Diversity, distribution and vegetative structure of

Diversity, distribution and vegetative structure of mangroves of the Andaman and Nicobar Islands, India P. Ragavan, Alok Saxena, P. M. Mohan, K. Ravichandran, R. S. C. Jayaraj & S. Saravanan Journal of Coastal Conservation Planning and Management ISSN 1400-0350 J Coast Conserv DOI 10.1007/s11852-015-0398-4

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Author's personal copy J Coast Conserv DOI 10.1007/s11852-015-0398-4

Diversity, distribution and vegetative structure of mangroves of the Andaman and Nicobar Islands, India P. Ragavan 1 & Alok Saxena 3 & P. M. Mohan 1 & K. Ravichandran 2 & R. S. C. Jayaraj 4 & S. Saravanan 5

Received: 27 January 2015 / Revised: 25 May 2015 / Accepted: 26 May 2015 # Springer Science+Business Media Dordrecht 2015

Abstract The present study was carried out to determine the diversity, distribution and vegetative structure of mangroves of the Andaman and Nicobar Islands (ANI). The results suggest that mangroves of the ANI consist of 38 mangrove species belonging to 12 families and 19 genera, which includes 4 hybrids and 34 species. In other words, about 50% of the global mangrove species are present in ANI. Andaman Islands have 35 species and Nicobar Islands have 21 mangrove species. The average tree density in ANI is 1746/per hectare and varies from 487 to 2383 per hectare. The Shannon diversity index for the whole ANI is 2.94 and Simpson index is 0.07. Family Rhizophoraceae constitutes an important vegetative component in the mangroves of the ANI followed by Acanthaceae, Lythraceae and Malvaceae. Rhizophora spp. constitutes 19% of the Important Value Index (IVI) and R. apiculata is dominant in ANI. Among the eight forest divisions, mangrove diversity is high in South Andaman (30 species) followed by Middle Andaman (28), Mayabunder (25),

Diglipur (25), Nicobar (21), Little Andaman (20), Havelock (20) and Baratang (20). The average mangrove plant density and Shannon diversity index (H’) is high in Middle Andaman (2101/hectare; H’ = 2.93). Species richness index (d’) is high in South Andaman (3.32). Evenness index (J’) is high in Little Andaman (0.92). Simpson dominance index (D) ranged between 0.07–0.1, and this agrees with the high diversity in mangroves of ANI. In all the divisions Rhizophora spp. constitutes a major vegetative component except, Diglipur and Nicobar. In Diglipur Bruguiera spp. are dominant, while in Nicobar Sonneratia spp. are dominant. The low similarity value of the Nicobar division with other divisions indicates the difference in floristic structure of mangroves of the Andaman Islands and Nicobar Islands. The present study also indicates that mangrove of ANI are more diverse in its species composition than the other mangrove habitats in India.

* P. Ragavan [email protected]

Introduction

1

Department of Ocean studies and Marine Biology, Pondicherry University, Brookshabad Campus, Port Blair, A & N Islands, India

2

Department of Environment and Forests, Andaman and Nicobar Administration, Port Blair, A & N Islands, India

3

Indira Gandhi National Forest Academy, Dehradun, Uttarakhand, India

4

Department of Environment and Forests, Pradesh, Arunachal, India

5

Institute of Forest genetics and Tree breeding, Coimbatore, Tamil Nadu, India

Keywords Andaman and Nicobar Islands . Diversity . Mangroves . Vegetative structure

Mangrove forests are unique plant communities of the critical interface between terrestrial, estuarine, and near-shore marine ecosystems in tropical and subtropical regions (Polidoro et al. 2010). Despite its ecological and economical values, globally mangrove areas are disappearing at the rate of about 1% per year (FAO 2003, 2007). However, little is known about the effects of either widespread or localized mangrove area loss on individual mangrove species or populations basis due to lack of species specific information. Recently (Spalding et al. 2010) recognized 73 species and hybrids as true mangroves worldwide. The past

Author's personal copy P. Ragavan et al.

and present distribution of mangroves has been reviewed by several authors on a global level (e.g. Tomlinson 1986; Ricklefs and Latham 1993; Duke 1992; Field 1995; Duke et al. 1998; Ellison et al. 1999; Saenger 2002; Wang et al. 2003). However, the exact number of mangrove flora that exists in different parts of India is not fully known due to scattered data, absence of their comprehensive compilation and lack of extensive field survey (Kathiresan 2010). According to the latest estimate by the Forest Survey of India (FSI 2013), the total mangrove area is approximately 4,628 km 2 in India, out of which, 604 km 2 occurs in Andaman and Nicobar Islands (ANI). Out of that, 601 km2 is in Andaman Islands with just 3 km2 in Nicobar Islands. Totally 13 km2 area of mangrove stands have been degraded in comparison with the 2011 assessment, as a continuing effect of the massive earthquake and subsequent tsunami of 2004 (FSI 2013). The area under mangrove cover in ANI has decreased significantly during the last decade, possibly leading to changes in floristic composition and local extinction of some species. The mangroves of ANI are probably the best in India in terms of its density and growth (Mandal and Naskar 2008; Dagar et al. 1991) but, there is no consensus on their floristic. Floristically mangroves of these islands were studied by various authors (Kloss 1902; Parkinson 1923; Sahni 1958; Chapman 1976c, 1977a, b; Thothathri 1981; Dagar 1982; Singh and Garge 1993; Dagar and Dagar 1986; Mall et al. 1985; Rao and Chakraborti 1987; Mall et al. 1987; Singh et al. 1987a; Ellis 1987; Dagar et al. 1991; Jagtap 1992; Sreekumar and Kala 1998; Hajra et al. 1999; Sinha 1999; Dagar and Singh 1999; Singh 2003; Debnath 2004; Sampath Kumar 2005; Damroy et al. 2009; Ragavan et al. 2014a, Goutham Bharathi et al. 2014), but little is known on the vegetation structure and the spatial patterns of mangroves of the ANI and information is almost restricted to a few sites (e.g. Mall et al. 1982; Dagar 1982; Singh et al. 1986; Singh et al. 1987b; Dagar and Sharma 1989; Damroy 1995a, b; Mall et al. 1991; Singh and Garge 1993). Moreover, in the recent past, after 26th December 2004 earthquake and tsunami, no systematic and field based efforts have been taken to assess the changes in diversity and vegetative structure of mangroves of ANI, except some new distributional records (Damroy et al. 2009; Nehru and Balasubramanian 2012; GouthamBharathi et al. 2012; Ragavan et al. 2014b, 2015) and post tsunami status assessment in three sites of the Andaman islands by Das et al. (2014). Recently Goutham-Bharathi et al. (2014) reported 25 mangrove species based on superficial survey and intensive literature review. The Zonation of mangrove forests in relation to biotic and abiotic factors such as salinity fluctuations, sediment parameters and inundation regimes have been studied by various authors (Watson 1928; van Steenis 1957; Chapman 1976a, b, 1977a, b; Bunt and Williams 1981; White et al. 1989; Aragones et al. 1998). According to

Smith (1992) Mangroves in the Indo-Pacific region often show a typical zonation pattern along the tidal gradient with Aegiceras, Avicennia and Sonneratia in the lower intertidal zone, Bruguiera and Rhizophora in the midintertidal zone and other species such as Xylocarpus and Heritiera in the higher intertidal region. Yet, this cannot be generalized and other studies revealed that zonation patterns might be different and very complex in an area rich in variety and strong freshwater influences (Macnae 1966; Bunt and Bunt 1999; Bunt and Stieglitz 1999; Bunt et al. 1991; Bunt 1996; Ellison et al. 2000; Ellison and Fransworth 2001; Upadhyay et al. 2007; Hinrichs et al. 2009). In India zonation in mangroves has been studied by several authors (Utawale et al. 1973; Rao and Sastry 1972; Blasco 1977; Singh et al. 1986; Upadhyay et al. 2007). In ANI Dagar et al. (1991) and Singh and Garge (1993) briefly recognized the occurrence of mangrove species in three zones i.e., Proximal, Middle and Distal zone. In the recent past zonation pattern in the mangroves of the ANI has not been traced. Exclusive quantitative studies on mangrove zonation carried out by Bunt and Bunt (1999); Bunt and Stieglitz (1999); Ellison et al. (2000) and Upadhyay et al. (2007) shows that interspecific competition or propagule dispersal may be more important than edaphic variables in controlling the size and relative abundance of co-occurring species, since mangrove species vary in their tolerance to underlying edaphic gradients and considerable overlap among the species occurs, making discrete zones difficult to identify (Ellision and Fransworth 2001). Thus, in this study zonation pattern was assessed based on our field observation on variation in species composition with respect to proximity to sea. The present survey was done to analyze various ecological attributes and find out the changes in the mangrove vegetation in ANI. The findings will help forest department in producing plans for long-term forest sustenance, community livelihood and mitigation of cyclonic impacts.

Fig. 1 Map showing the study sites in Andaman and Nicobar Islands South Andaman (1) Chediyatapu (2) Burmanallah (3).Bedonabad (4) Carbyn cove (5) Sippighat (6) Manjeri (7) Guptapara (8) Manglutan (9)Wandoor (10)Ograbranch (11) Bambooflat creek (12) Wright myo creek (13)Shoalbay creek (14)Jirkatang (15)Trirur; Baratang (16) Middle starit (17) Weafter creek (18) Baludera; Middle Andaman (19) Kadamtala creek (20) Yerrata creek (21)Shyamkund creek (22) Dhaninallah creek (23) Rangat Bay (24) Panchwati; Mayabunder (25) Austin creek (26) Mohanpur creek (27) Karmatang creek (28) Chainpur creek (29) Rampur (30) Danapur (31)Tugapur; Diglipur (32) Parangara creek (33) Kishorinagar creek (34)Kalighat creek (35) Smith Island (36)Areal bay (37) Radha Nagar (38) Lakshmipur (39) Durgapur, (40) Ram nagar; Havelock (41) Govind Nagar (42) Radha nagar (43) Neil Island; Little Andaman (44) V.K Pur creek (45) Dugong creek (46) Jackson creek; Nicobar islands (47) Carnicobar (48) Kamorta (49) katchal (50) cambpell bay (51) Trinket Island

Author's personal copy Diversity, Distribution and Vegetative structure of mangroves of the Andaman and Nicobar Islands, India

37 38

35 36 39

33 25

40 34 32

26 30 29 27

31 28

24 23 20

22 21

19 18

12 17

41 42

12 13

11

11 10

11 9 8 7 6

47

43 4 5 3 2 1

48 51 49

46

45 44 50


Materials and methods Data collection methods A survey was carried out at 51 sites in 8 forest divisions of the ANI between 2009 and 2013 (Fig. 1). In this study line transects (150 m) were laid perpendicular to the water front in both the directions i.e. from seaward edge of mangrove toward land and from the landward edge to the waterfront in equal numbers at minimum 50 m interval between adjacent transects (Fig. 2).Quantitative data on mangrove vegetative structure was collected by laying quadrats (10 × 10 m) along the line transects. In each line transect four quadrats were laid at 0, 50, 100 and 150 m. Altogether 1310 quadrats were sampled, i.e., 13.10 ha area. All individuals of the trees with a circumference > 7 cm at breast height (DBH = 2.50 cm) were counted species wise in each quadrat. In case of homogenous patches of the Acrostichum and Acanthus species quadrats of 2 m × 2 m were laid and individuals within the plots were counted. Plant collections were made of all the mangrove species encountered from the range of sites visited. For each species, both numeric and multistate attributes of a

Fig. 2 Sampling design

wide range of vegetative and reproductive morphological characters were observed from one or two individuals at each site. All measurements and observations were made from fresh material. As many as 2–5 specimens for each species were sampled, each sample having flowers and fruits, and grouped according to the morphological characters. The plants were packed separately in polythene bags and brought to lab for analyzing taxonomically with prior assessments (Duke and Bunt 1979; Tomlinson 1986; Duke and Jackes 1987; Banerjee et al. 1989; Duke 1991, 2006a; Kathiresan 2002; Kathiresan 2000; Debnath 2004; Dagar et al. 1991; Giesen et al. 2006). All sites have been visited at least once at the time of flowering of the different species to crosscheck identification with flower-based diagnostic features. Herbarium specimens were prepared and stored at the Botanical Survey of India, Regional Centre in Port Blair. Species nomenclature primarily followed Tomlinson (1986), and the family nomenclature primarily followed Stevens (2001), with the exception of Pteridaceae. Nomenclature of the identified species was also checked with the International Plant Naming Index (IPNI).


Data analysis From the count data abundance, density and frequency and their relative values and Importance Value Index (IVI) was calculated by applying the principles of Curtis and Mclntosh (1950); Misra (1968) and MullerDombois and Ellenberg (1974). The abundance and density represent the numerical strength of species in the community (Misra 1968). Abundance is the number of individuals of any species per sampling units of occurrence and density represents the numerical strength of a species in a community. The number of individuals in the species in any unit area is its density, which gives an idea of degree of competition. Frequency is the number of sampling units in percent, in which a particular species occur. The IVI is calculated to determine the species composition of the mangrove forest and species dominance. The concept of ‘Importance Value Index (IVI)’ has been developed for expressing the dominance and ecological success of any species, with a single value (Misra 1968). This index utilizes three characteristics viz., Relative frequency, relative density and relative abundance/dominance. Relative abundance/dominance can be calculated by the number of individual, girth size or basal area (Dash and Dash 2009). In this study relative abundance was calculated based on number of individuals. Apart from this, univariate measures viz., Shannon-Wiener diversity index (H′) (Shannon and Weiner 1963), Margalef ’s species richness (d) (Margalef 1978), Pielou’s evenness (J′) (Pielou 1966) and Simpson dominance (D) (Simpson 1949) were analyzed using Microsoft Excel 2007. In this work, we have assessed zonation pattern based on our extensive field survey and observation with reference to the five zone system recognized by Watson (1928), van Steenis (1958), Chapman (1975) and Aksornkoae (1993). Plant density and species composition was applied to describe the community structure by hierarchical clustering (BrayCurtis similarity) using PRIMER v. 6 software (Clarke and Gorley 2006).

Ceriops decandra, Kandelia candel and Sonneratia apetala) were not recorded in this study and 6 species viz., Excoecaria indica, Rhizophora x annamalayana, Sonneratia ovata, Sonneratia lanceolata, Sonneratia x urama and Sonneratia x gulngai were recorded from ANI for the first time. The average tree density in ANI is 1746 per hectare and varied from 487 to 2383 per hectare. The Shannon diversity index for the whole ANI is 2.94 and Simpson index is 0.07 (Table 2), which indicates the significantly higher diversity in the mangroves of ANI. Family Rhizophoraceae is an important constituent of the vegetative structure in the mangroves of ANI followed by Acanthaceae, Lythraceae and Malvaceae. Rhizophora spp. constitutes 19% of the IVI followed by Bruguiera spp. (16%), Sonneratia spp. (9%), Acanthus spp. (8%), Xylocarpus spp. (6%) and Avicennia spp. (6%) (Fig. 3). IVI for Rhizophora apiculata is the highest in ANI followed by Bruguiera gymnorrhiza, Ceriops tagal, Rhizophora mucronata, Bruguiera cylindrica and Xylocarpus granatum (Table 3). Site wise density and diversity indices are given in Table 4. Site wise species distribution with their density and IVI are given in Annexure1. Among the 51 sites surveyed density is highest in the Dhaninallah creek (2383/hectare) and lowest at Katchal (487/hectare); the Shannon diversity index ranged between 2.82 and 1.76. Except Sonneratia lanceolata, Sonneratia x urama and Sonneratia x gulngai all the other 35 mangrove species are found in Andaman Islands, with Sonneratia caseolaris recorded only in Little Andaman in the Andaman group. In Andaman Islands the average tree density is 1818/hectare. The dominant species in Andaman Islands is Rhizophora apiculata followed by Bruguiera gymnorrhiza, Ceriops tagal, Rhizophora mucronata, Bruguiera cylindrica, Excoecaria agallocha and Xylocarpus granatum. In Andaman Islands Rhizophora spp. constitute 19% of the IVI followed by Bruguiera spp. (Fig. 4). A significantly higher Shannon diversity was found in the Andaman Islands (2.91). Spatial variation among the divisions

Results A total of 38 mangrove species from 12 families and 19 genera were identified from ANI (Table 1). In other words, approximately 50% of the total numbers of global mangrove species are present in ANI. In contrast to earlier reports 7 species (Avicennia alba, Aglaia cucullata, Bruguiera sexangula, Aegialitis rotundifolia,

Among the 8 forest divisions maximum number of species were identified from South Andaman (30 species) followed by Middle Andaman (28), Mayabunder (25), Diglipur (25), Nicobar (21), Little Andaman (20), Havelock (20) and Baratang (20). The average mangrove plant density and Shannon diversity index are high in Middle Andaman. The species richness index is higher in South Andaman. Evenness index is high in

Author's personal copy P. Ragavan et al. Table 1

Distribution of mangrove species in ANI (+ indicates presence; − indicates absences)

Family

Genus

Species

SA

BR

MA

MB

DG

LT

HL

NC

Herbarium A. No.

Acanthaceae

Acanthus

Acanthus ebracteatus Acanthus ilicifolius Acanthus volubilis Avicennia marina Avicennia officinalis Acrostichum aureum Acrostichum speciosum Aegiceras corniculatum Bruguiera cylindrica Bruguiera gymnorrhiza Bruguiera parviflora Ceriops tagal Rhizophora apiculata Rhizophora mucronata Rhizophora stylosa Rhizophora x annamalayana Rhizophora x lamarckii

+ + + + + + + + + + + + + + + +

− + − + + + − − + + + + + + − −

− + − + + + − + + + + + + + − +

− + − + + + − + + + + + + + − +

− + − + + + − + + + + + + + − −

− + − + + + − − + + + + + + − −

− + − + − + − − + + − + + + + +

− + − − − + − − + − + + + + +

30969, 30970 30965,30966 30967, 30968 30997,30998 31011,31012 31005,31006 30931,30932 30929,30930 30945,30946 30951,30952 30947,30948 30949,30950 30989,30990 30955,30956 30953,30954 30943,30944

+

−

−

−

−

−

+

−

31007,31008

Cynometra iripa Dolichondrone spathaceae Excoecaria agallocha Excoecaria indica Lumnitzera littorea Lumnitzera racemosa Nypa fruticans Phoenix paludosa Scyphyphora hydrophyllacae Pemphis acidula Sonneratia alba Sonneratia caseolaris Sonneratia griffithii

+ + + − + + + + + + + − −

+ + + − + − − + + − + − −

+ + + + + + + + + − + − +

+ + + − + + + + + + + − −

+ + + − + − + + + + + − +

+ + + − − − + + − − + + +

− + + − + − − − + + + − −

− + + + + + + − − − + + −

30939,30940 30995,30996 30935,30936 30937,30938 30981,30982 30983,30984 31015,31016 31003,31004 30971,30972 30975,30976 30999,31000 30924, 30925 30963,30964

Sonneratia x gulngai Sonneratia lanceolata Sonneratia ovata Sonneratia x urama Brownlowia tersa Heritiera littoralis

− − + − − +

− − − − − +

− − + − + +

− − − − − +

− − − − + +

− − − − − +

− − + − − +

+ + + + − +

30927 30922,30923 30961,30962 30926 30987,30988 30985,30986

Xylocarpus granatum Xylocarpus moluccensis Total no. species Total no. genus Total no. family

+ − 30 18 12

+ + 20 16 10

+ + 28 18 12

+ + 25 18 12

+ + 25 18 12

+ − 20 14 9

+ − 20 14 9

− − 21 11 9

31013,31014 30993,30994

Avicennia Pteridaceae

Acrostichum

Myrsinaceae Rhizophoraceae

Aegiceras Bruguiera

Ceriops Rhizophora

Fabaeae Bignoniaceae Euphorbiaceae

Cynometra Dolichondrone Excoecaria

Combretaceae

Lumnitzera

Arecaceae

Nypa Phoenix Scyphiphora Pemphis Sonneratia

Rubiaceae Lythraceae

Malvaceae

Brownlowia Heritiera Xylocarpus

SA South Andaman, BR Baratang, MA Middle Andaman, MB Mayabunder, DG Diglipur, LT Little Andaman, HL Havelock, NC Nicobar

Little Andaman. Simpson index ranged between 0.07– 0.1, and this indicates the high diversity in the mangroves of ANI. IVI for the different species differed among the divisions. In all the division, except

Nicobar, IVI is the maximum for R. apiculata while in Nicobar IVI for R. mucronata is high (Table 3). IVI for R. apiculata is the highest in Havelock Island (48.66).

Author's personal copy Diversity, Distribution and Vegetative structure of mangroves of the Andaman and Nicobar Islands, India Table 2

Division wise density, diversity and univariate measures

Divison

Density/hectare

No of species recorded

Shannon-Wiener Index (H’)

Margalef’s species richness (d)

Pielou’s evenness (J′)

Simpson dominance (D)

South Andaman Baratang Middle Andaman Mayabunder

1649 1784 2101 1980

30 20 28 25

2.86 2.58 2.93 2.83

3.32 2.57 3.28 2.85

0.84 0.86 0.88 0.87

0.08 0.10 0.07 0.07

Diglipur Little Andaman Havelock Nicobar Andaman Islands ANI

1965 1962 906 772 1818 1746

25 20 20 21 35 38

2.78 2.76 2.59 2.59 2.91 2.94

2.87 2.64 3.13 3.05 3.39 3.68

0.86 0.92 0.87 0.85 1 0.81

0.07 0.07 0.10 0.10 0.07 0.07

South Andaman In South Andaman totally 30 species belonging to 18 genera and 12 families were identified (Table 1). The average tree density is 1649 per hectare. The Shannon diversity index is 2.86 and Simpson dominance is 0.08 (Table 2). R. apiculata is the dominant species in South Andaman followed by Bruguiera gymnorrhiza, Acanthus ebracteatus, Ceriops tagal, Excoecaria agallocha,

Fig. 3 Species composition in ANI based on IVI percentage

Bruguiera cylindrica and Xylocarpus granatum (Table 3). Rhizophora spp. constitutes 18% of IVI followed by Bruguiera spp. (17%), Acanthus spp. (12%) and Ceriops spp. (6%). Among the fifteen sites surveyed in South Andaman maximum number species were recorded from Shoal Bay creek (24 species) and species richness was also high. Density and the Shannon diversity index is higher in Jirkatang (Table 4). IVI for Rhizophora apiculata is high at all

5.54

63.32

10.55

35.62

85.22

34.83

0

106.07

193.93

63.06

128.76

3.96

24.54

101.32

0

24.54

34.3

3.96

25.07

1.06

11.61

297.36

76.78

14.51

1.58

0.53

67.02

60.69

0

0

0

0

25.07

0

103.43

0

1649.34

Acanthus volubilis

Acrostichum aureum

Acrostichum speciosum

Aegiceras corniculatum

Avicennia marina

Avicennia officinalis

Brownlowia tersa

Bruguiera cylindrica

Bruguiera gymnorrhiza

Bruguiera parviflora

Ceriops tagal

Cynometra iripa

Dolichondrone spathaceae

Excoecaria agallocha

Excoecaria indica

Heritiera littoralis

Lumnitzera littorea

Lumnitzera racemosa

Nypa fruticans

Pemphis acidula

Phoenix paludosa

Rhizophora apiculata

Rhizophora mucronata

Rhizophora stylosa

Rhizophora x annamalayana

Rhizophora x lamarckii

Scyphiphora hydrophyllaceae

Sonneratia alba

Sonneratia caseolaris

Sonneratia griffithii

Sonneratia gulngai

Sonneratia lanceolata

Sonneratia ovata

Sonneratia urama

Xylocarpus granatum

Xylocarpus moluccensis

Total

0

16.36

0

6.62

0

0

0

0

10.13

11.55

1.1

2.19

4.15

13.4

35.39

4.85

4.03

7.52

4.1

6.94

5.6

0

15.41

5.73

2.97

19.3

10.62

25.93

16.38

0

7

13.13

7.3

6.56

11

7.34

8.01

9.39

1784.44

18.88

92.22

0

0

0

0

0

0

82.22

60

0

0

0

166.67

384.44

32.22

0

0

0

82.22

8.89

0

85.56

17.78

17.78

158.89

34.44

246.67

134.44

0

17.78

36.67

0

0

66.67

0

40

0

5.46

15.77

0

0

0

0

0

0

14.13

12.01

0

0

0

22.36

43.26

10.24

0

0

0

15.02

4.53

0

14.91

6.13

6.93

24.94

8.57

32.26

19.42

0

8.4

9.55

0

0

14.97

0

11.14

0

IVI

2101.11

31.67

112.22

0

0.56

0

0

37.76

0

75.56

63.89

0

14.44

0

117.22

377.78

44.44

0

20.56

27.22

93.89

20.56

18.89

113.33

46.67

18.89

191.67

39.44

173.33

118.89

13.33

76.67

120.56

23.33

0

62.78

0

45.56

0

Den/ha

MA

6

15.31

0

0.94

0

0

6.79

0

10.27

9.13

0

6.39

0

15.22

34.97

7.52

0

7.51

14.92

11.89

4.44

4.87

14.05

7.45

4.51

21.08

6.66

21.83

14.45

7.46

10.32

14.12

4.83

0

9.72

0

7.35

0

IVI

1980.26

13.16

122.34

0

0

0

0

0

0

70.61

95.18

0

14.04

0

118.86

299.12

27.63

2.19

1.32

20.18

102.63

12.28

0

107.02

17.11

19.74

166.67

55.7

217.11

155.26

0

64.91

91.23

35.09

0

96.49

0

54.39

0

Den/ha

MB

3.8

17.14

0

0

0

0

0

0

11.39

13.33

0

6.39

0

16.76

32.51

7.15

5.07

3.07

12.55

14.19

4.67

0

14.7

5.46

5

20.2

9.09

26.21

19.06

0

10.04

12.65

7.53

0

13.11

0

8.93

0

IVI

1965.28

8.8

118.52

0

0

0

0

20.36

0

41.67

32.41

0

0

0

191.2

285.65

37.04

0.93

0.93

0

16.2

28.7

0

101.85

36.11

31.02

165.74

61.11

236.57

156.02

5.56

82.41

81.02

19.44

0

125.46

0

80.56

0

Den/ha

DG

3.27

17.09

0

0

0

0

6.34

0

8.17

6.94

0

0

0

23.1

31.44

10.63

3.01

3.01

0

7.7

6.71

0

14.81

7.62

7.03

20.73

10.38

27.39

19.56

4.89

12.8

12.58

5.22

0

17.09

0

12.48

0

IVI

906.25

0

16.67

0

12.5

0

0

0

0

39.58

33.33

45.83

20.83

75

122.92

214.58

0

16.67

0

0

70.83

43.75

0

12.5

6.25

0

60.42

0

41.67

20.83

0

0

6.25

0

0

29.17

0

16.67

0

Den/ha

HL

0

0

7.22

0

11.81

0

0

0

0

14.23

11.78

13.76

8.8

22.78

29.4

48.66

0

9.48

0

0

28.09

15.68

0

7.37

4.2

0

16.8

0

16.18

9.36

0

0

6.16

0

0

10.44

0

7.8

0

IVI

SA South Andaman, BR Baratang, MA Middle Andaman, MB Mayabunder, DG Diglipur, LT Little Andaman, HL Havelock, NC Nicobar

7.12

37.99

Acanthus ebracteatus

Den/ha

Den/ha

IVI

BR

SA

Species wise density and IVI in eight forest divisions of the ANI

Acanthus ilicifolius

Species

Table 3

1962.69

0

135.82

0

0

0

0

1.49

83.58

65.67

0

0

0

0

83.58

319.4

77.61

0

98.51

0

0

58.21

0

95.52

41.79

47.76

201.49

43.28

220.9

110.45

0

47.76

92.54

0

0

95.52

0

41.79

0

Den/ha

LA

0

21.3

0

0

0

0

1.55

12.98

11.24

0

0

0

0

12.64

33.93

12.83

0

14.76

0

0

10.82

0

14.41

10.24

9.05

23.56

8.27

27.26

17.56

0

9.34

14.03

0

0

25.45

0

8.78

0

IVI

772.22

0

0

17.78

17.78

62.22

20

0

77.78

22.22

0

0

4.44

20

161.11

53.33

0

0

50

11.11

34.44

21.11

4.44

7.78

28.89

0

10

0

123.33

0

0

0

0

0

0

20

0

4.44

0

Den/ha

NC

0

0

0

9.79

10.73

21.22

10.15

0

25.11

11

0

0

4.79

9.83

44.28

18.84

0

0

17.94

8.33

13.85

10.02

4.79

6.2

12.48

0

6.4

0

39.65

0

0

0

0

0

0

9.83

0

4.79

0

IVI

1746

10.15

100.08

1.22

9.01

4.27

1.37

8.63

9.62

59.08

55.42

1.83

5.95

8.32

120.31

291.37

26.56

1.45

18.93

9.16

53.97

23.28

2.9

92.06

28.02

15.95

144.05

48.02

196.49

115.42

2.75

49.16

77.94

22.82

3.05

76.34

3.28

45.8

2.06

Den/ha

ANI

2.961

15.037

2.277

3.637

3.798

2.166

2.734

3.34

8.934

8.87

1.715

2.846

2.555

16.652

32.503

5.721

2.691

5.203

6.445

8.241

4.746

2.627

13.115

5.306

3.841

18.756

7.775

25.037

15.407

3.69

7.792

10.947

4.715

4.089

10.482

9.804

7.352

6.171

IVI



Site wise density, diversity and univariate measures

Site name

Density/hectare



Margalef’s species richness



South Andaman Chidiyatapu Burmanallah Beadonabad

1875 1091 1672

20 18 17

2.56 2.64 2.42

3.06 3.05 2.8

0.65 0.91 0.85

0.09 0.07 0.1

Corbyn’s cove Sippighat Manjeri Guptapara Manglutan Wandoor Ograbraj Bambooflat creek Wright Myo creek Shoal Bay creek Jirkatang Tirur Baratang Middle Strait Wrafter’s creek Baludera Middle Andaman Kadamtala creek

1055 1594 1970 1495 1337 1591 1372 1936 1379 1958 2216 1729

17 18 19 16 18 17 17 17 19 24 21 18

2.34 2.51 2.64 2.46 2.59 2.47 2.48 2.56 2.61 2.67 2.79 2.7

3.04 2.67 2.92 2.54 2.94 3.04 2.9 2.44 3.1 3.65 2.18 2.82

0.82 0.86 0.89 0.88 0.89 0.87 0.15 0.9 0.88 0.82 0.91 0.93

0.13 0.1 0.08 0.1 0.09 0.1 0.1 0.09 0.09 0.09 0.07 0.07

1802 1839 1639

19 20 16

2.53 2.61 2.3

2.77 2.92 2.63

0.85 0.87 0.82

0.1 0.09 0.13

2238

21

2.61

2.98

0.85

0.09

Yerrata creek Shyamkund creek Dhaninallah Creek Rangat Bay Panchwati Mayabunder Austin creek Mohanpur creek Karmatang creek Chainpur creek Rampur Danapur Tugapur creek Diglipur Parangara creek Kishorinagar creek Kalighat creek Smith Island Ariel bay

2288 2252 2383 1558 908

23 22 24 16 10

2.82 2.78 2.85 2.39 1.98

3.27 3.13 3.4 2.53 1.91

0.89 0.89 0.89 0.83 0.85

0.07 0.07 0.07 0.13 0.16

1961 2066 1736 1970 1747 1950 2708

20 22 22 20 19 21 20

2.62 2.76 2.72 2.62 2.72 2.78 2.79

2.89 3.17 3.26 3.08 2.79 3.05 2.93

0.87 0.89 0.88 0.87 0.92 0.91 0.92

0.09 0.07 0.08 0.09 0.07 0.06 0.07

1897 1769 2091 2044 1750

19 18 21 19 18

2.6 2.6 2.75 2.62 2.49

2.75 2.63 2.87 2.72 2.81

0.88 0.9 0.91 0.88 0.86

0.09 0.08 0.07 0.08 0.1

1738 1872 1700 1466

15 18 12 20

2.38 2.54 1.78 2.61

2.43 2.92 2.06 3.67

0.87 0.88 0.71 0.87

0.11 0.09 0.23 0.09

1388 617

19 12

2.48 2.16

3.26 2.55

0.84 0.86

0.11 0.13

Radha nagar 1 Lakshimipur Durgapur Ramnagar Havelock Govind Nagar Radhanagar 2

Author's personal copy P. Ragavan et al. Table 4 (continued) Site name

Neil Island Little Andaman V.K. pur creek Dugong creek Jackson creek Nicobar Islands Car Nicobar Kamorta Katchal Campbell Bay Trinket Island

Density/hectare



Margalef’s species richness



617

13

2.22

2.54

0.86

0.12

2108 1688 1987

20 17 18

2.79 2.5 2.62

3.05 2.79 2.89

0.93 0.88 0.94

0.07 0.1 0.06

950 883

11 8

1.86 2.06

1.94 1.50

0.77 0.99

0.18 0.16

487 862 783

9 15 10

1.76 2.38 2.02

1.67 2.62 1.98

0.8 0.87 0.87

0.21 0.11 0.14

the sites except Corbyn’s Coves, Chidiyatapu, Burmanallah and Beadonabad. In Corbyn’s Cove IVI for Avicennia marina is high, whereas in Burmanallah, Chidiyatapu and Beadonabad IVI for Bruguiera gymnorrhiza is high (Annexure-1). Baratang In Baratang 20 species belonging to 16 genera and 10 families were identified (Table 1). The average tree

Fig. 4 Species composition in Andaman Islands based on IVI percentage

density is 1784/hectare. The Shannon diversity index is 2.58 and Simpson dominance is 0.10 (Table 2). Rhizophora apiculata is the dominant species followed by Bruguiera gymnorrhiza, Ceriops tagal, Rhizophora mucronata, Bruguiera cylindrica and Xylocarpus granatum (Table 3). Rhizophora spp. constitutes 22% of IVI followed by Bruguiera spp. (20%), Ceriops spp. (8%), Xylocarpus spp. (7%) and Avicennia spp. (6%). Among the three sites surveyed in Baratang maximum number of species were recorded from Wrafter’s


creek followed by Middle Strait and Baludera. Shannon diversity index, richness and evenness index is also high in Wrafter’s creek (Table 4). In all the three surveyed sites IVI for Rhizophora apiculata is high followed by Briguiera gymnorrhiza (Annexure-1).

Middle Andaman In Middle Andaman totally 28 species belonging to 18 genera and 12 families were identified (Table 1). The average tree density is 2101/hectare, highest among the 8 divisions. The Shannon diversity index is 2.93 and Simpson dominance is 0.07 (Table 2). Rhizophora apiculata is dominant, followed by Bruguiera gymnorrhiza, Ceriops tagal, Lumnitzera racemosa, Rhizophora mucronata and Xylocarpus granatum (Table 3). Rhizophora spp. constitutes 19% of IVI followed by Bruguiera spp. (14%), Lumnitzera spp. (9%), Ceriops sp (7%) and Xylocarpus spp. (7%). Among the 6 sites surveyed maximum number of species was recorded from the Dhaninallah creek (24 species). Higher diversity, evenness and richness index is also found in Dhaninallah creek. Density per hectare was highest in the Dhaninallah creek (2383/hectare) followed by Yerrata creek and Shyamkund creek (Table 4). Except Rangat Bay and Panchwati IVI for Rhizophora apiculata is high in all the sites, while in Rangat Bay and in Panchwati IVI for Avicennia marina and Excoecaria indica is high respectively (Annexure-1).

Mayabunder In Mayabunder totally 25 species belonging to 18 genera and 12 families were identified (Table 1). Average tree density is 1980/hectare. The Shannon diversity index is 2.83 and Simpson dominance is 0.07 (Table 2). Rhizophora apiculata is dominant followed by Bruguiera gymnorrhiza, Bruguiera cylindrica, Rhizophora mucronata, Xylocarpus granatum and Excoecaria agallocha (Table 3). Rhizophora spp. constitutes 19% of the IVI followed by Bruguiera spp. (18%), Lumnitzera spp. (9%), Ceriops sp (7%) and Xylocarpus spp. (7%). Among the seven sites maximum number of species were recorded from Mohanpur creek and Karmatang creek and tree density is high at Tugapur (2650/hectare). The Shannon diversity index is high at Tugapur (2.79) and species richness is high in Karmatang creek (3.26) (Table 4). In all the sites IVI for Rhizophora apiculata is high in Mayabunder (Annexure-1).

Diglipur In Diglipur totally 25 species belonging to 18 genera and 12 families were identified (Table 1). Average tree density was 1965/hectare. The Shannon diversity index was 2.78 and Simpson dominance was 0.07 (Table 2). Rhizophora apiculata is dominant, followed by Bruguiera gymnorrhiza, Rhizophora mucronata, Ceriops tagal, Bruguiera cylindrica and Xylocarpus granatum (Table 3). Bruguiera spp. constitutes 19% of IVI followed by Rhizophora spp., Ceriops sp, Avicennia spp., Xylocarpus spp., and Acrostichum spp. Among the nine sites surveyed tree density is maximum at the Kalighat creek (2091/hectare) and maximum number of species were also recorded from Kalighat creek followed by Ramnagar. The Shannon diversity and species evenness is high in Kalighat creek and species richness is high at Ramnagar (Table 4). Except Radhanagar, Lakshmipur, Kishorinagar, Ramnagar and Durgapur, in all the sites IVI for Rhizophora apiculata is high. In Radhanagar and Lakshmipur IVI for Acrostichum aureum is high; this suggests the high pace of degradation due of upliftment of land. In Durgapur and Kishorinagar IVI for Rhizophora mucronata is high, whereas in Ramnagar IVI for Bruguiera gymnorrhiza is high (Annexure-1). Havelock In Havelock totally 20 species belonging to 14 genera and 9 families were identified (Table 1). Average tree density is 906/ha. The Shannon diversity index is 2.59 and Simpson dominance is 0.10 (Table 2). Rhizophora apiculata is dominant, followed by Rhizophora mucronata, Lumnitzera littorea, Rhizophora stylosa and Ceriops tagal (Table 3). Rhizophora spp constitutes 41% of IVI followed by Lumnitzera spp., Ceriops spp., Sonneratia spp. and Bruguiera spp. Among the three sites surveyed total tree density is high at Govindnagar (1388/hectare). Maximum number of species and Shannon diversity index are also high in Govindnagar (Table 4). In Govindnagar and Radhanagar IVI for Rhizophora apiculata is high followed by Rhizophora mucronata, while in Neil Island IVI for Rhizophora stylosa is high (Annexure-1). IVI for Rhizophora apiculata species is highest in Havelock division compared to others (Table 3). Little Andaman In Little Andaman totally 20 species belonging to 14 genera and 9 families were identified (Table 1).


Average mangrove plant density is 1962/ha. The Shannon diversity index is 2.76 (Table 2). Rhizophora apiculata is dominant, followed by Bruguiera gymnorrhiza, Acrostichum aureum, Ceriops tagal, Xylocarpus granatum and Bruguiera cylindrica (Table 3). Bruguiera spp. constitutes 18% of the IVI followed by Rhizophora spp. (15%), Sonneratia spp. (9%) Ceriops sp. (8%), Acrostichum spp. (8%) and Xylocarpus spp. (7%). Among the three sites surveyed tree density is high at Vivekanandpur creek. The Shannon diversity index (2.79) and species richness (3.05) is also high in Vivekanandpur creek (Table 4). In Dugong creek and Vivekanandpur Creek IVI for Rhizophora apiculata is high whereas in Jackson creek IVI for Acrostichum aureum is high, in Vivekanandpur creek also A. aureum is dominant next to R. apiculata (Annexure-1). Nicobar In Nicobar division totally 21 species belonging to 11 genera and 9 families were identified (Table 1). Average mangrove plant density is 772 per hectare. The Shannon diversity index is 2.59 and Simpson index is 0.10 (Table 2). Rhizophora mucronata is dominant, followed by Bruguiera gymnorrhiza, Sonneratia caseolaris, Sonneratia lanceolata, Rhizophora apiculata and Nypa fruticans (Table 3). Sonneratia spp. constitutes 29% of IVI followed by Rhizophora spp. (26%), Bruguiera spp. (13%), Lumnitzera spp. (8%) and Nypa sp. (6%) (Fig. 5). Among the five islands surveyed density is high at Car Nicobar (950/hectare). Maximum numbers of species were recorded from Campbell Bay. The Shannon diversity index and species richness is also high in Campbell Bay. IVI for Rhizophora mucronata is high in all the islands except Campbell Bay, where IVI of Sonneratia lanceolata is high (Annexure-1). Bray-Curtis cluster analysis under group average based on the species composition and density observed (Fig. 6) showed that among the eight divisions except Nicobar and Havelock division, all the other divisions are grouped into one major group with 80% similarity. This indicates lack of barrier for spread and distribution among the Andaman islands resulting in uniform distribution of mangroves in the Andaman islands. Havelock (HL) and Nicobar (NC) are outliers, may be due to occurrence of lower species density compared to other divisons. Due to the restricted distribution of certain mangrove species in Nicobar Islands it shows very low similarity (43%) with others. This indicates that mangrove species composition of Nicobar Islands is significantly different from that of Andaman Islands. Cluster dendrogram of surveyed sites also indicates the

same (Fig. 7). Except Pachwati, most of the sites in Andaman Islands are clustered into one group and sites of Havelock and Nicobar divisons form the outliers. Zonation pattern In this study zonation pattern was assessed based on the variation in species composition with respect to proximity to sea. In the Andaman Islands most of the mangroves are of riverine type, where mangroves fringe the banks of the creeks flooded by the intrusion of seawater. Topographically in Andaman Islands coasts are steep and eroding and thus the width of mangrove area is much narrow and highly variable along the creek, usually less than 250 m and rarely exceeding 500 m (Mathew et al. 2010). Generally in riverine type, zonation will be observed both parallel to the shore and along the river/ creek as the creek moves inward, becoming narrow as it progresses, and further more under the influence of fresh water than saline water (Bunt 1996). Based on the vegetative composition on the banks of the creeks and the level of intrusion of seawater we classified the mangrove creeks of Andaman Islands into following three types (Fig. 8). Type 1 - In this kind, creeks are flooded only by the intrusion of seawater up to the tail of the creek during all high tides. e.g., Shoal Bay creek, Yerrata creek, Kadamtala creek, Austin creek, Parangara creek, Kalighat creek, Kishorinagar creek, Mohanpur creek, Karmatang creek. Type 2 - In this kind of creek sea water does not reach the tail of the creek in all high tides except spring tides and tail of the creek is flooded by fresh water streams during rainy season. e.g. Shyamkund creek, Dhaninallah Creek. Tirur creek. Type 3 - In this kind of creek sea water does not reach the tail of the creek and the tail of the creek is flooded by perennial fresh water sources. e.g. Vivekanandpur Creek. In all the three types Sonneratia alba and Avicennia marina form small patches at the mouth of the creek. In downstream and middle estuarine position Rhizophora spp. are fringing the banks of the creek along with Bruguiera spp., Ceriops spp. and Xylocarpus spp. In downstream position R h i z op h o r a m u c ro n at a i s d o m i n a n t a n d Rhizophora spp. forms thickets, depending on the proximity to the sea. The middle estuarine position has tall stands of Rhizophora spp. In type 1 no variation occurs in the vegetative structure at upstream region. In type 2, banks of upstream regions are dominated by Avicennia officinalis along with


Fig. 5 Species composition in Nicobar Islands based on IVI percentage

Excoecaria agallocha, Barringtonia racemosa, Cerbera odollum, Nypa fruticans, Phoenix paludosa and Cynometra iripa. In type 3 banks of upstream regions are dominated by Nypa fruticans, Sonneratia caseolaris, Barringtonia racemosa, Cerbera odollum along with Pheonix paludosa, Cynometra iripa and Xylocarpus granatum. Acanthus ilicifolius and Acrostichum aureum may be common along the banks of creeks and in disturbed areas.

Fig. 6 Cluster dendrogram showing similarity among Divisions

In riverine mangroves parallel zonation is not uniform due to the variable and complex nature of intertidal environment. However, in some of major creeks like Shoal Bay creek, Wrafter’s creek, Kadamtala creek, Yerrata creek and Kalighat creek we observed common distribution pattern of species wherever the width exceeds 200 m. In such areas following zones were observed, i.e., waterfront touching Rhizophora zone followed by Bruguiera zone,

Author's personal copy P. Ragavan et al. Fig. 7 Cluster dendrogram showing similarity among the surveyed sites

Similarity 20

40

60

80

100 Panchawati Campbell bay Katchal Kamorta Trinket Burmanallah Carbyn cove Radhanagar2 Durgapur Radhanagar1 Lakshmipur Cheiyatapu Shoalbay creek Trirur Rangat Bay Ograbranch Bambooflat W rightmyo

Group average

Jirkatang Yerrta Karmatang Creek Kishorinagar Shyamkund

Samples

Aerial bay Tugapur Rampur Danapur Smith island Chainpur creek W rafter Creek Mohanpur creek Middle strait Kadamthala Austin creek Dugong creek V.K.Pur Creek

Parangara creek Kalighat Baludera Guptapara Manjeri Manglutan W andoor Ramnagar Bedonadad Sippighat Carnicobar Govindnagar Neil island

Lumnitzera zone and Avicennia zone towards the land (Fig. 9). The Rhizophora and Bruguiera zones are situated below the high tide level and submerged by sea water twice a day and thus both the zones are swampy in

Transform: Square root Resemblance: S17 Bray Curtis similarity

Jackson creek Dhaninallah

nature. Xylocarpus granatum, X. moluccensis, Sonneratia alba, Acanthus ilicifolius, Ceriops tagal, Scyphiphora hydrophyllaceae and Aegiceras corniculatum are common in Rhizophora and Bruguiera zone.


Fig. 8 Zonation along the creeks in mangroves of Andaman Islands

Lumnitzera and Avicennia zones towards the land are inundated only during spring tide and sometimes by unprecedented sea surges. Hence, these zones are not swampy in nature. Excoecaria agallocha, Hertieria littoralis, Sonneratia ovata, Acrostichum aureum, A. speciosum and Dolichondrone spathaceae are common in Lumnitzera and Avicennia zone. Above the Avicennia zone Phoenix paludosa forms a narrow zone along with Cynometra iripa. In a number of sites Lumnitzera and Avicennia zones are not distinct and often form a mixed zone collectively called backmangrove towards land. Occasionally Avicennia and Lumnitzera zones are replaced with homogenous patches of Excoecaria Fig. 9 Parallel zonation in riverine mangroves of Andaman Islands

agallocha. Similarly, in the same creeks, some of areas lack distinct Rhizophora zone, and in such cases Bruguiera spp. occupies the zone adjoining waterside. In case of mangrove fringing the bays or open coast like Havelock, Neil, Durgapur and Rampur we observed R. mucronata/R. stylosa are dominant towards the seaward side along with Sonneratia alba, Bruguiera spp. and Avicennia marina, followed by Lumnitzera zone and Avicennia zone towards land (Fig. 10). Pemphis acidula, Xylocarpus granatum and Scyphiphora spp. are common in Lumnitzera zone. Sonneratia ovata, Bruguiera cylindrica and Heritiera littoralis are common in Avicennia zone. In some areas like Chidiyatapu where the substratum is muddy (Fig. 11) Sonneratia alba forms homogenous zone towards

Author's personal copy P. Ragavan et al. Fig. 10 Parallel zonation in protected bays with sandy/rocky substrate

the seaward side, followed by Rhizophora zone, Bruguiera zone, Lumnitzera and Avicennia zone. Above the Avicennia zone Phoenix paludosa forms a narrow zone along with Cynometra iripa.

Discussion Among the 38 mangrove species recorded, 34 are classified as true mangrove species by Polidoro et al. (2010) and other four species are natural hybrids (i.e Sonneratia x urama, Sonneratia x gulngai, Rhizophora x annamalayana, Rhizophora x lamarckii) considered as mangrove species (Duke 1992, 2006b; Kathiresan 1995). Tree density in ANI ranged from 0.05 to 0.24 Ind/m2 and average density was 0.17 Ind/m2, which is lower than in the earlier reports except Padalia et al. (2004) (Table 5). Total tree density in ANI was lower than that observed in Thailand (Chasang 1984; Macintosh et al. 2002), Papua New Guinea (Robertson et al. 1991; Johnstone 1983), Indonesia (Hinrichs et al. 2009) and Belize (Murray et al. 2003), ranging between 0.07 and 0.70 Ind./m2. Earlier Mall et al. (1982), Dagar (1982), Dagar and Sharma (1989), Singh et al. (1986), Singh and Garge (1993) assessed the vegetative structure in limited sites in ANI often confined only to South Andaman. Mall et al. (1982) reported almost similar density in South Andaman (1167/hectare). Contemporary to this study Das et al. (2014) assessed the vegetative structure of three sites, one each at South, Middle and North Andaman. The present work was the maiden attempt to provide the vegetative structure for the whole ANI. Hence the present result cannot be discussed elaborately in comparison with earlier accounts and this study provides the first hand information of the vegetative structure of mangroves of ANI. Fig. 11 Parallel zonation in protected bays with muddy substrate

Mangrove of ANI is dense and diverse compared to others mangroves in India (Mandal and Naskar 2008). However 26th December 2004 earthquake followed by a tsunami caused considerable loss in the mangroves of ANI. It was reported that subsidence of coastal land by 1.0 m damaged the mangroves severely due to permanent submergence of its roots in the Southern islands (Malik and Murty 2005; Sankaran 2005; Sivakumar 2007). Similarly, estimated 0.3 to 1.5 m uplift and its easterly tilt in North Andaman (Malik and Murty 2005; Ray and Acharyya 2007, 2011) also affected mangrove vegetation at a few locations in North Andaman Islands. It was variously estimated that up to 20 km2 area was degraded in ANI (Chaudhuri et al. 2009). Particularly in the Nicobar group of islands 60–70% of the mangrove forests got wiped off by the tsunami (Ramachandran et al. 2005; Sridhar et al. 2006). Our result indicates that the overall species richness is still high in ANI, particularly on Nicobar Islands, where 21 species have been registered. Earlier Jagtap (1992) reported 10 species and Dagar et al. (1991) recorded 17 species; recently contemporary to this study Nehru and Balasubramanium (2011) reported 9 species. Among the 21 species, six species viz. Rhizophora x annamalayana, Sonneratia lanceolata, Sonneratia x urama, Sonneratia x gulngai, Sonneratia ovata and Excoecaria indica are new records for India from Nicobar Islands. Particular species like Sonneratia ovata, S. lanceolata, S. x gulngai and S. x urama are reported only in recent times from ANI. Nehru and Balasubramanium (2011) suggested that probable causes for the current occurrence of these species is the dispersal of seeds from the nearest sources viz., Indonesia, Malaysia and Singapore carried by the tsunami. It is felt that the propagule movement could have been due to tidal action and cyclones, but not tsunami, as it does not involve horizontal displacement of water. The possible reason would be is that the destruction due to tsunami would have created spaces for regeneration, and this space


Mangrove tree density per m2 by various studies 2

Reference

Density (Ind/m )

Place

Satyanarayana et al. (2002) Sawale and Thivakaran (2013) Thivakaran et al. (2003) Bhatt and Kathiresan (2011) Das et al. (2014) Mishra et al. (2003) Padalia et al. (2004) Perera et al. (2013) Joshi and Ghose (2014) Upadhyay and Mishra (2014)

0.047–1.7 0.10–0.35 0.08–0.19 0.1740 3.07–5.69 0.71–1.60 0.067 0.13–0.3 0.47–2.37 0.71–1.60

Kakinada bay Kachchh Kachchh Karnataka Andaman Orissa Andaman Sri Lanka Sunderbhan Odisha

would have been used by propagules brought by other means, such as, wave action, cyclones, wind, etc. Recently Nehru and Balasubramanium (2014) reported the high regeneration rate of littoral forest in Nicobar Islands. Earlier Dagar et al. (1991) reported the occurrence of Bruguiera parviflora, B. cylindrica, Xylocarpus granatum and X. moluccensis from Nicobar Islands. But in this study the above said species were not observed in Nicobar Islands. The occurrence of new mangrove species and absence of mangrove species known earlier from the Nicobar Islands shows the possible consequence of the tsunami on the mangrove floral composition of these islands. It was reported by Damroy and Krishnan (2005) that due to subsidence, there might be a change in the composition of mangrove stands. Except in Campbell Bay at all the sites in Nicobar Islands Rhizophora mucronata and Bruguiera gymnorrhiza form a significant part of vegetative structure of mangroves of the Nicobar Islands, while in Campbell Bay Sonneratia spp. particularly Sonneratia lanceolata followed by Sonneratia caseolaris constitutes the major component in vegetative structure. These present observations prove the colonizing ability of Sonneratia spp. in degraded mangrove areas. Hence emphasis needs to be given to Sonneratia spp. in mangrove restoration activity besides Rhizophora spp., Bruguiera spp. and Avicennia spp now being used. Nehru and Balasubraminum (2011) are also of the same view. Similarly, certain areas of South Andaman (e.g. Sippighat and Bambooflat) were also affected by submergence of land; however, there is no such marked variation in species diversity and density compared to other unaffected sites. This is possibly due to recruitment of mangrove vegetation in newly formed intertidal habitats, with seeds from the neighbouring unaffected areas. Findings of Das et al. (2014) also supports this view. In Middle Andaman, except at Panchwati and Rangat Bay, density is high at all other major mangrove areas, ranging

between 2383 and 2238/hectare and Shannon diversity index also high. This shows that there is less disturbance of mangrove of Middle Andaman compared to other divisions. Mayabunder also supports high density and diversity due to the fewer disturbances. In North Andaman certain mangrove areas were affected due to upliftment of land. Upliftment is more on the western side than eastern. Low density and high IVI for Acrostichum aureum in Kishorinagar and Radhanagar mangrove are indicative of high degradation of mangrove areas in the western side. However the newly formed intertidal areas on the banks of the creeks supported recruitment of Rhizophora mucronata by flooding during high tides and at the landward edge species like Avicennia marina, Avicennia officinalis, Bruguiera cylindrica, Aegiceras corniculatum and Excoecaria agallocha were still alive under the influence of agricultural runoff. Central regions are totally absorbed by secondary forest (Fig. 12). On the other hand in mangrove areas of eastern side, i.e. Parangara, Kalighat, Aerial bay and Lakshmipur, the density and diversity are still eminent. However, these areas also degraded due to the flooding only during spring tides; at normal high tides only banks of the creek are flooded. Thus, immediate conservation efforts are required to restore the mangroves in Parangara, Kalighat, Aerial bay and Laxmipur. In Durgapur and Ramnagar low density is attributed to the occurrence mangroves adjoining sandy substratum. In Havelock and Neil islands also mangroves are fringing the sandy shores. Generally mangroves with adjoining sandy areas have less diversity and zonation pattern (Utawale et al. 1973). In ANI tidal inundation plays a major role in zonation of mangrove species. So the classification discussed in this study has some similarity with Watson’s (1928) tidal inundation classes. Rhizophora mucronata/ R. stylosa dominated zone corresponds to Watson Class 1, patch of Sonneratia alba and Avicennia marina at the mouth of the creeks corresponds to Class 2; seaward facing Rhizophora zone and landward facing Bruguiera zone corresponds to Class 3; Lumnitzera and Avicennia zone corresponds to Class 4; Nypa fruticans and Sonneratia caseolaris dominated zone at the upstream position of type-3 creek in Andaman islands corresponds to Class 5. In Nicobar Islands mangroves are found in narrow stretches as the creeks do not penetrate deep inland as in Andaman Islands. In addition mangroves of Nicobar Islands were affected badly by the 26th December 2004 catastrophic events. Hence, no proper zonation was noticed in Nicobar Islands. Of the 38 mangrove species identified in this study, five species are globally considered important with respect to their conservation importance (IUCN 2011). While Sonneratia

Author's personal copy P. Ragavan et al. Fig. 12 Status in uplifted areas (A) revival of Rhizophora mucronata at banks of the creek (B) Central portion devoid of mangrove plants (c) Growth of Avicennia spp at landward edges (D) flowering and fruiting of Aegiceras corniculatum at Landward edges (E) Patch of Bruguiera gymnorrhiza with climbers (F) dead remains of Scyphiphora hydrophyllaceae

griffithii is critically endangered, Excoecaria indica is data deficient. The remaining three species, viz. Brownlowia tersa, Phoenix paludosa and Sonneratia ovata are categorized as Near threatened. In India Avicennia marina and Excoecaria agallocha are at the IUCN category of Lesser risk and all the other mangrove species are at varying level of threat (Kathiresan 2008; Bhatt and Kathiresan 2011). Thus, immediate conservation efforts should be taken to preserve the rich species diversity of ANI.

Conclusion On the whole, our results suggest that the mangroves of ANI are highly diverse. The newly formed inter-tidal areas are more conducive for revival of mangrove species, particularly Sonneratia spp., Rhizophora mucronata in the Nicobar and South Andaman respectively. Mangrove ecosystems are threatened globally due to various anthropogenic activities and global climate change. Adverse effects on mangroves extend their serious consequence to the adjoining fragile and

important ecosystems such as coral reefs and sea grass beds. It is reported that mangrove is the only marginal ecosystem which shares the resources with the adjoining ecosystem (Vannucci 2001). Moreover, the ecological and socioeconomic values offered by the mangroves are innumerable, immeasurable and incomparable. So conserving mangroves might be an agenda in any nation’s conservation programme. It is necessary to collate comprehensive species specific information for mangroves of India, in the absence of which it will be difficult to identify conservation priorities (Kathiresan 2010). The detailed information on diversity, distribution and vegetative structure of all known mangrove species of ANI provided here will eventually help in the long term monitoring of mangrove species.

Acknowledgments We are extremely grateful to the Department of Environment & Forests, Andaman & Nicobar Administration for providing necessary support in conducting the survey.

24.8 24.3

0

66.67

0

0

11.11

5.55

0

155.6

366.7

180.6

Acanthus volubilis

Acrostichum aureum



Avicennia marina


Brownlowia tersa




0 31.8

16.67

125

0

38.88

69.44

0

0

0

0



Excoecaria indica


Lumnitzera littorea

Lumnitzera racemosa

Nypa fruticans

Pemphis acidula

Phoenix paludosa

0 29.6

52.77

0

5.55

0

Rhizophora stylosa




0 0

0

0

0

41.66

0

47.22

0

1875


Sonneratia x gulngai


Sonneratia ovata

Sonneratia x urama

Xylocarpus granatum


9.45

0

10.5

0

0

0

0

180.56

0

Sonneratia alba


2.68

0

10.2

12.9

247.22

66.66



0

0

0

12.1

8.43

0

18.1

5.83

5.12

147.2

13.89

Ceriops tagal

Cynometra iripa

40.6

20.9

0

3.48

6.44

0

0

13.6

0

9.27

36.11


0

0

1091.6

0

20.83

0

50

0

0

0

0

33.33

0

0

0

33.33

58.33

129.16

0

0

12.5

62.5

0

62.5

0

87.5

54.16

8.33

0

0

150

0

0

12.5

87.5

141.66

0

66.66

0

20.83

0

Den/ha


Burmanallah IVI

Chidiyatapu

Den/ha

Annexure-1 Sites wise density and IVI

0

8.82

0

14.3

0

0

0

0

10.7

0

0

0

10.7

15.6

31.7

0

0

8.22

17

0

17

0

22.1

14.7

5.77

0

0

34.9

0

0

8.22

25.1

29.7

0

16.9

0

8.82

0

IVI

1672.22

0

150

0

0

0

0

0

0

27.77

72.22

0

0

22.22

44.44

172.22

0

0

0

0

0

27.77

0

94.44

27.77

0

138.88

177.77

238.88

11.11

0

0

11.11

361.11

0

66.66

0

27.77

0

Den/ha

Beadonadad

0

24.66

0

0

0

0

0

0

9.32

14.63

0

0

7.8

11.57

27.63

0

0

0

0

0

8.2

0

17.59

9.32

0

24.08

28.13

34.46

6.27

0

0

6.27

44.69

0

16.07

0

9.32

0

IVI

1055.55

0

38.88

0

0

0

0

0

0

44.44

0

0

0

11.11

44.44

88.88

0

22.22

16.66

0

0

5.55

0

33.33

16.66

0

11.11

44.44

0

0

0

33.33

283.33

200

0

94.44

0

66.66

0

Den/ha

Corbyn’ cove

0

13.25

0

0

0

0

0

0

14.4

0

0

0

6.24

14.48

23.06

0

12.14

9.49

0

0

4.18

0

12.6

9.49

0

6.84

15.78

0

0

0

12.01

58.17

44.78

0

23.85

0

18.83

0

IVI

Sippighat

1594.44

0

150

0

0

0

0

0

0

38.88

136.11

0

0

0

44.44

313.88

0

0

94.44

0

0

16.66

0

52.77

13.88

0

155.55

77.77

247.22

58.33

0

5.55

11.11

0

0

38.88

0

66.66

72.22

Den/ha

0

25.5

0

0

0

0

0

0

8.89

23.21

0

0

0

10.91

39.17

0

0

16.96

0

0

6.31

0

11.17

5.42

0

23.86

14.89

33.45

12.66

0

3.69

6.9

0

0

10.57

0

22.3

24.08

IVI

Manjeri

1970.83

0

75

0

0

0

0

0

0

33.33

50

0

16.66

50

129.16

370.83

0

0

16.66

0

87.5

29.16

0

141.66

45.83

0

133.33

0

287.5

112.5

0

150

87.5

0

0

104.16

0

50

0

Den/ha

0

13.13

0

0

0

0

0

0

7.91

10.6

0

6.39

10.6

19.06

39.63

0

0

6.39

0

14.83

7.31

0

20

9.62

0

19.44

0

32.97

18.12

0

21.28

14.65

0

0

17.04

0

11.4

0

IVI

Guptapara

1495.83

0

87.5

0

0

0

0

0

0

0

129.16

0

0

0

79.16

329.16

0

0

16.66

0

75

16.66

0

66.66

33.33

0

87.5

0

133.33

87.5

0

50

233.33

0

0

20.83

0

50

0

Den/ha

0

20.05

0

0

0

0

0

0

0

24.15

0

0

0

16.07

45.43

0

0

9.74

0

15.81

6.57

0

14.59

11.62

0

17.12

0

23.68

17.09

0

13.5

35.9

0

0

11.99

0

16.67

0

IVI

Manglutan

1337.5

0

58.33

0

20.83

0

0

0

0

37.5

50

0

0

25

62.5

287.5

0

0

0

0

58.33

25

0

108.33

16.66

0

141.66

0

87.5

95.83

0

66.66

129.16

0

0

50

0

16.66

0

Den/ha

0

13.43

0

13.3

0

0

0

0

10.1

14.59

0

0

9.84

14.06

42.39

0

0

0

0

14.46

7.84

0

21.49

7

0

25.55

0

21.57

20.08

0

14.69

24.17

0

0

14.59

0

10.77

0

IVI

Wandoor

1591.66

0

25

0

16.66

0

0

0

0

25

41.66

0

0

33.33

66.66

316.66

0

0

0

0

0

50

0

158.33

25

0

125

0

300

100

0

75

100

0

0

100

0

33.33

0

Den/ha

0

8.24

0

6.03

0

0

0

0

8.24

10.06

0

0

8.69

13.52

42.44

0

0

0

0

0

11.43

0

28.02

8.24

0

25.18

0

40.11

17.79

0

15.53

17.78

0

0

28.15

0

10.45

0

IVI

Author's personal copy

Diversity, Distribution and Vegetative structure of mangroves of the Andaman and Nicobar Islands, India

0

116.66

188.88

66.66

Brownlowia tersa




0

0

0

66.66

38.88

0

0

0

0

0

0

38.88

0



Sonneratia alba





Sonneratia ovata

Sonneratia x urama

Xylocarpus granatum


1372.22

0


0

Phoenix paludosa

Rhizophora stylosa

42.36

0

Pemphis acidula

272.22

11.11

Nypa fruticans

88.88

0

Lumnitzera racemosa


66.66

Lumnitzera littorea


0

11.11


0

12.98

0

0

0

0

0

0

11.32

15.91

0

0

0

19.35

0

6.46

0

15.66

6.46

0

20.04

94.44

0


9.18

0

32.25

23.17

0

0

18.98

0

0

9.18

Excoecaria indica

16.66

0



30.89

88.88

Avicennia marina

172.22

0


0

0


Ceriops tagal

16.66

Acrostichum aureum

Cynometra iripa

16.57

0

Acanthus volubilis

9.18

16.66


0

0


1936.11

0

113.88

0

0

0

0

0

0

63.88

94.44

0

0

0

105.55

402.77

0

0

44.44

0

0

33.33

0

155.55

33.33

0

158.33

94.44

222.22

186.11

0

33.33

105.55

0

0

50

0

38.88

0

Bambooflat Den/ha

Den/ha

IVI

Ograbraj

0

17.92

0

0

0

0

0

0

13.27

15.58

0

0

0

17.68

42.26

0

0

18.04

0

0

7.97

0

21.31

8.99

0

21.78

15.43

27.78

24.81

0

8.3

16.15

0

0

10.7

0

11.96

0

IVI

Wright Myo creek

1379.16

0

150

0

0

0

0

0

0

58.33

58.33

0

0

0

79.16

287.5

25

0

0

0

25

12.5

0

66.66

12.5

16.66

112.5

50

120.83

129.16

0

0

50

0

33.33

75

0

16.66

0

Den/ha

0

26.88

0

0

0

0

0

0

12.58

12.73

0

0

0

19.09

41.48

7.24

0

0

0

6.73

5.55

0

14.04

5.55

5.34

19.91

11.12

25.57

23.15

0

0

12.91

0

13.5

29.41

0

7.14

0

IVI

Shoal Bay creek

1958.33

0

197.22

0

69.44

0

0

0

0

133.33

94.44

0

5.55

0

119.44

458.33

50

0

8.33

0

44.44

8.33

0

102.78

11.11

0

169.44

47.22

155.66

97.22

0

13.88

50

0

44.44

11.11

52.77

11.11

2.77

Den/ha

0

24.08

0

13.46

0

0

0

0

16.42

14.54

0

2.79

0

16.71

43.47

8.44

0

3.95

0

8.23

3.95

0

14.85

5.11

0

20.90

8.35

19.92

17.38

0

3.87

10.08

0

9.12

5.11

22.54

5.11

1.63

IVI

Jirkatang

2216.66

0

150

0

0

0

0

0

0

75

87.5

0

0

0

75

312.5

16.66

0

62.5

0

75

12.5

0

133.33

37.5

16.66

220.83

79.16

245.83

170.83

0

0

79.16

0

66.66

150

100

50

0

Den/ha

0

17.07

0

0

0

0

0

0

11.19

11.35

0

0

0

10.12

31.3

5.1

0

17.32

0

10.01

3.99

0

17.91

7.16

5.1

25.12

10.39

26.03

20.16

0

0

11.4

0

9.91

24.7

16.91

7.67

0

IVI

Tirur

1729.16

0

145.33

0

150

0

0

0

0

0

70.83

0

0

0

58.33

287.5

66.66

0

45.83

0

0

25

0

95.83

16.66

0

87.5

50

79.16

187.5

0

120.83

75

0

0

100

0

66.66

0

Den/ha

0

23.65

0

21.25

0

0

0

0

0

13.28

0

0

0

13.13

35.51

13.54

0

11.85

0

0

7.12

0

16.54

7.32

0

15.72

10.7

13.47

26.4

0

18.14

14.61

0

0

24.14

0

13.54

0

IVI

Middle Strait

1802.77

0

119.44

0

0

0

0

0

0

100

80.55

0

0

0

219.44

433.33

33.33

0

0

0

77.77

5.55

0

100

22.22

33.33

127.77

33.33

188.88

100

0

11.11

33.33

0

0

50

0

33.33

0

Den/ha

0

20.35

0

0

0

0

0

0

16.26

16.6

0

0

0

26.2

45.05

17.04

0

0

0

17.23

3.25

0

17.32

7.12

8.24

20.98

8.24

25.54

15.19

0

6.01

7.51

0

0

11.61

0

10.19

0

IVI

Wrafter’s Creek

1839.88

44.44

77.77

0

0

0

0

0

0

94.44

52.77

0

0

0

155.55

372.22

33.33

0

0

0

94.44

8.33

0

63.88

8.33

11.11

188.88

52.77

211.11

186.11

0

33.33

58.33

0

0

58.33

0

33.33

0

Den/ha

9.3

13.3

0

0

0

0

0

0

15.57

10.3

0

0

0

22.02

41.61

8.58

0

0

0

15.73

4.81

0

11.63

4.81

6.23

26.36

10.53

29.61

24.56

0

10.54

13.73

0

0

12.09

0

8.58

0

IVI

Baludera

1638.88

5.55

66.66

0

0

0

0

0

0

22.22

33.33

0

0

0

83.33

311.11

27.77

0

0

0

66.66

16.66

0

100

27.77

0

161.11

0

433.33

100

0

0

0

0

0

116.66

0

66.66

0

Den/ha

2.76

12.6

0

0

0

0

0

0

7.53

10.71

0

0

0

16

43.1

9.12

0

0

0

12.6

5.94

0

17.55

7.17

0

30.92

0

52.18

16.91

0

0

0

0

0

34.57

0

20.26

0

IVI


8.57

22.19

0

58.33

0

0

72.22

80.55

0

155.55

216.66

52.77

Acanthus volubilis

Acrostichum aureum



Avicennia marina


Brownlowia tersa




0

2.77


Sonneratia ovata

2238.88

0

0


Xylocarpus mekongensis

0


0

0


136.11

50

Sonneratia alba

Xylocarpus granatum

100


Sonneratia x urama

0


33.33

Phoenix paludosa

38.88

0

Pemphis acidula

0

0

Nypa fruticans


0

Lumnitzera racemosa

Rhizophora stylosa

40.68

180.55

Lumnitzera littorea

469.44

8.33


211.11

0

Excoecaria indica


108.33



8.42

8.33


0

17.95

0

1.6

0

0

0

0

8.21

13.1

0

7.83

0

22.71

0

0

0

19.93

3.83

0

15.1

3.83

4.95

211.11

11.11

Ceriops tagal

Cynometra iripa

25.39

18.85

0

11.13

13.29

0

0

23.92

0

8.42

33.33


0

0


2288.88

125

108.33

0

0

0

0

0

0

80.55

94.44

0

33.33

0

108.33

344.44

33.33

0

8.33

119.44

119.44

5.55

0

105.55

33.33

44.44

241.66

52.77

202.77

211.11

0

50

94.44

0

0

52.77

0

19.44

0

Yerrata creek Den/ha

Den/ha

IVI

Kadamtala

13.77

14.73

0

0

0

0

0

0

10.96

11.39

0

11.49

0

14.37

30.76

7.16

0

3.22

23.29

13.68

2.3

0

14.02

6.02

6.79

24.46

8.744

24.19

21.74

0

7.35

11.27

0

0

10.8

0

6.9

0

IVI

2252.77

11.11

177.77

0

0

0

0

0

0

155.55

44.44

0

0

0

94.44

402.77

63.88

0

0

0

125

13.88

0

119.44

50

11.11

211.11

52.77

180.55

52.77

66.66

125

94.44

52.77

0

33.33

0

113.88

0

Den/ha

Shyamkund creek

3.74

20.8

0

0

0

0

0

0

17.97

7.81

0

0

0

13.38

36.9

10.09

0

0

0

15.81

4.43

0

15.73

8.52

5.56

23.35

9.08

23.63

9.7

13.57

15.57

13.1

8.87

0

6.61

0

15.61

0

IVI

2383.33

22.22

94.44

0

0

0

0

150

0

19.44

47.22

0

0

0

125

438.88

58.33

0

94.44

16.66

44.44

19.44

0

186.44

94.44

16.66

155.55

38.88

219.44

125

0

127.77

94.44

63.88

0

94.44

0

36.11

0

Den/ha

Dhaninallah

4.93

13.41

0

0

0

0

19.6

0

5.25

8.03

0

0

0

15.32

35.7

8.55

0

14.39

7.3

7.65

5.25

0

19.14

11.6

4.62

18.02

7.69

22.88

14.04

0

14.31

11.88

8.97

0

12.3

0

9.05

0

IVI

1558.33

58.33

0

0

0

0

0

0

100

50

0

0

0

70.83

325

50

0

0

0

0

12.5

0

70.83

12.5

16.66

187.5

0

70.83

75

0

0

370.83

0

0

66.66

0

20.83

0

Den/ha

Rangat Bay

0

13.39

0

0

0

0

0

0

20.71

12.26

0

0

0

15.45

46.12

15.59

0

0

0

0

6.99

0

15.21

6.99

6.46

32.84

0

15.87

15.86

0

0

50.07

0

0

15.07

0

11.02

0

IVI

Panchawati

908.33

0

16.66

0

0

0

0

116.66

0

16.66

0

0

0

0

0

50

0

0

0

0

0

141.66

283.33

0

116.66

0

41.66

0

0

0

0

0

0

0

0

91.66

0

33.33

0

Den/ha

0

9.49

0

0

0

0

33.86

0

9.49

0

0

0

0

0

22.77

0

0

0

0

0

50.74

65.98

0

32.68

0

19.45

0

0

0

0

0

0

0

0

39.37

0

16.13

0

IVI

Austin creek

1961.11

0

186.11

0

0

0

0

0

0

50

63.88

0

50

0

180.55

352.77

11.11

0

0

0

66.66

8.33

0

119.44

8.33

25

150

36.11

272.22

125

0

58.33

33.33

0

0

63.88

0

100

0

Den/ha

0

23.61

0

0

0

0

0

0

10.96

11.89

0

10.96

0

24.54366

37.97878

6.788333

0

0

0

12.73049

5.213943

0

17.0899

5.213943

6.461563

19.98019

8.460882

31.50997

18.25

0

11.1

8.9

0

0

11.65

0

16.79

0

IVI

2066.66

33.33

125

0

0

0

0

0

0

125

66.66

0

0

0

155.55

344.44

33.33

13.88

0

0

94.44

11.11

0

155.55

33.33

11.11

186.11

50

216.66

155.55

0

50

69.44

38.88

0

58.33

0

38.88

0

Den/ha

Mohanpur creek

6.82

17.36

0

0

0

0

0

0

16.79

10.71

0

0

0

19.85

34.52

7.64

6.86

0

0

13.52

5.58

0

20.81

9.43

5.58

21.79

9.65

27.32

18.70

0

9.50

11.04

8.66

0

10.04

0

7.82

0

IVI

Karmatang Creek

1736.11

22.22

125.00

0

0

0

0

0

0

0

94.44

0

0

0

105.56

308.33

19.44

0

8.33

127.78

94.44

8.33

0

63.89

8.33

33.33

125.00

97.22

213.89

94.44

0

25.00

16.67

33.33

0

66.66

0

44.44

0

Den/ha

5.42

21.41

0

0

0

0

0

0

0

16.71

0

0

0

17.13

36.81

5.44

0

3.77

20.06

21.92

3.77

0

12.34

3.77

7.28

22.46

15.82

30.68

17.18

0

6.66

4.83

7.23

0

10.95

0

8.36

0

IVI



13.37 13.70

66.66

0

75.00

Acrostichum aureum



6.45

21.49 5.03

0

150.00

287.50

54.16

150.00

Brownlowia tersa




Ceriops tagal

0

16.66

370.83

75.00

0

0

0

50.00

100.00

0

0

0

0

0

0

150.00

25.00

Pemphis acidula

Phoenix paludosa



Rhizophora stylosa




Sonneratia alba





Sonneratia ovata

Sonneratia x urama

Xylocarpus granatum


1970.83

0

Nypa fruticans

17.06

100.00

0

16.66


Lumnitzera littorea

0

Excoecaria indica

Lumnitzera racemosa

6.46

150.00


6.44

23.88

0

0

0

0

0

0

15.41

9.69

0

0

0

14.25

38.65

6.46

0

0

0

0

20.47

5.03

12.50

12.50

Cynometra iripa


9.76

32.58

19.21

0

0

91.66

0

Avicennia marina


0

14.60

0

16.66

0


0

Acanthus volubilis

0

1747.22

0

100.00

0

0

0

0

0

0

58.33

122.22

0

0

0

100.00

211.11

33.33

0

0

0

105.55

16.66

0

100.00

11.11

16.66

211.11

100

197.22

113.88

0

50.00

100.00

0

0

66.66

0

33.33

0

Den/ha


Rampur

Den/ha

IVI

Chainpur creek

0

15.80

0

0

0

0

0

0

12.61

18.12

0

0

0

17.58

27.69

11.21

0

0

0

16.37

6.11

0

15.80

6.67

6.11

27.01

17.58

27.84

21.00

0

10.04

17.05

0

0

14.13

0

11.21

0

IVI

Danapur

1950

0

58.33

0

0

0

0

0

0

88.89

122.22

0

0

38.89

100.00

213.89

33.33

0

0

0

122.22

11.11

0

66.67

8.33

11.11

183.33

33.33

100.00

183.33

0

105.55

197.22

0

0

155.55

0

16.66

0

Den/ha

0

11.52

0

0

0

0

0

0

20.41

16.29

0

0

9.62

14.14

29.72

8.42

0

0

0

16.67

4.84

0

10.89

3.78

4.84

25.23

8.42

14.90

21.87

0

24.42

14.31

0

0

19.41

0

4.83

0

IVI

Tugapur

2708

16.66

120.83

0

0

0

0

0

0

87.50

150.00

0

0

0

91.66

325.00

50.00

0

0

0

150.00

16.66

0

108.33

45.83

29.18

150.00

58.33

275.00

316.66

0

183.33

150.00

0

0

233.33

0

150.00

0

Den/ha

10.60

15.28

0

0

0

0

0

0

10.60

15.28

0

0

0

11.80

29.76

10.49

0

0

0

19.02

6.21

0

14.57

7.88

5.33

17.22

12.07

24.81

25.84

0

17.44

16.21

0

0

20.67

0

15.63

0

IVI

Parangara creek

1897.22

47.22

100.00

0

0

0

0

58.33

0

0

30.55

0

0

0

100.00

330.55

33.33

0

0

0

0

38.88

0

119.44

25.00

38.88

213.88

94.44

336.11

141.66

0

33.33

58.33

0

0

38.88

0

58.33

0

Den/ha

9.61

16.97

0

0

0

0

10.98

0

0

7.33

0

0

0

15.96

38.48

12.09

0

0

0

0

9.42

0

17.92

7.44

9.43

27.01

15.05

38.58

19.79

0

12.09

11.00

0

0

9.42

0

11.40

0

IVI

Kishorinagar

1769.44

0

88.88

0

0

0

0

0

0

58.33

30.55

0

0

0

294.44

161.11

0

0

0

0

52.78

33.33

0

58.33

44.44

30.56

205.56

58.33

219.44

47.22

0

116.66

97.22

0

0

136.11

0

36.11

0

Den/ha

0

16.02

0

0

0

0

0

0

12.49

9.11

0

0

0

36.67

24.03

0

0

0

0

13.18

8.78

0

12.66

10.22

8.13

28.72

12.12

29.71

10.74

0

19.13

17.07

0

0

21.53

0

9.71

0

IVI

Kalighat

2091

11.11

155.55

0

0

0

0

58.33

0

0

30.55

0

0

0

136.11

330.55

50

0

0

0

0

33.33

0

158.33

58.33

38.88

161.11

63.88

258.33

97.22

33.33

110.00

63.88

38.88

0

94.44

0

119.44

0

Den/ha

4.89

19.25

0

0

0

0

11.24

0

0

7.87

0

0

0

18.31

33.16

14.51

0

0

0

0

7.06

0

19.34

10.27

7.86

20.03

10.95

27.56

14.14

8.47

14.37

10.53

8.15

0

15.43

0

16.52

0

IVI

2044.44

5.55

180.55

0

0

0

0

0

0

80.55

58.33

0

0

0

208.33

352.77

0

0

0

0

0

33.33

0

105.55

11.11

58.33

247.22

63.88

213.88

125.00

0

94.44

63.88

47.22

0

63.88

0

30.55

0

Den/ha

Smith Island

2.56

23.86

0

0

0

0

0

0

15.18

12.82

0

0

0

24.16

36.04

0

0

0

0

0

7.63

0

14.94

6.63

10.99

27.36

11.18

24.46

17.59

0

13.84

10.71

9.61

0

20.23

0

10.14

0

IVI

1750

0

129.16

0

0

0

0

0

0

91.66

16.66

0

0

0

79.16

329.16

16.66

0

0

0

66.66

8.33

0

50.00

79.16

16.66

150.00

0

279.16

233.33

0

50.00

87.50

0

0

50.00

0

16.66

0

Den/ha

Arial bay IVI

0

24.91

0

0

0

0

0

0

17.82

7.05

0

0

0

16.12

41.57

7.05

0

0

0

16.01

3.95

0

10.65

13.75

7.05

23.78

0

35.55

29.35

0

10.65

15.29

0

0

12.43

0

7.05

0


22.22

0

16.66

61.11

0

22.22

0

0

0

0

116.66

100.00

133.33

0

0

0

0

0

0

0

00

0

0

0

66.66

0

Ceriops tagal

Cynometra iripa



Excoecaria indica


Lumnitzera littorea

Lumnitzera racemosa

Nypa fruticans

Pemphis acidula

Phoenix paludosa



Rhizophora stylosa




Sonneratia alba





Sonneratia ovata

Sonneratia x urama

Xylocarpus granatum


1738.88

100.00

0


338.88



0

Brownlowia tersa

19.02

100.00

22.22


116.66

0


Avicennia marina

322.22

Acrostichum aureum


10.09

0

Acanthus volubilis

0

14.74

0

0

0

0

0

0

0

0

0

0

0

21.70

17.84

21.09

0

0

0

0

10.09

0

13.00

7.83

0

10.09

0

18.05

41.89

0

21.89

0

42.89

0

29.84

200.00


0

0


1872.22

0

66.66

0

0

0

0

0

0

44.44

66.66

0

0

0

133.33

100.00

116.66

0

0

0

0

22.22

0

61.11

16.66

22.22

22.22

0

100.00

338.88

0

116.66

100.00

22.22

0

322.22

0

200.00

0

Lakshmipur Den/ha

Den/ha

IVI

Radhanagar 1

0

12.80

0

0

0

0

0

0

10.64

12.80

0

0

0

19.31

15.95

18.43

0

0

0

0

8.47

0

11.63

6.60

8.47

8.47

0

16.25

37.88

0

20.02

17.31

8.47

0

39.25

0

27.17

0

IVI

Durgapur

1700

0

33.33

0

0

0

0

0

0

66.66

0

0

0

0

633.33

508.33

0

16.66

0

0

0

0

0

91.66

0

8.33

33.33

0

91.66

0

0

0

100.00

0

0

91.66

0

25.00

0

Den/ha

0

12.39

0

0

0

0

0

0

16.91

0

0

0

0

75.07

64.63

0

7.30

0

0

0

0

0

19.58

0

4.76

12.39

0

25.99

0

0

0

20.92

0

0

30.18

0

9.84

0

IVI

Ramnagar

1466

50

66.66

0

0

0

0

16.66

0

16.66

0

0

0

0

33.33

150

33.33

0

16.66

0

0

16.66

0

133.33

25

16.66

100

258.33

225

91.66

0

0

33.33

25

0

100

0

58.33

0

Den/ha

13.00

14.92

0

0

0

0

6.50

0

6.50

0

0

0

0

11.56

26.23

11.56

0

6.50

0

0

6.50

0

23.01

9.03

6.50

20.32

34.26

36.43

17.78

0

0

9.09

8.01

0

19.00

0

13.20

0

IVI

Govindnagar

1388.89

0

16.66

0

0

0

0

0

0

66.66

88.88

16.66

50

100

166.66

361.11

0

22.22

0

0

188.89

44.44

0

16.66

11.11

0

100

0

33.33

38.88

0

0

16.66

0

0

27.77

0

22.22

0

Den/ha

0

5.95

0

0

0

0

0

0

17.73

17.34

6.18

14.23

19.23

30.9

5.38

0

9.57

0

0

36.36

12.01

0

7.45

5.32

0

19.29

0

9.9

10.99

0

0

7.45

0

0

8.47

0

9.57

0

IVI

Radhanagar 2

616.66

0

25

0

50

0

0

0

0

0

0

0

0

0

91.66

158.33

0

0

0

0

0

16.66

0

25

8.33

0

58.33

0

108.33

25

0

0

0

0

0

33.33

0

16.66

0

Den/ha

0

16.95

0

30.95

0

0

0

0

0

0

0

0

0

40.67

57.08

0

0

0

0

0

12.28

0

16.95

7.61

0

26.02

0

44.32

16.95

0

0

0

0

0

17.92

0

12.28

0

IVI

Neil Island

616.66

0

11.11

0

0

0

0

0

0

38.88

0

105.55

5.55

155.55

16.66

105.55

0

22.22

0

0

0

61.11

0

0

0

0

22.22

0

33.33

0

0

0

0

0

0

27.77

0

11.11

0

Den/ha

0

9.77

0

0

0

0

0

0

18.3

0

36.33

5.63

54.77

13.91

44.84

0

18.05

0

0

0

28.4

0

0

0

0

18.05

0

18.63

0

0

0

0

0

0

22.19

0

9.77

0

IVI

V.K.Pur Creek

2108.33

0

133.33

0

0

0

0

4.16

116.66

66.66

0

0

0

0

79.16

329.16

108.33

0

100

0

0

75

0

100

50

58.33

233.33

50

191.66

116.66

0

50

95.83

0

0

100

0

50

0

Den/ha

0

19.43

0

0

0

0

1.94

14.54

10.95

0

0

0

0

11.27

31.75

14.08

0

13.91

0

0

12.49

0

14.73

10.24

9.19

23.79

8.25

23.10

17.32

0

8.7

13.98

0

0

31.67

0

8.7

0

IVI



329.16

79.16

0

0

0

0

66.66

0

0

0

0

0

0

133.33

0



Rhizophora stylosa




Sonneratia alba





Sonneratia ovata

Sonneratia x urama

Xylocarpus granatum


1987

108.33

Phoenix paludosa

14.75

100

0

Nypa fruticans

Pemphis acidula

0

0

20.47

0

0

0

0

0

0

11.62

0

0

0

0

11.91

33.55

14.92

0

0

15.52

10.88

9.74

0

58.33

Cynometra iripa

25.16

0

233.33

Ceriops tagal

8.73

24.36

0

50


Lumnitzera littorea

191.66


18.25

Lumnitzera racemosa

116.66


9.22 0

13.16

0

Brownlowia tersa

75

50


14.74

0

95.83

Avicennia marina

0

0


0


Excoecaria indica

0


33.72

50

100

Acrostichum aureum

9.22 0

100

0

Acanthus volubilis


50


0


0


1688

0

150

0

00

0

0

0

0

66.66

0

0

0

0

100

311.11

100

0

0

0

0

16.66

0

88.88

22.22

22.22

127.77

27.77

311.11

100

0

44.44

88.88

0

0

88.88

0

22.22

0

Dugong creek Den/ha

Den/ha

IVI

Jackson creek

0

27.11

0

0

0

0

0

0

12.77

0

0

0

0

16.73

40.42

16.96

0

0

0

0

6.51

0

19.28

8.32

8.32

22.74

7.53

40.42

18.03

0

10.74

16.44

0

0

19.28

0

8.32

0

IVI

Car Nicobar

950

0

0

0

0

0

0

0

0

0

0

0

22.22

100

288.88

200

0

0

0

33.33

83.33

11.11

0

0

0

0

0

0

177.77

0

0

0

0

0

0

16.66

0

11.11

0

Den/ha

0

00

0

0

0

0

0

0

0

0

0

12.14

30.94

66.13

52.58

0

0

0

18.24

27.92

10.5

0

0

0

0

0

0

49.2

0

0

0

0

0

0

15.01

0

10.5

0

IVI

Kamorta

883

0

0

0

0

0

0

0

200

100

0

0

0

0

200

0

0

0

91.66

0

58.33

0

0

16.66

41.66

0

0

0

175

0

0

0

0

0

0

0

0

0

0

Den/ha

0

0

0

0

0

0

0

55.47

34.51

0

0

0

0

58.81

0

0

0

37.66

0

24.04

0

0

12.58

20.23

0

0

0

54.67

0

0

0

0

0

0

0

0

0

0

IVI

Katchal

487.5

0

0

0

66.66

0

0

0

50

16.66

0

0

0

0

175

0

0

0

25

0

12.5

16.66

0

0

8.33

0

0

0

116.66

0

0

0

0

0

0

0

0

0

0

Den/ha

0

0

0

39.6

0

0

0

32.47

21.01

0

0

0

0

79.23

0

0

0

20.86

0

16.45

16.38

0

0

11.89

0

0

0

62.07

0

0

0

0

0

0

0

0

0

0

IVI

Campbell Bay

862.5

0

0

66.66

0

233.33

75

0

75

0

0

0

0

0

12.5

50

0

0

66.66

0

0

54.16

16.66

8.33

58.33

0

25

0

50

0

0

0

0

0

0

62.5

0

0

8.33

Den/ha

0

0

22.26

0

54.29

24.09

0

27.53

0

0

0

0

0

10.09

19.57

0

0

24.74

0

0

19.65

9.49

7.17

21.08

0

11.95

0

19.42

0

0

0

0

0

0

21.43

0

0

7.17

IVI

Trinket Island

783.33

0

0

0

0

0

0

0

133.33

33.33

0

0

0

0

200

0

0

0

100

33.33

50

0

0

25

33.33

0

25

0

150

0

0

0

0

0

0

0

0

0

0

Den/ha

IVI

0

0

0

0

0

0

0

42.64

19.87

0

0

0

0

61.42

0

0

0

35.05

19.87

22.26

0

0

15.73

17.06

0

15.73

0

50.38

0

0

0

0

0

0

0

0

0

0



References Aksornkoae S (1993) Ecology and management of mangroves. Gland, Switzerland, IUCN, Wetlands and Water Resources Programme Aragones EG, Rojo JP, Pitargue FC (1998) Botanical identification handbook on Philippine mangrove trees. Forest Products Research and Development Institute, Department of Science and Technology, Laguna, the Philippines, 127 pp Banerjee LK, Sastry ARK, Nayar MP (1989) Mangroves in India Identification Manual. Botanical Survey of India, Calcutta, India Bhatt JR, Kathiresan K (2011) Biodiversity of Mangrove Ecosystems in India. In Towards Conservation and Management of Mangrove Ecosystems in India/ed. by Bhatt J R., Macintosh D. J., Nayar T. S., Pandey C. N. and B. P. Nilaratna, IUCN India Blasco (1977) Outline of ecology, botany and forestry of mangals of the Indian subcontinent. In (V.J. Chapman. Wet. Coastal ecosystem. Elsevier. Amstardam), 260p Bunt JS (1996) Mangrove Zonation: An Examination of Data from Seventeen Riverine Estuaries in Tropical Australia. Annals of Botany 78:333–341 Bunt JS, Bunt ED (1999) Complexity and variety of zonal pattern in the mangroves of Hinchinbrook area. Notheastern Australia. Mangroves and salt marshes 3:165–176 Bunt JS, Stieglitz T (1999) Indicators of mangrove zonality: The Normanby river, N.E.Australia. Mangroves and Salt marshes 3: 177–184 Bunt JS, Williams WT (1981) Vegetational relationships in the mangroves of tropical Australia. Marine Ecology - Progress Series 4: 349–359 Bunt JS, Williams WT, Hunter JF, Clay HJ (1991) Mangrove sequencing: analysis of zonation in a complete river system. Marine ecology press series. 72:289–294 Chapman VJ (1975) Mangrove Biogeography. In: Walsh GE, Snedaker SC, Teas HJ (eds) Proceedings of the International Symposium on Biology and Management of Mangroves, vol 1. Gainesville Univ, Florida, pp. 3–22 Chapman VJ (1976b) Mangrove Vegetation. J. Cramer, Valduz, 447 pp. Chapman VJ (1976c) Coastal Vegetation. Pergamon Press, 292 pp. Chapman VJ (1977a) Mangrove Vegetation. Cramer, Valduz Chapman VJ (ed.) (1977b) wet coastal ecosystems. Ecosystems of the World: 1. Elsevier Scientific Publishing Company, 428 pp. Chapman VJ (1976a) Mangrove biogeography. In: Chapman VJ (ed) Wet Coastal Ecosystems. Elsevier Sci. Pub. Co., Amsterdam, pp. 1–29 Chasang H (1984) Structure of a mangrove forest at Ko Yao Yai, Southern Thailand. In: Soepadmo E, Rao AN, Macintosh DJ (eds) Proceedings of the Asian symposium on mangrove environment research and management. Kuala Lumpur 1980. University of Malaya and UNESCO Chaudhuri SG, Dinesh R, Sheeja TE (2009) Physico-chemical, biochemical and microbial characteristics of soils of mangroves of the Andamans: a post-tsunami analysis. Current Science 97:98–102 Clarke KR, Gorley RN (2006) PRIMER v6: user manual/tutorial. PRIM ER-E, Plymouth, p. 192 Curtis JT, Mclntosh RP (1950) The interrelationships of certain analytic and synthetic Phytosocioogical characters. Ecology 31:434–455 Dagar JC (1982) Some ecological aspects of mangrove vegetation of the Andaman and Nicoabr Islands in India. Sylvatrop Phillip.For.Res.J. 7:177–216 Dagar JC, Dagar HS (1986) Mangroves and Some coastal plants in Enthnobotany of tribals of Andaman and Nicobar Islands. Journal of Andaman Science Association 2:33–46 Dagar JC, Mongia AD, Bandhyopadhyay AK (1991) Mangroves of Andaman and Nicobar Islands., (Oxford and IBH, New Delhi), 166p.

Dagar JC, Sharma AK (1989) Impact of developmental activities on the litter fall and mangal formation in the Andaman’s. Paper presented in Symposium BDecelopment Vis a Vis Ecology; ITACH. Forest Department. Port Blair Dagar JC, Singh NT (1999) Plant resources of the Andaman and Nicobar Islands. Introduction, General Features, Vegetation and Floristic Elements Vo. 1 and 2. Bishen Singh ahendra Pal Singh, Dehra Dun. Dam Roy S (1995a) Mangrove ecology of Alexandra Island and Manjeri area of South Andaman. Journal of Andaman Science Association 11:58–61 Dam Roy S (1995b) Studies on Mangrove ecology of Chouldari area, South Andaman. Journal of Andaman Science Association 11:29– 33 Dam Roy S, Krishnan P, George G, Kaliyamoorthy M, Goutham Bharathi MP (2009) Mangroves of Andaman and Nicobar Islands, A field guide. Central Agricultural Research Institute. pp63. Damroy S, Krishnan P (2005) Mangrove stands of Andamans vis-à-vis tsunami. Current Science 89:1800–1804 Das AK, Jha DK, Prashanthi Devi M, Sahu BK, Vinithkumar NV, Kirubagaran R (2014) Post tsunami mangrove evaluation in coastal vicinity of Andaman Islands. India. Journal of Coastal Conservation. DOI. doi:10.1007/s11852-014-0312-5 Dash MC, Dash SP (2009) Fundamentals of Ecology. Tata McGraw-Hill Education. Pp557. Debnath HS (2004) Mangroves of Andaman and Nicobar Islands; Taxonomy and Ecology (A community profile). Bishen singh mahendra pal singh, Dehra Dun Duke NC (1991) A systematic revision of the mangrove genus Avicennia (Avicenniaceae) in Australasia. Australian Systematic Botany 4: 299–324 Duke NC (1992) Mangrove floristics and biogeography. In: Robertson AI, Alongi DM (eds) Tropical mangrove ecosystems. American Geophysical Union, Washington DC, USA, pp. 63–100 Duke NC (2006a) Australia’s Mangroves: the Authoritative Guide to Australia’s Mangrove Plants. University of Queensland, St Lucia, Australia, pp. 29–39 Duke NC (2006b) Indo-West Pacific stilt mangroves: Rhizophora apiculata, R. mucronata, R. stylosa, R. annamalai, R. lamarckii. In: Elevitch CR (ed) Traditional trees of Pacific Islands: their culture, environment, and use: Permanent Agriculture Resources. Hawaii, Holualoa, pp. 641–660 Duke NC, Ball MC, Ellison JC (1998) Factors influencing biodiversity and distributional gradients in mangroves. Global Ecology and Biogeography 7:27–47 Duke NC, Bunt JS (1979) The genus Rhizophora (Rhizophoraceae) in northeastern Australia. Australian Journal of Botany 27:657–678 Duke NC, Jackes BR (1987) A systematic revision of the mangrove genus Sonneratia (Sonneratiaceae) in Australasia. Blumea. 32: 277–302 Ellis JL (1987) Floral composition of the near shore vegetation of the Andaman’s. In: N.T. Singh, B. Gangwar, G.C. Rao and R. Soundararajan (eds.), Proc. Symp. Management of Coastal Ecosystems and Oceanic Resources of the Andamans, 24–27. Ellison AM, Farnsworth EJ, Merkt RE (1999) Origins of mangrove ecosystems and the mangrove biodiversity anomaly. Global Ecology and Biogeography 8:95–115 Ellison AM, Fransworth EJ (2001) Mangrove communities. In: Bertness MD, Gaines S, Hay ME (eds) Marine community ecology. Sinauer Press, Sunderland, Massachusetts, USA, pp. 423–442 Ellison AM, Mukherjee BB, Karim A (2000) Testing patterns of zonation in mangroves: Scale dependence and environmental correlates in the sundarbans of Bangladesh. Journal of Ecology. 88:813–824 FAO (2003) Status and trends in mangrove area extent worldwide. In: Wilkie ML, Fortuna S (eds) Forest Resources Assessment working Paper No. 63.Rome: (Forest Resources Division, FAO), 87p.

Author's personal copy P. Ragavan et al. FAO (2007) The world’s Mangroves 1980–2006, FAO Forestry paper 153. Rome: (Forest resources division, FAO), 77p Field CD (1995) Journey amongst Mangroves. Okinawa, Japan: International Society for Mangrove Ecosystems.137 pp. FSI (2013) Status of forest report. Forest Survey of India (FSI), Dehra Dun Giesen W, Wulffraat S, Zieren M, Scholten L (2006). Mangrove guidebook for Southeast Asia. FAO and Wetlands International, (RAP publication. Thailand) Goutham-Bharathi MP, Kaliyamoorthy M, Dam Roy S, Krishnan P, George G, Murugan C (2012) Sonneratia ovata (Sonneratiaceae)A New Distributional Record for India from Andaman and Nicobar Islands. Taiwania 57:406–409 Goutham-Bharathi MP, Dam Roy S, Krishnan P, Kaliyamoorthy M, Immanuel T (2014) Species diversity and distribution of mangroves in Andaman and Nicobar Islands, India. Botanica Marina 57:421– 432 Hajra PK, Rao PSN, Mudgal V (1999) Flora of Andaman and Nicobar Islands Vol. 2. Botanical Survey of India, Calcutta Hinrichs S, Nordhaus I, Geist SJ (2009) Status, diversity and distribution patterns of mangrove vegetation in the Segara Anakan lagoon, Java, Indonesia. Regional Environmental Change 9:275–289 IUCN (2011) The IUCN red list of threatened species. Version 2011.2. Electronic database accessible at http://www.iucnredlist.org Jagtap TG (1992) Marine flora of Nicobar group of islands in Andaman sea. Indian Journal of Marine Science. 21:56–58 Johnstone IM (1983) Succession in zoned mangrove communities: where is the climax? In: Teas HJ (ed) Tasks for vegetation science 8. Dr W. Junk Publishers, The Hague, pp. 131–139 Joshi HG, Ghose M (2014) Community structure, species diversity, and aboveground biomass of the Sundarbans mangrove swamps. Trop Ecol 55:283–303 Kathiresan K (2010) Importance of mangrove forest of India. Journal of Costal Environment 1:11–26 Kathiresan K (1995) Rhizophora annamalayana: a new species of mangroves. Environment and Ecology 13:240–241 Kathiresan K (2000) Mangrove and associate plant species. Flora and Fauna in mangrove ecosystems: A manual for Identification, 68– 117. Kathiresan K (2002) Manual on identification of mangroves and associate plant species. All India Co‐ordinated Project on BSurvey and Inventorization of Coastal and Marine Biodiversity (East Coast), 49p. Kathiresan K (2008) Biodiversity of Mangrove Ecosystems. Proceedings of Mangrove Workshop, GEER Foundation, Gujarat, India Kloss (1902) The Andaman and Nicobar. Vivek publishing house. New Delhi. 373pp. Macintosh DJ, Ashton EC, Havanon S (2002) Mangrove rehabilitation and intertidal biodiversity: a study in the Ranong mangrove ecosystem, Thailand. Estuar Coast Shelf Sci 55:331–345. doi:10.1006/ ecss.2001.0896 Macnae W (1966) Mangroves in eastern and southern Australia. Australian Journal of Botany 14:67–104 Malik JN, Murty CVR (2005) Landscape changes in Andaman and Nicobar Islands (India) due to Mw 9.3 tsunamigenic Sumatra earthquake of 26 December 2004. Current Science 88:1384–1386 Mall LP, Billore SK, Amritphale AD (1982) Certain ecological observation on mangroves of Andaman Islands. Tropical Ecology 23:225– 233 Mall LP, Singh VP, Garge A (1991) Study of biomass, litter fall, litter decomposition and soil respiration in monogeneric mangrove and mixed mangrove forests of Andaman islands. Tropical Ecology 32: 144–152 Mall LP, Singh VP, Garge A, Pathak SM (1985) A new approach towards the mangrove forests flora of Andaman Island. Indian Forester. 111:

Mall LP, Singh VP, Pathak SM, Garge A, Jat MS, Mukesh laskari (1987) Ecological studies of mangrove forest ecosystem of Andaman and Nicobar Islands. Final technical report. MAB project No.F 20/3/79 ENV. School studies in Botany. Vikaram University, Ujjain 456010. India. Mandal RN, Naskar KR (2008) Diversity and classification of Indian mangroves: a review. Tropical Ecology 49:131–146 Margalef FR (1978) Information theory in ecology. Gen. Syst 3:36–71 Mathew G, Jeyabaskaran R, Prema D (2010) Mangrove ecosystem in India and their conservation. Central Marine Fisheries Research Institute eprints. 191-199 Mishra PK, Sahu JR, Upadhyay VP (2003) Species diversity in Bhitarkanika Mangove ecosystem in Orissa, India. Lyonia 8:73–87 Misra R (1968) Ecology workbook. Oxford and IBH publishing company. Ltd, New Delhi Muller-Dombois, Ellenberg H (1974) Aims and Methods of Vegetation Ecology. John Wiley and Sons, New York Murray MR, Zisman SA, Furley PA, Munro DM, Gibson J, Ratter J, Bridgewater S, Minty CD, Place CJ (2003) The mangroves of Belize Part 1. distribution, composition and classification. For Ecol Manage 174:265–279 Nehru P, Balasubramanian P (2011) Re-colonizing mangrove species in tsunami devastated habitats at Nicobar Islands, India. CheckList 7: 253–256 Nehru P, Balasubramanian P (2012) Sonneratia ovata Backer (Lythraceae): status and distribution of a Near Threatened mangrove species in tsunami impacted mangrove habitats of Nicobar Islands, India. Journal of Threatened Taxa 4:3395–3400 Nehru P, Balasubramanium P (2014) Recovery rate of vegetation in the tsunami impacted littoral forest of Nicobar Islands, India. Forest Ecology and Management 313:243–253 Padalia H, Chauhan N, Porwal MC, et al (2004) Phytosociological observations on tree species diversity of Andaman Islands, India. Current Science 87:799–806 Parkinson CE (1923) A Forest Flora of the Andaman Islands. Bishen Singh and Mahendrapal Singh, Dehradun Perera KARS, Amarasinghe MD, Somaratna S (2013) Vegetative structure and species distribution of mangroves along the soil salinity gradient in a micro tidal estuary on the Noth-Western coast of Sri Lanka. Am J Marine Sci 1:7–15 Pielou EC (1966) The measurements of diversity in different types of biological collections. J. Theor. Biol 13:131–144 Polidoro BA, Carpenter KE, Collins L, Duke NC, Ellison AM, Ellision JC, Farnsworth EJ, Fernando ES, Kathiresan K, Koedam NE, Livingstone SR, Miyagi T, Moore GE, Nam VN, Ong JE, Primavera JH, Salmo SG, Sanciangco JC, Sukardjo S, Wang Y, Yong JWH (2010) The loss of species: Mangrove extinction risk and geographic areas of global concern. PLoS ONE 5:1–10 Ragavan P, Ravichandran K, Mohan PM, Sxaena A, Prasanth RS, Jayarai RSC, Saravanan S (2014b) New distributional records of Sonneratia spp. from Andaman and Nicobar Islands, India. Biodiversitas 15: 250–259 Ragavan P, Ravichandran K, Mohan PM, Sxaena A, Prasanth RS, Jayarai RSC, Saravanan S (2015) Note on Excoecaria indica (Willd.) Muell.-Arg, 1863 (Euphorbiaceae), from the Andaman and Nicobar Islands, India; a data deficient species. Biodiversitas 16: 22–26 Ragavan P, Saxena M, Saxena A, Mohan PM, Sachithanantham V, Coomar T (2014a) Floral composition and taxonomy of mangroves of Andaman and Nicobar Islands. Indian journal of geo magarine science, Vol 43:1031–1044 Ramachandran S, Anitha S, Balamurugan V, Dharanirajan K, Vendhan KE, Divien MIP, Vel AS, Hussain IS, Udayaraj A (2005) Ecological impact of tsunami on Nicobar Islands (Camorta, Katchal, Nancowry and Trinkat). Current Science 89:195–200

Author's personal copy Diversity, Distribution and Vegetative structure of mangroves of the Andaman and Nicobar Islands, India Rao TA, Chakraborti S (1987) Distributional resume of coastal floristic elements in the Andaman and the Nicobar islands. Current Science 56:1045–1051 Rao TA, Sastry ARK (1972) An ecological approach towards classification of Coastal Vegetation of India – I. Strand vegetation. Indian Forester 98:597–607 Ray SK, Acharyya A (2007) 26 December 2004 earthquakes: coseismic vertical ground movement in the Andaman Islands. Geol Surv India Spec Publ 89:63–81 Ray SK, Acharyya A (2011) Coseismic uplift, slow plant mortality and ecological impact in North Andaman following the December 2004 (Mw > 9.2). Current Science 101:218–222 Ricklefs RE, Latham RE (1993) Global patterns of diversity in mangrove floras. Pages 215–229 in RE Ricklefs and D Schluter (eds.), Species Diversity in Ecological Communities: Historical and Geographical Perspectives, University of Chicago Press. Robertson AI, Daniel PA, Dixon P (1991) Mangrove forest structures and productivity in the Fly River estuary, Papua New Guinea. Mar Biol (Berl) 111:147–155. doi:10.1007/BF01986356 Saenger P (2002) Mangrove Ecology, Silviculture and Conservation. Kluwer Academic Publishers, The Netherlands. 360pp. Sahni KC (1958) Mangrove forest in Andaman and Nicobar Islands. Indian Forester 84:544–562 Sampath Kumar V (2005) An overview of mangroves in Andamans and its significance in maintenance of natural ecosystem. In: Proc. National seminar on Reef Ecosystem remediation: SDMRI Research Publication No.9. Suganthi Devadason Marine Research Institute, Tuticorin, India, pp. 200–212 Sankaran R (2005) Impact of the earthquake and the tsunami on the Nicobar Islands, pp. 10–77. In: Kaul, R. & V. Menon (eds.). The Ground Beneath The Waves: Post-tsunami Impact Assessment of Wildlife and Their Habitats in India—Vol. 2 - The Islands. Wildlife Trust of India, New Delhi, 103pp Satyanarayana B, Raman AV, Dehairs F, Kalavati C, Chandramohan P (2002) Mangrove floristics and zonation pattern of Coringa, Kakinada Bay, East coast of India. Wetl Ecol Manag 10:25–39 Sawale A, Thivakaran GA (2013) Structural Characteristics of Mangrove Forest of Kachchh, Gujarat. J Marine Biolog Assoc India 55:5–11 Shannon CE, Weiner W (1963) The Mathematical Theory of Communication. University of Illinois Press, Urbana, USA Simpson EH (1949) Measurment of diversity. Nature 163:688 Singh VP (2003) Biodiversity, community pattern and status of Indian mangroves. Desertification in the Third Millennium Proceedings of an International Conference, Dubai, Edited by Abdulrahman S. Alsharhan, Abdulrahman Fowler, Andrew S. Goudie, Eissa M Abdellatif, and Warren W. Wood Taylor & Francis 2003. 205-216. Singh VP, Garge A (1993) Ecology of Mangrove Swamps of the Andaman Islands. International Book Distributors (Dehradun, India) 181p. Singh VP, Garge A, Pathak SM, Mall LP (1987b) Pattern and process in mangrove forests of the Andaman Islands. Vegetation: pp185 - 188. Singh VP, Mall LP, Garge A, Pathak SM (1986) Some ecological aspects of mangrove forest of Andaman Islands. J. Bombay Nat. Hist. Soc. pp525 - 537. Singh VP, Mall LP, Garge A, Pathak SM (1987a) A new record of some mangrove species from Andaman and Nicobar Islands and their distribution. Indian Forestor. 113:214

Sinha BK (1999) Flora of Great Nicobar Island. Botanical Survey of India, Calcutta Sivakumar K (2007) Impact of the 2004 tsunami on the Vulnerable Nicobar megapode Megapodius nicobariensis. Oryx 44:71–78 Smith TJIII (1992) Forest structure. In: Robertson AI, Alongi DM (eds) Tropical mangrove ecosystems. American Geophysical Union. American Geophysical Union, Washington, pp. 101–136 Spalding M, Kainuma M, Collins L (2010) World Atlas of mangroves. ISME publication.pp 320. Sreekumar PV, Kala N (1998) Critical Notes on Xylocarpus Koen. (Meliaceae) in Andaman and Nicobar Islands. Indian Forester 124: 259–261 Sridhar R, Thangaradjou T, Kannan L, Ramachandran A, Jayakumar S (2006) Rapid assessment on the impact of tsunami on mangrove vegetation of the Great Nicobar Island. Journal of the Indian Society of Remote Sensing 34(1):89–93 Stevens PF (2001) Angiosperm phylogeny website version 9, June 2008. Available: http://www.mobot.org/MOBOT/research/APweb/. Accessed 25 Jul 2009 Thivakaran GA, Saravanakumar A, Serebiah JS, Sunderraj W, Vijaykumar V (2003) Vegetation Structure of Kachchh Mangroves, Gujarat, Northwest Coast of India. Indian J Marine Sci 32:37–44 Thothathri K (1981) Studies on the Mangroves of Peninsular India vs. The Andaman and Nicobar Islands. Bull. Bot. Surv. India. 23:151– 154 Tomlinson PB (1986) The botany of mangroves. Cambridge (Cambridge University Press). Utawale AG, Dwivedi SN, Singbal SYS (1973) Ecology of Mangroves in Mandovi and Zuari Estuaries and the interconnecting Cumbarja Canal of Goa. Indian J. Marine Sci. 2:47–53 Upadhyay VP, Mishra PK, Sahu JR (2007) Vegetation structure and species distribution pattern of mangroves species in Bhitarkanika Ecosystem, Orissa, India. Asian journal of water, Environmental and pollution 5(4):69–76 Upadhyay VP, Mishra PK (2014) An Ecological Analysis of Mangroves Ecosystem of Odisha on the Eastern Coast of India. Proc Indian Natl Sci Acad 80:647–661 van Steenis CGGJ (1957) Outline of vegetation types in Indonesia and some adjacent regions. Proceedings of the 8th Pacific Science Congress, vol. IV: 61–97. van Steenis CGGJ (1958) Ecology of mangroves. Introduction to account of the Rhizophoraceae by Ding Hou, Flora Malesiana, Ser. I, 5:431– 441 Vannucci M (2001) What is so special about mangroves? Braz J Biol 61: 599–603 Wang BS, Liang SC, Zhang WY, Zan QJ (2003) Mangrove flora of the world. Acta Bot Sin 45:644–653 Watson JG (1928) - Mangrove Forests of theMalay Peninsula.Malayan Forest RecordsNo. 6, FederatedMalay States Government, Singapore, 275 pp. White AT, Martosubroto P, Sadorra MSM (ed.’s) (1989) The coastal environmental profile of Segara Anakan-Cilacap, South Java, Indonesia. ICLARM Technical Reports 25, 82 pp. International Center for Living Aquatic Resources Management, Manila, Philippines