An evaluation of coastal sand dune flora of Cuddalore District, Tamil Nadu, India: perspectives for conservation and management

Figures & data

Figure 1. The geographical location of the study area.

Figure 2. Contribution of plant species from families of the coastal sand dune.

Figure 3. Percentage of coastal sand dune species representing different habit types.

Table 1. The list of sand dune flora under different zones from Cuddalore coast.

					Beach berm/Incipient Dune	Fore Dune	Hind Dune
Species	Family	Habit	Native/Exotic	Annuals/Perennials	0–20 m	21–60 m	61–120 m
Abrus precatorius L.	Fabaceae	Climber	N	P			*
Achyranthes aspera L.	Amaranthaceae	Herb	N	A		*
Aeschynomene aspera L.	Fabaceae	Herb	N	A			*
Almania nodiflora (L.) R. Br. ex Wight.	Amaranthaceae	Herb	N	A		*	*
Alysicarpus monilifer (L.) DC.	Fabaceae	Herb	N	A	*	*	*
Anacardium occidentale L.	Anacardiaceae	Tree	E	P			*
Asparagus racemosus Willd.	Asparagaceae	Climber	N	P			*
Axonocarpus compressus (Sw.) P.Beauv.	Poaceae	Herb	N	A			*
Azadirachta indica A. Juss.	Meliaceae	Tree	N	P		*	*
Blumea eriantha DC.	Asteraceae	Herb	N	A			*
Boerhavia diffusa L.	Nyctaginaceae	Herb	N	P		*	*
Borassus flabellifer L.	Arecaceae	Tree	N	P		*	*
Brachiaria distachya (L.) Stapf	Poaceae	Herb	N	A		*	*
Brachiaria reptans (L.) C.A.Gardner & C.E.Hubb.	Poaceae	Herb	N	A			*
Bulbostylis barbata (Rottb.) C.B.Clarke	Cyperaceae	Herb	N	A		*	*
Caesalpinia bonduc (L.)Roxb.	Fabaceae	Climber	N	P		*
Calophyllum inophyllum L.	Calophyllaceae	Tree	N	P			*
Calotropes gigantea (L.) R.Br.	Apocynaceae	Shrub	N	P			*
Canavalia rosea (Sw.) DC.	Fabaceae	Climber	N	P	*	*
Capparis zeylanica L.	Capparaceae	Climber	N	P			*
Casuarina equisetifolia L.	Casuarinaceae	Tree	N	P		*	*
Citrullus colocynthis (L.) Schrad.	Cucurbitaceae	Climber	N	A			*
Cleome felina L.f.	Cleomaceae	Herb	N	A			*
Cleome viscosa L.	Cleomaceae	Herb	N	A		*
Coccinea grandis (L.) Voigt	Cucurbitaceae	Climber	N	P			*
Cocos nucifera L.	Arecaceae	Tree	E	P			*
Crotalaria pallida pallida	Fabaceae	Herb	N	A			*
Croton bonplandianus Baill.	Euphorbiaceae	Herb	E	A			*
Cynodon dactylon (L.) pers.	Poaceae	Herb	N	P			*
Cyanotis axillaris (L.) D.Don ex Sweet	Commelinaceae	Herb	N	A			*
Cyperus arenarius Retz.	Cyperaceae	Herb	N	A	*	*	*
Cyperus castaneus Willd.	Cyperaceae	Herb	N	A			*
Cyperus compressus L.	Cyperaceae	Herb	N	A			*
Cyperus pygmaeus Rottb.	Cyperaceae	Herb	N	A	*
Cyperus rotundus L.	Cyperaceae	Herb	N	A			*
Cyperus stoloniferus Retz.	Cyperaceae	Herb	N	A	*
Dactyloptenium aegypticum (L.) Willd.	Poaceae	Herb	E	A	*	*	*
Desmodium biarticulatum (L.)F.Muell.	Fabaceae	Herb	N	P			*
Desmodium triflorum (L.) DC.	Fabaceae	Herb	N	P	*	*	*
Dolichos trilobus L.	Fabaceae	Climber	N	P			*
Eleocharis atropurpurea (Retz.) J.Presl & C.Presl	Cyperaceae	Herb	N	A			*
Eragrostis plumosa (Retz.) Link.	Poaceae	Herb	N	A			*
Eragrostis tenella (Linn.) P Beauv.	Poaceae	Herb	N	A			*
Eragrostis viscosa (Retz.) Trin.	Poaceae	Herb	N	A	*	*	*
Euphorbia rosea Retz.	Euphorbiaceae	Herb	N	A	*	*	*
Ficus amplissima Sm.	Moraceae	Tree	N	P			*
Fimbristylis cymosa R.Br.	Cyperaceae	Herb	N	A	*		*
Fimbristylis falcata (Vahl) Kunth	Cyperaceae	Herb	N	P			*
Fluggea leucopyrus Willd.	Phyllanthaceae	Shrub	N	P			*
Garcinia spicata (Wight & Arn.) Hook.f.	Clusiaceae	Tree	N	P			*
Ocimum tenuiflorum L.	Lamiaceae	Herb	N	P			*
Gisekia pharnaceoides L.	Molluginaceae	Herb	N	A		*	*
Glinus oppositifolius (L.) Aug. DC.	Molluginaceae	Herb	N	A			*
Gloriosa superba L.	Colchicaceae	Climber	N	A			*
Gmelina asiatica L.	Lamiaceae	Shrub	N	P			*
Gomphrena celosioides Mart.	Amaranthaceae	Herb	N	A			*
Hedyotis graminifolia L.f.	Rubiaceae	Herb	N	P		*	*
Hedyotis herbacea L.	Rubiaceae	Herb	N	A			*
Hibiscus ovalifolius (Forssk.) Vahl.	Malvaceae	Shrub	N	A			*
Ipomoea pes-caprae (L.) R.Br.	Convolvulaceae	Herb	N	P	*	*	*
Ipomoea pes-trigridis L.	Convolvulaceae	Herb	N	A			*
Lannea coromandelica (Houtt.) Merr.	Anacardiaceae	Tree	N	P			*
Launaea sarmentosa (Willd.)	Asteraceae	Herb	N	A	*	*	*
Limnophila indica (L.) Druce	Scrophulariaceae	Herb	N	A			*
Lindernia crustacea (L.) F.Muell	Linderniaceae	Herb	N	A			*
Ludwigia perennis L.	Onagraceae	Herb	N	A			*
Mollugo disticha (L.) Ser.	Molluginaceae	Herb	N	A		*
Mollugo nudicaulis Lam.	Molluginaceae	Herb	N	A			*
Mollugo oppositifolia L.	Molluginaceae	Herb	N	A			*
Murdannia spirata (L.) G.Brückn	Commelinaceae	Herb	N	A	*		*
Oldenlandia corymbosa L.	Rubiaceae	Herb	N	A	*	*	*
Oldenlandia umbellata L.	Rubiaceae	Herb	N	A	*	*	*
Panicum repens L.	Poaceae	Herb	N	A			*
Panicum sp	Poaceae	Herb	N	A			*
Paspalidium scrobiculatum L.	Poaceae	Herb	N	P			*
Pedalium murex Linn.	Pedaliaceae	Herb	N	A		*	*
Perotis indica (L.) Kuntze	Poaceae	Herb	N	A		*	*
Phoenix pusilla Gaertn.	Arecaceae	Shrub	N	P			*
Phyla nodiflora (L.) Greene.	Verbenaceae	Herb	N	A			*
Phyllanthus amarus Schum. & Thonn.	Phyllanthaceae	Herb	N	A		*	*
Phyllanthus virgatus G.Forst.	Phyllanthaceae	Herb	N	A			*
Phyllanthus reticulatus Poir.	Phyllanthaceae	Shrub	N	P			*
Polycarpaea corymbosa (L.) Lam.	Caryophyllaceae	Herb	N	A			*
Polygala arvensis Willd.	Polygalaceae	Herb	N	A			*
Portulaca tuberosa Roxb.	Portulacaceae	Herb	N	A			*
Prosopis juliflora (Sw.) DC.	Fabaceae	Tree	E	P		*
Rivea hypocrateriformis (Desr.) Choisy	Convolvulaceae	Climber	N	P			*
Scoparia dulcis L.	Plantaginaceae	Herb	N	P		*	*
Senna occidentalis (L.) Link.	Fabaceae	Tree	N	A
Sida cordiflolia L.	Malvaceae	Herb	N	A		*	*
Spermacoce articularis L.f.	Rubiaceae	Herb	N	P	*	*	*
Spermacoce hispida L.	Rubiaceae	Herb	N	P	*	*	*
Spinifex littoralis (Burm.f.) Merr.	Poaceae	Herb	N	P	*	*	*
Syzygium cumini (L.) Skeels	Myrtaceae	Tree	N	P			*
Tephrosia villosa (L.) Pers.	Fabaceae	Herb	N	A			*
Thespesia populnea (L.) Sol. Ex Correa.	Malvaceae	Tree	N	P			*
Tiliacora acuminata (Lam.) Hook. f. & Thoms.	Menispermaceae	Climber	N	P			*
Tinospora cordifolia (Willd.) Hook. f.	Menispermaceae	Climber	N	P			*
Trachys muricata (L.) Pers. ex Trin.	Poaceae	Herb	N	A		*	*
Tylophora indica (Burm. f.) merr.	Apocynaceae	Climber	N	P			*
Vernonia cinerea (L.) Less.	Asteraceae	Herb	N	A		*	*
Waltheria indica L.	Malvaceae	Herb	N	P			*
Wattakaka volubilis (Lf) Stapf.	Apocynaceae	Climber	N	P			*
Ziziphus oenoplia (L.) Miller	Rhamnaceae	Climber	N	P			*
Zornia diphylla (L.) Pers.	Fabaceae	Herb	N	A			*

N-native; E-Exotic; A-Annual; P-Perennial; *-Presence.

Table 2. Diversity indices values of the study sites.

Sl. No.	SITE	SHANON’S INDEX (H)	SIMPSON’S INDEX (D)	Hmax	Evenness J = H/Hmax
1	IL&FS*	2.52	0.89	3.05	0.82
2	Samiyar pettai**	2.37	0.88	2.77	0.85
3	TS Pettai***	2.14	0.85	2.56	0.83
4	Ashley’s Broken Bridge*	2.28	0.88	2.56	0.89
5	Kayalpattu**	1.96	0.84	2.19	0.89
6	Rasapettai***	2.17	0.87	2.48	0.87

*Highly disturbed **Moderately disturbed ***Slightly disturbed

Figure 4. Plant species contributing to the similarity in Bray-Curtis clusters.

Figure 5. Changes of sand dune distribution between 2003 to 2020: (a) sand dune distribution in 2003 (b) in 2020 and (c) changes between 2003–2020.

Figure 6. A schematic diagram representing coastal sand dune flora: (a) Present scenario depicting a mixed species disposition of vegetation (b) Species proposed as structured biozone so as to enhance conservation efforts.