JAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India, 2002
the wetland. This results in fertilization and resultant vegetative
characteristic and floral biodiversity of the wetland. Salt waste
area existent in the catchment is the main source of salts to Nal
Table 5: Structural components, surrounding land use and their
importance for avi-fauna
Sarovar, which are deposited along with the runoff during Component Importance
monsoon. Due to progressive evaporation from the wetland the Open Water Feeding habitat for waterfowls and resting
wetland changes from fresh water to brackish to alkaline. value for ‘swimming’ waterfowl, boating
for tourism and transportation, fishing,
Table 4: Land use of Nal Sarovar Catchment irrigation and drinking, material for local
Land use class | Area (ha) { % to total people, buffer against rain/storm water
Catchment runoff and flooding of local rivers, abode
Agricultural Land 60079.22 | 81.06 : of submerged vegetation, E
Aquatic Food and cover for marsh inhabiting
Salt waste 11727.87 15.82 ; >
Vegetation waterfowl by emergent vegetation, and
Mud flat 640.09 0.86 food for open water waterfowl by
Grassland 359.82 0.76 submerged vegetation, thatching material
Prosopis juliflora thickets 441.12 0.60 for local people and fodder for their
Tank/pond 506.32 0.68 livestock.
Settlement 163.54 0.22 Islet/plateau Resting and roosting value for waterfowls,
SUB-TOTAL 74117.98 grazing of the livestock of local people.
Wetland Edges of the islets also provide feeding
Open Water 8189.09 47.56 opportunity to shorebirds.
Ag. vegetation 514.94 2.99 Shoreline/ Habitat for waterfowls like shorebirds and
Mud flat 6923.53 40.21 Basin cranes, grazing by livestock and
Barren islets 383.00 2.22 recreational activity of tourists.
Vegetated islets 74.32 0.43 Agricultural Feeding ground for migratory cranes,
Salt waste 1032.33 5.99 land in the | agriculture and grazing activity by man.
Agriculture . 103.69 0.60 environs
SUB-TOTAL 17220.90 Wetlands in Secondary habitat for waterfowls and
TOTAL 91338.88 environs Water needs of villages.
Others No direct value to waterfowls but has
Nal Sarovar catchment contains a significant area under
ponds/tanks, which act as satellite wetlands and provide
alternate habitats for waterfowl. À total of 37 such wetlands are
present in its catchment. This is also one of the major reasons
for rich faunal diversity of Nal Sarovar.
5. CONCLUSIONS
No quantitative study of biodiversity involving all its ecological
facets has been carried out for the Nal Sarovar. According to a
study carried out by Gujarat Ecological Education and Research
Foundation (Anon., 1998), Nal Sarovar harbours 74 species of
flowering plants, 48 species of algae and 226 species of birds.
In addition to this, 13 species of mammals, 11 species of
reptiles and large number of insects, zooplanktons etc. are also
found in Nal Sarovar making it a very high biodiversity
wetland.
Habitat types and their temporal variations are the keystones for
biodiversity conservation in wetlands. Present study has shown
the utility of satellite data in mapping and monitoring of
wetlands structural components/habitat types. These features
determine the suitability of wetlands as habitats for waterfowl.
As for example, Tatu (1995) has given details of structural
components and their importance for Nal Sarovar (Table 5).
As mentioned elsewhere, biodiversity of wetlands is a function
of habitat types, its connectivity to the similar habitats in the
vicinity and land use characteristics of the catchment.
Catchment plays a major role in maintaining the characteristics
of habitat types existing within a wetland ecosystem. The
information on structural components and land use generated
using remote sensing data in conjunction with on site data can
be used for biodiversity conservation. A conceptual framework
for wetland biodiversity conservation is given in Fig. 5.
606
ecological/socio-economic importance.
Source: Tatu (1995)
L- RS data | Collateral data |
Wetland
Structural components
Wetland
gradient
N= =n
Habitat types for
Diversity prediction
Habitat types
2 -+2
Species classification
by habitat types using
Species on faxa Biological database
classifications
Diversity o
prediction
BIODIVERSITY ASSESSMENT +]
Fig.5: Conceptual framework for
conservation
wetland biodiversity
The major threat to the Nal Sarovar wetland is the water
availability which is rain dependent and highly erratic leading
to drastic seasonal fluctuations in water level. The economy of
the area is based on agriculture, animal husbandry, fishing and
boating. All these activities generate low income, hence the
people also resort to bird catching, poaching, fishing, boating,
and grazing. These activities coupled with unregulated tourism
are major factors leading to degradation of the fragile
environment of this well-known bird sanctuary. Following steps
are required to be taken to maintain the ecological character,
functioning and biodiversity conservation of the Nal Sarovar:
