406
M.e. Gennaro . S. Angelino
In the study of eutrophycation processes the determination of nutrient-anions (the
biogenic salts: NO;, NOi", phosphate, sulfate, silicate) is very important, since their
amounts are related to the population of autotrophic organisms, which are mainly
responsible for the production of organic matter from the inorganic. In particular NOl",
an intermediate stage in the nitrogen cycle, may occur in waters as a result ofbiological decompositions of proteinaceous material and is an index of organic pollution. In
oxygen-poor conditions, autotrophic organisms are able to take oxygen from the reduction of NO; to NOl". Then, when nitrate is not available anymore, oxygen is taken
from sulfate with production of sulfide, whose presence indicates therefore anoxic
water conditions. It follows that nitrate and sulfide can not be simultaneously present
in lagoon water, unless interchanges between different waters have taken place
(Manahan 1994; Grasshoff et al.1983; Riley 1989; Riley and Chester 1971; Carpenter and
Capone 1984). These considerations give an example of the complex and competitive
chemical and biological equilibria naturally present in sea-water and an idea of the
difficulty of preparing good laboratory models or reference solutions. On the other
hand, analytical chemistry, devoted to the determination both of natural constituents
and xenobiotic compounds, requires the definition of a "reference status" of the water
to be used during the development of new analytical methods and for speciation studies (De Stefano et al. 1994; Demianov et al. 1995).
Considering all the interactions and their implications for ocean management is a
challenge, because they operate on global scales and often require long-term experiments, often done in remote locations. But a global view is emerging, thanks to increasing satellite coverage, new techniques and measurement campaigns. The large
scale interactions between ocean biology and chemistry have been the focus of a recent issue of Science (Uppenbrink et al. 1998). This issue illustrates how bioinorganic
chemistry and use of trace elements by marine organisms can affect the cycling of these
elements, how recent satellite data and high quality monitoring allow a global assessment of primary production and a better view of carbon and nutrient cycling, and
how long term studies in the Pacific Ocean are giving insight into the effects of climate change on marine ecosystem and chemistry. The awareness and availability of
high-quality global data have begun to reveal the extent to which humans have altered
the biology and the chemistry of the ocean. This increased awareness and the recognition of many remaining uncertainties prompted the United Nations to proclaim 1998
as the Year of the Ocean. Strong investment and the finest international scientific collaboration are needed worldwide to support pending scientific research: the aim is
improving the health and the productivity of coastal oceans, sustaining ocean ecosystems, predicting climate variations and modernising ocean observational capabilities.
22.1.2
(hemometries: A Helpful Tool in the Investigation of the Marine Ecosystem
The techniques and the methods for accurate and sensitive analytical determinations
of chemical species in complex matrices have been greatly improved in the last years,
and the instrumentation available can lead to the production in relatively low times
of enormously large data sets. What can be further improved is the development of
strategies able to extract and interpretate all the information contained in these data.
The use of multivariate analysis methods able to simultaneously treat a large number
M.e. Gennaro . S. Angelino
In the study of eutrophycation processes the determination of nutrient-anions (the
biogenic salts: NO;, NOi", phosphate, sulfate, silicate) is very important, since their
amounts are related to the population of autotrophic organisms, which are mainly
responsible for the production of organic matter from the inorganic. In particular NOl",
an intermediate stage in the nitrogen cycle, may occur in waters as a result ofbiological decompositions of proteinaceous material and is an index of organic pollution. In
oxygen-poor conditions, autotrophic organisms are able to take oxygen from the reduction of NO; to NOl". Then, when nitrate is not available anymore, oxygen is taken
from sulfate with production of sulfide, whose presence indicates therefore anoxic
water conditions. It follows that nitrate and sulfide can not be simultaneously present
in lagoon water, unless interchanges between different waters have taken place
(Manahan 1994; Grasshoff et al.1983; Riley 1989; Riley and Chester 1971; Carpenter and
Capone 1984). These considerations give an example of the complex and competitive
chemical and biological equilibria naturally present in sea-water and an idea of the
difficulty of preparing good laboratory models or reference solutions. On the other
hand, analytical chemistry, devoted to the determination both of natural constituents
and xenobiotic compounds, requires the definition of a "reference status" of the water
to be used during the development of new analytical methods and for speciation studies (De Stefano et al. 1994; Demianov et al. 1995).
Considering all the interactions and their implications for ocean management is a
challenge, because they operate on global scales and often require long-term experiments, often done in remote locations. But a global view is emerging, thanks to increasing satellite coverage, new techniques and measurement campaigns. The large
scale interactions between ocean biology and chemistry have been the focus of a recent issue of Science (Uppenbrink et al. 1998). This issue illustrates how bioinorganic
chemistry and use of trace elements by marine organisms can affect the cycling of these
elements, how recent satellite data and high quality monitoring allow a global assessment of primary production and a better view of carbon and nutrient cycling, and
how long term studies in the Pacific Ocean are giving insight into the effects of climate change on marine ecosystem and chemistry. The awareness and availability of
high-quality global data have begun to reveal the extent to which humans have altered
the biology and the chemistry of the ocean. This increased awareness and the recognition of many remaining uncertainties prompted the United Nations to proclaim 1998
as the Year of the Ocean. Strong investment and the finest international scientific collaboration are needed worldwide to support pending scientific research: the aim is
improving the health and the productivity of coastal oceans, sustaining ocean ecosystems, predicting climate variations and modernising ocean observational capabilities.
22.1.2
(hemometries: A Helpful Tool in the Investigation of the Marine Ecosystem
The techniques and the methods for accurate and sensitive analytical determinations
of chemical species in complex matrices have been greatly improved in the last years,
and the instrumentation available can lead to the production in relatively low times
of enormously large data sets. What can be further improved is the development of
strategies able to extract and interpretate all the information contained in these data.
The use of multivariate analysis methods able to simultaneously treat a large number