294 Index
redox processes
importance of 168
see alsooxidation and reduction (redox)
re-emission (secondary emission), of POPs 278, 281
reforestation 245, 255
regional seas, increased nitrate concentrations 232–7
relief, and climate 97–9, 105
effect of steep slopes 97–8
influence of form of slope 98–9
remediation of contaminated land 129–37
remediation options 129, 131
bioremediation122–3, 131–7
chemical remediation126–7, 131
physical remediation 131
residence times 36–8
elements with nutrient-like distribution 221–3, 224
gases in the atmosphere 44–5
major ions in seawater 191–2, 192 , 216
scavenged species 224–5, 224
short, of water vapour in the atmosphere 7
sulphur compounds in the atmosphere 266–7
and variability of gases in the atmosphere 37–8, 38
respiration 41
microbial 103, 103
respiration/decomposition 243, 247
reverse weathering reactions concept 214–15
rivers
carry dissolved and particulate matter to the oceans
181
classification of dissolved ions in 147, 148 , 151
dissolved major ion composition, some major rivers
145–6, 145
draining sedimentary rocks, high total cation
concentrations 147
material transport by 68, 68
nitrate concentrations increased 237
slow-flowing, biological activity and water chemistry
161–2, 164
rubidium (Ru), beta decay of 28
rusting, chemical equation for 21
salinity 184, 190–1
defined and measured 185
of seawater, declining in spurts 191
salt particles
attract water and form aerosols 39
from sea spray, in the atmosphere 39
Salton Sea, now saltier than sea water 149–51
saturation index 107
of aragonite, effect of rising atmospheric CO 2 on 261,
262
scavenged behaviour 223–7
scavenged species all metals 224–5
sea-salt inputs, to freshwaters 146
sea-salt sulphate 263
sea-salts, airborne, removal process for Na and Cl 194
sea-to-air fluxes, of major ions 194
sealevel, global rise in 260
seawater
ability to take up excess CO 2246
alkalinity 151
chemical composition, differs from that of freshwater
181, 182, 183
chemical cycling of major ions 191–215
calcium carbonate formation 196–205
cation exchange 195–6
evaporites 194–5
hydrothermal processes 208–14
opaline silica 205–6
sea-to-air fluxes 194
decrease in pH of surface water
from increased atmospheric CO 2 260–1, 261
may affect CaCO 3 skeleton animals 261
dissolved iron concentrations 227, 228
global nitrogen–phosphate relationship 219, 223
low concentration of iron in 227
major ion budget for 194 , 214
major ion chemistry of 189, 190–1
minor chemical components 216–27
conservative behaviour 218
dissolved gases 216
dissolved ions 216–17, 218
nutrient-like behaviour 218–19, 221–3, 227
scavenged behaviour 223–7
the potassium problem: balancing the major ion budget
214–15
reservoir for CO 2 251, 253
saturated or supersaturated with CaCO 3? 196, 197–8
tropical, supersaturated with respect to calcite 197,
200–1
sedimentary mudrocks 66, 67 , 68, 253
sedimentary rocks 66
sedimentation, in estuaries 183–4
semi-conductors 18
semi-metals 17 , 18
semivolatile organic compounds (SVOCs) 274–5, 276 ,
277–8
alpha-HCH as 281
condensation of in polar environments 275
interaction with polar ecosystem 277–8
long distance transport of 275
sepiolite 212
sewage discharge 162
increases nutrient concentrations in estuaries 187
and low/zero dissolved oxygen concentrations 188
sheet silicates 75 , 76, 87–92, 104
Si : N ratio, increasing in Black Sea 169–70
Si–O bond, covalency in 21
siderite 118–19, 164
Sierra Nevada, USA, mercury releasing into surface and
groundwaters 174
Silent Spring, Rachel Carson 277
silicate minerals 68, 70–6, 94, 218
complex, weathering of 84–6
coordination of ions and the radius ratio rule 70–3
structural organization in 73–6
used by diatoms 169
silicon dioxide seeopaline silica
silicon (Si) 17, 169–70
biological removal from the oceans 194 , 203 , 205–6,
206
cycled as skeletal material 219