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Attaining Operational Marine Biodiversity ObservationsAttaining Operational Marine Biodiversity Observations2424--27 May 2010, Washington, DC27 May 2010, Washington, DC
Overview of Overview of Pelagic HabitatsPelagic Habitats
Pelagic HabitatsPelagic Habitats
•• Extreme size, challenging to accessExtreme size, challenging to access•• Wide range of relevant space / time scalesWide range of relevant space / time scales•• Extraordinary phylogenetic diversityExtraordinary phylogenetic diversity
Synergistic application of varied observing Synergistic application of varied observing approaches essentialapproaches essential
How can we best achieve this?How can we best achieve this?
• The pelagic: 1.3 million km3 (99% of living space on planet)– Euphotic zone – relatively small volume but where bulk of production takes place
– “Dark” ocean ‐ largest habitat in biosphere
• Know most about coastal, shallow water, small to medium sized organisms. – know least about blue‐water, very small or large, fast moving species.
– most information still comes from nets or filtering organisms through sieves.
– neither can effectively collect very small or fragile organisms
Census of Marine Life
epipelagic100 m
Arístegui et al. 2009Stedmon 2004
PelagicDepth Ranges
Reflect extreme environmental gradients
Associated changes in planktonic community structure
Many scales of spatial and temporal variability
Dissolved oxygen
Surface
750 m
3000 m
Wide variation in pelagic
Reflecting balance of photosynthesis respiration atmospheric exchangecirculation and mixing
Gradients in TemperaturePressure NutrientsLightpH….
Annual surface PO4
Many scales of spatial and temporal variability
Color scale blue-red = 0 - 2 µM
Global scale variation in photosynthetic biomass
SeaWiFS Biosphere
Smaller scale variability in pelagic habitat
MODIS Aqua
Continental shelves, banks, semi-enclosed basins
Boundary current rings & meanders
MODIS Aqua (Gulf Stream)
Watersheds & Estuaries
Chesapeake Bayhttp://oceancolor.gsfc.nasa.gov/
SST Chl
Scales important for biodiversity regulation?
Pelagic biodiversity encompasses universal tree of life
http://hermes.mbl.edu/labs/Sogin/Pages/univ.html
Size range ~8 orders of magnitude
Abundance range> 10 orders of magnitude
Phylogenetic diversity of photoautotrophs in aquatic systems higher than terrestrial. Bulk of diversity in the pelagic.
Falkowski et al. 2004
Big challenge, but also
Opportunity to learn about fundamentals of life on Earth
Diversity not homogenously distributed over time or space
Temporal variationSeasonal variations in bacterial biodiversity
Discriminant function and time series analyses
annual, repeatable cycles in bacterial biodiversity
Fuhrman et al, 2006
California coastal surface watersBacterial diversity over 5 years
San Pedro Ocean Time Series (SPOTS)
Potential for bias or aliasing with less observational resolution
Worm et al 2003
Spatial variation in top predator diversity in NW Atlantic tunas, sharks, billfishes, turtles, mammals, etc.
From longline logbooks~ 10 years
Diversity not homogenously distributed over time or space
Hotspots of diversityshelf breaksseamountsreefs…
Color codes indicate # species
per 50 individuals
Is more biodiversity better?Changes in biodiversity with climate change
First occurrence in late 1990s(diatom Neodenticula seminae)
Event‐scale shiftIncoming pulse of N. Pacific water
First N. Atlantic record in >800,000 yrs
Can be abundant component of plankton
More trans‐Arctic migrations expectedWill change biodiversity
May influence biological pump and carbon cycling
Reid et al. 2007
Occurrence of Pacific Diatom species in NW Atlantic
~50 year Continuous Plankton Recorder (CPR) dataset
More diversity? Continued…
Changes in N. Atlantic copepod assemblages, 1958‐2005Shift northward in warm‐temperate
and temperate sp.
Reduced number of cold‐temperate and subarctic species
Changes correlate with sea surface temperate changes
Rate of biogeographic changes far exceeds what is observed in terrestrial environmentsCopepods may better reflect
current impact of climate change on ecosystems
Is the pelagic particularly sensitive to climate change?
Beaugrand et al, 2009~50 year Continuous Plankton Recorder (CPR) dataset
PDO and its open ocean impacts influence nearshore ecosystem shifts
> 50 years of fishery landings data
Chavez et al. 2003
Status and Trends Examples Status and Trends Examples
Increased prevalence and extent of Harmful Algal Blooms in US waters
http://www.whoi.edu/redtide/Cell images from Imaging FlowCytobot
(Sosik and Olson)
Species level identity essential
Local-regional habit scalese.g., inner shelf, bays, estuaries
Pelagic HabitatsPelagic Habitats
•• Extreme size, challenging to accessExtreme size, challenging to access•• Wide range of relevant space / time scalesWide range of relevant space / time scales•• Extraordinary phylogenetic diversityExtraordinary phylogenetic diversity
Synergistic application of varied observing Synergistic application of varied observing approaches essentialapproaches essential
How can we best achieve this?How can we best achieve this?
Breakout Group QuestionsBreakout Group QuestionsWhat major habitat divisions should guide effort?What major habitat divisions should guide effort?
What level of habitat resolution is needed to answer our What level of habitat resolution is needed to answer our questions?questions?
What taxa should be observed?What taxa should be observed?
What taxa, spatial and temporal scales are missing What taxa, spatial and temporal scales are missing but required, e.g., for modeling C budgets / but required, e.g., for modeling C budgets / dynamics, documenting global change?dynamics, documenting global change?
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