SIBER SPIS sept 2011.pdf - IMBER

SIBER
Science Plan and Implementation Strategy
column. In addition to large-scale spatial measurements (transects), time series measurements
of nutrients, hydrographic, and CO 2 system properties provide important information needed
for modeling future impacts. There is a particularly pressing need for additional measurements
in the southern IO and the IO sector of the Southern Ocean. The 30-year observational record
from the southwestern IO discussed above provides a cornerstone for quantifying temperature
and CO 2 increases in the southern IO and it is expected that their continuation will provide
crucial information on the carbon cycle and climate impacts in this under-sampled region.
Human Activities:
2) How are present day increases in human populations and coastal development
influencing biogeochemical cycles and ecosystem dynamics in the coastal zone of the
IO and how will these impacts be manifested in the future
How, in general, is coastal development affecting marine ecosystems around the IO rim
How do these pressures and impacts differ in the coastal environments of different countries,
for example in developing (e.g. Bangladesh in the northern IO) versus developed countries
(e.g. western Australia in the southern IO). How in turn does sea level rise affect coastal
development and human populations in these areas In many areas, coastal development
is synonymous with urbanization and industrial development. What will be the impacts of
urbanization (e.g. increased sewage discharge and changes in water use) and industrial
development (e.g. construction of dams, desalination plants, and power plants) on coastal
marine ecosystems How, specifically, will changes in material transport (riverine, groundwater,
and aeolian) and deposition (e.g. volatile organic compounds, nutrients, sediments, and
heavy metals) alter coastal marine environments Coastal development usually involves
changes in land use. What will be the impacts of land use changes (e.g. agriculture,
deforestation, desertification) on coastal marine ecosystems in the IO
Similarly, coastal development involves changes in water use, i.e. diversion and rerouting of
water supplies for both urban and agricultural purposes. How will future increases in water
use change the seasonal and spatial distribution of freshwater inputs and how will subsequent
decreases in discharge affect circulation, productivity, food web structure and biogeochemical
processes in coastal waters These questions are particularly relevant to marginal seas where
alterations in freshwater inputs can have major impacts (e.g. the damming of the Indus River
and the salinization of the delta). More generally, how are the river loads and the stoichiometric
ratios of C, N, P and Si changing in the IO What is the role of river carbon and nutrient export,
and what is the impact of changing river loads and modified stoichiometric ratios on open
ocean biodiversity and primary production through changing food web structure in the coastal
seas
Human activities also influence atmospheric transport of particulate matter and deposition
in coastal and open ocean waters. In general, how do natural changes (e.g. seasonal and
interannual) affect marine IO environments through deposition of nutrients and minerals and
scavenging of POC and DOC Both natural and anthropogenic aerosols can have particularly
high concentrations in the northern IO. How important is aeolian input to biogeochemical
cycles (e.g. Fe, N, Si, P) Is this input disproportionately important compared to other
oceans How does dust deposition transmit through the water column and the pelagic food
web and ultimately impact benthic-pelagic coupling in coastal waters and shallow seas How
does potential increasing monsoon intensity (Goes et al., 2005) affect air mass trajectories,
aerosol and mineral fluxes, and how will these processes affect the biological production and
biogeochemical cycles in the northern IO How are aerosols (both natural and anthropogenic)
affecting the incident radiation into the IO and what are the biogeochemical and ecosystem
consequences How will all of these influences change in the future climate For example,
how will changes in the frequency of extreme weather patterns (drought/floods, fires) affect
sources of mineral dust to marine environments in the IO
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