SIGNIFICANT RESULTS
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IUCN Red listed plants: The forest studies revealed the presence of six threatened tree species in the transect areas. Kathalekan Myristica swamps and other swamps in Siddapur and Honavar are extremely threatened habitats with threatened species like Myristica magnifica, Gymnacranthera canarica, Syzygium travancoricum and the new tree species Semecarpus kathalekanensis exclusive to the swamps. Dipterocarpus indicus is present in the relic kan forests of Siddapur, Honavar and very rarely in Ankola. (Table-10)
Table 10. The IUCN Red listed tree species found in various transects
Red listed species |
Family |
Category |
Locations |
Taluk |
Remarks |
Gymnacranthera canarica |
Myristicaceae |
Vulnerable |
Alsolli 1, Alsolli 2
Halsolli
Kathalekan G1, G2 Kathalekan swamp T1, T2, T3, T4, T5, T6 |
Ankola
Honavar
Siddapur
Siddapur |
Confined to Myristica swamps only |
Myristica fatua |
Myristicaceae |
Endangered |
Halsolli
Kathalekan swamps T1,
T2, T5, T9 |
Honavar
Siddapur |
Confined to Myristica swamps only. In relics of primary forests |
Dipterocarpus indicus |
Dipterocarpaceae |
Endangered |
Alsolli 1, Alsolli 2
Ambepal 1, Ambepal 2
Hadageri 1, Hadageri 2
Karikan lower slope
Karikan s.evergreen
Karikan templeside
Kathalekan non-swamp grids G1, G2, G3, G4, G5, G6, G7, G8
Kathalekan swamp grids T1, T2, T3, T4, T5, T6, T7, T8, T9 |
Ankola
Honavar
Honavar
Siddapur |
New reports for Ankola
in relics of primary forests. Northward range extention in Western Ghats |
Hopea Ponga |
Dipterocarpaceae |
Endangered |
Widespread in evergreen forests Honavar, Kumta, Siddapur, Sirsi and Ankola and sparingly in Karwar and Yellapur |
Honavar, Kumta, Siddapur, Sirsi, Ankola, Yellapur
Karwar |
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Vateria indica |
Dipterocarpaceae |
Endangered |
Kathalekan 3 |
Siddapur |
Planted widespread in the district; natural in Mattigar kan, Siddapur |
Syzygium travancoricum |
Myrtaceae |
Critically Endangered |
Kathalekan G8,
Kathalekan swamp T3, T6, T8, T5 |
Siddapur |
Also found very sparingly in Ankola Ghats. Range extention in Uttara Kannada reported for first time |
Semecarpus kathalekanensis |
Anacardiaceae |
New tree species |
Kathalekan swamps T1, T2 |
Siddapur |
New tree species reported |
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Endemism: Details of tree endemism were given in Tables 5 & Figure 13. Endemics are exclusive trees to the Western Ghats. Concentration of endemic trees, expressed as percentage of endemism in the sample stands, is more in the southern evergreen forests of Siddapur and Honavar, followed by Kumta and Sirsi. Endemism tends to decline in the northern forests, as most of them are secondary in nature. The Myristica swamps, themselves highly threatened areas, are remarkable for the congregation of Western Ghat endemic trees: Eg. Sample areas from Kathalekan swamps T1 (76.92%), T2 (80.17), T3 (81.75%), T4 (71.7%), T6 (71.43%), T8 (70.4%) and T9 (72.65%). Non-swamp samples from Kathalekan are also rich in tree endemism: eg. T8 (77.96%). Some other high endemic areas are in Tulsani-2 of Honavar (83.2%), Hudil in Bhatkal (80.65), Karikan temple side sample in Honavar (75%), Halsolli in Honavar (79.07%) and from Devimane Ghat in Kumta (74.62%). The northern forests show drastic decline in endemism (Figure 18 for distribution of tree endemism).
Figure 18. Tree endemism levels in different transects of Uttara Kannada
High endemism concentration areas in the Siddapur and Honavar ghats covering the drainage areas of Sharavathi and Aghanashini rivers constituting the backbone of the Aghanashini Conservation Reserve, the main habitat for the Endangered primate Lion
- tailed macaque and for the presence of maximum Myristica swamps in the district (Figure 18). In a recent study 35 amphibian species were reported from Kathalekan, most of them in and around the Myristica swamps. Of these 74% are endmics to the Western Ghats. Philautus ponmudi is Critically Endagered and its northernmost distribution range in Western Ghats ends in Kathalekan. Five of these species are Endangered and yet another 5 are Vulnerable. Several of them being data deficient also might figure in the threat categories of the Red List (Chandran et al., 2010).
- Tree height criteria: In Uttara Kannada forests make a mosaic of secondary ones, due to anthropogenic effects through centuries, in different stages of succession, here and their enmeshing relics of primary forests like the kans. Several tall growing emergent, evergreen, endemic and non-endemic trees like Artocarpus hirsuta, Dipterocarpus indicus, Syzygium travancroicum, S. gardneri, Dysoxylum malabaricum, Calophyllum tomentosum, Ficus nervosa, Lophopetalum wightianum etc.are instrumental in maintaining tiered structure of the forests and in providing habitats for several birds (eg. Imperial pigeon, hornbills), bats and Lion-tailed macaque. Vertical compression of forests can adversely affect primary forest arboreal fauna.
- Conservation value and basal area: Old growth and primary forests tend to accumulate more biomass, as reflected in the girth of tree trunks. Naturally, long periods of undisturbed growth will increase tree dimensions as could be seen from the basal areas/ha. Several endemic tree species are associated with high basal area forests and increase their conservation importance. High basal area is index of high biomass and high levels of carbon sequestration. Human impacts in the form of logging can reduce stand basal areas. Selective cutting may not eliminate tree species as such in a mixed stand. Therefore the consefvation value of the stand may not suffer seriously through some degree of forest exploitation. But forest exploitation through tree cutting and mutilation can severely alter the faunal composition by upsetting their habitat qualities. Forest stands of exceptional conservation values should have at least over 40 m²/ha of tree basal area in Uttara Kannada conditions.
- Significance of diversity: Biodiveristy, in terms of genetic, species and ecosystem diversity, is paramount in considerations of conservation. Biodiversity on the earth is getting seriously impacted due to various human activities, directly (through exploitation and alterations in habitats for human wants) and indirectly (through pollution of land and water and air and climatic changes). Protecting of biological diversity has economic and ethical grounds. The species have their own intrinsic values unrelated to human needs. In the complexity of biological communities loss of one species may have far reaching consequences affecting even the humans. As far as forest tree diversity in Uttara Kannada forests (expressed in Shannon diversity index of sample areas) is considered it is found that conservation values of tree community expressed as a composite value are not necessarily dependent on high diversity index, though there is tendency towards increase in conservation value with rising diversity index. Stand should not be however too poor (diversity value of 1-2 in our study areas). Several stands of climax vegetation are too specialised to their habitats (eg. Myristica swamps), so that they are not that rich in tree species but are seats of high Western Ghats endemism. The Myristica swamps and their immediate surroundings abound in endemic individuals of similar nature so much so the stand diversity as expressed in Shannon index ranges between 2-3 only, unlike many secondary disturbed forests which have diversities of 3-4.
- Prioritsation of forest areas for conservation: On the basis of the composite conservation index prepared for assessing the plant diversity (mainly trees) conservation value of stands in forests, based on 116 transects, each covering 2000 m² of forest, a map has been prepared and presented here (Figure 19). High and very high conservation ranking areas (conservation values of ≥ 80) are along the Western Ghat regions in the south of the district, mainly in the taluks of Honavar, southern Siddapur (Kathalekan-Malemane area), a zone of high percentage evergreen forests with high degree of forest endemism. If faunal endemism is added to these areas the conservation values will continue to increase compared to the northern taluks. Conservation values of moderate importance are found in sites throughout the district, scantily so in Mundgod, Joida and Haliyal taluks- despite the fact that these are of high conservation value for non-endemic mammals and flagship species like elephant and tiger. As bulk of the Dandeli-Anshi Tiger Reserve is in Joida, Karwar and Haliyal taluks (as we had no permission to work in such areas, our reliance is more on few samples studied earlier to the new regulations imposed on scientific studies in the Tiger Reserves within the State). As savannah, deciduous forests and more of open grassy areas exist especially in Joida taluk, as telltale marks of its shifting cultivation history, the grazing ecosystem fares better here ideally promoting tiger and panther and other carnivores through promotion of herbivorus prey animals. Not belittling in any way the importance of major mammal conservation in National Parks and Sanctuaries of Western Ghats, as far as Uttara Kannada is concerned scanty efforts were ever made to conserve pockets of high endemism, which is the major consideration for conferring Biodiversity Hot Spot status for the Ghats as a whole. Our studies on forest vegetation clearly reveal that high evergreen forest areas, with negligible timber values, unlike the deciduous forest zone of the district of north-eastern taluks, have greater endemic biodiverisity as reflected in the forest stands.
Moreover, in studies related to fresh water fishes of Sharavathi River tributaries in Shimoga taluk it was found earlier that the landscape elements in the catchment of the tributary plays a decisive role in especially fish endemism. A tributary, for instance like Yennehole, had 18 species of fishes of which 8 were Western Ghat endemics. The catchment area forests in Yennehole basin had 86 to 100% evergreen trees where endemism varied between 46-58%. Yet another tributary Nagodi with 19 fish species had also 8 endemic fishes, including a new species Schistura nagodiensis, and 68-99% evergreen forests with 36-71% tree endemism in the drainage basin. In contrast Nandihole tributary flowing through a degraded landscape of highly human affected forests, agricultural areas and monoculture tree plantations, with merely 0-16% evergreenness and low endemism of 0-11% in the catchment forests. Although there were 14 fish species in the river only 2 were endemics. The message is that the evergreenness of forests, which goes in harmony with endemism, plays a very crucial role for the entire forest and linked ecosystems in the Western Ghats, as landscape elements play decisive role in distribution of aquatic organisms like fishes making untrammelled nature a holistic system (Sreekantha et al., 2007). High tree endemism areas of Kathalekan, especially the Myristica swamps and adjoining damp areas, had at least 35 species of amphibians. Already we have referred to the amphibian richness of the swampy Kathalekan evergreen forests with high percentage of tree endemism. Conservation values assigned for forest areas for prioritisation of conservation, using the composite index is given in Figure 19.
Nelson et al (1990), Peterson et al (2000) and Myers et al (2000) strongly favour identification and prioritisation of `hotspots', or areas featuring exceptional concentrations of endemic species and experiencing exceptional loss of habitat. Their focus is more on endemic species, rather than populations or other taxa, as the most prominent and readily recognizable form of biodiversity.
Using a grid system (preferably 1x1 km) of forest surveying we need to have a proper stock of the distribution of endemic tree species, and demarcate areas of high tree endemism for prioritization of conservation as such areas are also good for endemic faunal elements and for their hydrological importance. Centres of high floristic endemism (of especially trees) are also the centres of endemic fishes in the streams draining them, in addition to amphibians and birds.
Figure 19. Tree diversity conservation values of forest stands in Uttara Kannada (for non-economic parameters)
The role of man-made plantations needs a re-evaluation, in the light of high soil erosion, weed infestation, poor hydrology and poor associated faunal diversity as compared to natural forests (Murthy et al., 2002; 2005). The teak plantation areas in general, despite the high value of teak timber, were found to have lower biomass and needs enrichment planting by NTFP species, nectar species for honey bee promotion, Soil erosion from forests and forest plantations is a matter of grave concern. As rains are often very high (upwards of 3000 mm/per annum) in most places, and so much of rains fall within a short period of mostly four months a dense forest cover is required to check soil erosion and increase infiltration into the ground water. Here we recommend eventual conversion of deciduous forests and their degradation stages (except grasslands or grassy blanks, critical resources for grazing ecosystems) in heavy rainfall zone into evergreen forests. Poor grade tree plantations with eroded soils need to be restored with natural forest species through planting of saplings and dibbling of seeds.
Forest restoration in the catchment areas of rivers will improve perennial nature of streams ensuring perpetual inflow of clear water into the storage dams of hydroelectric projects in Sharavathi and Kali rivers than bringing into them an onrush of water turbid with soils down the poorly vegetated terrain. The active monsoon period being of four months it is necessary to increase residency of water within the watershed soils than releasing it en mass into the reservoirs or other downstream areas as surface water, which eventually get lost through faster evaporation in the prevailing climatic conditions.
The species chosen for forest enrichment/afforestation should have strong bearing on a. increase in endemism; b. more of ecologically site specific NTFP species; c. benefit to birds and bats and other frugivorous animals and d. favour populations of wild bees and create employment opportunities through bee-keeping and enhance pollination services of both cultivated crops and forest plants.
A system for assigning conservation values to the forest patches based on characteristics of tree communities has been adopted here. Assignment of conservation priorities is based mainly on five variables of forests namely: a). % evergreenness, b). % endemism, c). basal area, d). tree height and e). Shannon diversity index. Principal component analysis based on the first four variables revealed that evergreenness of the forests is strongly linked to the presence of endemic trees. Higher the evergreen components more endemics congregate in such areas. Basal area and tree heights are linked to other two factors – but not so strongly as these two are subjected to rapid fluctuations depending on human impacts. Relative correlation between these five factors was obtained through application of Pearson correlation matrix. A composite conservation index is prepared for the 116 forest samples using scores allotted to the factors %endemism, mean canopy height, basal area and diversity index. Additionally the presence of IUCN Red Listed trees, if any, were given high conservation score- the actual score depending on the category of threat.
Highest conservation values are more for forests towards the south from Sharavathi Valley (Kathalekan-Malemane-Gersopppa stretch to the Aghanashini valley in Siddapur and to a small extent in Sirsi). Incidentally this stretch of forests, having the northernmost populations in the Western Ghats of the Endangered primate Lion-tailed macaque, of Myristica swamps and Dipterocarpus trees, has been already declared by the Government of Karnataka as Aghanashini LTM Conservation Reserve.
The study reveals that there is only a thin line difference between rain forests and deserts. Whereas the heavy rainfall of coast and malnadu taluks can potentially promote loftiest evergreen forests of Western Ghats many locations are characterized by poorer vegetation- poorer in biomass and in conservation ranking. The poorest savanna site exists on a hill top ironically in the Kathalekan forests of highest conservation value, dotted with Myristica swamps, by presence of lofty Dipterocarpus threatened and endemic plant and animal species (especially amphibians and LTM). Whereas the swamp forest samples of Kathalekan have average carbon sequestration of 225.506 t/ha the savanna patch has merely 5.06 t/ha. The land was savannized at least over 100 years ago by the shifting cultivators. Though today uninhabited the forest recovery has not taken place. Similar paradoxes exist between adjoining forest patches everywhere in the district.
Whereas in the earlier efforts towards conservation it was often the flagship species like elephant, tiger etc. and their habitats that captured major attention in the conservation priorities of the Government. Today, the Western Ghats, along with Sri Lanka constitute a hotspot of high endemism and significant threat of imminent extinctions. Therefore it has become necessary to evaluate and rank areas of high endemism, which we have attempted in this study through the application an objective method. Suggestions based on our sustained ecological research in Uttara Kannada district are:
- In the specter of climatic change that the planet is facing with its widespread implications especially on farming and biodiversity, the need has arisen to increase carbon sequestration in the forest areas. There are considerable areas of degraded forests in Uttara Kannada, the biomass of which has to be increased substantially through protection, enrichment and co-management.
- Inviolate forests should be identified range-wise for increased conservation efforts.
- Myristica swamps are among the oldest and original forest types of the Western Ghats. They have some of the highest degrees of floral and faunal endemism. Efforts should be made to make all out search for such swamps, record their locations and areas and conserve them along with their catchment area forests
- The kan forests and ‘devarabanas’ were unique cultural identities of bygone days. They still have portions harbouring deities and are seats of high endemism. As most of them got merged with state reserved forests they lost their pre-colonial identities as sacred groves from safety forests (except the smaller banas close to or in the middle of villages) Efforts should be made to trace them out and map and protect them.
- Conservation of Western Ghat endemism is important. High percentage of forest tree endemism even influences endemism among fishes in the streams that drain such forests.
- Biomass upgradation is an urgent necessity especially in the deciduous forest areas everywhere, especially in the maidan taluks of the district.
- Biomass and diversity are lower in the coastal minor forest tracts. Through consistent efforts involving local VFCs multiple species forests should be raised in such areas.
- Coastal lateritic hills were paid least attention so far; except for raising Acacia plantations no major activities were undertaken in them. Laterite plateaus also have great richness of monsoon herbs which flower gregariously and offer nectar for the survival of honey bees during the rainy season. Some ideal plateaus need to be conserved for their characteristic endemic flora.
- Regarding scope for forestry based alternative development plan for enhancing the economic productivity of the region we wish to state that since bulk of the lands in the district (over 70% area) being under the control of the Forest Department there is very little scope for economic advancement of bulk of the local population beyond subsistence level. There is also not much scope for major developmental interventions due to the fragility of the terrain and the ecosystems. As economic growth gets stunted people, especially younger generation tend to migrate into the cities for better prospects. Such mass migrations from rural areas will strain the cities as well beyond their carrying capacities too- as it is happening in Bangalore. To reverse the trend as far as Uttara Kannada is concerned the following recommendations are made for creation of more of forestry based livelihoods without any major interventions into the ecosystems as such:
- NTFP species should be widely raised
- Bee keeping to be promoted as an important enterprise to benefit the people and forests (through pollination). Village peripheral forests and roadsides should be planted with numerous types of nectar plants used for foraging by honey bees (separate submitted on bee keeping0.
- There is laxity among the arecanut garden owners as regards management of soppinbetta forests for fear of not getting the fruits of such improvement as the bettas are under Government ownership. It is recommended the betta owners be allowed certain tree rights if they adhere to certain norms like maintenance of the bettas to certain biomass levels, say like 30-35 sq.m of basal area/ha for trees.
- The farmers require a helping hand from the Government in growing and marketing of medicinal plants and their primary products. Medicinal plants grown in VFC forests in home gardens or in fields, which also grow wild in the forest areas, should be procured by the Forest Department. This is to stop smuggling of medicinal plants from the forests, unauthorized exploitation by outside agencies and for betterment of local livelihoods.
- Preparation of bio-pesticides, harmless to humans and domestic animals, may be promoted as a cottage industry using local plant resources, especially from village peripheral forests/VFC managed areas.
- Vegetable dyes/or textiles coloured using such dyes, or for use as food colours are in increasing demand. Numerous plants in forests, mangroves and beaches are potential sources of such dyes. Village peripheral forests may be enriched using such plants to generate rural employment. Technology transfer is necessary.
- Enormous scope for exploration of production and trade of plant based cosmetics and nutraceuticals (eg. from Garcinias and Phyllanthus emblica -amla) should be explored.
- VFC managed sandalwood farms are recommended for the taluks of Haliyal, and Mundgod and for the eastern zone of Yellapur, Sirsi and Siddapur.
- Being well forested district of hills and valleys, waterfalls, sea beaches and mangroves and for its cultural diversity Uttara Kannada has good scope for generating eco-friendly livelihoods through tourism promotion at grassroots level. This facet of development with the vision of upgrading livelihoods of grass root level people while also enriching forests, mangroves, sea beaches and coastal laterite plateaus has been successfully worked out by the Honavar Forest Division, at Apsarakonda, Om Beach (Gokarna), Kasarkod, Bellangi etc. The State Government should liberalise the licensing policy on home stays and community managed cottages (through VFCs) to benefit growth of decentralized ecotourism in the district, to benefit both village communities and local ecology.
- Decentralised systems of forest nurseries for generating women’s employment and providing scope for application of indigenous farming techniques for forestry purposes.
- Village level biodiversity hotspots should be identified and protected through the involvement VFCs/local Biodiversity Management Committees. Eventually these, through succession and vegetational enrichment will turn out to be local hotspots of biodiversity.
- Realizing the fact that depletion of forests of food resources and human induced vegetational changes in forests have adverse consequences on wildlife while increasing crop raids by animals enrichment of secondary forests and poor grade tree plantations with food resources for forest herbivores is highly desirable.
- NTFP collection, that yields only minor revenue to the state, is being carried out in many forests with gay abandon causing destruction of the resource itself. We recommend that the VFCs and other forest dwellers in respective villages be organized and trained in scientific harvesting of NTFP which also serves as medicinal plants
- Rampant collection of poles, cane, fuel wood etc., has been taking a heavy toll on forest resources particularly in the village vicinities. Most of the easily accessible areas with many medicinal plants are more prone to exploitation and get converted into scrub and thickets. Even the semi-evergreen and evergreen forests higher up in more inaccessible areas are also being exploited for fuel wood, timber etc., due to which many of these forests have thorny thickets as under-growths. We recommend conduct of sustained programmes on biodiversity awareness. Also bamboo considered as ‘poor man’s timber’ the villagers may be allowed to harvest it from designated areas for their own bonafide use, so that they will desist from pole cutting and stake removal from the forests which destroys lakhs of tree saplings and pole sized juveniles.
Citation : Ramachandra T.V., Subash Chandran M.D., Rao G R, Vishnu D. Mukri and Joshi N.V., 2015. Floristic diversity in Uttara Kannada district, Karnataka, Chapter 1, In Biodiversity in India-Vol. 8, Pullaiah and Sandhya Rani (Eds), Regency publications, New Delhi, Pp 1-87
Corresponding author:
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Dr. T.V. Ramachandra
Energy & Wetlands Research Group, CES TE 15
Centre for Ecological Sciences
New Bioscience Building, Third Floor, E –Wing
[Near D-Gate], Indian Institute of Science,
Bangalore – 560 012, INDIA.
Tel : +91-80-2293 3099/2293 3503 - extn 107
Fax : 91-80-23601428 / 23600085 / 23600683 [CES-TVR]
E-mail : cestvr@ces.iisc.ernet.in, energy@ces.iisc.ernet.in,
Web : http://wgbis.ces.iisc.ernet.in/energy |
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