globec gb-4b pi meeting (6/23/2008)
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GLOBEC GB-4B PI Meeting (6/23/2008). - PowerPoint PPT PresentationTRANSCRIPT
Processes controlling copepod distribution in Processes controlling copepod distribution in the Gulf of Maine - Georges Bank regionthe Gulf of Maine - Georges Bank region
R. Ji & C. DavisR. Ji & C. DavisDepartment of BiologyDepartment of BiologyWoods Hole Oceanographic InstitutionWoods Hole Oceanographic Institution
Working with:Working with: PI team:PI team: Chen, Beardsley, Townsend, Runge, Durbin, FlaggChen, Beardsley, Townsend, Runge, Durbin, FlaggUMASS-D modeling group:UMASS-D modeling group: Q. Xu, G. Cowles, R. Tian, S. Hu, D. StuebeQ. Xu, G. Cowles, R. Tian, S. Hu, D. StuebeDavis Lab:Davis Lab: Q. Hu, C. PetrikQ. Hu, C. Petrik NMFS:NMFS: D. Mountain, J. Hare, M. TaylorD. Mountain, J. Hare, M. Taylor
GLOBEC GB-4B PI Meeting (6/23/2008)GLOBEC GB-4B PI Meeting (6/23/2008)
Pm, Os
Cf, Pn Cf, Pn
Cham, Ctyp, Tl
Ctyp
Cfin: Calanus finmarchicusPcal: Pseudocalansu spp.Pm: Pseudocalanus moultoniPn: Pseudocalanus newmaniOs: Oithona spp.Cham: Centropages hamatusCtyp: Centropages typicusTl: Temora longicornis
Yellow: abundant in summer/fallWhite: abundant in winter/spring
Food-limit Resting egg
CfinPcal
Os
ChamCtypTl
x
x
xx x
x
Egg carrier
x
x
(Based on Davis 1984, 1987; Durbin&Casas, 2006)
- Peak in different season- Different external sources- Difference in life history traits
Dominant Dominant copepodscopepods Ctyp
PcalPcal
Jan-Feb Mar-Apr
May-Jun
Sep-Oct
Jul-Aug
Nov-Dec
PcalPcal ““Cold-water” species, peak in spring and early summerCold-water” species, peak in spring and early summer Higher development rate in lower temperatureHigher development rate in lower temperature Lower EPR compare to Ctyp, Cfin, similar to ChamLower EPR compare to Ctyp, Cfin, similar to Cham Lower egg mortality (egg carrier)Lower egg mortality (egg carrier) High concentration in shallow area (food limitation?)High concentration in shallow area (food limitation?) Maintain population size on the Bank, supply from Maintain population size on the Bank, supply from
upstream (match Davis 1984)upstream (match Davis 1984) Decrease of abundance after summer: Decrease of abundance after summer:
1.1. high mortality rate in the model (T-dependent, high mortality rate in the model (T-dependent, increase of predator in summer, Q10, visual increase of predator in summer, Q10, visual predator)predator)
2.2. other possible reason: less food (tested, false), less other possible reason: less food (tested, false), less EPR in warmer water (no exp support)EPR in warmer water (no exp support)
CtypCtyp
Jan-Feb Mar-Apr
May-Jun
Sep-Oct
Jul-Aug
Nov-Dec
CtypCtyp
““Warm-water” species, peak in later summer and fallWarm-water” species, peak in later summer and fall Lower development rate in cold temperatureLower development rate in cold temperature higher EPR compare to Pcal and Chamhigher EPR compare to Pcal and Cham Higher egg mortality (“broadcaster”)Higher egg mortality (“broadcaster”) Higher concentration in shallow area, but not confined Higher concentration in shallow area, but not confined
in shallow area (food limitation less obvious, in shallow area (food limitation less obvious, dispersive?)dispersive?)
Increase of abundance after summer (EPR increase)Increase of abundance after summer (EPR increase)
ChamCham
Jan-Feb Mar-Apr
May-Jun
Sep-Oct
Jul-Aug
Nov-Dec
ChamCham
““Warm-water?” species, peak in mid-summer, Warm-water?” species, peak in mid-summer, relatively high population in fall than winter/springrelatively high population in fall than winter/spring
Lower development rate in cold temperatureLower development rate in cold temperature Lower EPR compare to Cfin and Ctype, similar to PcalLower EPR compare to Cfin and Ctype, similar to Pcal High egg mortality (“broadcaster”)High egg mortality (“broadcaster”) High concentration in shallow area only (especially High concentration in shallow area only (especially
GB): Resting egg strategy + food limitationGB): Resting egg strategy + food limitation
Working hypothesisWorking hypothesis(from proposal)(from proposal)
“… The same model structure will be used for all species, changing only the parameter values (temperature/food/life-stage dependent egg production rate, development rate, growth rate, and normalized stage-dependent mortality) and behaviors, and thus expediting the model runs. The inputs of The inputs of characteristic life history traits of each species characteristic life history traits of each species together with its initial abundance patterns should together with its initial abundance patterns should generate its observed characteristic seasonal/spatial generate its observed characteristic seasonal/spatial patternspatterns…”…”
Model FrameworkModel Framework
Fully 3-D coupling
FVCOM-based(fvcom.smast.umassd.edu)
Food web model - NPZD (Ji et al., in press)
Mean-age zoop model(Hu et al., 2007)
Zooplankton model
Egg
Nauplii
Copepodite
Zooplankton
PhytoplanktonNitrogen
Food web model
Adult
Physical models
Atmospheric Model MM5/WRF
Ocean Model (FVCOM)
Ocean GCM
Global Tidal Model
FreshwaterInput
Satellite SST, U,V
BuoysT,S,U,VAltimeter
Detritus
Major features
A Generic Copepod ModelA Generic Copepod Model*Dimensionless, change parameters only
Belehradek function (egg)Belehradek function (egg)
Belehradek function (Nauplii)Belehradek function (Nauplii)
Belehradek function (Copepodite)Belehradek function (Copepodite)
EPR (T dependent)EPR (T dependent)
cfin
EPR (Food dependent)EPR (Food dependent)
Pcal (vavg) Pcal (vavg)
GB Crest
Jordan Basin
Exp. 1Exp. 1
Change D=f(T) to Cham/Ctyp
Population can’t be maintained
To maintain population:1. increase EPR (Ctyp) 2. Resting egg (Cham)
GB Crest
Jordan Basin
Exp. 2Exp. 2
Follow Exp. 1, but increase EPR
Population peak in summer/fall
Population size explodedpossible reason: egg mortality“broadcaster” vs “carrier”
GB Crest
Jordan Basin
Exp. 3Exp. 3
Follow Exp. 2, but increase egg mortality (from 3% to 15%)
Population peak in summer, not in fall, similar to Pcal in Exp. 1 (mortality issue?, see Exp. 4)
GB Crest
Jordan Basin
Exp. 4Exp. 4
Follow Exp. 3, decrease Q10m
Population peak in summer/fall
GB Crest
Jordan Basin
Mortality T-dependent might be different between Ctyp and Pcal.Any biological reason?
Exp. 5: Pcal GoM contributionExp. 5: Pcal GoM contribution
Increase initial concentration of Pcal in GoM by 10x
Examine the contribution of GoM population from last year
Ex. 6: Self-sustainability on GBEx. 6: Self-sustainability on GB
No GB initial population
Initialize GB only
Ex. 7: Effect of upstream inputEx. 7: Effect of upstream input
Yr 1
Yr 2
Yr 3
A: Baseline runB: No upstream input from Nova Scotia
Resting egg strategy (no mortality)
Resting egg strategy (with mortality)
SummarySummary
Different life history traits + environmental condition Different life history traits + environmental condition determine the spatiotemporal distributional patterns of determine the spatiotemporal distributional patterns of dominant copepod speciesdominant copepod species
Different reproduction strategies are used to maintain Different reproduction strategies are used to maintain population in GoM or on GB, including r-strategy (e.g. population in GoM or on GB, including r-strategy (e.g. “broadcaster” for Ctyp) and prolonged life history (e.g. “broadcaster” for Ctyp) and prolonged life history (e.g. resting egg for Cham). resting egg for Cham).
Pcal population is difficult to maintain in GoM/GB Pcal population is difficult to maintain in GoM/GB without upstream input, posibily due to k-strategy (“egg without upstream input, posibily due to k-strategy (“egg carrier”, less dispersive)carrier”, less dispersive)
Mortality control the population size, a sensitive Mortality control the population size, a sensitive parameter but difficult to estimateparameter but difficult to estimate