Section 3 of the Environment (Protection) Act 1986 (EPA) gives power to the Central Government i.e. the Union Ministry of Environment and Forests to take all measures that it feels are necessary for protecting and improving the quality of the environment and to prevent and control environmental pollution. To meet this objective, the Central Government can restrict areas in which any industries, operations or processes or class of industries, operations or processes shall not be carried out or shall be carried out subject to certain safeguards.thus the government came up with the concept of Eco Sensitive Zones.
ESAs are defined as those areas ‘that are ecologically and economically important, but vulnerable even to mild disturbances, and hence demand careful management’. Therefore ‘ecologically and economically important’ areas are those areas that are biologically and ecologically ‘rich’, ‘valuable’ and or ‘unique’, and are largely irreplaceable if destroyed. Further, by virtue of their biological richness, they could be potentially of high value to human societies, help in maintaining the ecological stability of the area, and be significant in conserving biological diversity. Similarly, their ‘uniqueness’ may be recognized either by the rarity of the living systems they harbour, that are difficult to replace if lost, or by the uniqueness of the services they offer to human society. Their ‘vulnerability’ could be determined by physiographic features that are prone to erosion or degradation under human and other influences such as erratic climate, and on the basis of historical experience.
Criteria for demarcating ESAs
There are three important categories of attributes that need to be considered in defining the ecological salience/significance/sensitivity of an area: physico-climatic features (geo-climatic features), biological features and social relevance (including cultural, economic and historical importance) of the area. All these may be grouped as (a) abiotic attributes, (b) biotic attributes and (c) anthropological or socio-cultural attributes.
Biological attributes: The demarcation of an ESA shall consider the following components of biological and cultural uniqueness and richness.
• Biodiversity richness: Richness in diversity for all taxonomic groups and hierarchies.
• Species rarity: Rarity in terms of population size, extent of geographical distribution, and also rarity in taxonomic representation in terms of paucity of closely related taxa.
• Habitat richness: Spatial heterogeneity of landscape elements.
• Productivity: Total biomass productivity.
• Estimate of ecological resilience: Level of persistence of original climax vegetation.
• Cultural and historical significance: Evolutionary– historical value and cultural–historical value of the area.
Geo-climatic layers attributes: These include layers that permit assessment of the innate or natural vulnerability of the area. Obviously features such as slope, aspect, altitude, precipitation, etc. shall be used under the following component attributes:
• Topographic features: Slope, altitude, aspect, etc.
• Climatic features: Precipitation, number of wet days, etc.
• Hazard vulnerability: Natural hazards such as landslides and fires.
Stakeholders’ valuation: It is important to take on board perceptions of the civil society and local bodies, especially the zilla, taluk and gram panchayats, to decide on areas that they consider to be ecologically and environmentally sensitive. Of course, these perceptions will depend on the proposed management regime.