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Lake 2010: Wetlands, Biodiversity and Climate Change 22 nd -24 th December 2010 Page 1 LAST ABODES OF RELIC SPECIES IN UTTARA KANNADA-SACRED GROVES AND THEIR SILENT EXTINCTION G.R. Rao, G. Krishnakumar, M.D. Subash Chandran, T.V. Ramachandra Energy and Wetlands Research Group, Centre for Ecological Sciences, Indian Institute of Science (IISc), Bangalore-12 Abstract: Uttara Kannada once known for huge track of evergreen to semievergreen forests has been mercilessly exploited since age of British raj and is still carried over until now. What we have been left with is highly fragmented secondary forests in coastal and easily accessible lowland areas, encountering some good forest patches only in hilly inaccessible areas. In midst of these human modified landscapes are the rare paradises (Sacred groves or Kans) hosting even rarer endemic and endangered species called ‘Relic’ species more or less absent outside these Kans. As seen from the Important value Index (IVI), endangered, emergent trees such as Dipterocarpus indicus growing to height of 40 m or more dominated many transects such as Karikan (117.61), Kathlekan (40.82), Ambepal (21.70), and Attigodu (18.06). Many other relic species dominating the Kan or relic forests include poeciloneuron indicum in Karni (71.96) and Yadanal (27.47), Vateria indica in Nilvase (68.26), Syzygium travancoricum (33.51) in Kathlekan, and Myristica fatua in Kathlekan swamp (15.18). Evergreen percentage was highest for relic localities with 90 and above while the non relic forests had lower evergreen percentage. Endemic percentage was highest for all the relic transects with highest being for Karikan sacred grove (75.53). Though many of the Non-relic transects such as Talekere showed higher endemism than other relic-transects, these endemic species were mostly commoner endemics such as Hopea ponga, Knema attenuate which were found throughout the Western Ghats. Non-relic forests were less in all aspects of diversity, evergreenness and endemism compared to Relic forests. Relic forests had a total of 47 endemic species compared to only 26 species in Non-relic transects. But the real factor of importance for sacred forests emerge in the number of critically endangered, and rarer endemics (termed as ‘Relic species’) it harbor, and are the last abodes of habitats for these species. Introduction The Western Ghats of the Indian peninsula constitute one of the 34 global biodiversity hotspots along with Sri Lanka, on account of its exceptional levels of plant endemism and by serious levels of habitat

G.R. Rao, G. Krishnakumar, M.D. Subash Chandran, T.V. …wgbis.ces.iisc.ernet.in/energy/lake2010/Theme 2/rao_gr.pdf · 2011. 2. 22. · G.R. Rao, G. Krishnakumar, M.D. Subash Chandran,

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  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 1

    LAST ABODES OF RELIC SPECIES IN UTTARA KANNADA-SACRED GROVES

    AND THEIR SILENT EXTINCTION

    G.R. Rao, G. Krishnakumar, M.D. Subash Chandran, T.V. Ramachandra

    Energy and Wetlands Research Group, Centre for Ecological Sciences,

    Indian Institute of Science (IISc), Bangalore-12

    Abstract: Uttara Kannada once known for huge track of evergreen to semievergreen forests has been

    mercilessly exploited since age of British raj and is still carried over until now. What we have been

    left with is highly fragmented secondary forests in coastal and easily accessible lowland areas,

    encountering some good forest patches only in hilly inaccessible areas. In midst of these human

    modified landscapes are the rare paradises (Sacred groves or Kans) hosting even rarer endemic and

    endangered species called ‘Relic’ species more or less absent outside these Kans. As seen from the

    Important value Index (IVI), endangered, emergent trees such as Dipterocarpus indicus growing to

    height of 40 m or more dominated many transects such as Karikan (117.61), Kathlekan (40.82),

    Ambepal (21.70), and Attigodu (18.06). Many other relic species dominating the Kan or relic forests

    include poeciloneuron indicum in Karni (71.96) and Yadanal (27.47), Vateria indica in Nilvase

    (68.26), Syzygium travancoricum (33.51) in Kathlekan, and Myristica fatua in Kathlekan swamp

    (15.18). Evergreen percentage was highest for relic localities with 90 and above while the non relic

    forests had lower evergreen percentage. Endemic percentage was highest for all the relic transects

    with highest being for Karikan sacred grove (75.53). Though many of the Non-relic transects such as

    Talekere showed higher endemism than other relic-transects, these endemic species were mostly

    commoner endemics such as Hopea ponga, Knema attenuate which were found throughout the

    Western Ghats. Non-relic forests were less in all aspects of diversity, evergreenness and endemism

    compared to Relic forests. Relic forests had a total of 47 endemic species compared to only 26

    species in Non-relic transects. But the real factor of importance for sacred forests emerge in the

    number of critically endangered, and rarer endemics (termed as ‘Relic species’) it harbor, and are the

    last abodes of habitats for these species.

    Introduction

    The Western Ghats of the Indian peninsula constitute one of the 34 global biodiversity hotspots along

    with Sri Lanka, on account of its exceptional levels of plant endemism and by serious levels of habitat

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 2

    loss (Conservation International 2005)12,4,6. These chain of hills running for about 1600 km along

    with the west coast (lat.80 and 210 N and long. 730 and 780 E) covers a total geographical area of

    160,000 km2. These hills which harbor extensive tropical forests, also figures on the tropical

    deforestation map of India. In midst of these highly fragmented forests and other man made

    landscapes, sacred groves present an interesting example of forest conservation in the Western Ghats.

    Hughes and Subhash Chandran (1998)5 define ‘sacred groves’ as segments of landscape containing

    trees and other forms of life and geographical features, that are delimited and protected by human

    societies believing that preserving such a patch of vegetation in a relatively undisturbed state is

    necessary for expressing one’s relation to the divine or to nature. So these remain as isolated patches

    of forests in the midst of agricultural landscapes. Sacred places have long and diverse histories in

    human cultures and demonstrate ancient links between peoples and their environments. They are a

    universal phenomenon not associated with any specific religion or world view, but they have a strong

    religious context and are influenced by traditional local beliefs1. These groves harbor rich biodiversity

    and play a significant role in the conservation of biodiversity. The biological resources make indirect

    contributions to the welfare and stability of the local environment. Their plant wealth and

    conservation potential were impressive enough to acknowledge them as ‘mini biosphere reserves’3.

    However, the surveys are largely limited to enumeration of plants only, neglecting analytical studies

    essential for understanding the present status of vegetation needed for evolving suitable strategies for

    their conservation.

    Objectives

    To study the

    • Floristic composition in sacred groves and other protected forests.

    • Qualitative and Quantitative studies of tree vegetation structure in different Kan of Relic

    forests compared to their surrounding forests.

    • Threats on sacred groves and their conservation strategies.

    Study area

    A total of 10 Kan or Relic transects were selected and another 10 from surrounding forests (Non-

    Relic(Kan)) were selected from Uttara Kannada district of Karnataka State and part of Shimoga

    district (table 1 and 2). Uttara Kannada district lies between 740 9’ to 750 10’ east longitude and 130

    55’ to 150 31’ north latitude and extends over an area of 10,327 sq km. It is one of the two coastal

    districts of the state and stretches itself along the coastline of the Arabian sea. It extends to about 328

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 3

    km north-south and about 160 km east-west. It is the richest forest districts of Karnataka, endowed

    with a bountiful variety of fauna and flora.

    Uttara Kannada and Shimoga district harbors following important type of forests.

    1. Evergreen forests

    2. Semievergreen forests

    3. Moist deciduous forests

    4. Dry deciduous forests

    5. Scrub-Savannah and thorny forests

    The evergreen forests are found in places where the rainfall is more than 225 cm and form a narrow

    strip along the Western Ghats. These forests harbor more soft wooded trees. The soil types of these

    evergreen forests are mostly lateritic, but along the river basin it is alluvial. The moist deciduous

    forests are situated in the rainfall areas of 100 cm and more. These forests are rich in timber trees. In

    areas where the rainfall is below 90 cm, the dry deciduous forests are found. The scrub and thorny

    forests are found in places where the rainfall is below 60 cm.

    Sl Relic or Sacred forests District 1 Ambepal-2 Uttara Kannada 2 Attigodu-2 Shimoga

    3 Hessige-2 Shimoga 4 Karikan-lower slope Uttara Kannada 5 Karini Shimoga 6 Kathalekan-G8-swp with S.trav Uttara Kannada 7 Kathalekan-obove settlement Uttara Kannada 8 Niluvase Shimoga 9 Hadgeri-1 Uttara Kannada 10 Yadanal Shimoga

    Table 1: Relic study localities

    Study localities for Non-relic or Surrounding forests

    Sl Surrounding forests District 1 Atvadi Shimoga 2 Belamakki Shimoga 3 Chikmathur Shimoga

    4 Gundbala Uttara Kannada 5 Halki-2 Shimoga 6 Hongodu Shimoga 7 Joginmath-1-sidapur Uttara Kannada

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 4

    8 Kagarasu-mugimane Shimoga 9 Salkodu-5 Shimoga

    10 Talekere-Sidapur Uttara Kannada

    Table 2: Non-Relic study localities

    Materials and Method

    For this study, transect with a total length of 180 m with 5 quadrats each consisting of alternate 20 x

    20 m quadrats was used. In each quadrat all the trees at or above 10 cms DBH (>30 cms GBH) were

    enumerated at 1.3 m height, identified, or samples collected (whenever possible) if field identification

    was not possible and were pressed for herbaria for future identification. Other features like epiphytes,

    climbers, parasites, any disturbances like lopping, logging etc., were also noted. Canopy cover was

    noted and ground litter quantity was weighed. General information such as ground control points

    using a Global Positioning System (GPS), name of the locality, range, human activities such as

    lopping, logging, NTFP, fuel and litter collections, fire incidence, grazing etc. were noted down.

    Results and Discussion

    Floristic composition

    A total of 108 tree species from 32 families were noted from relic transects and 101 species from 42

    families were noted from Non-relic forests. Families with highest species number in relic forests were

    Lauraceae with 10 species followed by Euphorbiaceae, and Ebenaceae, with 9 species each (figure 1

    and 2).

    Relic transects family species no.

    2

    3

    3

    3

    34

    45

    6

    66

    77

    99

    10

    Celastraceae

    Annonaceae

    Dipterocarpaceae

    Flacourtiaceae

    Sterculiaceae

    Meliaceae

    Sapotaceae

    Myristicaceae

    Clusiaceae

    Moraceae

    Rubiaceae

    Anacardiaceae

    Myrtaceae

    Ebenaceae

    Euphorbiaceae

    Lauraceae

    Figure 1: Family species richness in Relic transects

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 5

    Non-relic transects family species no.

    2

    2

    3

    3

    3

    3

    4

    4

    4

    4

    5

    6

    6

    7

    8

    Apocynaceae

    Bignoniaceae

    Combretaceae

    Meliaceae

    Sapotaceae

    Sterculiaceae

    Clusiaceae

    Flacourtiaceae

    Myristicaceae

    Rubiaceae

    Moraceae

    Ebenaceae

    Lauraceae

    Anacardiaceae

    Euphorbiaceae

    Figure 2: Family species richness in Non-Relic transects

    Non-relic transects had family Euphorbiaceae with highest of 8 species followed by Anacardiaceae

    (7) and Lauraceae and Ebenaceae with 6 species each. Families such as Dipterocarpaceae which are

    sure indicators of primary forests were not present in Non-Kan transects due to the secondary nature

    of the forests. Other important primary forest representing families such as Myristicaceae, and

    Lauraceae showed very less species and individual diversity. Euphorbiaceae family with more of

    deciduous undergrowth species were more represented in Non-Kan transects.

    Species diversity

    Only 3 localities Karini, Nilvase and Yadanal from relic transect had significantly more species

    compared to other surrounding forest (figure 3). Others did not show much significance as deciduous

    species contributed for the somewhat higher species diversity in Non-Kan forests.

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 6

    0

    5

    10

    15

    20

    25

    30

    35

    40

    45

    Sp

    ecie

    s n

    o.

    1 2 3 4 5 6 7 8 9 10

    Transects

    Species diversityTot.spp (Relic)

    Tot.spp (Non-Relic)

    Figure 3: Species diversity in different Relic and Non relic transects

    Forest canopy height

    Canopy height was more in the relic forests compared to that of their surrounding forests. More

    prominent were Diptero dominated forests such as Hadgeri (21.90) and Ambephal (19.62) etc., due to

    large emergents like Dipterocarpus indicus and Syzygium gardnerii (figure 4). In Non-relic forests

    such as Talekere the average height was as low as 10.6 indicating the secondary nature of the forest.

    Canopy height

    0

    5

    10

    15

    20

    25

    1 2 3 4 5 6 7 8 9 10

    Transects

    He

    igh

    t

    Aver.height(m) (Relic)

    Aver.height(m) (Non-Relic)

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 7

    Figure 4: Canopy height in different Relic and Non-relic transects

    Tree species dominance based on Important value index (IVI)

    As seen from the IVI, Dipterocarpus indicus an endangered, emergent trees growing to height of 40

    m or more dominated many transects such as Karikan (117.61), Kathlekan (40.82), Ambepal (21.70),

    and Attigodu (18.06). Other notable relic endemics dominating the Kan or Relic transects include

    Poeciloneuron indicum in Karni (71.96) and Yadanal (27.47), Vateria indica in Nilvase (68.26),

    Syzygium travancoricum (33.51) in Kathlekan, and Myristica fatua in Kathlekan-swp (15.18).

    Other important trees with high IVI were Canarium strictum, Aglaia anamalayana, Hopea ponga,

    Garcinia talbotii, Syzygium gardeneri, Knema attenuata, Pallaquium ellipticum, Myristica

    dactyloides etc.

    Non-relic transects had Olea dioca with higher IVI occurring in 6 out of 10 transects indicating the

    secondary nature of the forests. Other trees with higher IVI include Knema attenuate, Holigarna

    arnottiana, Hopea ponga, and Symplocos racemosa.

    Basal area

    Relic-transects had the highest basal area with 85.41 recorded for Karikan with huge Diptero trees,

    followed by Vateria indica for Niluvase (47.47) (figure 5). Non-relic transects like Atvadi had higher

    basal areas contributed by species such as Diospyros crumenata lacking rarer endemics and

    endangered species which highly contributed to the relic transects.

    Per hectare basal area

    10.12

    23.52

    25.69

    29.05

    29.87

    31.39

    31.48

    46.03

    47.47

    76.13

    27.70

    35.87

    38.42

    41.24

    41.29

    48.80

    48.87

    53.61

    53.69

    85.41

    1

    2

    3

    4

    5

    6

    7

    8

    9

    10

    Tra

    ns

    ec

    ts

    Per.hec basa.area(Non-Relic)

    Per.hec basa.area(Relic)

    Figure 5: Per hectare basal area in different transects

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    22nd-24th December 2010 Page 8

    Evergreenness percentage

    Evergreen percentage was highest for relic localities with 90 and above while the non relic forests had

    4 transects below 90 having mixture of other deciduous species such as Terminalia sps,

    Lagerstroemia microcarpa, Glochidion sps, etc., which shows the past opening up of forest canopy

    (figure 6).

    Evergreenness

    10

    20

    30

    40

    50

    60

    70

    80

    90

    100

    1 2 3 4 5 6 7 8 9 10

    Transects

    Everg

    ren

    ness p

    erc

    en

    tag

    e

    %Evg (Relic)

    %Evg (Non Relic)

    Figure 6: Evergreeness percentage in Relic and Non-Relic transects

    Shannon Diversity

    Highest diversity was found in relic forests with Yadanal having 3.15 shannon value. Non-relic

    forests also had higher Shannon diversity which were also contributed by other deciduous species.

    Only in Talekere the Shannon value was low with 1.5 due to Hopea ponga dominance (figure 7).

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 9

    Figure 7: Shannon diversity in Relic and Non-relic transects

    Percentage Western Ghats

    Endemic percentage was highest for all the relic transects with highest being for Karikan sacred grove

    (75.53) (figure 8). Though many of the Non-Relic transects such as Talekere showed higher

    endemism than other relic-transects, this higher endemism was mostly contributed by widely

    distributed common endemics such as Hopea ponga, Knema attenuate found throughout the Western

    Ghats. On the other hand the relic transects had endemic, rare or endangered species such as

    Syzygium travancoricum, Vateria indica, Dipterocarpus indica, Pallaquium ellipticum, etc.,

    contributing more to the endemic percentage (table 3).

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 10

    0

    10

    20

    30

    40

    50

    60

    70

    80P

    erc

    en

    tag

    e e

    nd

    em

    ism

    1 2 3 4 5 6 7 8 9 10

    Transects

    Percentage endemism%W Ghats (Relic)

    %W Ghats (Non-Relic)

    Figure 8: Percentage endemism in Relic and Non-relic transects

    Locality dipind poeind palell myrfat gymcan semkat syztra vatind madbur Status Ambepal-2 + − − − − − − − − Relic attigodu-2 + − − − − − − − − Relic hadgeri-1 + − − − − − − − − Relic hessige-2 − − + − − − − − − Relic Karikan-lower slope + − − − − − − − − Relic karini − + + − − − − − − Relic Kathalekan-G4-obove settlement -slope + − + − − − − − − Relic Kathalekan-G8-swp with S.trav + − + + + + + − + Relic niluvase − − − − − − − + − Relic yadanal − + − − − − − − − Relic

    atvadi − − − − − − − − − Non-Relic

    belamakki − − − − − − − − − Non-Relic

    chikmathur − − − − − − − − − Non-Relic

    gundabala − − − − − − − − − Non-Relic

    halki-2 − − − − − − − − − Non-Relic

    hongodu − − − − − − − − − Non-

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 11

    Relic

    joginmath-1-sidapur − − − − − − − − − Non-Relic

    Kagarasu-mugimane − − − − − − − − − Non-Relic

    salkodu-5 − − − − − − − − − Non-Relic

    Talekere-sidapur − − − − − − − − − Non-Relic

    Table 3: Relic species present in different Kan and Non-Kan transects.

    Discussion

    Non-relic forests were less in all aspects of diversity, evergreenness and endemism compared to Relic

    forests. Relic forests had a total of 47 endemic species compared to only 26 species in Non-relic

    transects. But the real factor of importance for sacred forests emerge in the number of critically

    endangered, and rarer endemics (termed as ‘Relic species’) it harbor, and are the last abodes of

    habitats for these species. Most of the secondary evergreen forests lack these relic species and have

    commoner endemics found throughout the Western Ghats. Uttara Kannada is the northern most

    boundaries for most of these relic species, and they hardly occur further north. Also the rainfall and

    the number of dry period months restrict most of the relic species moving further north. Most of these

    primary relic forests have high water shed values harboring numerous perennial springs and streams,

    compared to dry stream courses in Non-Relic forests. Hence these forests are critical for water shed

    management and loss of these areas would be a death blow to the perenniality of the main river itself.

    Most of these relic forests are now in state of stress due to various anthropogenic factors such as

    logging, land encroachment for Areca and other crop cultivation, fire, small and large developmental

    projects, etc. Many sacred groves are left with only single tree species, and one would hardly be

    surprised such Diptero forest existed before (figure 9).

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 12

    Figure 9: Lone Dipterocarpus indicus tree surrounded by secondary forest.

    All the sacred groves surveyed had high vulnerability for extinction due to encroachment and other

    land use changes (figure10, 11 and 12). Many areas have been burnt and many tree saplings are

    covered with weeds such as Eupatorium, and other invasive weeds and climbers (figure 13, 14).

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 13

    Figure 10: A virtual paradise (sacred grove in back ground) in no forest zone.

    Figure 11: Sacred site in Kan

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 14

    Figure 12: Myristica fatua tree burnt for Areca cultivation.

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 15

    Figure 13: Last gasp of breath for Myristica fatua entangled and covered with climbers and

    weeds.

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 16

    Figure 14: Swamp forests water diverted to Areca gardens leaving swamps high and dry to die

    silently.

    Recommendations

    • To clearly recognize and demarcate the importance of relic evergreen forests from Non-relic

    evergreen forests.

    • Maximum priority to be given to these relic forests as these harbor endangered and rare

    endemics which once lost are lost for ever.

    • To prohibit any kind of human disturbance including litter collection, pole and fuel wood

    collection inside the groves.

    • To declare Kans such as Karikan, Kathlekan etc., as heritage sites for their complete water

    shed protection and restoration.

    • To encourage and appeal resident peoples inside the relic forests for relocating outside these

    forests by providing suitable compensations.

  • Lake 2010: Wetlands, Biodiversity and Climate Change

    22nd-24th December 2010 Page 17

    • Even small fragments of one or two relic trees present should be declared for protection as

    they may be the last remaining populations of these areas.

    Acknowledgement

    We would like to thank Karnataka forest department and staff, Uttara Kannada and Shimoga division,

    for all their assistance in carrying out the project. Thanks to, Dr. Divakar K Mesta, Mr. Sameer Ali,

    Dr. Rajashree Ray, Mr. Vishnu D Mukri and Mr. Srikanth Naik for making this field work a

    successful and memorable event. Finally we thank all those forest dwellers, and other peoples directly

    or indirectly assisted in carrying out this project.

    References

    1. Anderson M. Danica., Jan Salick, Robert K. Moseley and Ou Xiaokun. 2005. Conserving the

    sacred medicine mountains: a vegetation analysis of Tibetan sacred sites in Northwest

    Yunnan. Biodiversity and conservation. 14:3065-3091.

    2. Chandran M.D.S, D. K. Mesta, G. R. Rao, Sameer Ali, K.V. Gururaja and T.V.

    Ramachandra. 2008. Discovery of Two Critically Endangered Tree Species and Issues

    Related to Relic Forests of the Western Ghats.

    3. Gadgil, M., & Vartak, V. D.1981. Studies on sacred groves along the Western Ghats from

    Maharastra and Goa: Role of beliefs and folklore. In S. K. Jain (Ed.) Glimpses of Indian

    ethnobotany (pp.271-278). New Delhi: Oxford and IBH.

    4. Chandran, M.D.S., G.R.Rao, K.V.Gururaja, & T.V.Ramachandra. 2010. Ecology of the

    Swampy Relic Forests of Kathlekan from Central Western Ghats, India. Bioremediation,

    Biodiversity and Bioavailability. Global Science Books.

    5. Hughes, J.D., & Chandran, M.D.S. 1998. Sacred groves around the Earth: An overview. In

    P.S.Ramakrishnan, K.G.Saxena & U.M. Chandrashekara (Eds.) 1998. Conserving the

    Sacred: For Biodiversity management (pp.101-121). New Hampshire: Science Publishers.

    6. Krishnakumar, G. & H. S. Shenoy. 2006. SYZYGIUM TRAVANCORICUM GAMBLE

    (MYRTACEAE) – A NEW RECORD TO KARNATAKA. J. Econ. Taxon. Bot. Vol. 30 No.

    4: 900-902.