Ecorestoration of Banni Grassland - Global Restoration Network

Reversat 1982, Joffre 1987 and Grouzis et al. 1995).
This could be one of the reason for obtaining peak
biomass during September and October in the
unprotected and restoration site where the tree
cover is totally absent while it was in November in
the Prosopis juliflora infested area where dense
canopy of the plant exists. In addition to these, the
grass growing inside shrubby dense thorny bushes
of Prosopis juliflora were inaccessible to the
livestock and this would enable a minimum change
in the biomass between different months and also
produce higher biomass than the unprotected area
during the end of the study period.
At Dhordo restoration site, with the complete absence
of grazing pressure, there was fluctuation of
biomass productivity during different months. The
decrease was due to death and shattering of annual
plants and tillers of perennial grasses following
maturity. The bulk of live vegetation is thus
transferred to standing dead and litters compartments
during the late post monsoon. The same was
also reported by Heady (1960) and Rattiff and
Heady (1962), and they attributed the decline in the
total dry weight of the herbage to approaching dry
season, normal decline following maturity, seed and
leaf shattering, insect and rodent consumption. The
variation in biomass obtained in Dhordo is mainly
due to natural process of drying / dying and or
germination of different grass species due to an
unusual heavy rainfall, received during the month
of September at Dhordo. This created waterlogging
in many areas of restoration and surrounding sites.
As a result, the newly germinated grass plants,
which got submerged under water, died. However,
thereafter, the high moisture availability helped the
viable seeds to germinate and survived or established
grass plant to grow vigorously. This helped
in increasing the biomass during the end of November.
This situation also prevailed in the unprotected
area of Dhordo. As a result, the availability
of grass cover in many parts of Banni distributed
the grazing pressure, and thereby the productivity
showed a slight upward trend in November in the
unprotected area. Though, the recorded biomass
was comparatively less (September and November)
in the Prosopis juliffora area, minimum grazing access
due to the dense coppicing thorny branches
facilitate an overall increase of 17.9 per cent biomass
between September and November.
In the restoration sites, the productivity was found
higher in the unploughed area than that of ploughed
area. In the ploughed area the natural seed bank as
Ecorestoration of
Banni Grassland
well as tillers and rhizome of grass plant were
disturbed due to ploughing activities while in the
unploughed area these were left undamaged.
Therefore, in the unploughed area, few showers
activated the vegetative growth of grass plant from
the tillers or rhizome. In the ploughed area, grass
has to develop from the germination of seeds of
different species sown in that area. The grass seeds
have certain adaptations to survive in the harsh
conditions. All the seeds of a grass plant will not
grow after a single shower. In a single grass plant,
seeds produced in the same spike have different
levels of dormancy (an adaptive mechanism), which
might germinate after it receives a single or multiple
showers. For example, seeds of grass species such
as Cenchrus sp. require certain amount of moisture
to wash the inhibitors present in its seed coat before
germination. This could be the possible reason for
the late recruitment / germination of certain grass
species like Cenchrus sp. in the ploughed area.
Further, after the germination, the plant would take
at least one full season to establish and this may be
an important reason for obtaining more biomass
from unploughed areas than the ploughed areas at
both the restoration sites. However, the fast
recovery due to soil working was evident through
the increased productivity in the ploughed area of
Dhordo and different slopes of Bhirandiyara
restoration sites.
Except Cyperus rotundas and Cressa erotica, which
showed a uniform distribution, other grass species
exercised either random or aggregation. Plant community
is the composition of spatially and temporally
integrated species that retain their individuality
in an area (Mishra, 1968; Mueller-Dombois and
Ellenburg, 1974). Plant communities and associations
characterise the “habitats” in which transformations,
accumulations and flow of energy are involved.
The variation in distribution of different
grass species was caused by several factors like
soil conditions, vegetative propagation, quantity
and dispersal of seeds, grazing, predation by insects,
biotic activities and diseases. In a uniform
vegetation class E is always larger than class D.
However, the situation where E is smaller than class
D denotes eariy stages of succession or severe
biotic influences on the community. Latter process
was recorded on narrow vertical and horizontal
slopes of Bhirandiyara restoration site, which indicates
the successional process in that area.
At Bhirandiyara site, waterlogging is a common
feature during heavy rainfall years. This creates a
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