52
-10
0
20
4O
5 6 0
e,
"~
0
--- -10
~
c~ 20
40
60
80
0,
Lauffen = ,/,~
2
4
6
8
at
Elsenz
0
2
4
6
8
-101
0i
20F
40~
60
801.
10 0
-lof
0~o
201
10 0
;
a. Neckar River
not
measured
Kochendorf
2 4
6
8
b. tributaries
Inn9
.>
Erlz tw m 9
|
2 4
6
8
Br" (gM)
I
20 !
I
i
60|
80
10 0
201
I
!
4OI
I
I
6OI
I
80[
10 0
till
I
,It
Wieblingen
9 B It
2
4
6
8 10
Schwarzbach
2 4
6
8 10
Fig. 4.22. Bromide in the porewaters of the Neckar River and its tributaries
compounds in the algae is unknown. Since many volatile halogenatal organic
compounds exhibit antibiotic properties, one can speculate that these chemicals may
be involved in epiphytic control.
No data at all could be found for freshwater phytoplankton, which is believed to
make up an essential portion of the organic matter in the sediments. For grass and
clover, 17-119 and 19-52 mg/kg were reported, respectively (Kabata-Pendias and
Pendias 1984). However, these values should be considered with utmost care, since no
clear differentiation between water-soluble and -insoluble Br has been made.
Gschwend et al. (1985) believed that there is no known major mechanisms for the
removal of organn 9
from sea water other than exchange with atmosphere. The
result in the study area reveals that sediments act both as sinks and sources for Br. Br"