Geoenvironment Management and Sustainability - Sustainable Practices in Geoenvironmental Engineering - page 20

Reference SFI at outset of
projected or planned service life

Region of enhanced or improved SFI
reflective of improved soil functionality

Region of degraded or diminished
SFI reflective of degradation of
soil functionality

Example of SFI variation due
to impact of stressors over
time of planned service life

Duration in service life

0

Length of time in planned service life

FIGURE 1.7
Example of time- SFI variation for an imaginary planned service project. Over the course of the planned
service life shown on the abscissa, the SFI shows some level of degradation. (Adapted from Yong, R.N. et al.,
Environmental Soil Properties and Behaviour , CRC Press, Boca Raton, FL, 435 pp., 2012.)

human health, and preservation or improvement of habitats and biodiversity. Soil qual-
ity indicators can range from complex and involved techniques using microorganisms as
indicators of soil health, to more simple ones such as the use of soil color to determine the
soil constituents or components, the water content and water logging status of soil.
In the case of geoenvironmental engineering, soil contamination by pollutants and
toxicants and land settlement and subsidence by overburden pressure from constructed
facilities and excess withdrawal of groundwater are of signiicant concern. Indicators are
used to monitor the status of soils threatened by pollutants and toxicants and by ground
subsidence. These indicators are used as signals to inform the stakeholder that the system
is functioning well or to alert the stakeholder to potential problems. An example of the use
of certain soil attributes as indicators is shown in Figure 1.8.

1.4.2 Impacts on Water and Water Resources

It has been suggested by many that, in the future, conlicts among various groups, factions,
and jurisdictions will arise over drinking water and its availability. We need only consider
the availability and distribution of drinking water in the world to see that this sugges-
tion has substance, as shown in Figure 1.9. Less than 5% of the global water is nonsaline
water. Of this less than 5% nonsaline water, it is estimated that about 0.2% of the nonsaline
water is contained in lakes and rivers, with the remaining proportion existing as snow,
ice, wetlands, and groundwater (adapted from Yong, 2001). Values reported much earlier
by Leopold (1974) give numbers such as 2.7% of total volume of water (i.e., global water)
as freshwater, and of that freshwater, it was estimated by Leopold that about 0.36% was
“easily accessible.” Figure 3.1 in Chapter 3 provides a more descriptive illustration of the
distribution of readily accessible freshwater.