Sirish A. Ravan
Research Scientist, MRSAC, VRCE Campus
South Ambazari Road, Nagpur
Email: [email protected]
Depiction of ecosystem harbouring around 120,000 known plants and perhaps another 400,000 as yet undescribed species of plants, microbes and animals is possible with the recent technological advances.
Biodiversity is receiving the attention of various scientists/planners/decision-makers due to its importance as a natural reservoir with tremendous economic potential. Conservationists have focussed attention on this fast depleting resource. In-situ conservation using ecosystem approach is popular which also protects various ecological services offered by forest ecosystem. Examples of such services are soil and water conservation, pollutant sink, noise reduction, shelter belts, microclimatic effects etc. Emphasis is on identifying most valuable biodiversity spots that harbour non-timber forest species such as endangered flora and fauna, medicinal plants and wild relatives of cultivated crops. While identifying such spots, it is also important to take into account the landuse and human activities around the forest.
Conservation programmes for the 21stcentury are increasingly focused at the ecosystem level. IUCN/UNEP/WWF observe that “conserving biological diversity equals conserving ecosystems”. The key question in this case is “Where are such ecosystems and how one is important in comparison to another?”
Comprehensive, quality information on the distribution, status and utilisation of India’s biodiversity is the cornerstone for planning its conservation. While a lot of information exists, it is dispersed widely across the subcontinent among a large number of organisations. Moreover, some of it is not easily accessible or available in readily usable electronic form. Also, there are significant gaps in database in many areas.
Hence, assessing biodiversity of megadiversity country like India is enormous task. Depiction of ecosystem harbouring around 120,000 known plants and perhaps another 400,000 as yet undescribed species of plants, microbes and animals is possible with the recent technological advances. Over the years, scientists have tried to find practical and simplified approaches to identify vegetation unit that represents unique species composition and diversity. Thus, the term “vegetation type” became popular among ecologists, which can be defined as ‘the assemblage of dominant growth forms of plant species sharing common habitat i.e. landform.
In early 90’s, the efforts were focussed on supplementing field-based observations with the remote sensing based observations. The challenge was to prove that units identified on remote sensing data represents unique composition. In pioneer studies carried out at Indian Institute of Remote Sensing, Dehradun, vegetation communities in dry deciduous forests were mapped using Landsat TM data. Field data collected using stratified random sampling was analysed statistically to identify communities existing in the forest. The results showed vegetation units identified on remote sensing image show total agreement with the results of field based observations (Ravan, Roy and Sharma, 1995). The advantage of remote sensing is that it also identifies the vegetation /landuse units which may likely to miss during field surveys because of limitations in sampling techniques.
Recent publications from Centre for Ecological Sciences (Indian Institute of Science) have verified above concept in Western Ghats forest by classifying ecological entities differentiated in terms of their composition/configuration to which field investigations of biodiversity can be linked (Nagendra and Gadgil, 1999). Thus, the efforts have resulted in wide acceptance of remote sensing technology in various studies such as wildlife ecology, biodiversity assessment, wetland ecology, biodiversity prioritization, forest and wildlife management etc.
The technology that has given many more dimensions to the applicability of remote sensing based vegetation type map is ‘Geographic Information System (GIS)’. To name one, Landscape Ecology is benefited most with the availability of spatial analysis tool like GIS.
Landscape ecology considers vegetation as a mosaic of patches of vegetation with unique landform, species composition and disturbance gradient and focuses on parameters such as patch sizes, patch shapes, patch isolation, interspersion (adjacency of various landuses/landcover), juxtaposition (relative importance of adjacent patches), fragmentation, patchiness etc. All these parameters have direct bearing on the status of biodiversity within forest ecosystem.
Spatial analytical capabilities of GIS allow quantifying all above parameters with the remote sensing based vegetation type map alone. Roy et al, 1996 have used GIS to characterise habitat of endangered animal, Mountain Goral, using GIS for evaluating principles of landscape ecology. Ravan and Roy, 1998 have again proved potential of GIS in landscape ecology by mapping disturbance zones in natural ecosystem and quantifying its impact on the biodiversity and biomass accumulation along the disturbance gradient. GIS was used in this study for quantifying patch sizes, shapes, porosity and patchiness of vegetation types. GIS was also used to extrapolate results of ground based estimations such as species richness, diversity index and biomass values.
The results of above studies have assured the success in identifying bioprospecting zones for conservation prioritization at regional level by making use of GIS, remote sensing and landscape ecology. With the initiatives of Department of Space and Department of Biotechnology, the concept of Landscape Ecology is being verified in the biodiversity hot-spots of Western Ghats and Himalayas.
GIS technology, besides its contribution in scientific studies, has been accepted as the most effective tool for decision-makers. Maharashtra Forest Department, under the leadership of J.S. Grewal (Conservator of Forest) has established GIS for forestry at Nagpur. GIS for forestry at Maharashtra is contributing in 4 different areas such as working plans, biodiversity, village ecodevelopment, and plantation inventory for Forest Development Corporation. Similar efforts have been put in by H.C. Mishra in Andhra Pradesh Forest Department. Many other state governments are also making use of GIS for forest management, the results of such efforts would be visible in near future.
NGO sectors such as World Wide Fund for Nature-India (WWF-India) and Tata Energy Research Institute (TERI) have also stepped in the biodiversity conservation efforts using GIS. WWF-India has already computerised third edition of forest cover maps of FSI in GIS environment. In addition, baseline database on important national parks/sanctuaries are also developed. The attempts have also been made to link taxonomic details of rare and endangered species to GIS database. All these NGOs need the support from the custodians (generally govt. organisations) of primary data on biodiversity.
Many Research Institutes working in the area of biodiversity conservation have started use of GIS technology. Prominent among them is Wildlife Institute of India. Other institutions are G.B. Pant Institute of Himalayan Environment and Development, Centre for Ecological Sciences (Indian Institute of Science), Kerala Forest Research Institute, Gujrat Institute of Desert Ecology etc.
The above trends give impression that Research Institutes, State Forest Departments, Central Government Agencies such as FSI, and NGO Sector can put hands together to save biodiversity, the most valuable resource, of the country.
The huge amount of databases being generated by various organisations needs to be structured for evolving information system for forest management. Such information system is scientific tool for the forest managers to perform better in the area of forest/wildlife management and biodiversity conservation.
| Biodiversity characterisation at landscape level using satellite remote sensing and GIS: A project sponsored by Department of Biotechnology and Department of Space (DOS)
The experiences of the R&D work done at Indian Institute of Remote Sensing, Dehradun has resulted into the nation-wide efforts of identifying the bioprospecting areas for conservation. The objectives of the project are
The project is being executed in the Western Ghats and eastern and western Himalayas. DOS has prepared project manual explaining standard methodology for execution of the project. The project has made landmark contribution in the field of GIS. The software ‘BIO_CAP’ has been customized over Arc/Info GIS and can operate on different standardized databases. It provides facilities for display, overlay, integration, analysis, statistics, modelling of landscape.
Phase I of the project is implemented under coordination of Indian Institute of Remote Sensing, Dehradun. The main organizations involved in the project are Natioanal Remote Sensing Agency, Forest Survey of India, Wildlife Institute of India, G.B. Pant Institute of Himalayan Environment and Development, Botanical Survey of India, French Institute (Pondicherry), Maharashtra Remote Sensing Applications Centre, respective State Forest Departments etc. The contact person is Dr. P.S. Roy, Dean, Indian Institute of Remote Sensing, who is also Project Director.