STUDY OF ECOLOGICAL AND ENVIRONMENTAL STATUS OF UPPER CATCHMENT AREA OF PAMBA RIVER BASIN USING SATELLITE DATA

Funding Agency: NNRMS Standing Committee on Bio Resources and Environment, Ministry of Environment and Forests, Government of India.

Natural resources play a significant role in determining the physical, economic, social and cultural welfare of a country. While natural resource availability is limited, the nature and type of demand is varied aggravating environmental conflicts. Thus the natural resources of the earth, including the air, water, land, flora and fauna and especially natural environment must be protected for the benefit of the present and future generations through careful planning and management. Pamba River is one of the major rivers draining Pandalam Hills, north of Agasthya Malai range in the Southern Western Ghats. The famous forest shrine of Swamy Ayyappa (Sabarimala Pilgrim Centre) is situated amidst the northwestern foothills of Pamba plateau. Over the years it has become the most popular pilgrim centres in South India and millions of pilgrim visit the shrine especially during the winter season. The gathering of very large crowd over a short period of time in an ecologically sensitive area has resulted in various environmental problems. This project had envisaged to study the Ecological and Environmental Status of Upper Catchment Area of Pamba River Basin using Satellite Data giving focused attention to the environmental changes in Sabarimala and surroundings and to formulate catchment area treatment and conservation plan based on the study. The project also tried to identify ecologically and environmentally fragile areas, to study the present land use pattern and the land use changes over the years in comparison with different land form units, to assess the land capability and land use systems of different critical areas of the basin; to study the environmental pollution problems in the area especially water pollution in the upstream area of Pamba river and degradation in biomass due to congregation of pilgrims.

The Landuse maps of 1977, 1989, 1990, 1993 and 1997 prepared from sources like toposheets, airphotos and satellite data show considerable changes in the Landuse especially around Sabarimala Temple and along the approach roads and footpaths. Considerable degradation is also observed around Pamba and Kakki reservoirs. A comparative analysis of the land uses of 1997 with the status in 1977, clearly defined the changes taken place during the last twenty years. The changes were mainly in the form of conversion and degradation of forests into forest plantations, scrub areas and other non-forest activities. The entire study area was divided into three major zones mainly based on the level of human intervention. In the first zone, major changes are from forest to forest plantations whereas in Zone II the area shows a considerable amount of degradation. The third zone is more or less unaffected as compared to other zones. Major observations of the Land use comparison were that the actual forest area has been reduced considerably during the last twenty years; the percentage of reduction comes to about 10.5 %. The scrubland, both open and dense, had also increased considerably which is an indicator of forest degradation. Grassland area was also showing an increasing trend upto 1993 but it is considerably reduced during 1997. One of the major reasons for the increase in area of grassland may be due to the degradation of forest area cleared for power line inside the forest. The plantation area has also increased considerably during these period and rubber plantation shows about 51% of increase.

The Pamba River from the immediate upstream of Sabarimala Sannidhanam to lower reaches is highly polluted especially during the festival seasons due to the huge quantity of waste generated by millions of pilgrims visiting the area. The pollution is mainly due to human excreta along with the biodegradable waste like used leaves, vegetable wastes, food wastes etc. The sanitation facilities are totally inadequate considering the overall demand and almost all the solid waste generated on the way and around Sannidhanam ultimately reaches the Pamba water. The water samples were analysed for major physico-chemical and bacteriological parameters like pH, Temperature, Hardness, Dissolved Oxygen, BOD, COD and Ammonia using the standard methods for physico-chemical analysis and faecal coliform test for bacteriological analysis. It was found that the samples collected were comparatively good in terms of physico-chemical condition except BOD and COD but highly contaminated with bacteria.

The open and dense scrubs in the proximity of Sabarimala were suggested for appropriate conservation measures like afforestation with species like reeds, bamboo etc. The degraded areas along the three major routes to Sabarimala are suggested to be protected from further degeneration after providing a buffer area around the existing foot road. The buffer area can be afforested with species which can be utilised by the pilgrims for their use and thus to minimise the dependence of natural forest for meeting their various needs during pilgrimage. In the plateau region, near to the reservoirs there are problems of high erosion, slope failure and slumping along reservoirs. Soil management practices and erosion control measures like afforestation with reeds, bamboo etc., can be considered in this area.

The analysis of the different maps prepared during the study revealed that, a major part of the degradation of forest have taken place in and around Sabarimala Sannidhanam area, mainly due to the pilgrimage over the years. In the project, special emphasis was given to study the ecological status of Sabarimala and its immediate environs as a focussed area. A buffer area around Sabarimala coming under 3.2 km radius from Sannidhanam was identified as the most affected area due to the pilgrimage. Considering the fragility of the area, it is suggested that devotees should not be allowed to spend more than 2-3 hours at the Sannidhanam area and arrangements should be made to take rest and other activities in the peripheral area of Sabarimala. No permanent structures and development activities should be allowed further at the Sannidhanam area or its immediate surrounding and all further developments in the form of buildings, roads etc should be located at the already degraded areas beyond Pamba (Triveni). The Satellite Townships can be located in degraded forest area/plantation areas and without affecting the existing evergreen forests. Base camps for taking rest, bath and other activities can be established here for pilgrims coming from different places and the Devaswom Board should arrange transportation facilities. From Pamba to Sannidhanam, the devotees have to adopt trekking for about 4.5 km as usual. Tram services may be arranged from base camps to Pamba. Similar facilities can be arranged for pilgrims coming through the Vandiperiyar route. Here base camps may be arranged in the degraded grassland area from where there is foot road to Sannidhanam or on the way from Vandiperiyar to Vallakkadavu. Base camps can be arranged at Azhutha area on the way from Erumely route. Shops and all other facilities may be restricted to the base camp area except medical facilities, which has to be arranged in several places on the route. Human excreta and other degradable solid wastes were suggested to be utilised for generation of biogas. The non-degradable wastes like plastic, bottles, metal cans etc., can be recycled. The existing sanitary facilities both at Pamba and Sannidhanam area have to be enhanced both in quality and quantity in order to meet the emergency requirement. Programme for providing safe and quality drinking water should be given important thrust.