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Marine Biodiversity, Climate Change and Human Impacts Contributors: C Smith, K. Weng, R. Waller, G. Steward, J. Drazen, G.Wang, others in spirit Why care about marine biodiversity and climate change? - Ocean ecosystems contain remarkable, but still very poorly
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Marine Biodiversity, Climate Change and Human Impacts • Contributors: C Smith, K. Weng, R. Waller, G. Steward, J. Drazen, G.Wang, others in spirit • Why care about marine biodiversity and climate change? • - Ocean ecosystems contain remarkable, but still very poorly • known, levels of biodiversity & evolutionary novelty • Ecosystem functions (& services) are modulated by biodiversity • Humans are altering marine biodiversity at an accelerating • rate on a global scale Abyssal sea cucumber
A major focus in Biological Oceanography is now: • Evaluating patterns and drivers of marine biodiversity: • - microbes to whales • - populations to ecosystems • - local to global scales • - intertidal to the abyss • 2) Predicting the response of biodiversity and ecosystem • function to human threats, e.g.: • - climate warming • - ocean acidification • - resource exploitation (fishing, mining, etc.) • BOD has major efforts and opportunities in the study of marine biodiversity and climate change – • - Here are a few highlights to provide a flavor of these activities • spanning tropics to polar regions Bacterioplankton Whale-fall community
- Field program of Census of Marine Life - PI’s Craig R. Smith and Pedro Martinez (Germ.) - Funded by A. P. Sloan Foundation ($2.6 million for 2004 – 2010) and $500,000 co-funding (Pew, etc.) Evaluating patterns & causes of biodiversity in the global abyss Why care about the abyssal seafloor (3000 – 6000 m)? - >50% of Earth’ surface (the “Big Blue”) - Biodiversity and ecosystem function poorly evaluated - May be Earth’s largest reservoir of biodiversity - Hawaii sits in middle of it
Key CeDAMar questions include: • Is the abyss a major reservoir of biodiversity? • How will abyssal biodiversity and ecosystem function respond to climate warming? Coordinated Field Efforts Include: • Latitudinal gradients (DIVA, BIOZAIRE) • Antarctic Diversity and Biogeography (ANDEEP) • Biodiveristy and species ranges in Pacific (KAPLAN, NODINAUT) • Diversity in a warm abyss (LEVAR) • Diversity versus primary production (CROZEX) • Decadal changes in abyssal fauna: (PAP) PAP Beyond 2010 - focus on still unstudied regions – e.g., South Pacific
Another aspect of biodiversity studies - delineating the large marine ecosystems of the open oceanUsing The Original OceanographersKevin Weng Pelagic fishes ply the oceans with advanced sensor packages (movement, image recognition, light, sound, real-time chemical recognition etc.). They help us to discover and understand important bioregions of the ocean. Thresher sharks Lamnid sharks Tunas Billfishes
Pelagic Fishes can be Tracked with Recently Developed Tools SPOT fin-mounted transmitter - Argos position Juvenile white shark Adult white shark Salmon shark PAT Tag - Temperature, Pressure, Light
Salmon Shark Seasonal Distribution:White Sharks (n = 15) Identify regions of productivity White shark Region of low productivity: mysterious biological function Weng et al. Accepted
Antarctic Marine Ecosystems are fundamentally structured by sea ice and ice shelves HOWEVER! Antarctic Peninsula region is undergoing extremely rapid warming (2.5oC since 1940) and ice loss Ice Shelf Sea Ice Two NSF funded projects studying climate warming on Antarctic Ecosystem function
GLOBAL CLIMATE CHANGE AND BENTHO-PELAGIC COUPLING ON THE ANTARCTIC PENINSULA - NSF 2007-2010 • C. Smith, R. Waller, UH students and postoc • UH Collaborators – Steward, Wang, Rappe • Co-PIs DeMaster & Thomas – NCSU • GOALS: • 1) Evaluate seafloor • ecosystem change along sea-ice gradient from 63o - 68o S • 2) Predict response of Antarctic ecosystemS to loss of sea ice from global warming A Ice free most of year (8 mo) B C D E Cruises: Feb 08, July 08, Feb 09 Ice bound most of year (8 mo)
Abrupt Environmental Change in the Larsen Ice Shelf Ecsystem C. Smith, UH postdoc , student Maria Vernet (SIO) , Cindy Van Dover (Duke) , Mike McCormick (Hamilton College) NSF – IPY Project (2007 -2011) Multi-disciplinary field program Larsen B collapse – Area the size of Rhode Island disintegrated in 5 wk in 2002 • Goals: • Evaluate ecosystem response (sea surface to seafloor) of ice-shelf loss • Predict the consequences of ice-shelf collapse in other regions • Major cruises: 2010 (62 d), 2011
Deep-sea corals: ecology, genetics, larval biology, and anthropogenic impactsRhian Waller & collaborators • Biodiversity • Who is where and why? - Not known in most areas • Population Connectivity • modern techniques to link present populations • Reproductive ecology and larval dispersal • ancient DNA techniques to link past populations to present • Responses to climate change – acidification and warming • Using ancient and modern DNA techniques to investigate seamount population flux in the past 30,000 years - making models for climate future • Acidification/temp. experiments on deep-water corals/larvae skeletogenesis • Anthropogenic Impacts • Fisheries Impacts • Oil Rig Impacts • Precious Coral Harvest • Using Reproductive/Genetic techniques to examine both
Major opportunity in biodiversity and climate change research – Climate change impacts on coral reef ecosystems - - field studies - modeling - interdisciplinary integration Midway Island Pearl & Hermes Atoll Papahānaumokuākea Marine National Monument – largest most pristine reefs in USA
Abyssal benthos = indicator of strength of “Biological Pump” CO2 Statistical Funnel of export flux 200-500 km diameter (>30,000 km2) CO2 Carbon Sequestration Abyss Benthic Community Structure and Function National Oceanography Center Structure & function of abyssal communities strongly shaped by the Biological Pump indicators of the export of carbon from large areas of surface ocean, through water column, to seafloor
One broad finding – abyssal ecosystem structure/function tightly coupled to export producion Increased SST and reduced upwelling resulting from global warming Large reductions in export flux and dramatic changes in abyssal ecosystems Smith et al in review in Trends in Ecology and Evolution
Figure 4.19. Rates of surface elevation change (dS/dt) derived from ERS radar-altimeter measurements between 1992 and 2003 over the Antarctic Ice Sheet (Davis et al., 2005). Locations of ice shelves estimated to be thickening or thinning by more than 30 cm yr–1 (Zwally et al., 2006) are shown by red triangles (thickening) and purple triangles (thinning).