Environmental Engineering Reference
In-Depth Information
eutrophication due to increased fertilizer or wastewater runoff have lead to the
development of hypoxic conditions in systems already susceptible due to vertical
stratification of the water column [
34
]. Thus, the disruption in the typical oxygen
cycle and the lack of an anaerobic respiration mechanism in most marine organisms
can result in serious consequences for the composition and productivity of the
marine food web community in these hypoxic zones.
Future Directions
Studies of Biogeochemical Cycles
In the past two decades, a number of large, interdisciplinary programs were
conducted to obtain biogeochemical data on appropriate time and space scales so
that mathematical models of global climate change can accurately represent the
complex processes of elemental cycles. One such program, the Joint Global Ocean
Flux Study (JGOFS), which occurred from 1987 to 2003, was international in
scope, and undertook coordinated, multidisciplinary, international studies in the
equatorial Pacific, the north Atlantic, the Arabian Sea, and the Southern Ocean, and
coordinated multidisciplinary national programs in a range of coastal and open
ocean environments. The JGOFS project was designed to assess the carbon cycle,
but because all elemental cycles are closely linked, insights were gained into the
understanding of nitrogen, silicon, and iron cycles as well. The JGOFS program
also had a significant synthesis and modeling component that was intended to
integrate the data sets from the multidisciplinary studies and to develop mathemati-
cal models of increased complexity and biological realism. In addition to providing
a wealth of publicly available data, the JGOFS program served as a model for large,
multidisciplinary studies of ocean processes.
The results and understanding from the JGOFS program provided the basis for the
Integrated Marine Biogeochemistry and Ecosystem Research (IMBER) Project,
which was initiated in 2001 by the International Geosphere-Biosphere Program
and the Scientific Committee on Oceanic Research. The science goals of the
IMBER project extend the investigation of marine biogeochemical cycles to include
the influence of feedbacks with marine food webs and the consequences for marine
ecosystems. Central to the IMBER goal is the development of a predictive under-
standing of how marine biogeochemical cycles and ecosystems respond to complex
forcings, such as large-scale climatic variations, changing physical dynamics, car-
bon cycle chemistry and nutrient fluxes, and the impacts of marine harvesting.
IMBER science is making new advances in understanding marine systems by
bringing together the natural and social science communities to study key impacts
and feedbacks between the marine and human systems. The emerging recognition of
human interactions as integral parts of marine ecosystems is providing the direction
for future integrative research designed to understand and sustain ocean systems as
environmental change and its associated uncertainties occur.
