An Introduction to Environmental Chemistry
between seawater and basaltic ocean crust. However, estimates of the element fluxes involved in these processes are uncertain, m ...
Hydrothermal reactions as major ion sinks Of the major elements, the case for magnesium removal from seawater during hydrotherma ...
on a geological timescale is dominated by the formation of evaporites (Section 6.4.2). Hydrothermal reactions as major ion sourc ...
the amount of SO 42 - entering the higher-temperature (>250°C) parts of the hydrothermal system. At these high temperatures t ...
eqn. 6.19 This reaction shows that reverse weathering is exactly opposite to continental weathering reactions, which consume CO ...
6.5 Minor chemical components in seawater 6.5.1 Dissolved gases Gases dissolve from the atmosphere into the oceans according to ...
iron- and manganese-rich. These sediments derive from FeS particles that pre- cipitate in the ‘black smoke’ plume as the hot and ...
6.5.3 Conservative behaviour Elements with conservative behaviour are characterized by vertical profiles (similar to major ion p ...
with the organic tissue of organisms, while silicon and calcium (Ca) are cycled as skeletal material. The decomposition of organ ...
220 Chapter Six Box 6.6 Oceanic primary productivity The rate of growth of phytoplankton (primary productivity) in the oceans is ...
The Oceans 221 utilization in proteins. When phytoplankton die they decompose, releasing the nitrogen as ammonium (NH 4 +) hence ...
Section 5.5.1) have little effect on oceanic NO 3 - concentration, assuming that NO 3 - is effectively mixed throughout the ocea ...
The Oceans 223 PO 4 3– (μmol l–1) NO ( 3 μmol l –1) 50 0.0 1.0 3.0 4.0 10 20 2.0 40 30 0 Fig. 6.21Global relationship between ...
is an example (Fig. 6.23). These profiles arise because the inputs of these ele- ments are all in the surface waters, producing ...
removed mainly in estuaries, where suspended solid concentrations are high (Section 6.2.1). Consequently, the atmosphere provide ...
system still adjusting to rapid changes in Pb^2 +input. Although it is regrettable that humans have caused global-scale lead pol ...
significant removal process for a number of elements, particularly vanadium (V), phosphorus (P), arsenic (As) and chromium (Cr) ...
228 Chapter Six Fe (nmol l–1) Depth (km) 0 0 0.2 0.6 0.8 4.0 3.0 0.4 3.5 0.5 1.5 1.0 2.0 2.5 Fig. 6.25Dissolved iron concentrati ...
these areas has come from a recent experiment in which iron was added to a small patch of ‘chemically labelled’ surface water in ...
cold, oxygen-rich water, displacing the bottom water in its path. The displaced bottom water is forced to move upwards slowly, s ...
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