Transcript Physical-biological Coupling in Marine Ecosystems

OEAS 604: Final Exam
• Tuesday, 8 December
• 8:30 – 11:30 pm
• Room 3200, Research Innovation
Building I
• Exam is cumulative
• Questions similar to quizzes with
focus on concepts
Physical-biological Interactions
OEAS 604
Lecture Outline
1) Recruitment to marine fisheries
2) Modeling physical-biological
interactions
3) Global environmental change
programs
Recruitment patterns
Why patterns occur and what are key processes?
Changes in Abundance of Key
Species
Calanus finmarchicus
months
(Beaugrand)
12
11
10
9
8
7
6
5
4
3
2
1
60 65 70 75 80 85 90 95
Years (1958-1999)
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
Calanus helgolandicus
12
11
10
9
8
7
6
5
4
3
2
1
60 65 70 75 80 85 90 95
Years (1958-1999)
Copepod abundance in North Sea
Consequences for fish production
and recruitment
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
Challenge
• Recruitment to marine fish populations
depends on:
• Variations in larval feeding and nutrition –
Lasker (1981)
> larval feeding provides direct link from zooplankton to
the consumer
• Advection into favorable/unfavorable
environmental conditions – Hjort (1914)
> requires knowledge of the scales that are relevant to the
planktonic organism
Combining two requires understanding of dependence
of population dynamics on the physical structure of the
ocean and links to ecosystem dynamics
Scales of Processes
• View that marine ecosystems operate along a
continuum defined by space and time
• Now - View has evolved to one in which marine
ecosystem variability and population recruitment
result from the integration of processes across all
scales and includes direct as well as indirect
interactions
Processes at all scales
influence variability of
marine organisms and
populations
Studies of marine
ecosystems require
integration of the
environmental drivers
and biological responses
Knowledge of scale interactions have resulted in
additional hypotheses about physical-biological
controls on recruitment
Development of conceptual frameworks for
recruitment that encompass multiple scales
Field and Modeling Programs to Test Conceptual Models
Predators
Cod larvae
and early juveniles
Copepods
Russia
OCEAN CLIMATE
PARAMETERS
Transport
Temperature
Light conditions
Turbulence
Phytoplankton
Trophic transfer and
habitat conditions
Modeling Physical-Biological
Interactions
• Modeling has been central to advancing
understanding of physical-biological interactions
• Built on scientific and technological advances,
such as realistic circulation models
• Integration of concentration-based models and
IBMs with circulation models resulted in ability to
project future states of ecosystems and to
understand processes
• Allowed identification of spawning areas,
recruitment regions, connectivity of populations
at a range of scales
Riley (1946, JMR)
No predictive
power or
indication of
controlling
processes
Understand the processes controlling the
spring bloom
Used a regression model that included
environmental variables – temperature
Developed a mechanistic mathematical model
dP = P(Ph – R – G)
dt
Time change P = photosynthesis – respiration – grazing
Included processes that affect the concentration and
abundance of phytoplankton
Physical-biological models
evolved to systems of
interconnected modules
NEMURO - minimum trophic
structure and biological
relationships … thought to
be essential in describing
ecosystem dynamics in the
North Pacific
Coastal Gulf
of Alaska
Realistic Regional
Circulation Models
Include sea ice, coupling
to atmospheric models
and larger scale models
West Antarctic
Peninsula
Population connectivity at regional to circumpolar scales
Thorpe et al. (2007)
Importance
of
comparative
studies
Connection between spawning and
recruitment regions
Inclusion of detailed biology
provides process understanding
Future
Models evolving
to include humans
as part of the
marine food web
Perry et al. (in press)
Importance of top predators
including humans
Barange et al. (in press)
Population
Age
Structured
Model
variability
Fishing
catch
Temperature, Currents,
Plankton Biomass, Oxygen
New
Production
CLIOTOP
Tuna Forage Model
Global Environmental Change
Programs
• Integrated Marine Biogeochemistry and
Ecosystem Research (IMBER) Program
• Surface Ocean-Lower Atmosphere (SOLAS)
• Land-Ocean Interactions in the Coastal Zone
(LOICZ)
• Past Global Changes (PAGES)
• International research programs sponsored
by the International Geosphere-Biosphere
Programme (IGBP) and the Scientific
Committee on Oceanic Research (SCOR)
IMBER
FOUR RESEARCH
THEMES
 Interactions between
biogeochemical cycles
and marine food webs
 Sensitivity to global
change
 Feedbacks to the Earth
System
 Responses of society
SOLAS
• understand the key biogeochemicalphysical interactions and feedbacks
between the ocean and atmosphere
• Exchange processes at the air-sea
interface and the role of transport and
transformation in the atmospheric and
oceanic boundary layers
• Air-sea flux of CO2 and other long-lived
radiatively active gases
LOICZ
• support sustainability and adaptation to
global change in the coastal zone
• include developing and testing
integrated multidisciplinary
(natural+economic+social) methods to
analyze the environmental and social
interactions and feedbacks governing
coastal system status and changes
PAGES
• improve our understanding of past
changes in the Earth System in order to
improve projections of future climate
and environment, and inform strategies
for sustainability
Future Earth
COP21
Next Class
• Instruments and models
• Chapter 6, Talley et al.