Our Environment - Mining and the Environment: From Ore to Metal - page 300

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Quality or beauty of the landscape, sometimes termed 'visual amenity' also deserves
to be assessed in terms comparable to those used for other resources. Perception of
the landscape depends on the sensitivity, conditioning and attitudes of the observer,
educational or cultural conditions, and the relationship between the observer and the
observed object. A mine, for example, will be perceived as beautiful by a mining engi-
neer but as an eyesore by some environmentalists. Also, although the landscape compo-
nents and their relations with the surrounding environment can be described in terms
of design, size, shape, colour, and space, many different considerations may be involved
in assessing the relative value of each and its weight in the total composition.

Perception of the landscape
depends on the sensitivity,
conditioning and attitudes of the
observer, educational or cultural
conditions, and the relationship
between the observer and the
observed object.

For most of us, of course, topography is the most intuitive feature of landform.
Topography influences landscape, but also land stability, land cover, erosion, and sedimen-
tation, as well as the interactions between the solar radiation, water, and the heterogeneous
land surface. The most complex interaction between the biosphere and the climate system
is through the elevational and orographic effects of topography. Topographic structure
strongly influences the regional climate, which controls soil development, water balance,
and vegetation distribution. For hydrological modelling, mine design, and a host of related
activities, detailed mapping of topography is required. The results may be presented
as contour plans, cross-sectional profiles, slope maps, 3-dimensional models, and various
computer-generated images designed to enhance particular topographic features.
In 2000, the US Government sponsored a satellite altimetry of the Earth's surface. The
Shuttle Radar Topography Mission (SRTM) obtained elevation data on a near-global scale
to generate the most complete high-resolution digital topographic database of the Earth.
SRTM consisted of a specially modified radar system that flew onboard the Space Shuttle
Endeavour during an 11-day mission in February of 2000. SRTM is an international
project spearheaded by the US National Geospatial-Intelligence Agency (NGA) and the
US National Aeronautics and Space Administration (NASA). Topographic data are made
available at www2.jpl.nasa.gov/srtm/index.hltm and can be used for regional analysis, with
a horizontal resolution of 90 metres and a vertical accuracy of 15 metres. Higher accuracy
data require stereo-photographic mapping, aircraft laser altimetry, or field surveying.

For hydrological modeling, mine
design, and a host of related
activities, detailed mapping of
topography is required.

Land Cover

Land cover is defined as that which overlies or currently covers the ground including
vegetation, permanent snow and ice fields, water bodies, or man-made structures. Barren
land is also considered a land cover although technically it is lack of cover. Classes of land
cover include built-on land, cultivated land, grassland, wetland, forest, water areas, and
barren land. Each class can be further sub-divided. Forest as an example is sub-divided
according to type of forest (rainforest, wetland forest, mangrove forest, etc.) and/or to
its designated use (production forest, conservation forest, protected forest, etc.). Mining
is seldom permitted in built-on land or other areas with sensitive land cover such as
protected forest, mangrove, or wetlands. As with any rule, however, exceptions do exist
( Case 7.2 ).
An important factor influencing land cover and the productivity of the Earth's various
ecosystems is the nature of their soils, the very upper part of the Earth's crust. Soils are
vital for the existence of many forms of life that have evolved on Earth. Soil itself is very
complex and is much more than merely a combination of fine mineral particles. Soil also
contains air, water, dead organic matter, and various types of living organisms. The forma-
tion of a soil is influenced by organisms, climate, topography, parent material, and time.

Mining is seldom permitted in
built-on land or other areas
with sensitive land cover such as
protected forest, mangrove, or
wetlands.