Index 295a polarizing cation 21
regeneration in deep waters 222 , 224 , 231
resistant to photodissociation 2
a semi-conductor 18
transported as undissociated silicic acid 145
SiO 4 tetrahedron 70, 70 , 73
smectite clays126–7
cation exchange capacity 112, 112 , 126
CIA values 108, 108
develop in poorly drained sites 109
use of pillaring agents 126
smectite group 92, 92
smog
damaging to stonework 55
and fog, affects health 47–8
London (primary pollution) 46–8, 52
see alsophotochemical smog
smoke 55
and fog 47
from diesel engines 56
see alsosoot
sodium chloride (NaCl)
an ionic solid 20
precipitation of 195
sodium (Na) 145, 145 , 212–13
Znumber 15
soil orders 13, 115
soil pH, and ion exchange 111–12
soil structure and classification 112–19
Food and Agriculture Organization (FAO) classification
113
soil horizons 113
soil profiles, idealized 113, 114
US Department of Agriculture classification 113
soil washing126–7
soils
active nitrogen chemistry in 41–2
with argillic horizons 113, 114 , 116
biotic 79, 104
CEC indicates availability of essential trace metals
112
formation of 93–104
climate 94, 96–7
influence of organisms 99, 102–4
key factors 93–4, 95
parent (bedrock) material 94
relief 97–9
vegetation 99
wider controls on 104–9, 110
with gley horizons 117–19
interface between atmosphere and lithosphere 68,
70
organic contaminants in 119–25
spodosols (podzols) 113, 115–16, 117 , 199
soilwater, acidification of 156
soilwater pH 49 , 79, 151
solar energy, utilized to synthesize organic material 9
solar radiation 7, 8, 8
solubility, of compounds 121 , 122
solubility product, mineral solubility and saturation index
107
soot
diesel 56
from biomass burning and cooking stoves 42 , 53
from forest fires 41
South Pole, record of atmospheric CO 2 values 240–2,
241
spilites 212
spodosols (podzols) 113, 115–16, 117 , 199
chelation of ‘free’ metal ions 115
stable isotope ratios 269
stable isotopes 3
stratification
in lakes 161–2, 162
in tropical waters220–1
see alsothermal stratification
stratosphere
chemistry of 58–64
destruction of ozone (O 3 ) 60–1
formation of ozone (O 3 ) 9, 59–60
gases reacting with atomic oxygen 45
human-induced decrease in ozone 258
impact of small amount of trace pollutants 35
reactions involving atomic oxygen 59
a reservoir of smaller size 58
rise in temperature gives stability 33
sugars, in biopolymers 101
sulphate
damaging to calcareous stonework 55
tracer of acid mine drainage 159
sulphate reduction 103, 103 , 163
in continental margin sediments 206–7
sulphide oxidation, and acid mine drainage 156–8
sulphides 206 –7
sulphite 207
sulphur (S)
a contaminant in some coals 46–7, 47
deposition from atmosphere increased 263, 265
and early creation of organic matter 9
in hydrothermal reactions 213–14
mass balance 264 , 266
stable isotope standard, CDT (Canyon Diablo troilite)
269
volatile 263
volcanic emissions remain unchanged 263, 264
sulphur compounds, oxidized 57
sulphur cycle 11, 262–74
and atmospheric acidity 265–71
changes in 263, 264
and climate 271–4
global, and anthropogenic effects 262–5
sulphur dioxide (SO 2 )47
and the acidification of rain 57, 58 , 265–71
removal of from an air parcel 57, 59
sulphur isotope ratios 269–71
use of Canyon Diablo troilite (CDT) standard 269,
269
sulphur pollution, in the urban atmosphere 46 –7
sulphuric acid
in the atmosphere 265, 266
in smog 47
surfactants126 –7