Chasmophytic grasses of Velliangiri Hills in the southern Western Ghats of Tamil Nadu, India

Binu Thomas ¹, A. Rajendran ², K. Althaf Ahamed Kabeer ³ & R. Sivalingam ⁴

^1,2,4 Department of Botany, School of Life Sciences, Bharathiar University, Coimbatore, Tamil Nadu 641046, India

³ Botanical Survey of India, Southern Circle, Coimbatore, Tamil Nadu 641003, India

Email: ¹binuthomasct@gmail.com, ² drarajendra@gmail.com,

³ althafgrass@gmail.com,⁴ drsivar@gmail.com (corresponding author)

Date of publication (online): 26 December 2012

Date of publication (print): 26 December 2012

ISSN 0974-7907 (online) | 0974-7893 (print)

Editor: N.P. Balakrishnan

Manuscript details:

Ms # o3107

Received 21 February 2012

Final received 14 October 2012

Finally accepted 29 October 2012

Citation: Thomas, B., A. Rajendran, K.A.A. Kabeer & R. Sivalingam (2012). Chasmophytic grasses of Velliangiri Hills in the southern Western Ghats of Tamil Nadu, India. Journal of Threatened Taxa 4(15): 3462–3472.

Copyright: © Binu Thomas, A. Rajendran,K. Althaf Ahamed Kabeer & R. Sivalingam 2012. Creative Commons Attribution 3.0 Unported License. JoTT allows unrestricted use of this article in any medium for non-profit purposes, reproduction and distribution by providing adequate credit to the authors and the source of publication.

Acknowledgements: We are all thankful to Professor and Head, Department of Botany, Bharathiar University, Coimbatore and Head of Office, Botanical Survey of India, Southern Circle, Coimbatore for providing necessary facilities to carry out the present research.

The publication of this article is supported by the Critical Ecosystem Partnership Fund (CEPF), a joint initiative of l’Agence Françaisede Développement, Conservation International, the European Commission, the Global Environment Facility, the Government of Japan, the MacArthur Foundation and the World Bank.

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Rock crevices play a key role in forming a major habitat for many plants, and host rich biodiversity within a small area. The rocky habitat provides extremely harsh physical environment for plants that leads to the development of specialized plant communities with endemic and habitat specific species. The microhabitat like rock crevices possessdiverse forms of plants, which are mainly seasonal herbs. These habitats differ from each other due to changes in geographical terrain and soil cover (Porembski2000).

Chasmophytes are plants rooted in clefts of rocks that are filled with detritus. In these clefts particles of earth conveyed by wind and water accumulate. The amount and rate of accumulation depend upon the width and situation of the clefts (Davis 1982). The soil thus constituted facilitates plants to establish and their dead fragments further add to the supply of the nutritive material in the clefts (Bashan et al. 2002). The chasmophyticvegetation inhabiting rock crevices and cliffs represent specific habitat with extreme ecological conditions such as extreme drought, temperature fluctuations, width of the cliffs, rate of accumulation, limited soil volume and scarce nutrients, nature of the rock types, rock hardness and sediment porosity and water holding capacity of the substratum (Nagy & Proctor 1997; Bashan et al. 2002, 2006).

The grass family occupies 23% of the land area of the world, playing a significant role in the life of human beings and animals, and has a paramount role as a food provider, accounting for more than 80% of the world’s calories (Kabeer& Nair 2009). A comprehensive account of the grasses of Tamil Nadu was published by Kabeer & Nair (2009) in their floristic studies. However, there has been no study of chasmophytic features of grasses as yet. A comprehensive study was carried out to assess the chasmophytic diversity of grasses from Velliangiri Hills of southern Western Ghats of Tamil Nadu (Fig. 1).

Study area and Methods: Velliangiri Hills are floristically rich and socio-religiously important range of southern Western Ghats situated 40km west of Coimbatore City, Tamil Nadu. The study area lies between 6⁰40’–7⁰10’E and 10⁰55’–11⁰10’N between 520–1840 m. A famous temple called ‘Velliangiri Aandavar’ temple also called “Thenkailayam” (South Kailas) is situated at the peak of the hills (1840m). The range of study area consists of seven hills with different altitudes and topography.

Correct nomenclature, habit, habitat, phenology and pattern of distribution available are given (Table 1). Plant specimens were identified with regional and local floras (Gamble & Fischer 1988; Mathew 1983; Chandrabose & Nair 1988; Henry et al. 1989; Kabeer & Nair 2009). The voucher specimens are deposited in the herbarium of Botany Department, BharathiarUniversity (BUH), Coimbatore, Tamil Nadu, India.

Results and Discussion: The data presented here are the outcome of a series of extensive and intensive studies conducted during September 2010–October 2011 had resulted in the documentation and collection of 30 species of wild chasmophytic grass taxa from VelliangiriHills of southern Western Ghats of Tamil Nadu (Images 1–35).

The present study incorporated 30 species of chasmophytic grasses distributed in 26 genera (Table 1). Among these genera Eragrostis is the dominant genus with four species, namely, aspera,tenella, nigraand uniloides. Some of the notable chasmophytic grasses are used by the local tribe ‘Malasars’. The stalks of Apluda mutica are used for making hats. Cymbopogon flexuosus is used to extract the lemon grass oil for medicinal purposes. Ash of Pogonatherum crinitum are used for skin problems. The spikeletsof Setaria palmifolia and Melinus repens are highly attractive and used ornamentally. Most of the grasses are used as fodder.

Some of the threats like heavy influence of pilgrims, recreational pressures, collection of fire wood, lack of suitable management and other construction activities adversely affect the existing ecosystem. It is suggested that the chasmophytic vegetation needs to be protected through sustainable utilization.

References

Bashan, Y., H. Vierheilig & B.G. Salazar (2006). Primary colonization and breakdown of igneous rocks by endemic succulent plants of the deserts in Baja California, Mexico. Naturwissenschaften 93: 344–347.

Bashan, Y., C.Y. Li., V.K. Lebsky & M. Monero (2002). Colonization of chasmophytic plants in arid Baja California, Mexico. Plant Biology 4: 392–402.

Chandrabose, M. & N.C. Nair (1988). Flora of Coimbatore. Botanical Survey of India, Coimbatore, 322–356pp.

Davis, P.H. (1982). Cliff vegetation in the Eastern Mediterranean. Journal of Ecology 39: 63–93.

Henry, A.N., V. Chitra & N.P. Balakrishnan(1989). Flora of Tamil Nadu. Analysis—Volume 3. Botanical Survey of India, 87–146pp.

Kabeer, K.A.A. & V.J. Nair (2009). Flora of Tamil Nadu - Grasses. Botanical Survey of India, Calcutta, 1–525pp.

Mathew, K.M. (1983). The Flora of The TamilnaduCarnatic—Volumes 1–3. The RapinatHerbarium, St. Joseph’s college, Thiruchirapalli, 1789–1915pp.

Nagy, L. & J. Proctor (1997). Soil Mg and Ni as casual factors of plant occurrence and distribution at the Meikle KilrannochUltramafic site in Scotland. New Phytology 135: 561–566.

Porembski, S. (2000). Biotic diversity of isolated rock outcrops in tropical and temperate regions. Journal of Ecology 146: 177–208.