Angiosperms of Sendirakillai Sacred Grove ( SSG ) , Cuddalore District , Tamil Nadu , India

Materials and Methods Study Site Sendirakillai Sacred Grove (SSG) is a community (Vanniyas) conserved TDEF fragment located on the Coromandel Coast of Cuddalore district (11°44’24” N, 79°47’24” E), Tamil Nadu, South India (Figure 1 and 2). It occupies an area of 3.5 ha. The sacred grove receives an annual rainfall of about 1080 mm. The minimum day temperature of the sacred grove is 22.75°C and the maximum is 33.64°C. Folk deities such as Muniyanar, Muthalraathan, Ponniamman and Iyanar are present in the sacred grove (Figure 3). There is a canal which carries excess water discharged from the Veeranam Lake and bisects the sacred grove. The vegetation of the sacred grove that occurs east of the canal is comparatively more open and more disturbed than that of western side, though this portion harbours all the four deities. The entire grove is surrounded by cashew plantations and agriculture and floriculture fields.


Introduction
Sacred groves are patches of relict vegetation that are usually associated with folk deities and are conserved by the local communities based on taboos, religious beliefs and social sanctions (Gadgil and Vartak 1975).The plant richness and conservation potential of sacred groves are impressive enough to recognize them as 'Mini Biosphere Reserve' (Gadgil and Vartak 1975).Tropical Dry Evergreen Forest (TDEF) is one of the 16 major forest types in India and it is distributed in a narrow strip along the coast of Andhra Pradesh and Tamil Nadu.Champion and Seth (1968) state that these forests "have been influenced by felling, lopping and browsing and have become irregular with open patches, and the thorny and unpalatable species have largely displaced the climax vegetation".Considerable areas of this forest type have long been significantly degraded and fragmented (Selvamony et al. 1999) and nearly 80% of the remnants are conserved as sacred grove excluding a few Reserve Forests (RFs) and academic institution campuses.Hence, it should be considered as one of the endangered forest types in India.Plant Taxonomists and Ecologists have long been studying this forest type in different aspects such as assessment of its phytodiversity, documentation of ethnobotanically important plant species and analyzing its vegetation structure (Meher-Homji 1974;Parthasarathy and Karthikeyan 1997;Ramanujam and Kadamban 2001;Ramanujam and Cyril 2003;Reddy and Parthasarathy 2003;Venkateswaran and Parthasarathy 2003;Venkateswaran and Parthasarathy 2005;Parthasarathy et al. 2008;Udayakumar and Parthasarathy 2010).The present study was carried out with the following objectives: (i) To prepare a checklist of plant species of the sacred grove; (ii) To document threatened and endemic taxa of the sacred grove; Abstract: We provide a checklist of Angiosperm alpha diversity of Sendirakillai Sacred Grove (SSG), a community conserved Tropical Dry Evergreen Forest (TDEF) fragment located on the Coromandel Coast of Cuddalore district (11°44'24" N, 79°47'24" E), Tamil Nadu, South India.Plant specimens were collected either with flowers or fruits and were identified and confirmed with available regional floras, revisions and monographs.In the present study, we have enumerated a total of 180 species and 2 varieties belonging to 151 genera distributed in 66 families from 29 orders according to Angiosperm Phylogeny Group III Classification.More than 30% of the total flora is represented by six families namely Fabaceae (14), Rubiaceae (12), Cyperaceae (10), Apocynaceae (8), Poaceae (8) and Euphorbiaceae (7).Three endemic species to India and three species that are confined to peninsular India and Sri Lanka are recorded from the sacred grove.Threats to the biodiversity of sacred grove are identified and conservation strategies are proposed.Pradeep 1996 ;Singh 2000;2001;2005).Photographs were taken for some of the more common, very rare, ethno-botanically valuable and endemic plant species in the sacred grove.Abbreviations of author's names of plant names strictly follow Brummitt and Powell (1992).The standard herbarium technique given by Fosberg and Sachet (1965) was followed for preparation of herbarium specimens.Herbarium specimens are deposited at Madras Christian College Herbarium (MCCH), Chennai, for further reference.

Results and Discussion
In the present study, a total of 180 species and 2 varieties belonging to 151 genera distributed in 66 families from 29 orders according to Angiosperm Phylogeny Group III Classification (2009) have been recorded from the sacred grove and are represented in table 1.More than 80% of the flora is represented by orders of Eudicot and Core Dicot, of which the major contributions are from Gentianales (12%), Malphigiales (10%), Lamiales (9%), Fabales (9%) and Caryophyllales (8%) of the sacred grove (Figure 4 and 5).Similarly more than half of the monocot taxa are represented by a single order namely Poales (56%).More than 30% of the total flora is represented by six families, viz., Fabaceae (14), Rubiaceae (12), Cyperaceae (10), Apocynaceae (8), Poaceae (8) and Euphorbiaceae (7).Occurrence of more members of Cyperaceae and Poaceae is probably due to the presence of agricultural and floricultural fields in the surrounding.An analysis on the life form composition of the flora shows that 65% are herbaceous that include herbs and herbaceous climbers and the remaining 35% consist of woody life forms that include trees, shrubs and lianas (Figure 6).A total of eight orders namely Alismatales, Asparagales, Asterales, Celastrales, Cucurbitales, Dioscoreales, Magnoliales and Santalales are represented by two species each and four orders namely Liliales, Pandanales, Piperales and Zygophyllales are represented just by a single species.Genera such as Cleome, Phyllanthus and Cyperus are with maximum species diversity and are distributed with four species each.A scrutiny of literature (Ahmedullah and Nayar 1987;Nair and Nayar 1997;Singh 2000;Dutta and Deb 2004;Balakrishnan and Chakrabarthy 2007) pertaining to endemism reveals that three species namely Jatropha tanjorensis, Leucas diffusa and Sansevieria roxburghiana are endemic to India and three species, viz., Capparis rotundifolia, Hedyotis graminifolia and Pamburus missionis are endemic to peninsular India and Sri Lanka.The presence of these endemic species indicates the importance of conservation of sacred grove.
The vegetation of the sacred grove is characterized by most of the TDEF tree species such as Atalantia monophylla, Garcinia spicata, Lepisanthes tetraphylla, Memecylon edule and Pterospermum canescens; liana namely Cissus vitiginea, Combretum albidum and Reissantia indica and shrubs include Canthium coromandelicum, Capparis brevispina, Carissa spinarum, Glycosmis mauritiana, Securinega leucopyrus and Tarenna asiatica.It is also an abode for some of the rare plant species such as Polyalthia korintii, Phyllanthus rotundifolius and Capparis rotundifolia (Mitra 1993;Nair and Nayar 1997;Balakrishnan and Chakrabarthy 2007).Dendrophthoe falcata is the only parasitic plant species found in the sacred grove, which grows on the branches of Lannea coromandelica.Theriophonum minutum and Sansevieria roxburghiana are the only two plant species that form the ground vegetation of the sacred grove.Salix tetrasperma, a typical riparian element is represented only by an individual tree and presence of few individuals of Calophyllum inophyllum in the sacred grove are probably the remnants of the past vegetation.Apart, it harbours many psammophytic species such as Allmania nodiflora, Bulbostylis barbata, Cleome monophylla, Cyperus arenarius, Euphorbia rosea, Mollugo cerviana and M. disticha.The three Ficus species namely F. amplissima, F. benghalensis and F. hispida found in the sacred grove act as keystone species by providing food and shelter for many birds and insects (Figure 7 (Ramanujam and Kadamban 2001;Ramanujam and Cyril 2003).A comparison of phytodiversity of the SSG with the above mentioned sacred groves reveals that the SSG has the highest plant diversity.
The considerable reduction in the size of the sacred grove is due to encroachment of land for agriculture, floriculture and also for cashew plantation.It seems to be a major factor that destroys the sacred groves and sizable portions of the sacred grove have been cleared in the past and are still being cleared.The firewood is being collected from the grove only from the dry branches and stump of the lopped trees were also observed in several places of the sacred grove which indicate the anthropogenic disturbance (Figure 15).The vehicular traffic, especially bullock cart and tractor, for carrying the agricultural goods result in gradual expansion of the pathway in the sacred grove.During the present study we also observed a large scale collection of leaves of Garcinia spicata in the sacred grove by outsiders for prawn cultivation, which may interfere the growth and reproduction of these trees.
The SSG is a comparatively well-conserved grove covering an area of 3.5 ha. with rich phytodiversity and a proportionately good number of endemics.The high level of species richness is a testimony to the health of the sacred grove.This culturally conserved patch of natural vegetation acts as (i) Asylum for relict species; (ii) Habitat for endemic and threatened species that require a specific microclimate; (iii) Seed bank for the TDEF species; (iv) Medicinal treasure for the local communities; (v) Habitat for a wide-range of organisms and; (vi) Knowledge Centre for the neighborhood community as well for students/researchers in continuing oral traditional knowledge on plants; (vii) A centre for social and religious gathering to build relationship among the community members.
Hence it is suggested that SSG may be proposed as a Biodiversity Heritage Site as envisaged by the National Environmental Policy and it has already been initiated by National Biodiversity Authority (NBA) by establishing Biodiversity Management Committee (BMC).The awareness on the importance of the sacred grove needs to be created among the local people for the effective conservation.As Gadgil (1994) emphasized the necessity of National Level Sacred Grove Act for the conservation of sacred groves in India it is inevitable and it is also important to study and map the existing sacred groves in India with the help of Geographical Information System (GIS) to develop effective conservation strategies throughout the country.

Figure 2 .
Figure 2. A) Path way inside the Sacred Grove; B) A view of near by Cashew Plantation; C) Entrance view of the Sacred Grove; D) A Canal which bisects the Sacred Grove.

Figure 3 .
Figure 3. A) Front view of Muniyanar temple, the largest structural temple of the sacred grove; B) Iyanar temple with a low concrete shelter; C) Newly built Muthalraathan temple. -14).

Figure 4 .
Figure 4. Representation of major groups/clade in the flora of Sendirakillai Sacred Grove.

Figure 5 .
Figure 5. Species diversity (in percentage) in various orders of the flora of Sendirakillai Sacred Grove.

Figure 6 .
Figure 6.Life form composition of Sendirakillai Sacred Grove.