Produção primária - Tópicos
z Tipos de produtores e taxas de produção
z Medição da produção primária
z Mecanismos – Curvas PI e blooms
z Distribuições e tendências
z Variabilidade e erros de determinação
z Aquecimento global
CO2 + 2H2A
Light
Pigments
CH2O + 2A + H2O
Tipos de produtores
Produtor
Nutrientes
Exemplos
Fitoplâncton
Microfitobentos
Macroalgas (algas macrófitas)
Vegetação de sapal
Angiospérmicas (“seagrasses”)
Coluna de água
Coluna de água
Coluna de água
Sedimento
Sedimento e/ou água
Diatomáceas
Diatomáceas
Fucus
Spartina
Zostera
z Oceano aberto, águas costeiras e estuários
z Unicelulares
z Razão P/B elevada (>50)
z Zonas pouco profundas (Zf > Z) ou intertidais
z Multicelulares
z Razão P/B baixa
Relevância à escala do ecossistema II
Distribuição global de clorofila a estimada a
partir de dados de satélite
Clorofila a
(mg m-3)
Dados do SEAWIFS, Verão no Hemisfério Norte (1998-2001)
Prod. primária (fitoplâncton) 200-360 X 1014 gC ano-1 (98.9%)
Phytoplankton
some examples
Diatoms
Dinoflagellates
Coccoliths
Phytoplankton - diatoms
Nitschia bicapitata
5µm
Chavez et al., 1991 - Limnol. & Oceanog. 36, p. 1816-33
SeaWifs images of
cocollith blooms
Cornwall, U.K.
Tasmania
Relevância para a gestão I
“Bloom” de Noctiluca – California, E.U.A.
Foto cortesia de P.J.S. Franks, WHOI
Cyanobacteria bloom – Potomac estuary
This dense bloom of cyanobacteria (blue-green algae) occurred in the Potomac River
estuary downstream of Washington, D.C. Photo courtesy of W. Bennett USGS.
Relevância para a gestão III
“Bloom” de macroalgas na Florida
Em Florida Bay, este “bloom” de macroalgas colmatou as fanerogâmicas marinhas,
provocando o desaparecimento desta vegetação. Foto cortesia de Brian Lapointe, Harbor
Branch Oceanographic Institute.
Relevância para a gestão II
Advecção de HAB (?) para a costa a partir de uma frente “offshore”
PML Remote Sensing Group
Cortesia Plymouth Marine Laboratory, UK
http://pml.ac.uk/
Multi-sensor discrimination of harmful algal blooms, P. I. Miller, J. D. Shutler, G. F. Moore and S. B. Groom,
Remote Sensing and Photogrammetry Society annual conference RSPSoc 2004, 7-10 September 2004,
Dundee U.K.
Kelp in Sanggou Bay, China
Produtividade de diferentes ecossistemas (kg C m-2 ano-1)
z
Produtores marinhos
Corais
Laminarias
Plantas de sapal
Posidonia
Mangal
Microalgas bentónicas
Fitoplâncton costeiro
Fitoplâncton oceânico
z
Produtores de água
doce
Macrófitas
Fitoplâncton (eutrófico)
Fitoplâncton (oligotrófico)
z
Produtores terrestres
Floresta tropical
Floresta temperada
Pastagens
Pradarias
Desertos, tundra
0
1
2
3
4
Produtividade e biomassa média, taxa de
renovação e clorofila em diferentes ecossistemas
Produtividade
Área
líquida
6
2
(10 km ) (gm-2 ano-1)
Oceano aberto
Afloramento
Plataforma
Macrófitas/recifes
Estuários
332
0.4
27
0.6
1.4
• Total marinho
Biomassa
(kg m-2)
125
500
300
2500
1500
0.003
0.02
0.001
2
1
361
155
0.01
Ecossistemas
terrestres
Pântanos
Lagos e rios
145
737
2
2
3000
400
15
0.02
• Total continental
149
782
12.2
12
Taxa de
renovação
(P/B, ano-1)
Clorofila
(g m-2)
42
25
300
1.3
1.5
0.03
0.3
0.2
2
1
0.05
0.061
0.2
20
0.064
1.54
3
0.2
1.5
Whittaker & Likens, 1975. The Biosphere and Man. Primary productivity of the biosphere.
Springer-Verlag.
Medição da produção primária
Produtor
Medida
Método
Unidades
Fitoplâncton
e microfitobentos
Macroalgas
“Seagrasses”
Sapal
Biomassa
Produção
Biomassa
Produção
Biomassa
Produção
Clorofila a (amostra filtrada)
14C, O (incubação)
2
Cropping
O2 (incubação), cropping
Cropping
O2 (incubação), cropping
µg L-1
d-1
gDW m-2
gC m-2 d-1
gDW m-2
gC m-2 d-1
z Upscaling: SIG, modelação
Saltmarsh definition – NDVI and bathymetry
NDVI = (Near_Infrared - Red) / (Near_Infrared + Red) Near_Infrared e Red são duas bandas da imagem de satélite. O NDVI
situa-se entre -1 e 1. Os pigmentos absorvem grandes quantidades de energia no vermelho (R), e poucas no infravermelho
próximo (NIR), ao contrário dos objectos inertes que absorvem todos os espectros da mesma forma.
Relação entre a taxa de fotosíntese (P) e a
intensidade luminosa (I)
Pmax
I
(qu nitial
ant slo
um pe
yie
ld)
dP
dI
0
PPL
PPB
R
Ic
Ik
Iopt
Phytoplankton blooms and vertical mixing
Production and respiration
0
a
e
NPP=0
b
Depth (z)
Phytoplankton
production (m-3 day-1)
Integrated
respiration
aefd
Compensation depth
Phytoplankton
respiration (m-3 day-1)
d
c
f
Integrated
production(GPP)
abcd
Limit of
mixed layer
Conditions for
blooming
abcd > aefd
Sverdrup, H.U., 1953. On conditions for the vernal blooming of
phytoplankton. J. Cons. Perm. Int. Exp. Mer, 18: 287-295
Phytoplankton blooms in estuaries
Phytoplankton growth: P0 = initial
population, Pt = population at time t
Pt = P0 ekt
Freshwater
inflow Q (m3s-1)
Tidal exchange
with the ocean
Phytoplankton flushing: P0 = initial population, Pm = population
after m tidal cycles, r = exchange ratio (proportion of estuary
water which does not return each tidal cycle)
Pm = P0 (1-r)m
Ketchum (1954) Relation between circulation and planktonic
populations in estuaries. Ecology 35: 191-200
Phytoplankton blooms in estuaries
Combining the two equations
(and expressing t in terms of m):
Growth
Flushing
Pt = P0 ekt
Pm = P0 (1-r)m
Pm = P0 emk(1-r)m
For a steady-state population , Pm = P0 :
1
(1 − r )m
k = -ln(1-r)
= e mk
For phytoplankton to exist and potentially bloom in an
estuary, growth must balance flushing, i.e. k > -ln(1-r)
Phytoplankton blooms in estuaries
Required coefficient of reproduction
Barnstable
Harbour
10
2.0
Population
will increase
5
1.0
Alberni Inlet
Raritan Bay
Population
will decrease
2
Raritan River
Moriches Bay
0
0.5
1.0
Exchange ratio (r)
Redrawn from Ketchum (1954)
Multiplication of population each tidal cycle
20
3.0
CZCS derived sea-surface pigments
Mediterranean Sea
5oW
5oE
0o
10oE
15oE
20oE
25oE
30oE
35oE
45oN
45oN
40oN
40oN
35oN
35oN
30oN
30oN
5oW
0.01
0.03
5oE
0o
0.05
0.10
0.20
10oE
0.30
0.50
15oE
1.00
20oE
25oE
30oE
35oE
3.00
http://www.obs-vlfr.fr/
Chlorophyll a in the Tagus estuary
Hypereutrophic
90
80
70
60
50
High
40
30
20
Medium
Chlorophyll a (µg L-1)
Surface values on a longitudinal section
10
Low
0
0
50
100
150
200
250
300
350
400
Julian day
Data from BarcaWin2000 - Stations #1.0, #2.0, #3.9, #4.0, #5.0 and #8.0 – 385 values
Tidal freshwater zone (1980-1998)
90
Chlorophyll a
trends in the
Tagus estuary
80
70
Hypereutrophic
60
50
40
High
30
20
Medium
Low
10
0
1/01/80
27/09/82
23/06/85
19/03/88
14/12/90
9/09/93
2/03/99
5/06/96
Mixing zone (1980-1999)
90
80
70
Hypereutrophic
60
50
High
40
30
Seawater zone (1980-1999)
90
20
Medium
Low
10
80
70
0
1/01/80
Hypereutrophic
60
27/09/82
50
40
High
30
20
Medium
Low
10
0
1/01/80
27/09/82
23/06/85
19/03/88
14/12/90
9/09/93
5/06/96
2/03/99
23/06/85
19/03/88
14/12/90
9/09/93
5/06/96
2/03/99
OAERRE data + TICOR data
Chlorophyll a and nutrients
Maximum spring phytoplankton (chl a µg L-1)
30
Tejo
GM
25
GF
20
Guadiana
HF
15
10
Sado
FC
KF
5
Mira*1
Mondego
Ria de Aveiro*2
Ria Formosa
0
0
10
20
30
40
50
60
70
80
90
100
110
120
Maximum winter DIN (µM)
Tett, P., Gilpin, L., Svendsen, H., Erlandsson, C.P., Larsson, U., Kratzer, S., Fouilland, E., Janzen, C., Lee, J., Grenz, C.,
Newton, A., Ferreira, J.G., Fernandes, T., Scory, S., 2002. Eutrophication and some European waters of restricted
exchange. Submitted to Coastal and Nearshore Oceanography, NEEA, and unpublished work from TICOR.
*1
*2
– Chlorophyll determined from graphical data
– Nitrate, not DIN
GIS - Chlorophyll a
Composite annual mean
µg l-1 chl a
0
10
20 km
GIS - Mean
chlorophyll a
Winter mean
Winter, summer and
global
Summer mean
0
Data from 19801983, Tagus
estuary, Portugal
10 20 km
µg l-1 chl a
<2
2-3
3-5
5-7
7-8
8-10
10-12
12-15
15-20
>20
Annual mean
0
10 20 km
0
10 20 km
GIS - Comparison between
January and April
chlorophyll a
µg l-1 chl a
<2
2-3
3-5
5-7
7-8
8-10
10-12
12-15
15-20
>20
0
10 20 km
January
0
10 20 km
April
Data from 1980-1983, Tagus estuary, Portugal
GIS - Chlorophyll a
Surface minus bottom
µg l-1 chl a
-1.35- 0
0-0.5
0.5-1
1-2
2-3.5
0
10
20 km
Variação interanual de clorofila a no
estuário do Tejo, durante 4 anos
80
70
Clorofila a (ug l-1)
60
50
40
30
20
10
0
0
365
730
1095
1460
Dias
Dados para a estação #2.0, amostras de superfície colhidas ao longo de 4 anos
Baía de S. Francisco – E.U.A.
Baía de
S. Pablo
Baía de Suisun
Oceano
Pacífico
South
Bay
Anos 70
Década de oitenta
Anos 90
1977
Max: 6.9
1980
8
7
6
5
4
3
2
1
0
60
1978
Max: 6.9
5
1982
50
Max: 50.6
10
0
14
1987
12
10
Max: 12.3
6
4
100
200
300
1989
0
25
1998
100
Max: 53.2
20
0
120
1999
20
15
60
400
Max: 16.2
30
10
Max: 113.3
40
0
1984
50
2
80
Max: 34.2
0
18
16
14
12
10
8
6
4
2
0
60
40
8
1996
Max: 27.7
10
20
Max: 36.6
1979
15
30
1985
25
20
40
Max: 38.1
30
10
20
5
0
0
0
100
200
300
400
Max: 21.3?
0
100
200
300
# 30 - Redwood Creek, 37o33.3’N, 122o11.4’W, z= 12.8m
Baía de S. Francisco (South Bay) - Clorofila a
8
7
6
5
4
3
2
1
0
45
40
35
30
25
20
15
10
5
0
40
35
30
25
20
15
10
5
0
40
35
30
25
20
15
10
5
0
400
Baía de S. Francisco (South Bay)
Máximo de clorofila a (µg chl a l-1)
120
Anos setenta
100
Tendência crescente
Anos oitenta
80
Anos noventa
60
40
20
Estação 30 - Redwood Creek, 37o33.3’N, 122o11.4’W, z= 12.8m
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
0
Baía de S. Francisco (South Bay)
Máximo de clorofila a (µg chl a l-1)
120
Anos setenta
100
Tendência decrescente
Anos oitenta
80
Anos noventa
60
40
20
Estação 30 - Redwood Creek, 37o33.3’N, 122o11.4’W, z= 12.8m
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
0
Baía de S. Francisco (South Bay)
Máximo de clorofila a em função do número de amostras
120
Clorofila a (µg l-1)
100
Observado
Previsto
80
y=-1.3+1.24x
r=0.6 (P>0.99)
60
40
20
0
0
10
20
30
40
50
Nº de amostras por ano
Estação 30 - Redwood Creek, 37o33.3’N, 122o11.4’W, z= 12.8m
Primary production budget
Tagus estuary (t C y-1)
Pelagic producers
Phytoplankton*1
Benthic producers
41160 (62%)
Sub-total pelagic 41160 (62%)
Total GPP
N removal
Pop. equivalent
Microphytobenthos*2
4265
(6%)
Seaweeds
13770
(21%)
Saltmarsh vegetation*4
7700
(11%)
Sub-total benthic
25735
(38%)
66895 t C y-1
~10500 t N y-1
2.3 X 106 inhabitants
Phytoplankton (62%)
Saltmarsh (11%)
*1
– EcoWin2000 ecological model, Ferreira (2000)
– Modelling and field measurements, Serôdio & Catarino (2000)
*3 – Modelling and field measurements, Alvera-Azcárate et al, (2002)
*4 – Modelling and field measurements, Simas et al. (2001)
*2
Microphytobenthos (6%)
Seaweeds (21%)
Alvera-Azcárate, A., Ferreira, J.G. & Nunes, J.P., 2002. Modelling eutrophication in mesotidal
and macrotidal estuaries - The role of intertidal seaweeds. Est. Coast. Shelf Sci. In Press
Global warming
High nutrient - Low chlorophyll paradox
Pigments
(mg m-3)
0.05
0.10
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
1.80
2.00
5.00
Global climatology of annual mean wind stress
Wind stress
(nt m-2)
0.0
0.1
0.2
0.3
Global seven-year mean pigment fields
Pigments
(mg m-3)
0.05
0.10
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
1.80
2.00
5.00
Phytoplankton from 40m Fe enrichment incubations
Nitschia sp.
2µm
Chavez et al., 1991 - Limnol. & Oceanog. 36, p. 1816-33
PmB (mol O2 mol Chl-1 min-1)
Pm (µmol O2 cell-1 min-1 X 10-10)
Efeito de Fe em curvas P-I para Phaeodactylum tricornutum
40
Cell-specific P vs. I
30
+Fe
20
10
-Fe
0
+Fe
9
6
-Fe
3
Chlorophyll-specific P vs. I
0
0
1000
2000
3000
4000 I (µE m-2 s-1)
Greene et al., 1991. Limnol. & Oceanog. 36, 8, 1772-1782
IronEx I - Large-scale patch experiment in 1993
Mixing Fe and SF6 (artificial tracer) in the equatorial Pacific Ocean.
IronEx I was followed by IronEx II in 1995, which showed conclusively that
phytoplankton production may be limited by Fe.
Dissolved Fe profiles - Antarctic Polar Front
North
North
South
South
Dissolved Fe profiles North (red) and South (blue) of the Polar Front
during JGOFS experiment in the late 1990’s
Phytoplankton growth rates versus
initial Fe concentration
Phytoplankton incubation experiments North and South of Polar
Front during Survey I (blue) and Survey II (red)
Phytoplankton growth rates versus
initial Fe concentration
Phytoplankton incubation experiments North and South of Polar
Front during Survey I (blue) and Survey II (red)
Phytoplankton growth rates versus
initial Fe concentration
Comparison between North and South results
“The pseudo-Michaelis Menten response to added iron in
deckboard enrichment experiments differs north of the APFZ
relative to south of the APFZ, indicating:
•All dissolved iron concentrations are below half
saturation constants, indicating limiting conditions
persist throughout the entire Southern Ocean.
•Waters to the North may be limited by something in
addition to iron (silicate).
•Similar saturation values are consistent with other
observations from other oceans.”
http://color.mlml.calstate.edu/www/news/workshp2.htm
High nutrient - Low chlorophyll
paradox