii
Balanites roxburghii
Balanites roxburghii is a spiny, evergreen tree. It is common in open sandy plains of the Indian peninsula, western Rajasthan, west Bengal, Maharashtra and drier parts of India.- Names :...
, Cordia myxa
Cordia myxa
Cordia myxa is a species of flowering plant in the borage family, Boraginaceae. It is a medium-sized broad-leaved deciduous tree. Common names include لسوڑا, Lasura, Assyrian Plum, Pidar, Panugeri, Naruvilli, Geduri, Spistan, and Burgund dulu wanan...
, Capparis
Capparis
Capparis is a flowering plant genus in the family Capparaceae which is included in the Brassicaceae in the unrevised APG II system. These plants are shrubs or lianas and are collectively known as caper shrubs or caperbushes...
spp., Prosopis
Prosopis
Prosopis is a genus of flowering plants in the pea family, Fabaceae. It contains around 45 species of spiny trees and shrubs found in subtropical and tropical regions of the Americas, Africa, Western Asia, and South Asia. They often thrive in arid soil and are resistant to drought, on occasion...
spp., Azadirachta indica, Cassia fistula, Diospyros chloroxylon, Carissa carandas, and Phoenix sylvestris
Phoenix sylvestris
Phoenix sylvestris also known as Silver Date Palm or Sugar Date Palm, is a species of flowering plant in the palm family native to southern Pakistan,most of India and Bangladesh. Growing in plains and scrubland to 1300 m, the fruit from this palm species is used to make wine and jelly...
. There are also several other habitat types found in these forests.
The driest, rockiest areas of the ecoregion are covered with a scrub dominated by species of Euphorbia. The soil is usually bare in these areas; however, some grassy growth may also appear during the short monsoon season
Monsoon of Indian subcontinent
A Monsoon of the India is among the several geographically distributed observations of the global monsoons. In the subcontinent, it is one of oldest weather observations, an economically important weather pattern and the most anticipated weather event and unique weather phenomenon. Yet it is only...
.
The parts of the ecoregion found in Tamil Nadu receive even less rainfall than most and the vegetation in these parts is mainly made up of thinly spread thorny forests of Acacia planifrons, which are characterised by umbrella-shaped crowns.
The remaining patches of forest are also home to a large number of plants, some of medicinal and botanical interest, including an endemic cycad (Cycas beddomei
Cycas beddomei
Cycas beddomei is a species of cycad in the genus Cycas, native to India, where it is confined to a small area of Andhra Pradesh state in the Cuddapah Hills in scrubland and brush covered hills....
) and Psilotum nudum
Psilotum nudum
Psilotum nudum is a fern plant. Like the other species in the order Psilotales, it lacks roots. It is found in tropical Africa, Central America, tropical and subtropical North America, South America,, tropical Asia, Australia, Hawaii, southern Japan, Lord Howe Island, New Zealand, with a few...
. A small patch of the tree Shorea talura also exists within the Chittoor forest division, part of which is being maintained as a preservation plot by the Forest Department of Andhra Pradesh.
Finally, the area between the Nallamala and Seshachalam Hills
Seshachalam Hills
The Seshachalam Hills are hilly ranges part of the Eastern Ghats in southern Andhra Pradesh state, in southeastern India. The ranges were formed during the Precambrian era . Minerals contained in these hills include sandstone and shale interbedded with limestone...
is well known for the Red Sanders (Pterocarpus santalinus
Pterocarpus santalinus
Pterocarpus santalinus , ; Red Sanders or Red Sandalwood) is a species of Pterocarpus native to India. It is only found in south India in Kadapa and Chittoor on the Tamil Nadu and Andhra Pradesh border....
), a rare, endemic tree species that is harvested for the medicinal value of its wood.
Fauna
The dry grasslands that predominate do provide habitat for the native fauna remaining scattered amid the thorn scrub. The grasslands of southern Andhra Pradesh support a good population of the Great Indian BustardGreat Indian Bustard
The Great Indian Bustard or Indian Bustard is a bustard found in India and the adjoining regions of Pakistan. A large bird with a horizontal body and long bare legs giving it an ostrich like appearance, this bird is among the heaviest of the flying birds...
(Ardeotis nigriceps) and Blackbuck
Blackbuck
Blackbuck is a species of antelope native to the Indian subcontinent. Their range decreased sharply during the 20th century. Since 2003, the IUCN lists the species as near threatened....
(Antilope cervicapra), although these and other species are declining in number.
The forests used to provide habitat to two prominent mammal species, the Bengal tiger
Bengal Tiger
The Bengal tiger is a tiger subspecies native to the Indian subcontinent that in 2010 has been classified as endangered by IUCN...
(Panthera tigris tigris) and the Indian Elephant
Indian Elephant
The Indian Elephant is one of three recognized subspecies of the Asian elephant, and native to mainland Asia. Since 1986, Elephas maximus has been listed as endangered by IUCN as the population has declined by at least 50% over the last three generations, estimated to be 60–75 years...
(Elephas maximus indicus), until recently but their populations have dwindled and even become locally extinct. The ecoregion and is the southern limit of the Nilgai
Nilgai
The nilgai , sometimes called nilgau, is an antelope, and is one of the most commonly seen wild animals of central and northern India and eastern Pakistan; it is also present in parts of southern Nepal. The mature males appear ox-like and are also known as blue bulls...
antelope (Boselaphus tragocamelus).
The ecoregion is home to a total of ninety-six mammal fauna species, out of which, three are considered endemic: Split Roundleaf Bat (Hipposideros schistaceus), Kondana Soft-furred Rat
Kondana Soft-furred Rat
The Kondana Soft-furred Rat is a species of rodent in the family Muridae.It is found only in India.Its natural habitats are subtropical or tropical dry forests, subtropical or tropical dry lowland grassland, and urban areas....
(Millardia kondana), and Elvira Rat
Elvira Rat
The Elvira Rat is a species of rodent in the family Muridae.It is found only in India.Its natural habitat is subtropical or tropical dry shrubland.-References:* CBSG CAMP Workshop, India 2000. . Downloaded on 9 July 2007....
(Cremnomys elvira). Other threatened mammal species found in these forests include the tiger, gaur
Gaur
The gaur , also called Indian bison, is a large bovine native to South Asia and Southeast Asia. The species is listed as vulnerable on the IUCN Red List since 1986 as the population decline in parts of the species' range is likely to be well over 70% over the last three generations...
(Bos gaurus), Dhole
Dhole
The dhole is a species of canid native to South and Southeast Asia. It is the only extant member of the genus Cuon, which differs from Canis by the reduced number of molars and greater number of teats...
(Cuon alpinus), Sloth Bear
Sloth Bear
The sloth bear , also known as the labiated bear, is a nocturnal insectivorous species of bear found wild within the Indian subcontinent. The sloth bear evolved from ancestral brown bears during the Pleistocene and shares features found in insect-eating mammals through convergent evolution...
(Melursus ursinus), Chousingha (Tetracerus quadricornis), and Blackbuck (Antilope cervicapra).
The Deccan Thorn scrub forests are home to a richer variety of birds, almost 350 species of which three are considered near-endemic: Jerdon's Courser
Jerdon's Courser
The Jerdon's Courser is a nocturnal bird belonging to the pratincole and courser family Glareolidae endemic to India. The bird was discovered by the surgeon-naturalist Thomas C. Jerdon in 1848 but not seen again until its rediscovery in 1986. This courser is a restricted-range endemic found...
(Rhinoptilus bitorquatus), Sri Lanka Junglefowl
Sri Lanka Junglefowl
The Sri Lankan Junglefowl , also known during the colonial era as the Ceylon Junglefowl, is a member of the pheasant family which is endemic to Sri Lanka, where it is the national bird. It is closely related to the Red Junglefowl , the wild junglefowl from which the chicken was domesticated...
(Gallus lafayetii), and Yellow-fronted Barbet
Yellow-fronted Barbet
Yellow-fronted Barbet is an Asian barbet which is an endemic resident breeder in Sri Lanka. Barbets and toucans are a group of near passerine birds with a worldwide tropical distribution...
(Megalaima flavifrons). Among these, the Jerdon's Courser is also considered a globally threatened species, and was rediscovered in this ecoregion in 1986 after being recorded for the last time in 1900. Other globally threatened bird species such as the Lesser Florican
Lesser Florican
The Lesser Florican , also known as the Likh, is a large bird in the bustard family and the only member of the genus Sypheotides. It is endemic to the Indian Subcontinent where it is found in tall grasslands and is best known for the leaping breeding displays made by the males during the Monsoon...
(Sypheotides indicus) and Indian Bustard can also be found in the ecoregion.
Threats and conservation
The remaining deciduous woodland continues to be cleared for grazing land, while the pasture that has been created is itself threatened by overgrazing and invasive weeds. One large area of natural forest remains in southern Andhra Pradesh and there eleven protected areas but all of them small, the largest being the Rollapadu Bird Sanctuary for the Great Indian Bustard near NandikotkurNandikotkur
Nandikotkur is a town and mandal in Kurnool district of Andhra Pradesh, India.-Geography:Nandikotkur is located at . It has an average elevation of 292 meters ....
in Kurnool
Kurnool
Kurnool is located at . It has an average elevation of 273 metres .Kurnool lies on the banks of the Tungabhadra River. The Handry and Neeva rivers also flow through the city. The K.C...
, Andhra Pradesh.