biological diversity of any geographical region is estimated at the level
of ecosystem diversity, species diversity and genetic diversity. Tripura
being a part of North-East India, belongs to one of the two “Hot Spot”
of India amongst 18 identified in the World. Hot Spots are designated
on the basis of evidences of present day distribution, diversity and linkages
of crop plants/ horticultural plants, with the past; Hot Spots are the
original homeland for evolution and distribution of such plants.
the ecosystem level, the State exhibits a part of Mountain ecosystem with
moderate hill ranges and forest ecosystem. In between these two dominant
ecosystems lies the freshwater ecosystem comprising 10 major rivers, numerous
wetlands. Undulating high lands of narrow and broken plates cover extensive
areas (Deb, 1975)
diversity at the species level is largely determined by ecosystem diversity,
which in turn is closely, linked with soil and climatic condition. The
species diversity of Tripura is largely known from Floral and Faunal diversity
range of floral diversity for a small state like Tripura appears significant
from the fact the nearly 1463 of the 17,000 species or 8.6% Angiosperms
(Flowering plants) known from India is recorded in Tripura (0.3% land
of India). A total of 1546 species other than Bacteria, Fungi, Mosses,
etc.) belonging to 862 genera and 192 families of Flora have been recorded
(Deb, 1981, 1983) of which 86% are widely distributed in India and adjoining
Flora of Tripura
[Source : Deb, 1981 & 1985]
is also interesting to note that the ratio of Monocot : Dicot species
for Tripura is much higher than for India (1:2.3 vis-à-vis 1:3.82).
Tripura belongs to the sub-zone Northern Burma (Hooker, 1909) which includes
Mizoram, Chittagounj Hills in Bangladesh and Arakan in Myanmar, besides
Andaman Islands. While a strong affinity with flora of Eastern Himalaya
can be noted, absence of Alpine flora of Abies,
Jumperus, Larix, Picia and Tsuga
is conspicuous; this can be attributed to climatic and altitudinal differences
which are conducive for such floral growth. On the other hand, a palm
species in Nepal and Sikkim is also recorded in Hilly terrain of Tripura.
the State, flora of northern region shows close affinity with adjacent
Barak valley flora of Assam and Sylhet area of Bangladesh. Of the other
areas, Sabrum region specially shows close affinity with flora of Chittagong
district of Bangladesh (Deb….).
Eastern Himalaya region is well known for high percentage of endemism
in flora and fauna. The State of Tripura, however, does not exhibit any
distinctive trait. Deb (…) opined that due to absence of scientific exploration
in the State in earlier period, many new taxa, which have wider distribution
into Tripura, were described from the adjoining regions. As such, no significant
endemicity in flora of Tripura could be noted.
Rare and Endangered Flora
Indian Wildlife (Protection) Act, 1972 amended till date include only
six plant species while the Red Data Book on Indian Plants published by
Botanical Survey of India contains data of more than 650 species considered
rare and endangered. At least 15 of such species recorded from Tripura
are known to be Rare or Threatened (Deb….). (Table-37).
37 : Rare and Threatened Taxa of
(1975-1981) provided a detailed account of plants of economic uses. Such
use pattern include manufacture of packing box (29 species), tea chest
(14 species), plywood (30 species), musical instrument (13 species), match
box (30 species), etc. A large number of species are used as timbers of
both high and low value. A list of timber producing species of Tripura
is given in Table-38.
producing Flora in Tripura
Besides timber, the
floral diversity of Tripura contributes significantly to the Bamboo and
Cane furniture and craft industry. At least 13 different bamboo species
and 6 cane species are known from the State (Table-39).
and Cane Species from Tripura
Nalini K. Chakrabarti, 2001 : Deb, op.cit]
estimate shows that at least 27 plant species contribute towards Non-Timber
Forest Produces (NTFP) including Tannin, Gum, Coloring material and others.
The estimate mentions about 107 species of plants used for fodder, 60
species of plants for human food and at least 65 species providing fruits
(Nalini Chakrabarti, Media article, Dainik Sambad, Agartala, 31st
January, 2001) While 628 species of plants from Tripura are reported to
contribute towards herbal medicines. 129 species are recognized in Indian
Pharmacopoeia; 61 of these species are recorded in Tripura, 26 as wild
plants and 35 under cultivated ones in the garden. Of the total of 628
plants, following Chopra’s Glossary of Medicinal plants. 403 species grow
in the wild while 225 species can be grown in the garden; of the wild
ones 143 are rare. A list of 158 medicinal plants of Tripura with local
names, parts used, occurrence, flowering and fruiting time is available
in Deb (1968, 1975). Latter Forest Department of Tripura reported documentation
and identification of around 266 species of medicinal plants (68 species
trees, 38 species shrubs, 71 species of herbs and 81 species of climbers).
A list of more important medicinal plants is given in Table-40.
: List of Selected Medicinal Plants
Eastern region occupies an important place with respect to agri-horticultural
biodiversity. This region has a large varities of agricultural crops,
viz., rice, maize, millets, beans and pulses, horticultural crops including
fruits viz. guava, ber, jackfruit, mango, papaya, vegetable crops viz.
brinjal, cucurbits, chillies, leafy vegetables, beans, colocasia and alocasia
possessing a significant genetic resource base. The most common families
of agri-horticultural species in Tripura and adjoining areas are given
– 41 :
Most common Families of Agri-horticultural Species
Eastern Region of India is well known as one of the 18 hotspot areas of
the world for agricultural biodiversity. Tripura being a part of north-east
India exhibit a rich varieties of rice germplasm which has been estimated
to be 118 (Sadana, S., Dutta M. and Dhiman Kr. ICAR Research Complex for
North East India, Tripura, personal communication). A total 119 cultivers
of local rice varieties collected from different parts of Tripura were
evaluated by the scientist of ICAR with reference to vigour, total number
of grains, hundred gain weight and single plant yield, etc. In grain yield
wide variation ranging from 0.18 to 22.68 gram was observed (single plant
yield). These germplasm have been conserved in the gene bank of National
Bureau of Plant Genetic Resources, New Delhi. No systematic programme
for on-farm conservation is existent.
Breeding Division of the Agriculture Department has collected and maintained
a germplasm of 29 wild varieties of rice, 5 of small millet (Kaon), 5
of maize, 1 of cotton, 1 of sesame, 1 of arhar, 2 of moong, and 2 of black
the beans and pulses, the region is quite rich and 10 species of beans
have been recorded and huge bio-type variation have been collected within
Eastern Region is regarded as a secondary centre for maize (Zea
maize) but 5 bio-types have been recorded in the Jhum areas of the
state. Local biotypes of brinjal and chilies are rich in Tripura. The
ICAR Centre has collected and catalouged 20 biotypes of brinjal and 16
biotypes of chilies.
and adjoining area of Bangladesh has 95-96 prominent vegetable species.
Cucurbits have as many as 17 species with a large number of varieties.
Sweet potato has two major types and within these types, 3-4 biotypes
have been recorded.
has six types in the state. Rhizotomatous crops belonging to family Araceae
have 6 species and 20 biotypes. Dioscorcaceae has 5 species with 23 biotypes,
which are generally found in upland and forest areas.
are 5 types of seasamums, 3 types of cotton and 5-6 types jute and mesta
lines native to Tripura.
State is quite rich in fruits and spice crops also. There are 60 fruit
crops cultivated in Tripura. The indigenous fruit crops have huge genetic
variety, viz. banana with good number of biotypes, jackfruit with 28 variables.
Other indigenous fruits included Amra, Guava, Ber, Gulapzam, Zamrul, Bael,
Satkara, Taal, Totka, Gaab, Kamranga, Sharifa, Chafta, Jalpai, Karamcha,
Dalim, Paniphal etc.
the State there are 27 species of spices available but most of them are
introduced other than chilies, zinger, cinnamon and turmeric; variability
available is restricted within these species only.
faunal diversity of the State can be viewed from Aquatic and Terrestrial
ecosystems. In the aquatic system, at least 129 species of fishes are
recorded belonging to 32 families, and 11 order, the largest number of
species being from the family Cyprinidae (49 species, including Rohu,
Katla, Kalbasu, Puthi, Mahasheer, Chela, etc.). it has been recorded that
the majority of the fishes are common to both Indo-Gangetic drainages
and South East Asian fish fauna. The occurrence of some marine and estuarine
fishes Pisodonophis boro, Tenualosa ilisha (Hilsa) (Hamilton),
Nematolosa nasus (Bloch) and Johnius
coitor (Hamilton) may be attributed with the riverine migration to
Meghna and Gumti system from
Bay of Bengal. The fishes of the State include 11 vulnerable species three
endangered species and three rare species (Table- 42). At 9 species endemic
to India are recorded from Tripura (Barman, R.P, Pisces, Fauna of Tripura,
Vol.–1, Zoological Survey of India, In Press). The amphibian are represented
by only two species while Reptiles are represented by 32 species including
three species of freshwater turtles and tortoises and three species of
water snakes. Besides the turtle aquatic snakes at least 13 species of
lizards including two species of monitor lizards, Varanus bengalensis (Daudin) and Varanus salvator (Laurenti) are known from Tripura; both the species
of varanus are endangered; at least 13 species of snakes other than the
aquatic snakes are known from the State of which Python molurus molurus (Linnaeus), common Indian Python is an endangered
species. (Sanyal, D.P., Dutta Gupta, B., and Gayen, N.C. Reptilia, Fauna
of Tripura, Vol.-1, Zoological Survey of India, In, Press).
No aquatic mammal has been recorded from the State.
Endangered and Rare Fish fauna in the State
invertebrate fauna include 27 species of Protzoans, 30 species of Crustaceans,
10 species of Rotifers, two species of annelids, 14 species of insects
(water beetles, bugs, Odonates, mosquitoes, etc.) and six species of Mollusca.
such the freshwater ecosystem of the State harbour a rich biodiversity
at different hierchial level including important food-species of fin fish
and shell fish. Recent investigation reveal a number of fish species have
become endangered including common species viz. Chana
striatus, C. marulius, labeo bata, L. pangasia, L. dero, Mystus seengala,
M. aor, Ompak pabda, O. bimaculatus, O. paba, Wallago autto, Natopterus
chitala, Macroganthus aculeatus, Mastacembelus armatus, enentodon concila,
Rita rita, Bagarius bagarius pangusius pangusius and Danio debario
due to changing water quality and
heavy silt load. Of all the species, Mahaseer, comprising of Tor
tor and Tor putitora fish appear to be most endangered in the State.
of aquatic system (provided by Prof. B.K. Agarwala, Tripura University)
are appended (Table-43). The total water resource area is given in Table-44.
Table-43 : Areas under land and water cover
Table- 44 : Aqua-bioresource Pattern
terrestrial fauna of Tripura appears equally rich in terms of species
fauna was reported to be composed 54 species (Bhattacharya, 1998) representing
9 orders. Forest Department, Government of Tripura (2000) recorded 90
mammalian species under 65 genera and 10 orders (Table-45). These represent
more than 33% of the total mammalian fauna known from India. Of the 15
primate species known from India 7 species have been recorded from Tripura
of which Phayre’s Leaf Monkey (locally known as “Chashma Banar”) is the
most dominant species. Endangered species of primates, besides Leaf Monkey
include Slow Loris, Stumped-tail Macaque, Pigtail Macaque and the only
tail less ape, Hollock Gibbon. Some of the mammalian species like common
Tree Shrew, Indian Bison, Chinese Pangolin is reported to be very rare,
while the population of Hoolock Gibbon, Indian Elephant and Jackal are
reported to be declining.
status (1989) of three mammalian species namely Leopard, Bison and Indian
Elephant show as total of 39 Leopards, 92 Bisons and 162 Elephants. While
Leopards and Elephants are recorded from North, South, West and Dhalai
district, Bisons are only recorded from South district.
Table- 45 : Land Mammal Genera & Species of Tripura compared with India
avian fauna is composed of 341 species belonging to 51 families of which
77 species are winter visitors. It may be noted that Tripura with only
0.4 percent of the total geographical area of India exhibits more than
25% of the avian species diversity of the country. Of the avian species
4 species belong to Schedule I and 271 species belong to Schedule IV of
the Indian Wildlife (Protection) Act, 1972, Amended till date.
reptilian fauna of Tripura is composed of 32 species under 28 genera and
11 families. These include 3 species of turtles and tortoise, 13 species
of lizards, and 15 species of snakes. At least three species of reptiles
are listed as endangered under Indian Wildlife (Protection) Act., 1972.
(Sanyal, D.P. et.al. Reptilia, Fauna of Tripura, Vol.-1, Zoological Survey
of India, In Press)
7.3 Rare and Threatened
Table- 46 : Rare and Threatened Fauna of Tripura
Domesticated Animal Species Diversity
detail information on the breeds of domesticated animal is available.
According Dept. of Animal
Resources Development, Govt. of Tripura, the population of indigenous
breed of cattle, buffalo (Raing and Manipuri) pig, goat (Black Bengal),
duck have been estimated during 1992 and 1997. An analysis of the data
shows more than 25% decline in indigenous cattle population nearly 50%
decline of indigenous buffalo population and pig population, nearly 40
decline of indigenous goat population and 30% decline in indigenous duck
population between 1992 and 1997. This trend should cause serious concern
and calls for an appropriate management
7.5 Biodiversity Conservation
State Government has set up a total of 4 Sanctuaries covering 604 sq.
km for in situ conservation.
One more Sanctuary in Athramura hill range is proposed to be notified.
It is to be noted that notification under 26(A) of Wildlife (Protection)
Act, 1972 are yet to be issued for all the four sanctuaries, while there
are already tremendous stress and man and animal conflict are reported
to be rise. Details of the four sanctuaries are given in following Table-47.
Table – 47 :
Sanctuaries in Tripura
Forest Department, Govt. of Tripura, 2000]
regard to ex situ conservation only one Zoological garden has been established
in Sephalijila. The Zoo contains 408 animals belonging 46 different species
of fauna. Captive breeding programmes of some selected species including
Leopard cat, Spotted Dear and Primates have been initiated.
a centrally sponsored scheme on “non-timber forest produce including medicinal
plants” more than 500 ha of plantation is being raised with trees having
medicinal values, in degraded forest land. The species grown include Arjun,
Bahera¸ Palas, Haritaki, Amla, Neem, etc.
7.6 Problems relating
to Biodiversity Conservation
Habitat Destruction :
of land use due to conversion of forest for non forestry purposes specially
to meet the demand of plantation crops and development activities cause
serious concern for and degradation of wildlife habitat. No quantified
data is available on annual or decadal basis for such conversion activities.
is no pasture land in the state for livestock grazing. It is estimated
that 60% of the livestock graze in the forest land. This far exceeds the
carrying capacity of the forests and causes destruction of young growth
of the forest and destruction of habitat for the wild animals.
fires are common and frequent in the state. It is now estimated that forest
fire is common in 20 percent of the total forest area of Tripura. The
major causes may be intentional burning of ground cover for grazing or
for jhum cultivation. This led to complete wiping out the forest regeneration
in some areas, (natural as well as artificial) and wildlife is severely
slash and burn cultivation in the hill tribal areas has direct impact
on biodiversity viz. destruction of wildlife and natural habitat, loss
of natural forest and loss of ecological balance including destruction
of feeding, breeding and roosting grounds.
Introduction of Exotic Species
to change in agricultural practices and emphasis in food security a number
of plant species have been introduced in Tripura. It is estimated that
280 species of plant have been introduced in the state during the past
period. The impact of such introduction has never been assessed but it
may be assumed that in number of local indigenous varieties have become
rare or have disappeared due to introduction of exotics.
7.6.6 IIIegal Hunting
The conservation of biodiversity depend on strict protective measures in the field condition besides, appropriate legal instrument. Due to disturbed geopolitical condition, it is apprehended that illegal hunting pressure has increased in many remote and isolated dense forest areas. In absence of lack of appropriate monitoring and surveillance mechanism, the human pressure on wildlife may continue to increase.