Environmental Engineering Reference
In-Depth Information
g g
−
1
) of trace elements found in association with particulate matter in the urban aquatic
Table 5.1
Maximum concentrations (
μ
environment
Elements
Pb
Cu
Ni
Zn
Cd
A: Suspended sediment
Lake Ellyn
1
: inlets and outlets
1600
210
nd
950
6
River Sowe
2
719
852
141
1482
33.7
B: Lakes
Wyken Pool
3
476
490
163
1000
29
Swanswell Pool
3
312
292
140
3600
17
Holmer
4
407
51
129
2045
21
Sudbury
3
7700
nd
6200
1400
Nd
Lake Ellyn
1
1750
275
nd
228
Nd
Summer Palace Lake
5
27
27
10
68
Nd
Palace Moat Tokyo
5
320
300
45
1400
Nd
Lake Michigan
5
130
55
30
350
Nd
St John's Lakes
6
600
nd
30
850
2.3
C: Fluvial substrate
River Sowe
2
957
270
843
1586
24.3
River Thame (urban)
7
71
184
117
659
2.5
River Thame (below urban)
7
480
1214
640
3420
24.5
Saddle River
8
200
104.8
22.3
275.1
2.9
R. Rhine
9
369
286
175
1240
13
Manoa Stream
10
1078
300
439
510
1.04
Wyken Brook
3
210
340
800
7000
15
Manzares
11
371
347
47
591
Nd
River Sherbourne
11
134
183
183
817
6.9
D: Wetland
London marsh
12
1180
320
nd
990
20
Wyken
3
1952
300
420
2800
55
Kearney Marsh, New Jersey, USA
13
23.7
11.3
42.7
315
5.25
1
Striegl (1987);
2
Foster & Charlesworth (1996);
3
Charlesworth & Foster (1993);
4
Gaskell (1992);
5
Zhou
et al
. (1989);
6
Christopher
et al.
(1993);
7
Thoms (1987);
8
Wilber & Hunter (1979);
9
Förstner & Müller (1976);
10
Sutherland (2000);
11
De Miguel
et al.
(2005);
12
Zhang
et al.
(1990);
13
Bentivegna
et al.
(2004).
found by Charlesworth & Foster (1993), from
Wyken Slough Marsh, Coventry, UK, which indi-
cates that wetlands can act to mitigate against con-
tamination by acting as a temporary sink. This study
calculated the total stores of Zn and Pb in marsh,
lake, and river sediments, and found that although a
signifi cant amount of contaminants were stored in
the marsh substrate, 12 times as much Pb and nearly
7 times as much Zn was stored in the lake sediments.
Mungur
et al
. (1995) studied the ability of a natural
wetland in northwest London to treat highway
runoff from a main road and found that a combina-
tion of the reduction of water velocity through the
wetland, and interaction with plant stems encour-
aged PAP settlement. Wetland plants also systemi-
cally took up pollutants, but to a limited extent.
Particulates associated with urban activities can
thus be signifi cantly contaminated with toxic metals.
If these should subsequently be deposited on hard
urban surfaces such as pavements and roads, the
likelihood is that they will be washed off during
storms to enter rivers and lakes. The following
section explores the PAP transfer mechanisms unique
to urban environments and how sources of these
