Ecorestoration of Banni Grassland - Global Restoration Network

1. INTRODUCTION
Man’s relationship with his environment is a complex
one. Primitive man managed to live as part of
the natural ecosystem without altering its major
characteristics. However, with the beginning of
agriculture, man became increasingly sophisticated
in his knowledge to modify an ecosystem in order
to obtain the food, fodder or other eco-services he
needed. In achieving this end, man has modified
ecosystems by directing energy and materials from
the system to serve his personnel needs without
due considerations to the overall sustainability of
the ecosystem. As a result, in many managed ecosystems
signs of severe degradation and declining
potentialities in supporting the life forms are becoming
prominent.
Amongst the many ecosystems, grassland is one
of the most affected system, which is clearly evident
by sharp decline in its productivity and species
diversity. The preeminent causes, which induce
the grassland degradation include; overgrazing,
soil erosion, nutrient depletion, salinization,
pollution, disruption of hydrological systems, conversion
of natural areas into croplands, monoculture
plantations and ill-planned developmental
activities. The environmental problems of grassland
ecosystem are so enmeshed that it is very difficult
to resolve which component, is threatening
the sustainability of human life dependent on this
ecosystem. To check the cycle of environmental
decline, non-sustainable land use and socio-economic
instability of the area must be regulated and
efforts to restore the areas of acute degradation’as
well as partially damaged grassland ecosystems are
very essential. Therefore, it is an urgent prerequisite
to develop an over-arching policy to conserve
and manage the grassland resources in a sustainable
manner. This would help in arresting the loss
of biological diversity.
1.1 Grassland / Savanna
Grassland vegetation differs from forests in that
the aboveground vegetation is completely renewed
each year. Grassland is a landscape unit dominated
Ecorestoration of
Banni Grassland
by grasses (Coupland 1978, Yadava and Singh 1986).
These grasses, belong to the family Poaceae
(Graminae), which forms fourth-largest family
amongst the flowering plant, and constitutes over
10,000 species belonging to 700 genera. On the other
hand, Savanna are tropical or near tropical seasonal
ecosystems with a continuous herbaceous layer,
usually dominated by grasses / sedges and a
discontinuous layer of trees and / or shrubs (Frost
et al. 1986).Since the vegetative productivity of
grasses is very high, herbivorous animals,
especially large mammals, are favoured in the
grassland community (Renner 1938). The best
pastures are those in which grazing animals do not
consume more than 70 to 80 per cent total herbage
productivity of the grasses (Stoddart and Smith
1943). Looking at the physiology of grasses, the
meristematic tissue of a grass leaf lies at its base,
when the terminal portion is eaten off, it keeps on
growing. Actually, grazing stimulates lateral
branching at the base of the stem. Therefore, light
to moderate grazing is always good for maintaining
the grassland. However, heavy grazing should not
be permitted, which in turn destroys seed stocks
prior to dropping of the seeds or weaken the plant
physiologically and inhibiting the seed production.
Further, overgrazing produces a change in the kind
and number of animals present. Increased
populations of insects and rodents are a result, not
a cause, of overgrazing.
Savanna is highly dynamic on temporal and spatial
scales, and varies with changes in climate, primarily
rainfall, soil nutrient content, fire regime and
herbivory (Walker 1987 and Skarpe 1991). Grasslands
are evolved under a system of grazing,
drought and periodic fire (Anderson 1982). Either
of these or a combination of all these factors maintain
all the existing grasslands.
1.2 Importance of Grasslands
Mankind is sustained more by grasses than by any
other group of plants. The relationship between
man and grasses dates back to Paleolithic time
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