Ew E NEST m odel Thorsten Blenckner Maciej T. Tomczak Susa - - PDF document

▶
ew e nest m odel
SMART_READER_LITE
LIVE PREVIEW

Ew E NEST m odel Thorsten Blenckner Maciej T. Tomczak Susa - - PDF document

Nov 22, 2023 305 likes •513 views

Ew E NEST m odel Thorsten Blenckner Maciej T. Tomczak Susa Niiranen Olle Hjerne Baltic Nest Institute (BNI) Linking science and management Baltic NEST = a science based decision support system (DSS) to : Explore and synthesize

slide-1
SLIDE 1

Ew E NEST m odel

Maciej T. Tomczak Thorsten Blenckner Susa Niiranen Olle Hjerne

slide-2
SLIDE 2

2 DTU Aqua, Technical University of Denm ark

Baltic Nest Institute (BNI) – Linking science and management

Baltic NEST = a science‐based decision support system (DSS) to :

  • Explore and synthesize ecosystem

information

  • Evaluate the effects of

eutrophication and fishery

  • Calculate costs of different

management options Baltic NEST can be used with any computer with internet access and can be downloaded free from nest.su.se/nest.

slide-3
SLIDE 3

3 DTU Aqua, Technical University of Denm ark

Drainage basin modeling Marine modeling Marine and runoff data Atmospheric emissions and load Fishery management Cost minimization model

NEST DSS builds on six different models

slide-4
SLIDE 4

4 DTU Aqua, Technical University of Denm ark

Nest food web model

  • A Baltic Proper food web model incorporating groups from

phytoplankton to fishery (based on Harvey et al.,2003)

  • Aim to create a model that is able to:
  • Reproduce historical (1974 ‐>) phenomena (e.g. regime

shifts) and help to identify past food web dynamics

  • Incorporate fishery impact
  • Quantify responses to environmental variation and indicate

potential changes in food‐web interactions to future climate change (2007‐2100) linkage to biogeochemical models

  • Currently the model is parameterized to fit fish biomasses to

XSA‐data (1974‐2007)

slide-5
SLIDE 5

5 DTU Aqua, Technical University of Denm ark

Modelling approach

  • An Ecopath with Ecosim‐approach (www.ecopath.org)

employed, where: ‐ Ecopath (mass‐balance)

P = Mp+ F + Mother + BA + migration C = P + Unass. food + R

‐ Ecosim (simulation)

  • 28 functional groups

(23 living, 3 fleets, 2 detritus)

  • Multi‐stanza groups for 3 main species
slide-6
SLIDE 6

6 DTU Aqua, Technical University of Denm ark

Spring phytoplankton Bacteria Microzoopl. Mysids Meiobenthos Seals Detritus sed

Age 0 Age 0 Age 0

Eggs/larvae

Pseudocalanus Acartia Temora Other... Macrozoobenthos Cyanob. Other...

Age 1

Herring

Age 2 etc.. Age 2, etc Age 1

Cod

Age 2, etc... Age 1

Sprat DOM

Spr_fleet Cod_fleet Her_fleet

slide-7
SLIDE 7

7 DTU Aqua, Technical University of Denm ark

Spring phytoplankton Bacteria Microzoopl. Mysids Meiobenthos Seals Detritus sed

Age 0 Age 0 Age 0

Eggs/larvae

Pseudocalanus Acartia Temora Other... Macrozoobenthos Cyanob. Other...

Age 1

Herring

Age 2 etc.. Age 2, etc Age 1

Cod

Age 2, etc... Age 1

Sprat DOM

Spr_fleet Cod_fleet Her_fleet

RV Temp

N, P O2

?

slide-8
SLIDE 8

8 DTU Aqua, Technical University of Denm ark

Forcing Factor Seson Forced Group Type of forcing 1 Tem p_ 0 _ 1 0 _ Aug Sum m er Sprat eggs production 2 Tem p 0 _ 5 0 m _ spring Spring Acartia sp; Them ora sp im pact on biom ass 3 CodRV Annual Cod eggs production or youngest stanza 4 macrozoobenthos Annual macrozoobenthos 5 Acartia Annual Acartia sp 6 Temora Annual Temora sp 7 Pseudocalanus Annual Pseudocalanus sp 8 PP Spring spring phytoplankton 9 PP Summer

  • ther phytoplankton

10

  • cyanobacteria

11 B_Sprat 1 Annual Sprat Age 1 12 B_Ad. Sprat Annual Sprat Age 2+ 13 B_Herring 1 Annual Herring Age 1 14 B_Herring 2 Annual Herring Age 2 15 B_Ad. Herring Annual Herring Age 3+ 16 B_Cod 2 Annual Cod Age 2 17 B_Cod3 Annual Cod Age 3 18 B_Ad. Cod Annual Cod Age 3+ to fit relative biom ass tim e series from XSA 19 F_ Sprat 1 Annual Sprat Age 1 20 F_ Ad. Sprat Annual Sprat Age 2 + 21 F_ Herring 1 Annual Herring Age 1 22 F_ herring 2 Annual Herring Age 2 23 F_ Ad. Herring Annual Herring Age 3 + 24 F_ Cod 2 Annual Cod Age 2 25 F_ Cod3 Annual Cod Age 3 26 F_ Ad. Cod Annual Cod Age 3 + Fishing pressure on given group XSA

slide-9
SLIDE 9

9 DTU Aqua, Technical University of Denm ark

slide-10
SLIDE 10

10 DTU Aqua, Technical University of Denm ark

2 4 6 8 10 12 14 16 18 20 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2)

SPRAT

2 4 6 8 10 12 14 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 0.5 1 1.5 2 2.5 3 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 0.5 1 1.5 2 2.5 3 3.5 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 2 4 6 8 10 12 14 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 0.2 0.4 0.6 0.8 1 1.2 1.4 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2)

HERRING COD

slide-11
SLIDE 11

11 DTU Aqua, Technical University of Denm ark

2 4 6 8 10 12 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 1 2 3 4 5 6 7 8 9 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 10 1 2 3 4 5 6 7 8 1974 1979 1984 1989 1994 1999 2004 2009 Year Biomass (t/km2) 9

1 2 3 4 5 6 7 1974 1979 1984 1989 1994 1999 2004

1 2 3 4 5 6 1974 1979 1984 1989 1994 1999 2004

Shift in zooplankton community

slide-12
SLIDE 12

12 DTU Aqua, Technical University of Denm ark

Catch vs. TL… fishing dow n to the food w eb??

1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 19941995 1996 1997 1998 1999 2000 2001 2002 2003

3.55 3.6 3.65 3.7 3.75 3.8 3.85 3.9 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 Log (Total Catches) Mean TL Catch

2004 200 200 200 2006 2007

slide-13
SLIDE 13

13 DTU Aqua, Technical University of Denm ark 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1974 1984 1994 2004 2014 2024 2034 2044 2054 2064 2074 2084 2094 Years Biomass (t x km-2)

F= 0.9

Simulation secanrio

Fisheries and Climat Change on Cod biomass

Scenarios Fishing Climate BAU=means no CC

slide-14
SLIDE 14

14 DTU Aqua, Technical University of Denm ark 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1974 1984 1994 2004 2014 2024 2034 2044 2054 2064 2074 2084 2094 Years Biomass (t x km-2)

F= 0.9

Simulation secanrio

Fisheries and Climat Change on Cod biomass

Scenarios Fishing Climate BAU=means no CC BAU=means CC

slide-15
SLIDE 15

15 DTU Aqua, Technical University of Denm ark 0.5 1 1.5 2 2.5 1974 1984 1994 2004 2014 2024 2034 2044 2054 2064 2074 2084 2094 Years Biomass (t x km-2)

F= 0.9 F= 0.3

Simulation secanrio

Fisheries and Climat Change on Cod biomass

Scenarios Fishing Climate

BAU=means no CC BAU=means CC F=0.3 no CC F=0.3 CC

slide-16
SLIDE 16

16 DTU Aqua, Technical University of Denm ark 0.5 1 1.5 2 2.5 3 3.5 4 1974 1984 1994 2004 2014 2024 2034 2044 2054 2064 2074 2084 2094 Years Biomass (t x km-2)

F= 0.9 F= 0.3 F= 0

Simulation secanrio

Fisheries and Climat Change on Cod biomass

Scenarios Fishing Climate

BAU=means no CC BAU=means CC F=0.3 no CC F=0.3 CC F=0 no CC F=0 CC

slide-17
SLIDE 17

17 DTU Aqua, Technical University of Denm ark

Scenario test - Conclusions

  • Strong effect of fisheries management actions on cod stock recovery
  • Model predict a no return of cod SSB to the medium level observed in

1990’s if the fishing continues at current level

  • ”Business As Usual” scenario will hinder a recovery of the Eastern Baltic

cod stock

  • Reduction in fishing pressure has a smaller positive effect on the cod

stock in a future changing climate then if climate change is not occur

  • Climate change scenarios gave minor effect on cod stock recovery, but

large effects on the food web, however more scenarios have to be test

  • More scenarios can be found in ICES/ HELCOM Working Group on

Integrated Assessment of the Baltic Sea Report 2009

slide-18
SLIDE 18

18 DTU Aqua, Technical University of Denm ark

Overall sum m ary ( pros)

  • Address and answer ecological questions and hypothesis:

– Reproduce past dynamic of whole food-web at all trophic levels – Quantifies the ”regime-shift” in the Baltic sea ecosystem – Quantifies top-down vs. bottom-up control

  • Evaluate effect of environmental changes

– Simulate the ecosystem response to climate change and changes in primary productivity

  • Evaluate ecosystem effect of fishing

–

  • n fish stocks

–

  • n whole ecosystem structure (fish down to the food web)

– estimate fisheries related trophodynamic indicators (e.g TL)

slide-19
SLIDE 19

19 DTU Aqua, Technical University of Denm ark

Overall sum m ary ( cons)

  • Only main commercial fish groups are included

– lack other important components (salmons, flat fishes) – lack of interaction with coastal zones

  • Annual model step (no seasonality)
  • Only 3 fishing fleets related to fish species
slide-20
SLIDE 20

20 DTU Aqua, Technical University of Denm ark

Overall sum m ary ( to do...)

  • True coupling between Nest food web model and a biogeochemical

model (BALTSEM) applied in the NEST to test effect of HELCOM Baltic Sea Action Plan on entire food-web including fisheries Explore management policy options to produce policy-relevant information on combined future (present-2100) impacts of CC and industrial + agricultural practices on Baltic Sea ecosystem

  • Evaluate impact and placement of marine protected areas
  • Link other NEST components to food-web model

Uncertainty

  • Depend on data quality and quantity (monitoring data

extremely important !)

  • Unknown food-web interactions
  • Comparable with other Baltic model