Preface ........................................................ xi
List of figures ................................................ xv
List of tables ................................................ xxi
List of abbreviations and acronyms .......................... xxiii
List of authors ............................................. xxvii
List of contributors ......................................... xxix
1 Cretaceous and Tertiary climate change and the past
distribution of megathermal rainforests ...................... 1
1.1 Introduction ............................................ 1
1.2 Differences between Quaternary and Tertiary
megathermal forests ..................................... 3
1.3 Late Cretaceous expansion of megathermal forests ........ 5
1.4 Megathermal rainforests during the Early Tertiary
period of greenhouse climate ............................ 8
1.5 Middle Eocene to Oligocene climates .................... 11
1.5.1 General trends .................................. 11
1.5.2 Climate change in low latitudes ................. 13
1.6 Early and earliest Middle Miocene, return of
greenhouse climates .................................... 14
1.6.1 General trends .................................. 14
1.6.2 Climate change in low latitudes ................. 16
1.7 Later Middle Miocene to Pliocene, global cooling and
retraction of megathermal rainforests to the tropics ... 18
1.8 Trends in rainforest diversity based on the
palynological record ................................... 20
1.9 Scenario for rainforest evolution and diversification .. 22
1.10 References ............................................. 24
2 Andean montane forests and climate change ................... 33
2.1 Introduction ........................................... 33
2.2 Tectonic changes and the rise of the Andes ............. 34
2.3 Sensitivity and quantifying cooling .................... 35
2.4 Sites in space and time ................................ 37
2.5 Quaternary interglacials ............................... 39
2.6 The last glacial period ................................ 40
2.7 Deglaciation ........................................... 43
2.8 The Holocene ........................................... 45
2.9 The past as a key to the future ........................ 46
2.10 Conclusions ............................................ 47
2.11 References ............................................. 48
3 Climate change in the lowlands of the Amazon Basin .......... 55
3.1 Introduction ........................................... 55
3.2 Evidence of temperature change ......................... 57
3.3 Evidence of precipitation change ....................... 60
3.4 Changes in atmospheric CO2 ............................. 61
3.5 The periodicity of change .............................. 61
3.6 The type of forest ..................................... 64
3.7 Phylogenies ............................................ 67
3.8 Holocene climate change ................................ 70
3.9 Conclusions ............................................ 70
3.10 References ............................................. 71
4 The Quaternary history of far eastern rainforests ........... 77
4.1 Introduction ........................................... 77
4.1.1 Present setting ................................. 77
4.1.2 Nature of the evidence .......................... 79
4.2 Modern pollen sampling ................................. 80
4.3 Regional taxon representation .......................... 86
4.4 Long-term patterns of change ........................... 89
4.4.1 The South China Sea region ...................... 89
4.4.2 The Coral Sea region ............................ 92
4.5 The later Pleistocene .................................. 96
4.6 The Last Glacial Maximum (LGM) to Holocene ............. 99
4.6.1 Last Glacial Maximum ............................ 99
4.6.2 The Pleistocene-Holocene transition ............ 104
4.6.3 The Holocene ................................... 105
4.7 Vegetation responses to cyclical forcing .............. 106
4.8 General discussion and conclusions .................... 108
4.9 References ............................................ 109
5 Rainforest responses to past climatic changes in tropical
Africa ..................................................... 117
5.1 Introduction .......................................... 117
5.2 Vegetation units within the Guineo-Congolian
rainforest ............................................ 118
5.1 Hygrophilous coastal evergreen forest ................. 118
5.2.2 Mixed moist semi-evergreen ..................... 119
5.2.3 Single-dominant moist evergreen and semi-
evergreen ...................................... 119
5.2.4 Drier peripheral semi-evergreen forest ......... 120
5.2.5 Secondary rainforest ........................... 120
5.2.6 Swamp forest ................................... 121
5.2.7 Edaphic and secondary grasslands ............... 121
5.2.8 Transitional and Afromontane evergreen
forests ........................................ 121
5.3 Modern pollen rain studies ............................ 122
5.3.1 From coastal evergreen to drier semi-
evergreen forests in Cameroon .................. 122
5.3.2 Mixed moist semi-evergreen forest .............. 126
5.3.3 Drier peripheral semi-evergreen forest ......... 126
5.3.4 Forests of the Mayombe ......................... 132
5.3.5 Coastal forests ................................ 134
5.3.6 Swamp forest ................................... 135
5.4 Quaternary history .................................... 136
5.4.1 Ice-age record ................................. 136
5.4.2 Holocene record ................................ 146
5.4.3 History of the rainforest during the last
5,000 years .................................... 155
5.4.4 The oil palm, evidence for human impact? ....... 156
5.4.5 The last historical period (Gabon) ............. 158
5.5 Conclusions ........................................... 161
5.6 References ............................................ 163
6 Tropical environmental dynamics: A modeling perspective .... 171
6.1 Introduction .......................................... 171
6.2 Biosphere modeling .................................... 173
6.2.1 Biome modeling ................................. 177
6.2.2 Dynamic global vegetation models ............... 180
6.2.3 Models of biogeochemical cycles ................ 181
6.3 Climate modeling ...................................... 181
6.4 Modeling the last glacial period ...................... 183
6.5 Testing models with data .............................. 185
6.6 Practical application of model output and future
developments .......................................... 186
6.7 Conclusions ........................................... 187
6.8 References ............................................ 187
7 Prehistoric human occupation and impacts on Neotropical
forest landscapes during the Late Pleistocene and Early/
Middle Holocene ............................................ 193
7.1 Introduction .......................................... 193
7.2 Some brief comments on the Old World .................. 193
7.3 Human colonization of Neotropical forests: an
ice-age entry ......................................... 194
7.3.1 The early evidence for human occupation ........ 194
7.3.2 Pleistocene landscapes and early human
modification of them ........................... 198
7.3.3 After the Pleistocene: the origins and spread
of tropical forest agriculture during the
Early Holocene ................................. 201
7.4 Evidence for human modification of forests by
prehistoric farmers ................................... 206
7.4.1 Lake records and detecting human disturbance
in them ........................................ 206
7.4.2 Major trends and patterns of prehistoric
tropical forest modification ................... 210
7.5 Summary ............................................... 212
7.6 References ............................................ 213
8 Ultraviolet insolation and the tropical rainforest:
altitudinal variations, Quaternary and recent change,
extinctions, and biodiversity .............................. 219
8.1 Introduction .......................................... 219
8.2 Altitudinal variations ................................ 219
8.3 The Massenerhebung effect ............................. 222
8.4 Quaternary variations of vegetation ................... 223
8.5 Present and possible future trends in UV insolation
and their effects ..................................... 225
8.6 Biodiversity .......................................... 227
8.7 Conclusions ........................................... 230
8.8 References ............................................ 231
9 Climate change and hydrological modes of the wet tropics ... 237
9.1 Introduction .......................................... 237
9.2 Rainfall and hydrological regimes in the Amazon
Basin ................................................. 239
9.2.1 Rainfall distribution and seasonal rainfall
and river seasonal variability ................. 239
9.2.2 Atmospheric and hydrological water balance ..... 240
9.2.3 Maintenance of humidity and import/export of
moisture in the Amazon Basin ................... 245
9.2.4 Interannual variability: El Nino and tropical
Atlantic impacts ............................... 248
9.2.5 Decadal- and longer timescale climate and
hydrology variability .......................... 250
9.2.6 Changes in land use and impacts on Amazon
climate ........................................ 252
9.3 Projections of future changes in climate and
hydrology of the Amazon Basin ......................... 254
9.3.1 Detected changes in air temperature ............ 254
9.3.2 Future projections of changes in air
temperature .................................... 255
9.3.3 Detected and projected changes in
precipitation .................................. 255
9.3.4 Future projections of changes in
precipitation .................................. 256
9.3.5 Changes in the hydrology of the Amazon River
Basin .......................................... 257
9.4 Uncertainties in climate and hydrology variability,
long-term trends, and climate change in the Amazon
region ................................................ 260
9.5 References ............................................ 261
10 Plant species diversity in Amazonian forests ............... 269
10.1 Introduction .......................................... 269
10.2 Study site: overviews of Amazonian geography,
geology, and climate .................................. 271
10.2.1 Amazonian geography, geology, and soils ........ 271
10.2.2 Elevation ...................................... 272
10.2.3 Precipitation .................................. 273
10.2.4 Species diversity and environmental gradients .. 274
10.3 Results ............................................... 275
10.3.1 Precipitation: patterns ........................ 275
10.3.2 Latitudinal and longitudinal gradients in
Amazonian diversity ............................ 277
10.3.3 Diversity in relation to precipitation and
geology ........................................ 278
10.3.4 Elevation and diversity ........................ 281
10.4 Discussion ............................................ 281
10.4.1 Precipitation and diversity .................... 281
10.4.2 Geology and diversity .......................... 283
10.4.3 Gamma diversity and range limits along
environmental gradients ........................ 285
10.4.4 Elevation and diversity ........................ 286
10.4.5 Long-term climate change and Amazonian
diversity: a Holocene minimum in western
Amazonia? ...................................... 287
10.4.6 The mid-domain effect .......................... 287
10.4.7 Discounting migration .......................... 287
10.4.8 Future efforts ................................. 288
10.5 References ............................................ 288
11 Nutrient-cycling and climate change in tropical forests .... 295
11.1 Introduction .......................................... 295
11.2 Tropical forest soils ................................. 297
11.3 Litter inputs ......................................... 301
11.4 Decomposition ......................................... 303
11.5 Nutrient uptake ....................................... 304
11.6 Trace gas emissions ................................... 306
11.7 Summary and future directions ......................... 308
11.8 References ............................................ 309
12 The response of South American tropical forests to
contemporary atmospheric change ............................ 317
12.1 Introduction .......................................... 317
12.2 The plot network ...................................... 319
12.3 Structural changes .................................... 320
12.4 Dynamic changes ....................................... 321
12.5 Functional changes .................................... 324
12.6 What is driving these changes? ........................ 326
12.7 The future ............................................ 328
12.8 References ............................................ 329
13 Ecophysiological response of lowland tropical plants to
Pleistocene climate ........................................ 333
13.1 Introduction .......................................... 333
13.2 Ecophysiological primer ............................... 334
13.3 Independent versus interactive climate effects ........ 336
13.3.1 Global cooling ................................. 336
13.3.2 Decreased glacial precipitation ................ 337
13.3.3 Low atmospheric CO2 ............................ 338
13.3.4 Interactive effects of Pleistocene climate
and atmospheric C02 ............................ 338
13.4 Ecological responses to Pleistocene climate change .... 339
13.4.1 Expansion of C4 grasslands ..................... 339
13.4.2 Rainforest versus seasonal forest .............. 340
13.4.3 Vertical stratification of glacial forests ..... 340
13.5 Soil processes and Pleistocene climate change ......... 341
13.6 Conclusion ............................................ 342
13.7 References ............................................ 343
14 Modeling future effects of climate change on tropical
forests .................................................... 351
14.1 Introduction .......................................... 351
14.2 Bioclimatic models .................................... 353
14.3 Gap models ............................................ 356
14.4 Dynamic global vegetation models ...................... 358
14.5 Earth System models ................................... 359
14.6 Conclusion ............................................ 363
14.7 References ............................................ 363
15 Conservation, climate change, and tropical forests ......... 367
15.1 Introduction .......................................... 367
15.2 Conservation challenges ............................... 368
15.3 Conservation responses ................................ 370
15.4 Conservation strategies ............................... 372
15.5 GHG stabilization ..................................... 374
15.6 Conclusion ............................................ 376
15.7 References ............................................ 376
Subject index ................................................. 379
Species index ................................................. 393
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