Diversity status of the family , Euphorbiaceae in about 30 km radius of Kudankulam Nuclear Power Project area , Southern India

A detailed Euphorbiaceae flora study was carried out from 30 km radius of Kudankulam Nuclear Power Project area. The survey was conducted from September 2012 to August 2013. A total of 32 species under 12 genera belonging to the family Euphorbiaceae were collected and identified. For each species, botanical name, local name, life-form, habitat and flowering season were mentioned. A statistical summary is presented at the end of the checklist. The area shows a high diversity in its terrestrial flora and has an important role in the conservation of biodiversity of the region.


Study area
The site for Kudankulam Nuclear Power Project (KKNPP) is situated in Kudankulam Village, Tirunelveli district, Tamil Nadu, India.The site is on the shore of the Gulf of Mannar and is located near the South eastern tip of India.The study area covered is 30 km radius of KKNPP.The study area lies between latitudes 8° 5 to 8° 28 of North and longitudes 77° 28 to 77° 57 of East in the terrestrial region including fresh water and wetlands.The nearest village to the site is Kudankulam and Idinthakarai.The study area covered Radhapuram in Tirunelveli district, Agasteeswaram and Thovalai taluks in Kanyakumari district, Tamil Nadu.The east of the KKNPP is lined up by the seashore of Gulf of Mannar and the north, west and south are bound by land (Tirunelveli district) (Table 1).The Plant Site Boundary Wall Layout of the site area is presented in Figure 1.The common habitats of terrestrial, hydrophytes and marshy vegetation are in the plains, coastal dune, shrub jungle, dry deciduous forest, ponds, tanks, rivers, canal banks, ditches, rice fields and low-lying waterlogged areas are ideal habitats for many terrestrial, aquatic, semi aquatic wetland and marsh plants.

Method
Frequent field surveys were carried out in about 30 radius of Kudankulam Nuclear Power Project during September 2012 to August 2013.Diversity of each species and their distribution in Gulf The endemic and rare status of plant was determined using the published flora of Daniel and Umamaeswari (2001).The entire specimen was cross checked from Sri Paramakalyani Centre for Excellence in Environmental Science herbarium, Alwarkuruchi, Tamil Nadu (India).

RESULTS AND DISCUSSION
Euphorbiaceae is the third largest family with 32 species of plants belonging to 12 genera and considered as one of the best represented families of about 30 km radius of Kudankulam Nuclear Power Project area.
The earliest floristic exploration of the Tirunelveli and Kanyakumari region floras was undertaken in the last century (Beddome, 1877;Lawson, 1894).Most of the existing studies in the Agastyamalai region pertain to the floristic enumerations from the Kanniyakumari, Tirunelveli (Lawrence, 1959;1960;Nayar, 1959;Sankaranarayanan, 1960;Subramanyam and Henry, 1973;Sharma et al., 1973;Rao et al., 1975).Vanila (2003) collected 793 species from 416 genera belonging to 102 families.Uthayakumari Kalavathy (2004) recorded 412 species of monocotyledons belonging to 185 genera and 26 families from Tirunelveli hills.But, Jothi (2001) described the Euphorbiaceae floristic enumerations from the Tirunelveli hills and also intraspecific variation in some species of Euphorbiaceae from Tirunelveli hills (Jothi and Manickam, 2005).Ayyanar and Ignacimuthu (2010) studied diversity, conservation status and medicinal plants of the family euphorbiaceae in Tirunelveli Hills.Jatropha maheswarii Subr.& Nayar is found in Gulf of Mannar Biosphere Reserve and identified as strict endemic plants (Daniel and Umamaeswari, 2001).

Conclusion
KKNPP area has great diversity of plants with varied economic importance and most of the species are locally threatened (Table 1).Sand quarrying in major parts of the coastal dune area has resulted in geomorphological changes only to the disadvantage of the people around there.This has become a social problem leading to clash between communities in the mainland coast where there is sand mining for quartz.Some of the threats like heavy influence of plain land converted for housing development, construction activities adversely affected the existing ecosystem.J. maheswarii Subr.& Nayar is one of the important medicinal floras.This species should be conservation need.

Figure 1 .
Figure 1.Location map of about 30 km radius of Kudankulam Nuclear Power Project area in Tamil Nadu, southern India.

Table 1 .
Diversity status of Euphorbiaceous plants in KKNPP site.