Cadeias tróficas

Cadeias tróficas e pescas - Tópicos
z Dimensões e requisitos alimentares
z Transferência de energia
z Métodos de pesca
z Capturas
z Avaliação de stocks
Log número de Reynolds (Re)
8
Re = 1.4 X 106 d 1.86
6
4
10 comprimentos s-1
1 comprimento s-1
2
Re = 1.4 X 106 d 1.86
Mamíferos
Peixes
Anfípodes
Zooplâncton
Protozoários
Fitoplâncton
Bactérias
Homem
0
-2
-4
-6
Relação entre o
comprimento
e o número de
Reynolds
-2
-6
-4
1 µm 100 µm 1 cm
0
1m
ud/v = 1.4 X 106 d 1.86
u/v = 1.4 X 106 d 0.86
v = 10-6 m2 s-1
u (ms-1) = 1.4 d 0.86
2
Log comprimento
Comprimento
100 m
Relação entre a ração e o peso individual
em diversas espécies de copépode
Ração diária (% peso a 20oC)
103
102
10
1
10
102
103
Peso seco (µg organismo-1)
Ikeda, T., 1977. J. Exp. Mar. Biol. Ecol., 29, 263-277
Relação entre o comprimento do predador
e presa (> 100 espécies marinhas)
ln comprimento da presa (mm)
6
Protista
Cetacea
4
2
0
Limite de confiança (90%)
-2
-4
-6
y=0.626x - 2.13
-8
-10
-8
-6
-4
-2
0
2
4
r2 = 0.551
6
ln comprimento do predador (mm)
Longhurst, 1991. Limnol. & Oceanog. 36, 8, 1507-1526
8
10
Relação entre a razão predador:presa e o
comprimento do predador
100
Razão presa/predador
Protista
Cetacea
10
1
0.1
0.01
0.001
0.0001
-8
-6
-4
-2
0
2
4
6
ln comprimento do predador (mm)
Longhurst, 1991. Limnol. & Oceanog. 36, 8, 1507-1526
8
10
Distribuição de requisitos
alimentares em Euphasia pacifica
Parâmetro
Peso seco (mg)
Crescimento(Fw/Iw)
Tempo (dias)
% Alimento
Assimilação
Crescimento
Mudas
Ovos
Metabolismo
Laboratório (1)
Laboratório (2)
Campo
1.19
3.95
69
1.65
1.16
63
0.23
39.2
580
86
30
8.0
0
62
78
6.2
7.0
0
86.8
9.4
15.3
8.9
66.4
Lasker, 1966. J. Fish. Res. Bd. Canada, 23, 1291-1317
Produção de diferentes
níveis tróficos no Mar Negro
Nível trófico
Prod. 1arios
Herbivoros
Omnivoros
Carnivoros (1os)
Carnivoros (2-3os)
Alimento
consumido
Taxa de
mortalidade
Diferença
no stock
Produção
(gC m-2 dia-1)
478.5
361.2
67.0
53.5
33.0
12593.8
4.0
1.2
1.3
2.8
5397.2
-6.3
20.0
27.4
-1.1
18469.5
515
170.4
82.2
34.7
Petipa et al., 1970. In Marine Food Chains, Ed. J.H. Steele, 142-167
Produção de peixes em ecossistemas
marinhos
Ecossistema
Produtividade
primária
(gC m-2 ano-1)
Níveis
tróficos
Eficiência
(%)
Produção
de peixes
(mgC m-2 ano-1)
Oceânico
Plataforma
Afloramento
50
100
300
5
3
1.5
10
15
20
0.5
340
36000
Ryther, 1969. Science, 176, 72-76
P = BEn
• P = Productividade do topo da cadeia
• B = Produtividade da base da cadeia
• E = Eficiência ecológica
• n = Número de elos da cadeia trófica
Energyout
E=
Energyin
Predadores
Biomassa 7.0-14.0
Produção 3.5-7.0
Biomassa 1.75-3.5
Produção 0.9-1.8
Bênticos
Biomassa 5.0
Produção 0.5
Peixes batipelágicos
Biomassa 0.02
Produção 0.002
Massa
continental
Biomassa em kcal m-2,
produção em kcal m-2 ano-1
Peixes bênticos
Biomassa 1.0-2.0
Produção 0.1
Zona batipelágica
Peixes mesopelágicos
Zona bêntica
Biomassa 0.5
Produção 0.5-1.3
Zona
Zona
mesopelágica epipelágica
Transferência
de biomassa
em cadeias
tróficas
marinhas
Carnívoros do topo da cadeia
Biomassa 0.03
Produção 0.02-0.03
Physical scales
The three main
ecological variables
plotted on a 3-D grid
Length/time
Organism
Prey
Patch
Stock
Spatial
hierarchy
Predator
Population
Trophic hierarchy
Steele (1988) - Scale selection for biodynamic theories. p.513-526 In B.J. Rothschild (Ed.)
Towards a theory on biological-physical interactions in the world ocean (Kluwer)
Fishing techniques
Pelagic trawl
http://www.sauvonslesdauphins.com/image/chalut.jpg
Fishing techniques
Purse seine
http://www.photolib.noaa.gov/fish/images/fish0704.jpg
Fishing techniques
Purse seine
http://www.europacifictuna.com/purseillustccc.jpg
Fishing techniques
Bycatch – Dolphins in purse seine net
http://www.earthtrust.org/gif/dolphins_in_purse_seine.jpeg
Fishing techniques
Bottom trawl
http://www.trawl.org/trawl.gif
Fishing
techniques
Bottom trawl
http://www.pmel.noaa.gov/
Fishing techniques
Bottom trawl
http://www.dvz.be/images/Photo's/Otter-trawl.jpg
Fishing techniques
Bottom trawl for cod
Aleutian cod trawl
http://www.net-sys.com/act.htm
Fishing techniques
Hard bottom trawl
(for Pollock, Whiting etc)
Hard bottom trawl
http://www.net-sys.com/act.htm
Fishing
techniques
Bottom trawl
http://www.oseanologi.lipi.go.id/trawl.jpg
The State of world fisheries and
aquaculture (SOFIA)- 2000
106 ton y-1
Aquaculture
Fisheries
FAO, 2001. The State of World Fisheries and Aquaculture (SOFIA). Food and Agriculture Organization of the
United Nations. Aquaculture data prior to1984 are estimates.
Distribution of production among major
fish species
4
Alaska pollock
4.5
2.4
2.3
Atlantic herring
Japanese anchovy
2.1
1.3
2
Chilean jack mackerel
4.4
1.9
2.2
Chub mackerel
1.9
1.6
Skipjack tuna
1.7
Anchoveta
Largehead hairtail
1.4
1.3
Atlantic cod
1.2
1.3
Blue whiting
0.6
8.9
1.2
1.2
1.1
Yellowfin tuna
0
2
4
6
8
10
Production (106 ton y-1)
FAO, 2001. The State of World Fisheries and Aquaculture (SOFIA). Food and Agriculture Organization of the
United Nations.
World capture fisheries and aquaculture
WORLD PRODUCTION
INLAND
Capture
Aquaculture
Total inland
MARINE
Capture
Aquaculture
Total marine
Total capture
Total aquaculture
Total world fisheries
UTILIZATION
Human consumption
Reduction to fishmeal and oil
Population (billions)
Per capita food fish supply (kg)
1Preliminary
1994
1995 1996
1997
(million tonnes)
1998
19991
6.7
12.1
18.8
7.2
14.1
21.4
7.4
16.0
23.4
7.5
17.6
25.1
8.0
18.7
26.7
8.2
19.8
28.0
84.7
8.7
93.4
91.4
20.8
112.3
84.3
10.5
94.8
91.6
24.6
116.1
86.0
10.9
96.9
93.5
26.8
120.3
86.1
11.2
97.3
93.6
28.8
122.4
78.3
12.1
90.4
86.3
30.9
117.2
84.1
13.1
97.2
92.3
32.9
125.2
79.8
32.5
5.6
14.3
86.5
29.6
5.7
15.3
90.7
29.6
5.7
15.8
93.9
28.5
5.8
16.1
93.3
23.9
5.9
15.8
92.6
30.4
6.0
15.4
estimate
FAO, 2001. The State of World Fisheries and Aquaculture (SOFIA). Food and Agriculture Organization of the U.N.
European Union fisheries and
aquaculture production
Aquaculture production
Inland production ('000 tonnes)
Percentage of world total
Marine production ('000 tonnes)
Percentage of world total
Fisheries production
Inland production ('000 tonnes)
Percentage of world total
Marine production ('000 tonnes)
Percentage of world total
Fisheries and aquaculture production
Combined total ('000 tonnes)
Percentage of world total
1986
1990
1994
1998
171
3.0
699
20.6
221
2.7
717
14.5
241
2.0
796
9.2
249
1.3
1 085
8.9
113
1.9
6 774
8.6
107
1.7
6 067
7.7
104
1.6
6 737
8.0
120
1.5
6 419
8.2
7 757
8.3
7 114
7.2
7 878
7.0
7 873
6.7
FAO, 2001. The State of World Fisheries and Aquaculture (SOFIA). Food and Agriculture Organization of the
United Nations.
Capture fishery production by country
China
17.2
Japan
5.3
4.7
United States
Russian Federation
Peru
Indonesia
Chile
India
Thailand
Norway
4.5
4.3
3.7
3.3
3.2
2.9
2.9
2
1.8
Republic of Korea
Phillipines
0
5
10
15
20
Capture fishery production (106 ton y-1)
FAO, 2001. The State of World Fisheries and Aquaculture (SOFIA). Food and Agriculture Organization of the
United Nations.
Chinese
fishery data
Watson, R., Pang, L., Pauly, D., 2001.
The Marine Fisheries of China:
Development and Reported Catches.
Fisheries Centre Research Report 9(2).
Univ. British Colombia, Canada.
Avaliação de stocks
z Marcação-recaptura
z Análise de coortes
z Demografia (otolitos e/ou escamas)
z Densidade de ovos
z Curvas stock-recrutamento (MSY)
The triangle of fish migration
Adult stock
(feeding area)
C
Co
nt
ra
na
ta
nt
tm
ui
t
en
De
na
ta
nt
cr
Re
A
Spawning area
Denatant
B
Nursery area
Cushing, D.H., 1975. Marine Ecology and Fisheries, Cambridge Univ. Press
Maximum sustainable yield
Recruitment (106 fish)
3
Region of MSY
2
MSY curve
1
Replacement line
0
0.3
0.6
0.9
Stock (106 fish)
Parsons, Takahashi & Hargrave, 1984. Biological Oceanographic Processes, Pergamon
EcoWin - Conceptual scheme of fish
biomass variation
Growth by food
consumption
Migration by
swimming
Adult
Biomass
Excretion
Recruitment
Spawning
Mortality
(natural or
by fishing)
δB
δt
= Growth + Recruitment - Excretion - Spawning - Death + Swimming
EcoWin - Conceptual scheme of fish life cycle
Growth by yolk sac
absorption
Yolk sac larvae
1 day
Adults
Larvae
1y
Mortality
Excretion
Respiration
s
Mortality
Mortality
Growth by
predation
ay
2d
Growth by
predation
Sp
aw
nin
1d
g
ay
Eggs
ear
Growth by
predation
Juveniles
Mortality
Excretion
Respiration
1
nth
o
m
Mortality
Excretion
Respiration
Time and space scales for different groups
Greenhouse
effect
10,000
sh
Fi
Time (days)
1000
o
kt
n
a
pl
o
Zo
100
n
to
k
lan
p
o
yt
h
P
10
n
Storms
1
1
10
100
1000
10,000
Space (km)