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and organizations for the Western Ghats and west coast
of India, and the information that these maps and tables
contain a specific parameter namely species diversity.
The French Institute of Pondicherry in collaboration
with the Indian Council for Agricultural Research has
published a vegetation map of Peninsular India at a
1:1,000,000 scale. Two sheets of this map, Cape
Comorin and Mysore (Gaussen et al., 1961, 1965) cover
the entire Western Ghats area. Subsequently, the Forest
Map of South India has been brought out, at a 1:250,000
scale (Pascal, 1982, 1986). Maps of the Nilgiri
Biosphere Reserve area have also been made, to a
detailed 1:100,000 scale (Prabhakar and Pascal, 1994).
The classification schemes characterize ecosystems
based on their plant cover, and identify them with the
help of visual interpretation of Landsat MSS and TM,
and SPOT imagery. Fifteen types have been recognized
in the evergreen and semi-evergreen climax forests, and
three types in the deciduous climax forests. Based on a
few field plots, for each of the natural types as well as
some of their degradation stages, detailed floristic lists
are provided (Pascal, 1986). These lists are not
obviously exhaustive - however, for some of the more
natural types where more plots have been laid, they
estimate that they have encountered between 75% and
90% of the species present in that type. However, as no
analysis has been published demonstrating that these
types differ significantly in their species composition, it
is difficult to extrapolate this information to other
mapped areas where no field investigations have been
made.
The Forest Survey of India in collaboration with
the National Remote Sensing Agency of India has
carried out a 1:1,000,000 scale mapping of forest cover
in India several times, the most recent being during
1989-91 (Dutt et al., 1994). Visual interpretation of
Landsat MSS imagery has been used to prepare these
maps. The categories employed are however very few -
closed forest, open/degraded forest, mangrove forest and
non-forest (which encompasses agricultural areas,
barren land and non-forest plantations). Forest
plantations such as Acacia auriculiformis are classified
under the forest categories.
This kind of mapping is obviously not very useful
for assessing species composition or diversity. Flowever,
in 1993-1994, a detailed, 1:25,000 scale classification of
the Western Ghats area into different types of forests -
evergreen, semi-evergreen and deciduous - with varying
levels of canopy cover discriminated - as well as
plantations, crops and other ecosystem types has been
carried out. This map has not been so far published.
The National Remote Sensing Agency has
prepared wasteland maps for several parts of India,
especially those dominated by barren lands. This is
perhaps the only large scale mapping effort in the
Western Ghat region mapping ecosystems that lack
vegetation cover. These maps are at a 1:50,000 scale and
have been prepared using visual interpretation of
Landsat MSS imagery. Thirteen categories are defined
(NRSA, 1991). As is apparent from a look at these
categories, this system of classification combines land
use systems like grazing or shifting cultivation and
physical features such as ravinous lands or upland
characteristics along with ecosystem types such as
agricultural or plantation areas. This set of maps does
not provide information about species diversity.
However, since this classification scheme is created for
the purpose of wasteland reclamation, it would have
been useful if it also provided information on natural
resource parameters such as soil erosion rates, or water
quality in each type. This would permit better
understanding of the different wasteland types, for their
management.
Recently, a more detailed system of classification
for India has been proposed by the Space Applications
Centre under the National (Natural) Resources
Information System (NRIS) (SAC, 1997). This scheme
is recommended for use while mapping India's natural
resources - forests, agricultural areas, wastelands and
cities, and the categories used integrate information
obtained from remote sensing, conventional
cartographic maps as well as non-spatial data on
parameters like demography. The categories are not
suited to natural resource distribution analysis, and
surely not for species diversity analysis. All forest
plantations, for example, are clubbed under one
category. Evergreen as well as semi-evergreen forests
are also combined. They define ‘open’ and ‘closed’
forests, and it is not clear what the delineating line is
between these two, or between open and scrub forests.
Crops, also, are classified as kharif and rabi, depending
on the growing season, rather than based on the species
or set of species grown.
These classification schemes in their present form
do not provide complete data for the management of
natural resources. If these extensive, remote sensing
based maps can be standardized and correlated with the
distribution of natural resources on the ground, then this
will provide a vast store of information which can be
used to plan effective management strategies for
harvesting natural resources.
One such attempt has been carried out by Ramesh
et al. (1997). This provides an elaborate analysis of the
