About the HIMOM project (running from 2002-2005)
Jacco Kromkamp and Rodney Forster at NIOO-CEME
We are developing a system of Hierarchical Monitoring
Methods for use in European estuaries

This toolkit includes calibrated methods for measuring
sediment properties such as microalgal biomass and
photosynthesis
We are using remote sensing to estimate primary production of
estuaries around the North Sea
We work together with DIVPROD to quantify ecosystem
function and microphytobenthic activity on intertidal flats of the
Westerschelde estuary

A model has been developed to provide accurate
estimates of daily primary productivity at each of the DIVPROD
collection sites
A detailed sediment optical model lies behind the
primary Irradiance
production
calculations
(relative units)
0
20
40
60
80
0
10
Depth (um)
20
30
40
Benthic chlorophyll concentration in upper 1 cm up to 10 000 mg m-3
50
Highest natural phytoplankton concentrations 250 mg m-3
60
Forster & Kromkamp 2004
100
High resolution primary production model
(1) Light and temperature at
the sediment surface
35
25
1000
800
20
15
600
400
10
200
0
0:00 12:00
Chl a (mg g-1 dw)
30
0
PAR
0:00
12:00
200
300
Irradiance (mmol photon m-2 s-1)
0
100
200
300
400
500
600
700
800
900
1000
0
400
500
600
100
0.01
200
300
5
0:00 12:00
100
(3) Vertical profile of irradiance in the
first 1mm of the sediment
4) Irradiance-depth
400
Depth (mm)
1) PAR / SST - time
Depth (mm)
PAR
1400
1200
Temperature
1600
(2) Vertical profile of microalgae
chlorophyll with depth
3) Chl-depth
0.1
500
600
1
700
10
1000
800
0
0:00
900
06:30
Temperature
07:30
08:30
09:30
10:30
(4) Site-specific photosynthetic
parameters are measured in the lab
during each sampling event
11:30
'11:30'
'9:30'
Photosynthetic rate (mg C m-2 h-1)
Pmax
0.0
alpha
0
200
400
alpha
Depth (mm)
17
/0
5
Pmax
0.009
0.008
0.007
0.006
0.005
0.004
0.003
0.002
0.001
0
14
12
10
8
6
4
2
0
/2
00
19
3
/
10
19 05/
:0
/0 20
0
19 5/ 03
/0 20 1
5/ 03 0:
20 1 00
21
03 2:
/0
1 15
5/
20 5:00
26
03
/
13
26 05/
:1
/0 20
0
5/ 03
20 0
28
03 6:
0
/0
10 0
28 5/
:3
/0 20
0
5/ 03
20 0
03 6:
11 00
:4
5
-1
-1
(mg C mg chl a h )
14C photosynthetron
600
800
1000
1200
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Photosynthetic rate (mg C m-2 h-1)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0
Σt Σz P
200
400
Depth (mm)
Photosynthetic rates are
integrated over depth and
time
600
to obtain daily gross
primary production
(units: g C m-2 d-1)
Gross primary production (mg C m-2 day-1)
800
2500
1000
1200
2000
09-2003
sampling
1500
1000
500
0
Dec-02
Jan-03
Mar-03
May-03
Jun-03
Aug-03
Oct-03
Nov-03
Daily primary production per unit biomass shows a linear
relationship with light availability
35
y = 0.88x
MPB
30
-1
gC g chl a day
-1
25
20
y = 0.4x
15
phytoplankton
10
5
0
0
10
20
30
40
50
Quanta (mol m-2 day-1)
Light use efficiency of MPB is higher than that of
phytoplankton
60
70
80
CASI chlorophyll distribution of the Molenplaat