Terrestrial Biodiversity
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LAKE - 20I2: National Conference on Conservation and Management of Wetland Ecosystems LAKE-2012 Technical Session II Terrestrial Biodiversity 1 School of Environmental Sciences, M. G. University LAKE - 20I2: National Conference on Conservation and Management of Wetland Ecosystems LAKE-2012 L - 01 Forest Endemism in Relation to Hydrology of Western Ghats Subash Chandran M.D., Rao G.R., Rajasri Ray and Ramachandra T.V. Energy & Wetlands Research Group, Centre for Ecological Sciences, Indian Institute of Science Bangalore – 560 012, INDIA E-mail: [email protected]; [email protected]; [email protected]; [email protected] http://ces.iisc.ernet.in/energy Parting from Madagascar (88-90 m.y.a) and from Seychelles (65 m.y.a) left the Indian sub-continent lone in the Tethys Sea, like an island, drifting northwards, paving way for biological evolution in isolation and development of higher endemism. Tropical rain forests flourished all over during the slow process of crossing the equator, through several million years. Merger with Eurasia resulted in the rise of Himalayas causing increased aridity and monsoonal climate with rain forests persisting in only small pockets, like the North-East and South Indian Western Ghats. Western Ghats exhibits latitudinal decline in wetness, its south (8-10°N lat) closer to the equator, having higher humidity and 9-10 rainy months due to summer showers and monsoon rains. Progressively northward reduction in rainy months, down to 3-4 in northern Maharashtra (18-20°N), creating differential dryness, decisive in forest related endemism, is reflected in northward decline in tree endemism, viz. 250 tree endemics in 8-10°N lat, 222 in 10-12°N, 139 in 12-14°N, 79 in 14-16°N, 38 in 16-18°N and merely 22 tree endemics in >18°N lat. As progressive desiccation northwards is a critical factor, the endemics tend to persist around hydrologically richer parts of forests. Agricultural beginnings in the Western Ghats three millennia ago, concomitant with use of fire and axe, affected primeval forests, causing decline in endemism and spread of secondary vegetation. However, relic primary vegetation persisted in higher altitudes, in gorges of rivers and in sacred forests preserved as part of local cultures. These relics were also badly affected beginning in European times with commercial forestry, monoculturing of trees and higher altitude plantations of tea and coffee. Studies in the Sharavathi river basin of central Western Ghats reveal that higher evergreenness of forests, with higher tree endemism in the catchments of tributary streams, favour endemic fresh water fishes. Swamp and stream laced Kathalekan sacred forest in Sharavathi basin is a refugium for endemic plant species including threatened ones. The forest-swamp complex of Kathalekan, in just 2.25 sq.km area had 35 amphibian species, almost equal to the amphibians of the entire Maharashtra. Study in the coastal Honavar taluk of Sharavathi basin, on hydrological significance of endemism rich Karikan sacred forest on a hill top, in comparison with a nearby hill clad in secondary forests reveals 3 School of Environmental Sciences, M. G. University National Conference on Conservation and Management of Wetland Ecosystems LAKE-2012 year-round recharge of ground water from the Endangered Dipterocarpus indicus dominated sacred forest, enabling the village community in the valley down to concentrate on highly remunerative garden crops. In contrast is the water scarcity hit, poorer farming community in the village below the secondary forest, where rain-fed rice and garden crops together yield only 50% income of the former. The studies highlight the need for urgent conservation of hydrologically rich forests which are also centres of endemism. Keywords: Western Ghats, Biodiversity, Endemism, Hydrology, Ecology, Sacred groves, Sharavathi river L - 02 Swarming of the Termite Coptotermes Heimi in Northeastern Puducherry Region K. Harit, S. Gajalakshmi, and S. A. Abbasi* Centre for Pollution Control and Environmental Engineering Pondicherry University, Puducherry 605 014, India * Corresponding author <[email protected]>; Mobile: 94432 – 65262 Even though the main thrust of research on termites across the world remains on their control or ‘eradication’, interest on their lignin-digesting ability is also growing. Termites are among very few species of insects which can ingest lignin and have it decomposed either by the microflora (present in the guts of ‘higher’ termites) or by the protozoa (living symbiotically in the guts of ‘lower’ termites). Exploration of this lignin-digesting ability, hence the biology, of termites is aimed at finding ways by which lignocelluloses biomass can be decomposed into simpler sugars for the eventual liquid biofuel production. Compared to other insects with lignin digesting ability termites are much more widespread and numerous, hence the special attention on them. Coptotermes heimi is a ‘lower’ termite which is very widely distributed in many parts of the world, including most of India. As in the case of most other termite species, C. heimi attains its dispersal by the process of alate emergence, forming of swarms away from the parent colonies, and the mating of dealates. It also has the relatively uncommon (among the termites) ability by which its workers can metamorph into reproductives when isolated from parent colonies but the main process of reproduction and colony initiation occurs via alate swarming. In view of the above we have carried out studies over a four year span on the swarming behavior of C. heimi. Details are presented in this paper, which show in that four years C. heimi swarms occurred 17 times of which 14 occurred in June and the remaining three in the first half of July. All the swarming occurred after sunset and after rain. In 15 of the instances, the alates were in the air for 15 – 20 minutes, whereas in other two cases, the flight was for 35 minutes and 60 minutes. There was sharp year-to-year variation in the number of swarmings – 1, 7, 4, and 5 swarmings occurred in 2009, 2010, 2011 and 2012 respectively. Keywords: termites, Coptotermes, swarming, alates, Puducherry 4 School of Environmental Sciences, M. G. University National Conference on Conservation and Management of Wetland Ecosystems LAKE-2012 L - 03 Status of Forests in Shimoga, Central Western Ghats Sudarshan P. Bhat, Subash Chandran M. D. and Ramachandra T. V. Energy & Wetlands Research Group, Centre for Ecological Sciences, Indian Institute of Science Bangalore – 560 012, INDIA E-mail: [email protected]; [email protected]; [email protected] http://ces.iisc.ernet.in/energy Western Ghats mountain ranges constitute the beautiful array of mountains along the western coast of India. It separates the Deccan Plateau from a narrow coastal strip along the Arabian Sea. This particular mountain range starts from the southern part of the Tapti River near the border area of the states of Gujarat and Maharashtra. Western Ghats mountain ranges cover a length of around 1600 km running through the states of Maharashtra, Goa, Karnataka, Tamil Nadu and Kerala finally terminating at Kanyakumari district, in the southern-most tip of the Indian peninsula. The Western Ghats is rich with different kind of vegetation and topographical features. This bioregion is highly rich with flora and fauna and is considered as one of the 34 biodiversity hot spots of the world. The stretch of Central Western Ghats ranges from 12° to 14°covering areas of Coorg district, Hassan, Chikmagalur, Shimoga upto south of Uttara Kannada. The status of forests in Shimoga was studied by reviewing the working plans, administrative reports, settlement reports and other available research papers. There are five types of forests in Shimoga district: - Southern tropical wet evergreen forests, Southern tropical semi evergreen forests, Southern tropical moist deciduous forests, Southern tropical dry deciduous forests and Southern tropical Scrub forests. The district comprises of three forest divisions- Shimoga, Bhadravathi and Sagar. The forests of the district, which yield rich and valuable products, covered an area of 4, 34,516 hectares nearly 40.27 % of the land in the district. The areas of different types of Forests are as follows: Evergreen forests- 69459 hectares (16%), Semi-evergreen- 88135 hectares (20.28%), Moist deciduous- 130612 hectares (30.06%), Dry deciduous -109539 hectares (25.21%) and Scrub Forests-24111 hectares (5.55%). The Kan forests which are most often climax evergreen forests preserved through generations by village communities of Malnadu regions as sacred forests or sacred groves and were characteristic in Shimoga district. During the field investigations, it was observed these ecological sensitive habitats are being destroyed and encroached at Halmahishi and Kullundi villages. Kans jurisdiction is under revenue department instead of forest department is the prime reason for partial or complete conversion for alternative land use. Large amount of forest were allotted to the Mysore Paper Mills for raising of pulpwood plantations. The chief sources of forest revenue in the district were the hard and soft woods and sandalwood exploited for commercial purposes. Some forest areas were cleared and assigned to the landless and other needy persons to meet the continuous demand and more land for agricultural purposes. The study in the Kurnimakki-Halmahishi kan of about 1000 ha reveals the vegetation of the kan, though heavily fragmented, due to ever increasing human impacts, nevertheless, is a mosaic of 6 School of Environmental Sciences, M. G. University LAKE - 20I2: National Conference on Conservation and Management of Wetland Ecosystems LAKE-2012 various kinds of forests. The most significant is the discovery of swampy areas within this kan which have few individuals of large sized threatened tree species Syzygium travancoricum, classified in the IUCN Red List as “Critically Endangered”. The tree is on the verge of extinction, and for the Shimoga district, the only occurrence of this tree is the Kurnimakki-Halmahishi kan.