Journal of Threatened Taxa | www.threatenedtaxa.org | 26
September 2019 | 11(12): 14518–14526
Seasonal vegetation shift and wetland
dynamics in vulnerable granitic rocky outcrops of Palghat Gap of southern
Western Ghats, Kerala, India
Pathiyil Arabhi
1 & Maya Chandrasekharan Nair
2
1 Environmental
Resources Research Centre (ERRC), NCC Road, P.B. No. 1230, P.O. Peroorkada, Thiruvananthapuram, Kerala 695005, India.
1 Department of
Botany, Baselius College, K.K. Road, Kottayam, Kerala
686001, India.
2 Post Graduate
and Research Department of Botany, Govt. Victoria College (University of
Calicut), College Road, Palakkad, Kerala 678001, India.
1 arabhip1@gmail.com
(corresponding author), 2 drmayadhoni@gmail.com
Abstract:
Low altitude granitic hillock systems prevalent in Palghat (Palakkad) Gap
region of southern Western Ghats were analyzed for
seasonal dynamics in wetland taxa associated with marshy ephemeral flush
vegetation, small ephemeral pools and deep rock pools. Due to characteristic habitat features, such
systems harbor a unique pattern of microhabitats and
associated floristic components. Wet
phase in rocky outcrops in the monsoon season establishes a hydro-geomorphic
habitat that supports establishment of wetland taxa like Eriocaulon,
Drosera, Utricularia, Dopatrium, and Rotala. Seasonal shift in the floral associations was
evident in tune with wetland dynamics.
Wet rocks support ephemeral flush vegetation which display some unique
plant associations of species of Eriocaulon,
Utricularia, Drosera, Cyanotis, Murdannia, and Lindernia.
Small ephemeral pools displayed taxa like Rotala
malampuzhensis R.V. Nair, Dopatrium junceum (Roxb.) Buch.-Ham. ex
Benth., D. nudicaule (Willd.) Benth., Monochoria vaginalis (Burm.f.)
C. Presl, and Cyperus
iria L.
Rocky pools are the habitats of aquatic angiosperms like Nymphaea
nouchali Burm. f., Ludwigia adscendens (L.)
H. Hara, Utricularia aurea
Lour. and Hydrilla verticillata (L.f.) Royle. The study documented 121 plant taxa from
37 families during a wet phase from rocky outcrops of the study area. Gradual shift in vegetation is evident as
water recedes from granitic hillocks.
During the period from December to March, the rocky pools dry up which
results in a shift in the vegetation pattern where Poaceae
members form the dominant elements. As
most of the rocky outcrops are exposed to extreme temperature and acute water
shortage, the taxa inhabiting such ecosystems tend to evolve much faster than
in other habitats. Moreover, the vicinity
of these hillocks in the Palghat Gap region to human settlements, face threats
like fire, grazing, quarrying, dumping of wastes etc. which may cause
considerable loss to the very sensitive plant communities which are not yet
fully documented.
Keywords:
Granitic hillocks, Palakkad, vegetation shift, wetland dynamics.
doi: https://doi.org/10.11609/jott.4732.11.12.14518-14526
Editor: Vijayasankar Raman, University of Mississippi, Mississippi, USA. Date
of publication: 26 September 2019 (online & print)
Manuscript details: #4732 | Received 27 November
2018 | Final received 01 July 2019 | Finally accepted 01 September 2019
Citation: Arabhi, P. & M.C. Nair (2019). Seasonal vegetation shift and wetland dynamics in
vulnerable granitic rocky outcrops of Palghat Gap of southern Western Ghats,
Kerala, India. Journal of Threatened Taxa 11(12): 14518–14526. https://doi.org/10.11609/jott.3891.11.12.14518-14526
Copyright: © Arabhi & Nair 2019. Creative Commons Attribution
4.0 International License. JoTT allows unrestricted use, reproduction, and
distribution of this article in any medium by adequate credit to the author(s)
and the source of publication.
Funding: None.
Competing interests: The authors declare no competing
interests.
Author details: Pathiyil Arabhi is working as Assistant Professor in Department of
Botany, Baselius College, Kottayam. Dr. Maya Chandrasekharan Nair is Assistant
Professor and Head, Post Graduate and Research Department of Botany, Govt.
Victoria College, Palakkad who is specialized in plant taxonomy and floristics.
Author contribution: Both the authors contributed equally in preparation
and compilation of the manuscript.
Acknowledgements: First author is thankful to Director, and staff of
Environmental Resources Research Centre (ERRC), Thiruvananthapuram and
Principal, Baselius College, Kottayam for the support
and encouragement. The second author acknowledges the support from Director,
Collegiate Education, Govt. of Kerala and Principal, Govt. Victoria College,
Palakkad for the facilities and encouragement.
Introduction
Rocky outcrops, which rise abruptly from the
surrounding landscape, have a patchy distribution, and represent centers of diversity and endemism for both animal and plant
life (Hopper & Withers 1997). They
support high levels of species diversity and endemism, have provided stable
micro-climates for thousands of years and also provide important insights into
our ecological past where they contain the remains of extinct species
(Fitzsimons & Michael 2017). They
exhibit extreme climatic and edaphic features strikingly different from the
surrounding environment.
The Palghat Gap, a 32-km break in the hill ranges of
the Western Ghats with an average elevation of 140m, is a peculiar geological
feature in southern India along 10.7500N latitude which divides the
Western Ghats into Nilgiri Hills on the northern lip
and Anamalai-Palani Hills on the southern lip. The gap area is characterized with gneissic, charnockite and amphibolite rock types (Cruz et al.
2000). Small and medium-sized rocky
hillocks are common in the Gap area and most of them are covered with rich
vegetation providing rich grazing areas for cattle. They perform significant ecosystem services,
as the main repositories of water resources keeping the wells of nearby areas
filled. In Kerala, lateritic and
granitic hillocks occur with a prevalence of lateritic ones in northern and
granitic hillocks in southern Kerala.
Numerous low-altitude hillock systems which are characteristic to the
Palghat Gap region of southern Western Ghats have their own unique
manifestations of floral elements due to spatial and ecological isolation from
the surrounding vegetation. These
granitic outcrops provide suitable microhabitats for many rare and endemic
plants. Floristic explorations on such
low-altitude hillocks resulted in the discoveries of taxa new to science (Jose
et al. 2013, 2015).
Low-altitude hillock systems exhibit seasonal wetland
dynamics and periodical shifts in vegetation patterns in response to the onset
and retreat of the monsoons. The wet
phase in such hillock systems is characterized by unique associations of
ephemeral herbaceous floral elements in specific microhabitats like seasonal
pools (Pramod et al. 2014). Most of the
hillocks in the Palghat Gap region are found in the neighborhood
of human settlements and are facing various threats, including fire, grazing,
quarrying and dumping of wastes, which cause considerable loss to the very
sensitive plant communities which are not yet fully documented. With this background, the present paper
summarizes the floristic diversity of ephemerals associated with the
microhabitats of granitic hillocks in the Palghat Gap of southern Western
Ghats.
Materials and Methods
Study Area
Documentation of wetland taxa in selected granitic
hillocks of seven different forest ranges, viz., Alathur,
Kollengode, Nelliyampathy, Olavakkode, Ottappalam, Walayar, and Mannarkkad was
carried out between June 2016 and May 2018.
The sampling locations lie between 10.551–11.010 0N and
76.161–76.828 0E (Image 1).
The plants were collected and identified using regional floras along
with reference to local herbaria MH and CALI and enumerated based on APG IV
(Chase et al. 2016). The
nomenclature validation was carried out using IPNI (www.ipni.org), The Plant
List (www.theplantlist.org) databases and Flowering Plants of Kerala (Sasidharan 2014).
The plant diversity in different microhabitats during the wet phase were
identified (Sreejith et al. 2016), documented and seasonal vegetation
shift was observed. The threat
assessment of the taxa was based on IUCN (2019) guidelines. The plants and habitats were photographed using
digital cameras Nikon D 3200 and Sony Cyber shot DSC HX7V.
Results and Discussion
Granitic hillock systems harbor
unique microhabitats and associated floristic components. Seasonal shift in vegetation was apparent,
which shows demarcating wet and dry phases based on the availability of
moisture. The micro environment on the
rock surface in these hillock systems varied between extremely hot and arid in
dry seasons to water logged and slippery in the wet season. Microhabitat conditions present on the
outcrops vary significantly from the adjoining areas and hence they can be
referred to as terrestrial habitat islands.
Wet phase in granitic hillocks
The
establishment of the wet phase in the rocky outcrops begins with the onset of
the southwest monsoon and ends with the completion of the northeast
monsoon. Occurrence of the wet phase in
rocky outcrops in the form of different microhabitats in the monsoon season
(June–November) establishes hydro-geomorphic habitats with significant
microhabitats and floral associations (Image 2).
Ephemeral
flush vegetation (EFV): This is the
predominant vegetation type occurring in the microhabitats of granitic hillocks
during the wet phase. The ephemeral
herbaceous plants flourish in the open rocky slopes through which water flows
slowly. This microhabitat harbors 11 species, viz., Burmannia
coelestis D. Don, Cyanotis
papilionacea (Burm. f.)
Schult. & Schult. f.,
Drosera indica
L., D. burmanni Vahl,
Eriocaulon pectinatum
Ruhland, E. thwaitesii
Körn., E. xeranthemum Mart., Lindernia ciliata (Colsm.) Pennell, Murdannia
semiteres (Dalzell) Santapau,
Utricularia lazulina
P. Taylor, and U. graminifolia Vahl; and of these, species of Utricularia
are exclusive EFV endemics and the insectivorous taxa which prefer nutrient
deficient soil, viz., Drosera spp. and Utricularia spp., were found to be well
adapted to this habitat. This
micro-eco-climate showed unique plant associations between Eriocaulon-Utricularia-Drosera
and Lindernia.
Small
ephemeral pools (SEP): Most of the
rocky outcrops possess several shallow depressions which remain filled with
water during the rainy season. They form
unique microhabitats for some wet phase elements, such as, Dopatrium
junceum (Roxb.)
Buch.-Ham. ex Benth., D. nudicaule
(Willd.) Benth., Rotala indica (Willd.) Koehne, R. malampuzhensis R. V. Nair, Monochoria
vaginalis (Burm. f.) C. Presl,
and Cyperus iria L. The study recorded 20 species (Table 1) from
this microhabitat and the above six taxa were specifically confined to this
microhabitat.
Rock pools
(RP): Some hillocks possess deep
water-filled pools mainly created as a result of quarrying which harbor aquatic taxa like Nymphaea nouchali
Burm.f., Hydrilla verticillata (L.f.) Royle, Ludwigia adscendens (L.) H.
Hara, Utricularia aurea
Lour., Ipomoea aquatica Forssk., Marsilea quadrifolia L., and Rotala
mexicana Schltdl. &
Cham. This unique ecosystem recorded
eight species, of which the first four members were recorded from this
microhabitat only.
Exposed rock
surfaces (ERS): These are flat or irregular rocky surfaces
which were directly exposed to sunlight.
These areas with poor soil deposition remain more or less wet during the
rainy season. This survey recorded 35
taxa from this microhabitat, viz., Burmannia coelestis D.Don, Centranthera indica
(L.) Gamble, Geissaspis cristata Wight & Arn.,
and Lobelia alsinoides Lam., of which Xyris pauciflora Willd. was recorded specifically from this microhabitat.
Rocky
crevices and fissures (RCF): Granitic
outcrops possess several rock crevices and fissures with very thin soil
deposition which act as ecological niche for some specific species like Henckelia incana (Vahl) Spreng. and Cyanotis arachnoidea C.B.
Clarke, and about 14 species were recorded from this microhabitat and the above
mentioned taxa were specifically confined to this habitat.
Soil-filled
depressions (SFD): Rocky
outcrops possess several depressions which accumulate water and soil during the
rainy season and provide a marshy habitat.
Around 81 species were recorded from this particular microhabitat of
which Alysicarpus monilifer
(L.) DC., Isoetes coromandeliana
L.f., Crotalaria linifolia
L.f., Cyanotis burmanniana Wight, Ophioglossum
nudicaule L.f., Lindernia anagallis (Burm.f.) Pennell, Ludwigia hyssopifolia (G.Don) Exell, Mitrasacme pygmaea R.Br., etc. were some species found
exclusively in this microhabitat.
Soil rich
area (SRA): These microhabitats with good soil
deposition having more than 20cm soil thickness, during the wet phase were
frequently occupied by species like Chrysopogon
aciculatus (Retz.) Trin,
Cyanotis cristata
(L.) D.Don, Eclipta
prostrata (L.) L., Spermacoce articularis L.f., Spermacoce hispida
L., Spermacoce alata Aubl., Commelina clavata C.B. Clarke, Commelina
diffusa Burm.f., Eragrostis unioloides (Retz.)
Nees ex Steud., and Spermacoce ocymoides Burm.f. Among them,
the first six taxa were exclusively found in this microhabitat.
Boulders (B):
These microhabitats consist of
isolated rocks or large rocks in groups which were found to be inhabited with
some mosses, pteridophytes like Cheilanthes
opposita Kaulf., Parahemionitis cordata
(Hook. & Grev.) Fraser-Jenk.
and angiosperms like Bulbostylis barbata (Rottb.) C.B. Clarke,
Osbeckia muralis
Naudin, and Oxalis corniculata
L. during the wet phase.
During the study 121 plant species belonging to 37
families (Table 1) were documented from different microhabitats in the wet
phase (June–November). The most
represented family were Fabaceae with 22 species followed by Cyperaceae with 16 species and Commelinaceae
with 10 species.
Dry phase in granitic hillocks
A gradual shift
in vegetation was evident as water receded from granitic hillocks after the
retreat of the monsoon. During the
period from December to April, the small ephemeral pools dry up, ephemeral
flush vegetation disappears, water level in deep rock pools lowers, which
results in a shift in wet vegetation to a drought-adaptive taxa. Dry phase is characterized by the complete
absence of microhabitats like EFV and SEP and shift in plant associations in
other microhabitats like ERS, RCF, SFD and SRA (Image 3).
During the dry
phase, plant species like Heliotropium marifolium J. Koenig ex Retz. and Cleome
aspera J. Koenig ex DC. dominate in exposed rock surfaces (ERS) and
rock crevices and fissures (RCF) harbors plant taxa
like Anisochilus carnosus (L.f.) Wall., Andrographis echioides (L.) Nees, Cleome
viscosa L., Dimeria
deccanensis Bor, Hyptis suaveolens (L.)
Poit., and Theriophonum fischeri Sivad. Plant species like Perotis
indica (L.) Kuntze, Croton
hirtus L’Hér.,
Ischaemum rugosum Salisb., Rhynchosia rufescens (Willd.) DC., Blumea virens DC.,
Richardia scabra L., Tephrosia
villosa (L.) Pers., Merremia
tridentata (L.) Hallier
f., and Apluda mutica
L. were mostly seen in soil-filled depressions (SFD) during the dry
phase. Soil rich area (SRA) is dominated
by plant taxa such as Alternanthera bettzickiana (Regel)
G. Nicholson, Achyranthes aspera L., Acalypha alnifolia
Klein ex Willd., Sesamum
radiatum Schumach.
& Thonn., Sida
cordata (Burm.f.) Borss. Waalk., Boerhavia diffusa L.,
Ipomoea pes-tigridis L., grasses like Heteropogon contortus (L.)
P. Beauv. ex Roem. & Schult., Arundinella
mesophylla Nees ex Steud., and Garnotia tenella (Arn. ex Miq.) Janowski during the dry
phase. During the dry phase, the mosses
and pteridophytes inhabited on boulders (B) dry up.
Both dry and wet phases in granitic outcrops share
floristic elements of scrub jungles and tree cover and such vegetation provides
isolated patches of greenery to these vulnerable habitats.
Scrub jungle elements
Some shrubs and climbers give a stunted forest
appearance to the rocky hillocks. Ziziphus jujuba Mill., Z. oenopolia
(L.) Mill., Canthium coromandelicum
(Burm.f.) Alston, C. rheedei
DC., Euphorbia trigona Mill., Flacourtia indica (Burm.f.) Merr., Ehretia microphylla Lam.,
Catunaregam spinosa (Thunb.) Tirveng., Casearia esculenta Roxb.,
C. wynadensis Bedd.,
Abrus precatorius L.,
Getonia floribunda Roxb.,
Pterolobium hexapetalum
(Roth) Santapau & Wagh,
and Spatholobus parviflorus
(DC.) Kuntze. are some of the common scrub jungle
elements found in rocky systems.
Tree cover
The extent of tree cover varies in different hillock
systems from thick tree cover and associated shade loving shrub elements to
hillock systems with sparsely distributed tree species. This study documented 100 tree taxa from
rocky hillocks and among them, Cochlospermum religiosum (L.) Alston, Givotia
moluccana (L.) Sreem., Firmiana simplex (L.) W. Wight, Phyllanthus
emblica L., Strychnos
nux-vomica L., S. potatorum
L.f., Morinda pubescens Sm., Azadirachta
indica A. Juss., Holarrhena pubescens
Wall. ex G. Don, Cleistanthus collinus (Roxb.) Benth. ex Hook.f., Wrightia tinctoria
R.Br., Ficus exasperata
Vahl, Pterocarpus
marsupium Roxb., and Terminalia paniculata Roth. were common inhabitants of most of the
rocky hillocks.
Threatened Taxa with conservation significance
The vulnerable habitats of granitic rocky outcrops of
the Palghat Gap of the southern Western Ghats harbor
taxa with conservation significance. The
analysis revealed the presence of five taxa under threatened category (IUCN
2019). Pterocarpus
marsupium Roxb. among tree cover element is
classified as Near Threatened and Cleistanthus
collinus (Roxb.) Benth. ex Hook.f. and Santalum album L. are Vulnerable. The wet phase taxon, Eriocaulon
pectinatum Ruhland and
scrub jungle element, Casearia wynadensis
Bedd. are also classified as Vulnerable as per IUCN
Red List of Threatened Plants version 2019-2 (IUCN 2019). Conservation status of about 45% wetland taxa
recorded from the study area are not yet assessed and as the habitats of these
elements are facing serious threats, the future of these taxa inhabiting these
niche is uncertain.
Threats to low altitude hillocks in Palghat Gap region
Rapid urbanization places anthropogenic pressures on
low altitude granitic hillocks in the Gap region of the southern Western
Ghats. Indiscriminate quarrying poses
serious threats to the unique flora and fauna on the granitic hillocks. Some of the low altitude hillocks on either
side of the national highways were destroyed for expansion of the highway. The hillocks near human settlements have
become dumping grounds for disposal of wastes which adversely affects the soil
quality and vegetation. Invasion of Chromolaena odorata (L.)
R.M. King & H. Rob. and Mimosa diplotricha Sauvalle and promotion of monoculture plantations of Tectona and Acacia were found to retard the
growth of indigenous flora of the hillocks.
During the dry phase, most of the rocky outcrops were dominated by
fire-indicating taxa like Hyptis suaveolens (L.) Poit. and
grasses like Apluda mutica
L. which easily catch fire and lead to the loss of natural vegetation. Some of these hillocks are susceptible to
landslides owing to indiscriminate quarrying which in turn destroy entire flora
and fauna of associated microhabitats.
Conclusions
All microhabitat categorizations are limited by
factors such as soil depth, water content and other seasonal variations and
there is no clear physical demarcation between the habitats. The onset of the monsoon season leads to
dispersion of water in soil-filled depressions or even flat surfaces and hence
overlay in species composition can be observed in these habitats. While some taxa were restricted to a single
microhabitat, other species were able to grow in an array of closely similar
microhabitats although their dominance levels varied with reference to specific
habitat inclinations and niche.
The documentation of taxa during the wet phase alone
could record 121 elements belonging to 37 families distributed in eight
different microhabitats which are ephemeral and seasonal. The adaptive strategies provided by such
microhabitats support taxa which have narrow ecological amplitude and share
narrow ecological niches. Hence
conservation of such microhabitats becomes inevitable as far as these
vulnerable habitats are concerned as they are prone to many human-induced
threats along with biological invasions.
Natural calamities such as landslides and forest fires and anthropogenic
activities including quarrying and urbanization reduce the natural vegetation
of these unique habitats. Hence,
conservation strategies have to be formulated for the maintenance of floristic
diversity in these unique ecosystems.
Table 1. Distribution of wet phase floristic elements
in different microhabitats.
|
Botanical
name |
Family |
Micro-habitats |
1 |
Aeschynomene indica L. |
Fabaceae |
SEP, SFD |
2 |
Alysicarpus bupleurifolius
(L.) DC. |
Fabaceae |
SFD |
3 |
Alysicarpus heterophyllus
(Baker) Jafri & Ali |
Fabaceae |
SFD |
4 |
Alysicarpus monilifer (L.) DC. |
Fabaceae |
SFD |
5 |
Alysicarpus
vaginalis (L.) DC. |
Fabaceae |
ERS, SFD |
6 |
Bulbostylis barbata (Rottb.)
C.B.Clarke |
Cyperaceae |
B, ERS, RCF |
7 |
Bulbostylis puberula Kunth |
Cyperaceae |
SEP, RCF |
8 |
Burmannia coelestis D.Don |
Burmanniaceae |
ERS, EFV |
9 |
Centranthera indica (L.) Gamble |
Orobanchaceae |
ERS, SFD |
10 |
Centranthera tranquebarica (Spreng.) Merr. |
Orobanchaceae |
SEP, SFD |
11 |
Chamaecrista absus (L.) H.S.Irwin
& Barneby |
Fabaceae |
SFD, SRA |
12 |
Chamaecrista kleinii (Wight & Arn.) V.Singh |
Fabaceae |
SFD |
13 |
Chamaecrista mimosoides (L.) Greene |
Fabaceae |
ERS, SFD |
14 |
Chamaecrista nictitans subsp. patellaria
(Collad.) H.S.Irwin &
Barneby |
Fabaceae |
ERS, SFD |
15 |
Cheilanthes opposita Kaulf. |
Pteridaceae |
B |
16 |
Chrysopogon aciculatus (Retz.) Trin. |
Poaceae |
SRA |
17 |
Commelina clavata C.B.Clarke |
Commelinaceae |
SFD, SRA |
18 |
Commelina diffusa Burm.f. |
Commelinaceae |
SFD, SRA |
19 |
Commelina wightii Raizada |
Commelinaceae |
ERS, SFD |
20 |
Crotalaria
linifolia L.f. |
Fabaceae |
SFD |
21 |
Crotalaria
nana Burm.f. |
Fabaceae |
SFD |
22 |
Cyanotis arachnoidea C.B.Clarke |
Commelinaceae |
RCF |
23 |
Cyanotis axillaris (L.) D.Don
ex Sweet |
Commelinaceae |
ERS, SEP |
24 |
Cyanotis burmanniana Wight |
Commelinaceae |
SFD |
25 |
Cyanotis cristata (L.) D.Don |
Commelinaceae |
SRA |
26 |
Cyanotis papilionacea (Burm.f.)
Schult. & Schult.f. |
Commelinaceae |
EFV, ERS, RCF |
27 |
Cyperus clarkei T.Cooke |
Cyperaceae |
SFD |
28 |
Cyperus compressus L. |
Cyperaceae |
SFD |
29 |
Cyperus cyperinus (Retz.) Suringar |
Cyperaceae |
SFD |
30 |
Cyperus dubius Rottb. |
Cyperaceae |
SFD |
31 |
Cyperus iria L. |
Cyperaceae |
SEP |
32 |
Cyperus maderaspatanus Willd. |
Cyperaceae |
ERS, RCF |
33 |
Cyperus rotundus L. |
Cyperaceae |
SFD |
34 |
Desmodium triflorum (L.) DC. |
Fabaceae |
ERS, SFD |
35 |
Dipcadi montanum (Dalzell) Baker |
Asparagaceae |
SFD |
36 |
Dopatrium junceum (Roxb.)
Buch.-Ham. ex Benth. |
Plantaginaceae |
SEP |
37 |
Dopatrium nudicaule (Willd.)
Benth. |
Plantaginaceae |
SEP |
38 |
Drosera burmanni Vahl |
Droseraceae |
ERS, EFV |
39 |
Drosera indica L. |
Droseraceae |
ERS, EFV |
40 |
Eclipta prostrata (L.)L. |
Asteraceae |
SRA |
41 |
Eragrostis unioloides (Retz.) Nees ex Steud. |
Poaceae |
ERS, SFD, SRA |
42 |
Eriocaulon pectinatum Ruhland |
Eriocaulaceae |
EFV, ERS |
43 |
Eriocaulon thwaitesii Körn. |
Eriocaulaceae |
EFV, ERS |
44 |
Eriocaulon
xeranthemum Mart. |
Eriocaulaceae |
EFV, ERS |
45 |
Fimbristylis aestivalis Vahl |
Cyperaceae |
RCF, SFD |
46 |
Fimbristylis argentea (Rottb.)
Vahl |
Cyperaceae |
SFD |
47 |
Fimbristylis
falcata (Vahl) Kunth |
Cyperaceae |
SFD |
48 |
Fimbristylis littoralis Gaudich. |
Cyperaceae |
SFD |
49 |
Fimbristylis microcarya F.Muell. |
Cyperaceae |
SFD, SEP |
50 |
Fimbristylis polytrichoides (Retz.)
Vahl |
Cyperaceae |
RCF, SFD |
51 |
Fimbristylis schoenoides (Retz.) Vahl |
Cyperaceae |
SEP, SFD |
52 |
Geissaspis cristata Wight & Arn. |
Fabaceae |
ERS, SFD |
53 |
Geissaspis tenella Benth. |
Fabaceae |
ERS, SFD |
54 |
Glinus oppositifolius
(L.) Aug.DC. |
Molluginaceae |
SFD |
55 |
Henckelia incana (Vahl)
Spreng. |
Gesneriaceae |
RCF |
56 |
Hoppea fastigiata (Griseb.)
C.B.Clarke |
Gentianaceae |
ERS, SFD |
57 |
Hydrilla verticillata (L.f.) Royle |
Hydrocharitaceae |
RP |
58 |
Hygrophila ringens (L.)
R.Br. ex Spreng. |
Acanthaceae |
SFD |
59 |
Indigofera uniflora Roxb. |
Fabaceae |
ERS, SFD |
60 |
Ipomoea
aquatica Forssk. |
Convolvulaceae |
SEP, RP |
61 |
Ipomoea marginata (Desr.)
Verdc. |
Convolvulaceae |
SFD, SEP |
62 |
Isoetes coromandeliana L.f. |
Isoetaceae |
SFD |
63 |
Limnophila aromatica (Lam.) Merr. |
Plantaginaceae |
SEP, SFD |
64 |
Limnophila heterophylla (Roxb.)
Benth. |
Plantaginaceae |
SEP, SFD |
65 |
Lindernia anagallis (Burm.f.)
Pennell |
Linderniaceae |
SFD |
66 |
Lindernia antipoda (L.) Alston |
Linderniaceae |
SFD |
67 |
Lindernia caespitosa (Blume) Panigrahi |
Linderniaceae |
SFD |
68 |
Lindernia ciliata (Colsm.)
Pennell |
Linderniaceae |
EFV, ERS, SFD |
69 |
Lindernia
crustacea (L.) F.Muell. |
Linderniaceae |
SFD |
70 |
Lindernia hyssopioides (L.) Haines |
Linderniaceae |
SFD |
71 |
Lindernia nummulariifolia (D.Don) Wettst. |
Linderniaceae |
SFD, SEP |
72 |
Lindernia rotundifolia (L.) Alston |
Linderniaceae |
SFD, SEP |
73 |
Lobelia
alsinoides
Lam. |
Campanulaceae |
ERS, SFD |
74 |
Ludwigia adscendens (L.) H.Hara |
Onagraceae |
RP |
75 |
Ludwigia hyssopifolia (G.Don)
Exell |
Onagraceae |
SFD |
76 |
Marsilea quadrifolia L. |
Marsileaceae |
SEP, RP |
77 |
Melochia corchorifolia L. |
Malvaceae |
SFD, SRA |
78 |
Microcarpaea
minima (K.D.Koenig ex
Retz.) Merr. |
Plantaginaceae |
SFD |
79 |
Mitrasacme indica Wight |
Loganiacaeae |
SFD |
80 |
Mitrasacme pygmaea R.Br. |
Loganiacaeae |
SFD |
81 |
Monochoria
vaginalis (Burm.f.) C.Presl |
Pontederiaceae |
SEP |
82 |
Murdannia semiteres (Dalzell) Santapau |
Commelinaceae |
EFV, ERS |
83 |
Murdannia spirata (L.) G.Brückn. |
Commelinaceae |
SFD |
84 |
Nymphaea
nouchali Burm.f. |
Nymphaeaceae |
RP |
85 |
Oldenlandia corymbosa L. |
Rubiaceae |
SFD, RCF |
86 |
Oldenlandia diffusa (Willd.)
Roxb. |
Rubiaceae |
SFD |
87 |
Oldenlandia dineshii Sojan
& Suresh |
Rubiaceae |
ERS, SFD |
88 |
Ophioglossum nudicaule L.f. |
Ophioglossaceae |
SFD |
89 |
Oryza
rufipogon
Griff. |
Poaceae |
SFD |
90 |
Osbeckia muralis Naudin |
Melastomataceae |
B, ERS, RCF, SFD |
91 |
Oxalis
corniculata L. |
Oxalidaceae |
B, SFD |
92 |
Pandanus
canaranus Warb. |
Pandanaceae |
RP |
93 |
Parahemionitis cordata (Hook. & Grev.)
Fraser-Jenk. |
Pteridaceae |
B |
94 |
Parasopubia delphiniifolia
(L.) H.-P.Hofm. & Eb.Fisch. |
Orobanchaceae |
ERS, SFD |
95 |
Polygala
chinensis L. |
Polygalaceae |
SFD |
96 |
Polygala
persicariifolia
DC. |
Polygalaceae |
ERS, RCF |
97 |
Rhamphicarpa fistulosa (Hochst.)
Benth. |
Orobanchaceae |
ERS, SFD |
98 |
Rhynchosia rufescens (Willd.)
DC. |
Fabaceae |
RCF, SFD |
99 |
Rhynchosia suaveolens (L.f.)
DC. |
Fabaceae |
RCF, SFD |
100 |
Rotala indica (Willd.)
Koehne |
Lythraceae |
SEP |
101 |
Rotala malampuzhensis R.VNair |
Lythraceae |
SEP |
102 |
Rotala mexicana Schltdl.
& Cham. |
Lythraceae |
SEP, RP |
103 |
Sesamum prostratum Retz. |
Pedaliaceae |
ERS, SFD |
104 |
Setaria pumila (Poir.)
Roem. & Schult. |
Poaceae |
SFD, SRA |
105 |
Sida acuta Burm.f. |
Malvaceae |
SFD, SRA |
106 |
Smithia blanda Wall. |
Fabaceae |
SFD |
107 |
Smithia conferta Sm. |
Fabaceae |
SFD |
108 |
Spermacoce alata Aubl. |
Rubiaceae |
SRA |
109 |
Spermacoce articularis L.f. |
Rubiaceae |
SRA |
110 |
Spermacoce hispida L. |
Rubiaceae |
SRA |
111 |
Spermacoce ocymoides Burm.f. |
Rubiaceae |
SFD, SRA |
112 |
Spermacoce pusilla Wall. |
Rubiaceae |
RCF, SFD |
113 |
Striga
angustifolia (D.Don) C.J.
Saldanha |
Orobanchaceae |
ERS, SFD |
114 |
Striga asiatica (L.) Kuntze |
Orobanchaceae |
ERS, SFD |
115 |
Tephrosia
maxima (L.) Pers. |
Fabaceae |
SFD, SRA |
116 |
Tephrosia purpurea (L.) Pers. |
Fabaceae |
ERS, SFD, SRA |
117 |
Utricularia aurea Lour. |
Lentibulariaceae |
RP |
118 |
Utricularia lazulina P.Taylor |
Lentibulariaceae |
EFV |
119 |
Utricularia graminifolia Vahl |
Lentibulariaceae |
EFV |
120 |
Xyris pauciflora Willd. |
Xyridaceae |
ERS |
121 |
Zornia
gibbosa
Span. |
Fabaceae |
ERS, SFD |
EFV—Ephemeral flush vegetation | SEP—Small ephemeral
pool | RP—Rock pool | ERS—Exposed rock surface | RCF—Rocky crevice and fissure
| SFD—Soil-filled depression | SRA—Soil rich area | B—Boulder.
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