Environmental Engineering Reference
In-Depth Information
simply the chemical environment that is considered, but a healthy ecological
status is also a key objective.
Through changes in legislation there has gradually been an improvement
in the quality of many environmental compartments within the landscape.
However, in many parts of the world, legislation is underdeveloped, or not
sufficiently implemented, resulting in continuing threats to the ecological
health of the receiving environment. In addition continuing advances in tech-
nology result in new pollutants such as those from the nanotechnology and
pharmaceutical industries (
Chapter 5
), and critically the effects of these on
organisms are largely unknown.
The long history of global industrial activity has led to the accumulation
of contaminants within the environment, especially where the pollutants in
question are persistent. It is therefore extremely important that, when con-
sidering the impacts of industry, we also recognise the potential contribution
of these historical sources to the impacts on current ecological communities.
Floodplain deposits, in-river sediments and ancient mine workings are a few
examples where old contamination can still affect present day ecosystems
(
Chapter 2
,
Chapter 13
and
Chapter 14
, respectively).
It is a clear ecological concept that environmental heterogeneity within a
landscape can drive biological diversity (e.g., see Hutchings et al.
2000
), but this
can also be true within polluted environments (
Chapter 2
). The presence of
highly metalliferous soils upon naturally occurring outcrops of metal ores has
led to the adaptation of a number of species (particularly plants, lichens and
bacteria) to these conditions, and indeed some may only survive where metal
concentrations are high. The exploitation of these resources by man has led to
these communities being extremely rare, but they can often survive and prolifer-
ate on abandoned sites. The lead rakes of the Peak District are a prime example
of this, where calminarian grasslands can be found (Barnatt & Penny
2004
).
However, changing environmental legislation, the decline of industrial activity
and potentially also environmental change now pose a significant threat to these
highly biodiverse areas. For example, the requirement to meet the objectives
of the Water Framework Directive may result in the removal or remediation of
metal sources, such as spoil heaps from the environment. A number of different
threats to these unique communities are identified by Baker et al. (
Chapter 2
).
More modern remains of industry are also proving to be valuable as refuges
for threatened species. The move from a manufacturing based economy to one
based largely on service industry within many countries in the developed
world has led to large areas of so-called brownfield land, which are often
contaminated by a mixture of pollutants. The lack of human access, together
with particular environmental conditions has allowed the colonisation of these
areas with a range of species. Although this has not been dealt with in this
volume, readers are directed to
Chapter 3
of Natural England's Report on the
State of the Natural Environment (2008).
