Geoscience Reference
In-Depth Information
(a)
(b)
1853
North Gare
Sands
Bran
Sands
1972
1881
1953
Seal
Sands
1972
1938
1906
Greatham
Creek
1953
Coatham Sands
1972
Cowpen
Marsh
1974
Bran
Sands
Seal Sands
Redcar
1972
1723
1881
1972
1953
1740-1808
1881
1938
1921
1921
1938
1906
1906
1km
Intertidal land
Middlesborough
(c)
Tees Estuary: land claim
3000
2500
2000
1500
1000
500
Fig. 7.14
The sequential claiming of the Tees estuary, UK:
(a) Tees estuary in the mid-nineteenth century; (b) phases of
subsequent land claim; (c) loss of intertidal area between 1850
and 1900. (Modified from Davidson et al. 1991.)
0
1850
1900
1950
1990
Year
management should be a means of maintaining
a form of
status quo
(i.e. protect what these
systems have become and prevent further human-
induced change), or whether it should be a means
of managing what they once were, i.e. to regain
a natural estuary or delta. The latter is imprac-
tical in many situations owing to the extent to
which humans have developed and interfered with
natural functioning. The former is perhaps the
most workable, but the issue then becomes what
to take as the
status quo
. This debate becomes
complicated. For example, the Nile delta is still
changing in response to the construction of the
Aswan High Dam, so do managers wait until
it has stabilized, or begin to manage the area as
it is at the present time, given that the current
situation is only a snap-shot representing one
short section of the conveyor belt of gradual
adjustment and change?
The key debate here is the idea of conserving
or preserving. Natural systems need to change
and adapt to changing environmental condi-
tions. Whether such changes are natural or
anthropogenic is, to some extent, unimportant.
