3.3 Damage to land and land-use by mining
3.3.1 General effects
The human activities which are instrumental in creating land degradation are mainly deforestation, cultivation, grazing (specially over-grazing), excavation for construction (buildings, roads, etc), disturbing water regime and mining. Mining comes at the end of the list if the land area directly put under mining is considered, but its ancillary activities include all the others (except grazing) in the list, each of which takes active role in the cycle of land degradation (Figure 3.1, after Ghosh, 2000b, pp.272) Cultivation is not an ancillary activity of mining, but, immediately after land acquisition uses of acquired land are to be shifted to a new place. This needs taking new lands under cultivation.

Importance of the subject lies on the fact that mining and its ancillary activities damage not only land but almost all other aspects of environment as summarised next. This is because these either thrive on land or exist in juxtaposition with land.

Air	Gets disturbed by blasting, excavation, transportation and dumping of excavated-out products normally, and specially in dry season by getting the lighter ones blown-up by wind.
Water	Surface water quality and quantity gets disturbed by pouring and siltation of excavated materials and by products of mining and related activities, while ground water(GW) quality and quantity gets disturbed by infiltration and GW withdrawal.
Flora & Fauna	Land-water-forest ecosystem gets disturbed and hence the flora-fauna also.
Aesthetics	Scenic areas are changed into barren depressions and elevations.
Socio- economics	Forest, agriculture and other LUs are disturbed and so the sources of income of the people are also lost.
Culture	No doubt cultural resources are protected from any such disturbance, but the effects on socio-economics, aesthetics and ecosystem may endanger the existence of cultural resources.

3.3.2 Damage by different activities for mining
Impact of mining on land and land use starts at the time of land-acquisition and continues up to use of the mined-out product, as is being detailed next.
Land acquisition and vacating
Immediately after acquisition of a piece of land for mining, the pre-mining uses of the acquired land needs shifting. This may need construction of houses and other facilities for the displaced people, which, in turn, needs a new land, which may cause damage to greenery and require excavation of land. Further, the rehabilitated people try to grow their food at the new site and hence have cultivation on any small piece of available land. All these increase erosion potential of the region which fills up gradually the surface water bodies through siltation . This decreases the irrigation potential of the region. Some of the lands which were probably having two or three crops every year (one rain fed and the others by irrigation) will now have only one crop in monsoon and will remain barren for rest of the year.

Barren lands in dry season get exposed to scorching sun and wind, get further dry (by losing soil moisture), get more prone to erosion and hence get eroded. Water from below water table rises partially through capillary rise to near surface to compensate the soil moisture deficiency and gets evaporated in turn creating loss of GW.

In the next monsoon the surface runoff will carry soil particles (more in quantity than the pre-acquisition days), which will thus increase turbidity and siltation of surface water bodies resulting to decrease in infiltration potential and water holding capacity of these.

The cumulative effect after some years will be loss of fine soil particles (which hold major part of soil nutrients) hence loss of greenery growing potentiality of the region and hence aggravated erosion potential. The land will gradually lose a thin film of soil from its top. In the long run (may be after hundreds of years) the water table also will go down due to loss of capilary water through this surface lowered due to erosion. The process will run increasingly in a more aggravated speed and push the land gradually towards degradation and lastly desertification. The total process is given in Fig. 3.2 (after Ghosh 2002).

As all the pre-acquisition land-uses get shifted from the acquired land, the quality of all environmental attributes including the societal conditions and the quality of life of the people living there gets disturbed.

Clearing the vegetation cover
Mining needs clearing the acquired land which in most cases need removing its green cover, or even deforestation in some cases, which invites land degradation as detailed in Fig. 3.1 and 3.2. Among the odd activities required for mining, the most prominent, effective, inevitable activity is, while its long-term effects, i.e. damage to greenery land degradation and desertification are indirect, and hence, to some extent intangible, these produce most serious effect on land. Utilities of greenery in preventing land degradation has been detailed in section 3.3.4.

Excavation
Impact of mining on land, due to excavation depends upon the type of mining. Broadly there can be two types of mining depending upon the depth of the deposit to be mined, namely surface (OC) mining and underground (UG) mining. Examples of OC mining are the Kudremukh iron ore mines in Western Ghat region of Karnataka, Noamundi iron ore mines in Bihar, Jhamarkotra phosphorite mine in Udaipur, Rajasthan, many coal quarries in Raniganj coalfield (RCF) and Jharia coal field (JCF) etc.

There may be broadly two types of OC mining depending upon terrain conditions, these are "area strip mining" and "contour strip mining". Contour strip mining refers to the method which exploits the minerals by excavating along the contour lines on hill slopes or mountains while area strip mining is the method applied on rather flattish terrains. Further, UG mining can be of different types depending upon the characteristics of the deposit specially its mode of occurrence. Each of the varieties of mining are hence being considered separately.

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