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ENVIS Technical Report: 29
October 2008
Ecological Status of Kali River Flood Plain |
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2.0 Introduction
Ecological status of an area is determined by assessing the biodiversity of a region, the environmental conditions prevailing there and their interaction. It represents the overall health and sensitivity of an ecosystem. Ecological status assessment becomes essential for arriving at an appropriate conservation and sustainable management strategies. This assessment is done by evaluating the components along with its functional abilities of an ecosystem. This includes the assessment of species diversity, their abundance, and threats to their habitat by anthropogenic activities (like mining, dam construction, making of road or railway lines, spread of gas pipelines, building of an industry) which may alter the physical, chemical and biological integrity of the system (Ali et al, 2007, Ramachandra et al, 2006). An attempt has been made to assess the ecological status of flood plains of Kali river in the Central Western Ghats, India considering bioindicators, assessment of water quality and land cover.
Birds serve as a good ecological indicator as they inhabit almost every kind of habitat, they are at the top of food chain and thus vulnerable to bioaccumulation of toxic chemicals, they have representatives feeding on full range of animal diets (from insectivores to frugivores). For a healthy number and range of species a diverse ecosystem is needed, a lower number than expected number or range of species in an environment indicates poor ecological diversity. Amphibians are typically living at the interface between terrestrial and aquatic habitats. They are the only vertebrate group with dual life stages (i.e., tadpoles and adults) and considered as biological indicators for their sensitivity and response to very small changes in the surrounding environment. New species are discovered at much higher rate in the past two decades, paradoxically, they are on decline globally. Habitat destruction and overexploitation are the major threat for amphibians, apart from Chytrid fungus and other synergistic effects of human induced changes. Considering these aspects, it was felt that monitoring amphibian diversity and their distribution would provide an insight on the prevailing conditions of an ecosystem and its health, which in turn helps in prioritizing the region for immediate conservation and management action in the Western Ghats, India.
2.1 India - A Mega Diversity Country : Glance of biodiversity
A region with vast reservoir of floral and faunal diversity is often referred as hotspots of biodiversity. The presence of two of the world’s biodiversity hotspots in the vast terrain makes India one of the top 10 mega diversity countries in the world. India’s biodiversity constitute 7% of the world’s flora and 6.5% of the fauna spread in the 10 biogeographic areas namely Trans- Himalaya, Himalaya, Desert, Semi Arid, Gangetic Plains, Western Ghats, Deccan Plateau, Coast and Andaman and Nicobar Islands. (Jafar and Rehman 2008). There are about 614 species of amphibians and reptiles, 1225 species of birds and 350 species of mammals in India. Among which 173 species of mammals, 75 species of birds and 208 species of reptiles are considered threatened. With 1.0287 billion populations (year 2001) the human density of India reached 325 individuals per square kilometer (21.3 % rise from the previous year), the population of India is projected to be between 1.4 to 1.5 billion by the year 2050. With this rapid increase in population the pressure on the natural resources is bound to increase at the same time for the sustenance of life conservation of the natural resources should also be given a priority. The large demand for the land and the socio economic issues is posing challenges in declaring an area as protected. Hence, the focus now is to protect the areas with high biodiversity or which are inhabited by rare or threatened organisms, or have unique habitat or under threat to destruction.
2.2 Western Ghats: Hottest Hotspot of Biodiversity
The Western Ghats, is a chain of mountains, stretching north south along the western peninsular India for about 1,600 km, harbours rich flora and fauna is one among 34 global biodiversity hotspots (Myers, et al., 2000, Sreekantha et al., 2007). Various forest types such as tropical evergreen, semi-evergreen, moist and dry deciduous and high altitude sholas mingle with natural and manmade grasslands, savannas and scrub, in addition to, agriculture, plantation crops, tree monocultures, river valley projects, mining areas and many other land-uses. Over 4,000 species of flowering plants (38% endemics), 330 butterflies (11% endemics), 289 fishes (41% endemics), 135 amphibians (75% endemics), 156 reptiles (62% endemics), 508 birds (4% endemics) and 120 mammals (12% endemics) are among the known biodiversity of the Western Ghats (Daniels, 2003., Babu, et al., 2004., Dahanukar et al., 2004., Gururaja, 2004., Sreekantha, et al., 2007). Table 1 lists the number of organisms found in Western Ghats with their endemism status.
Table 1. List of organisms found in Western Ghats with their endemism percentage.
Group |
Total |
Endemic Species |
% Endemism |
Angiosperm |
4000 |
1500 |
38 |
Butterflies |
330 |
37 |
11 |
Fishes |
289 |
118 |
41 |
Amphibians |
135 |
101 |
75 |
Reptiles |
156 |
97 |
62 |
Birds |
508 |
19 |
4 |
Mammals |
120 |
14 |
12 |
This rich biodiversity coupled with higher endemism could be attributed to the humid tropical climate, topographical and geological characteristics, and geographical isolation (Arabian Sea to the west and the semiarid Deccan Plateau to the east). The Western Ghats forms an important watershed for the entire peninsular India, being the source of 37 west flowing rivers and three major east flowing rivers and their numerous tributaries. The four major rivers (Kali, Bedthi, Aghanashini and Sharavathi) of Uttara Kannada district of Karnataka together account for 92 fish species. However, these ecosystems have been, experiencing tumultuous changes due to unplanned developmental activities, especially during the last century. The drainage basin of River Kali is one such biodiversity rich region in the Western Ghats of Uttar Kannada district, which has been over exploited for the production of energy.
2.3 Uttara Kannada district, Central Western Ghats: Land of local Biodiversity hotspot
Uttar Kannada is the Northern most of the three coastal districts of Karnataka state namely – Mangalore, Udupi and Uttar Kannada. Uttar Kannada is one of the least populated districts of the state. According to the census of India 2001 Karnataka had a population of 52,850,562 of which 1,353,644 comes from Uttar Kannada. The district extends north south to a maximum of 180 km. and west- east to a maximum of 110 km. Lying between 13o55’ -15o32’ N latitude and 74o 05’- 75o 05’south longitude the districts covers an area of about 10,291 sq. km. of which 6502 sq.km comes under dense forest and 1305 sq.km comes under open forest. (State of forest report – 2001).75.86 % of the district is covered by forest which makes it the richest forest district of Karnataka. The district boasts of its 140 km of coast line (which is the most populated part of the district) which is also producer of large amount of coconuts. Of the five National Park and twenty-one Sanctuaries present in Karnataka, Uttar Kannada has three of them respectively, namely- Anshi National Park (250 sq.km), Dandeli Wild life sanctuary (475.02 sq.km) and Attiveri Bird Sanctuary (2.23. sq.km). The district is blessed with large number of Perennial Rivers and many small seasonal hill streams which make the fresh water supply to the district apart from being home to many of the aquatic organisms like diatoms, fishes, bivalves, and crabs etc. which make the livelihood of a large proportion of the coastal population. Kali, Gangavati-Bedthi, Aghanashini and Sharavathi are the west flowing rivers perennial rivers of Uttar Kannada which merge in Arabian Sea while Varada River flows eastwards and joins the Tunga River. Sixty percent of the Western Ghats (one of the 34 biological hotspots of the world) – lies in Karnataka of which a large chunk is situated in Uttar Kannada District. Sreekantha et al (2007) reported two new species of fish from the genus Schistura Mcclelland in the southern most river (Sharavati) of the district. The tropical climate of Uttar Kannada has well defined monsoon period from June to October. The few localities towards coast line experience annual precipitation of 500 cm while the eastern parts may have the precipitation just above 100 cm with the average rainfall over the district being 250 cm. The winters are not that severe but summers are dry and very humid.
The primary cause of the decay of biological diversity in Uttar Kannada is the habitat destruction that inevitably resulted from the expansion of human population and human activities. Bombay gazetteer (1883) mentions of more or less dense forest growth in the hill tops, slopes and many of the Karwar valleys. The best forests were on the slopes and in the valleys facing the Kali river. However large areas of coastal forests have vanished with remnants of scrub lands. Little interior hills are covered with highly disturbed stunted deciduous forests revealing their massive exploitation by industries. Huge mangrove areas which had earlier covered the Kali estuarine areas and backwaters until Kadra or even further are now isolated in small patches except in some areas such as Kanasgeri, Asnoti and Hankon. Hankon has one of the finest and large mangrove vegetation with large trees of Sonneratia ceseolaris and Avicinnia officinalis reaching a height of 15 m. Mangroves are extremely important breeding grounds and feeding areas for shrimp and fish. Despite their great economic value, mangroves are often cleared for rice cultivation and commercial shrimp and prawn hatcheries, particularly in South- East Asia, where as much as 15% of the mangrove areas have been removed for aquaculture. Mangroves have also been severely degraded by over collecting wood for fuel, particularly charcoal production, construction poles, and timber through the region. Hence in the face of dwindling mangrove vegetation, and the surrounding forest vegetation, the study on t mangroves and other coastal vegetation focus on biodiversity and conservation aspects of these threatened habitats and their vegetation.
This endeavour focuses on the assessment of the ecological status of flood plains of Kali river basin considering large scale land cover changes in recent times in the region, while highlighting the environmental legislations towards the conservation of ecologically sensitive regions.
2.4 Conservation Endeavour in India
Traditionally India has a long history of conservation that is evident by the fact that India has the longest living civilization which inhabited the earth ever. The nature is worshiped in some form or the other throughout India. The 5000 year old history of civilization is a testimony of the sustainable development being practiced in India. Even legally the first conservation act came as early as 1897- The Indian Fisheries Act, followed by The Indian Forest Act- 1927, The wild life (protection) act -1972, The forest conservation act – 1980 and The Environment (protection) act- 1986. The first ever national park in India was established in the year 1935 in the foothills of Himalaya now known as Corbet National Park. At present India has around 94 national park and around 502 wild life sanctuaries. The wild life protection act (1972) describes the guidelines for declaring an area as a national park or sanctuary. Conservation provisions as per the prevailing acts are listed in table 2.
Table 2: Acts and policies in India for protecting environment and wildlife
Sr. No. |
Act |
Provisions |
1 |
The Wildlife (Conservation) Act, 1972 |
Prohibits hunting of wild animals, their young ones as well as their eggs |
2 |
The Biological Diversity Act, 2002 |
Prior approval needed from National Biodiversity Authority for collection of biological materials occurring in India as well as for its commercial utilization. |
3 |
Forest (Conservation) Act, 1980 |
Without the permission of the Central government, no State government or any other authority can :
|
4 |
Water (Control and Prevention of Pollution) Act, 1974 |
It is based on the “Polluter pays” principle. The Pollution Control Boards performs the following functions :
|
5 |
Wetlands (Conservation and Management) Rules, 2008 |
Prohibited Activities
Regulated activities
|
6 |
Declaration of Coastal stretches as “CRZ”, 1991 |
Prohibited activities :
|
7 |
National Environment Policy, 2006 |
The principal objectives of NEP includes :
|
8 |
Eco – sensitive zones |
Industries shall be located only with in the Industrial estates and strictly as per the guidelines issued by the concerned state government. |
9 |
The Environment (Protection) Act, 1986 |
Lays down standards for the quality of environment in its various aspects. |
10 |
National Water Policy, 2002 |
Water is a scarce and precious national resource and requires to be conserved and management. |
As a follow up to the Convention on Biological Diversity (1993) to which India is a party among 180 odd nations, Government of India passed Biological Diversity Act 2002. Under this act every local body- a municipality or Gram Panchayat needs to have a Biodiversity management committee (BMC) which is supposed to maintain people’s biodiversity register (PBR) enlisting all the species of that area. This will help in making the biodiversity data base at the grass root level (http://wgbis.ces.iisc.ernet.in/biodiversity/sahyadri_enews/newsletter/issue15/index.htm).
Biosphere reserves: The programme of Biosphere Reserve was initiated under the 'Man & Biosphere' (MAB) programme by UNESCO in 1971. Biosphere Reserves are areas of terrestrial and coastal ecosystems promoting solutions to reconcile the conservation of biodiversity with its sustainable use. They are internationally recognized, nominated by National Governments and remain under sovereign jurisdiction of the states where they are located. Biosphere Reserves serve in some ways as 'living laboratories' for testing out and demonstrating integrated management of land, water and biodiversity (http://wgbis.ces.iisc.ernet.in/biodiversity/sdev/index.htm, UNESCO, 2005., IUCN, 1979). As of today 531 biosphere reserves have been setup in 105 countries all over the world of which 14 fall in Indian Territory. Each Biosphere Reserve is intended to fulfill three basic functions, which are complementary and mutually reinforcing a conservation function (to contribute to the conservation of landscapes, ecosystems, species and genetic variation), a development function - to foster economic and human development which is socio-culturally and ecologically sustainable, a logistic function - to provide support for research, monitoring, education and information exchange related to local, national and global issues of conservation and development (UNESCO, 2005; http://ces.iisc.ernet.in/envis/sdev/bios.htm)
Some of the international treaties which are obligatory pertaining to ecologically fragile regions
Ramsar Convention : Under the convention on wetlands (Ramsar, Iran – 1971) interest was shown by many nations in protecting the wetland ecosystem of high conservation value. As of January 2008, there are 25 Ramsar Sites in India covering 6, 77,131 ha. 135 potential sites were identified in India which can be declared as Ramsar sites. (Islam and Rahamani, 2008)
IBA : The selection of Important Bird Areas (IBAs) has been a particularly effective way of identifying conservation priorities. IBAs are the programme initiated by Bird Life International. IBAs are key sites for conservation – small enough to be conserved in their entirety and often already part of a protected-area network, if significant numbers of one or more globally threatened species of birds, are one of a set of sites that together hold a suite of restricted-range species or biome-restricted species and have exceptionally large numbers of migratory or congregatory species. A site is recognized as an IBA, based on the occurrence of key bird species that are vulnerable to global extinction or whose populations are otherwise irreplaceable. An IBA must be amenable to conservation action and management. Of the 466 IBAs in India, 435 support globally threatened species, 208 have restricted range species, and 123 have biome restricted species, while 141 qualify as IBAs because they hold large congregations of water birds or migratory birds.