Our Environment - Mining and the Environment: From Ore to Metal - page 302

TABLE 7.2
Functions of Land - Land quality (or its lack) is not an absolute value, but has to be assessed in relation to land functions and the specifi c land use that one has
in mind

Function Description

Production Land is the basis for many life support systems, through production of biomass that provides food, fodder, fi bre, fuel, timber

and other biotic materials for human use, either directly or through animal husbandry including aquaculture and inland and
coastal fi shery

Biotic environmental Land is the basis of terrestrial biodiversity by providing the biological habitats and gene reserves for plants, animals, and

micro-organisms, above and below ground

Climate regulative Land and its use are a source and sink of greenhouse gases and form a co-determinant of the global energy balance - refl ec-

tion, absorption, and transformation of radiative energy of the sun, and of the global hydrological cycle

Hydrologic Land regulates the storage and fl ow of surface and groundwater resources, and infl uences their quality

Storage Land is a storehouse of raw materials and minerals for human use

Waste and pollution control Land has a receptive, fi ltering, buffering, and transforming function for hazardous compounds

Living space Land provides the physical basis for human settlements, industrial plants, and social activities such as sports and recreation

Archive or heritage Land is a medium to store and protect the evidence of the cultural history of humankind, and source of information on past

climatic conditions and past land uses

Connective space Land provides space for the transport of people, inputs and produce, and for the movement of plants and animals between

discrete areas of natural ecosystems

Source:
FAO (1995)

7.3 THE HYDROSPHERE - STORAGE AND
MOVEMENT OF WATER

For a mining project water may be both friend and foe. Mining project operations invari-
ably require water, sometimes in very large quantities. The uses vary widely: dust suppres-
sion, milling and processing, transport of tailings and/or concentrates, recovery of metals
by leaching, and reclamation of mined lands. Waste waters may be generated from dewa-
tering, runoff from disturbed land, or excess water from tailings impoundments or water
storages. Impacts on the local hydrologic cycle in terms of quantity, quality, or both, often
constitute the most prominent or the most serious environmental impacts associated with
mining.

For a mining project water may
be both friend and foe.

Water in Motion

The hydrologic cycle is a conceptual model that describes the storage and movement of
water between the atmosphere, lithosphere, biosphere, and the hydrosphere. Water on
Earth can be stored in any one of the following media ( Figure 7.4 ): atmosphere, oceans,
surface waters, soils, glaciers, snowfields, and groundwater. Water moves from one
medium to another by way of natural processes such as evaporation, condensation,