Italy - The Lagoon of Venice
349
Macroalgal biomass
a
14
___________________ 1_ ~ ~I~: _ J _______________________ _
:E 12
0)
' w 10
~
8
'ii
~
6
1:
4
- t:D 2
~
o +-----+-----+-~~~--~~~~~ . . __ ~~~~----~--Feb-8S
Apr .. 85
Jun .. 85
Aug-aS
Oct-as
Dec-as
Feb·S6
Apr-a6
Jun-SS
--Alberonl(A)
- - Sacca Sessola (B)
- - 0 - - San Giuliano (e)
20 I-~-- -------------------------------------------------:: ~-~-- -~~~~~~~~~~~~~~~~~~~~~~--~~~~~~~~~~~~~~~~~~~~~~~~--~~
5
- - -- ------------------- - - - - - - - - - - - - - - - - - - - - - -
o
ii'i~JJ@~
Feb .. Apr- Jun- Aug- Oct- Oac- Feb- Apr- Jun- Aug- Oct .. Oec- Feb- Apr- Jun- Aug89
89
89
89
89
89
90
90
90
90
90
90
91
91
91
91
b
Alberoni
~ 1400 ------------- - - - "2114- ..... -
_____ Ulva
0) 1200
-----------------------'iii 1000
- t r - - Enteromorpha
3:
-----------------------(j) 800
- - -- -------------------.!.
600
------------------- -------------------400
1: 200
-
0
0)
Feb- Apr- Jun- Aug- Oct- oec- Feb- Apr- Jun- Aug- Oct- Oec- Feb- Apr- Jun .. Jul89
89
89
89
89
89
90
90
90
90
90
90
91
91
.1
91
Alberoni
:E 1400
0) 1200
'iii 1000
3: 800
1
600
400
... 200
E
-
0
0)
Feb- Apr- Jun- Aug- Oct- Dec- Feb- Apr- Jun .. Aug- Oct .. Oac- Feb- Apr- Jun- Jul·
8.
89
89
89
89
89
90
90
90
90
90
90
91
91
91
91
Fig. 15_2_ a Annual biomass trends at some stations of the lagoon, b Annual biomass
trends of the main species (contributing more than 1% of the total production) sampled
at Alberoni station