CONTENTS -- PREFACE -- 1: INTRODUCTION: DEFINING THE DESERT SYSTEM -- 1.1 DEFINING THE DESERT SYSTEM -- 1.1.1 PHYSICAL, BIOLOGICAL, AND TEMPORAL COMPONENTS -- 1.2 EVOLUTION OF DESERTS -- 1.2.1 GLOBAL CONSIDERATIONS -- 1.2.1.1 Subtropical high-pressure belts -- 1.2.1.2 Continental interiors -- 1.2.1.3 Polar deserts -- 1.2.2 REGIONAL CONSIDERATIONS -- 1.2.2.1 Cold-current influences -- 1.2.2.2 Rainshadow effect -- 1.2.2.3 Edaphic environments -- 1.3 INDICES OF ARIDITY -- 1.4 DESERT SURFACES -- 1.5 TECTONICALLY STABLE AND UNSTABLE DESERTS -- 1.6 DESERTS OF THE PAST -- 1.7 CHANGING HUMAN PERSPECTIVES ON DESERTS -- 2: DESERTS OF THE WORLD -- 2.1 INTRODUCTION: THE EXTENT OF GLOBAL ARIDITY -- 2.2 GLOBAL DESERTS -- 2.2.1 AFRICA -- 2.2.1.1 North Africa: the Saharan Desert and the Sahel -- 2.2.1.2 North Africa: the Somali-Chalbi Desert -- 2.2.1.3 Southern Africa: arid Madagascar -- 2.2.1.4 Southern Africa: the Karoo, Kalahari, and Namib Deserts -- 2.2.2 MIDDLE EAST AND ARABIA -- 2.2.2.1 Negev and Sinai Deserts -- 2.2.2.2 Deserts of Syria and Jordan -- 2.2.2.3 The Arabian Peninsula -- 2.2.2.4 Iran and Iraq -- 2.2.3 EUROPE -- 2.2.4 ASIA -- 2.2.4.1 Middle Asian deserts -- 2.2.4.2 Deserts of India and Pakistan -- 2.2.4.3 Deserts of China and Mongolia -- 2.2.5 SOUTH AMERICA -- 2.2.5.1 The west coast deserts: Peru-Chile, Atacama, and Sechura deserts -- 2.2.5.2 Altiplano/Puna -- 2.2.5.3 Monte Desert -- 2.2.5.4 Patagonian Desert -- 2.2.6 NORTH AMERICA -- 2.2.6.1 Chihuahuan Desert -- 2.2.6.2 Sonoran Desert -- 2.2.6.3 Mojave Desert -- 2.2.6.4 The Great Basin deserts -- 2.2.7 AUSTRALIA -- 3: THE CLIMATIC FRAMEWORK -- 3.1 INTRODUCTION: CLASSIFICATION OF DESERTS BY TEMPERATURE -- 3.2 WEATHER DATA -- 3.3 ATMOSPHERIC CONTROLS: SURFACE BOUNDARY LAYER -- 3.3.1 ATMOSPHERIC WATER VAPOR AND CLOUD COVER -- 3.3.2 RADIATION.

3.3.3 TEMPERATURE OF THE AIR, SURFACE, AND SUBSURFACE -- 3.3.3.1 Air temperature of hot deserts -- 3.3.3.2 Surface temperatures -- 3.3.3.3 Subsurface temperatures -- 3.3.4 ALBEDO -- 3.3.5 PRECIPITATION -- 3.3.5.1 Storm types and seasonality of precipitation -- 3.3.5.2 Forms of precipitation other than rainfall: fog, dew, and snow -- 3.3.5.3 Variability in precipitation -- 3.3.6 WIND -- 3.3.7 EFFECTS OF POPULATION GROWTH AND URBANIZATION ON DESERT CLIMATOLOGY -- 3.3.7.1 Air pollution -- 3.3.7.2 Heat islands -- 3.4 TEMPORAL AND SPATIAL VARIABILITY OF CLIMATIC INFLUENCES -- 3.4.1 ENSO FORCING OF DESERT CLIMATES -- 3.4.2 EXPANSION AND CONTRACTION OF THE SAHARA DESERT -- 3.4.3 THE SAHEL: LAND-SURFACE-ATMOSPHERE INTERACTIONS -- 4: THE HYDROLOGIC FRAMEWORK -- 4.1 INTRODUCTION -- 4.2 THE WATER BALANCE IN DESERTS -- 4.3 WATER BUDGETS -- 4.3.1 PRECIPITATION AND ITS ASSESSMENT: PROBLEMS IN GAUGING AND NETWORK DESIGN -- 4.3.2 INTERCEPTION -- 4.3.3 EVAPOTRANSPIRATION -- 4.3.3.1 Introduction -- 4.3.3.2 Evaporation -- 4.3.3.3 Transpiration -- 4.3.4 INFILTRATION AND SOIL WATER -- 4.3.5 GROUNDWATER, SUBSURFACE FLOW, AND SPRINGS -- 4.3.5.1 Role of groundwater in arid environments -- 4.3.5.2 Groundwater recharge -- 4.3.5.3 Groundwater quality -- 4.4 SURFACE RUNOFF AND FLOODS -- 4.4.1 CONTROLS ON RUNOFF -- 4.4.2 RUNOFF FROM SLOPES -- 4.4.3 RUNOFF IN CHANNELS -- 4.4.3.1 Ephemeral channels -- 4.4.3.2 Intermittent and perennial rivers -- 4.4.3.3 Low-flow events and the ecological effects of drought -- 4.4.4 TRANSMISSION LOSSES DURING FLOODS -- 4.5 THE CHEMICAL QUALITY OF SURFACE AND SOIL WATER -- 4.6 WATER RESOURCES -- 4.6.1 GROUNDWATER -- 4.6.2 DAMS AND RESERVOIRS -- 4.6.3 LONG-DISTANCE TRANSFER: CANALS AND AQUEDUCTS -- 4.6.4 RAINMAKING -- 4.6.5 DESALINATION -- 4.6.6 FOG-WATER COLLECTION SYSTEMS.

4.7 CASE STUDY: THE WATERS OF THE TIGRIS-EUPHRATES BASIN AND THE IMPACT OF MODERN WATER MANAGEMENT -- 5: LAKE SYSTEMS: PAST AND PRESENT -- 5.1 INTRODUCTION TO DESERT LAKES -- 5.2 TYPES OF LAKE -- 5.2.1 PERENNIAL SALT LAKES -- 5.2.2 EPHEMERAL LAKES: PLAYAS AND PANS -- 5.2.2.1 Wet (salt playas -- discharge playas) and dry (recharge playas -- claypans) systems -- 5.2.2.2 Playa degradation -- 5.2.3 PALAEOLAKE SYSTEMS: LAKES AS INDICATORS OF PAST CLIMATE CHANGES -- 5.3 LAKES OF THE GLOBAL ARID ENVIRONMENT -- 5.3.1 WESTERN NORTH AMERICA -- 5.3.2 SOUTH AMERICA -- 5.3.3 AUSTRALIA -- 5.3.4 AFRICA -- 5.3.5 ASIA -- 5.3.5.1 China and Mongolia -- 5.3.5.2 India and Pakistan -- 5.3.6 MIDDLE EAST -- 6: WEATHERING PROCESSES AND HILLSLOPE SYSTEMS -- 6.1 INTRODUCTION -- 6.2 WEATHERING -- 6.2.1 INSOLATION WEATHERING -- 6.2.2 SALT WEATHERING -- 6.2.3 FROST WEATHERING -- 6.2.4 BIOLOGICAL WEATHERING -- 6.2.5 SILT INFILTRATION -- 6.3 WEATHERING FORMS -- 6.3.1 CAVERNOUS WEATHERING/TAFONI -- 6.3.2 GNAMMAS -- 6.4 DURICRUSTS -- 6.4.1 TERMINOLOGY -- 6.4.2 SILCRETE -- 6.4.3 CALCRETE/CALICHE -- 6.4.4 GYPCRETE -- 6.4.5 SALCRETE: HALITE CRUSTS -- 6.5 DESERT VARNISH -- 6.6 HILLSLOPE PROCESSES -- 6.6.1 ROCK SLOPES -- 6.6.1.1 Hillslopes in massive rocks -- 6.6.1.2 Scarp and cuesta forms -- 6.6.2 GRAVITY-RELATED ACTIVITY: TALUS AND SCREE SLOPES AND RELATED FORMS -- 6.6.3 BADLANDS -- 6.6.3.1 Case study: Borrego Badlands, California -- 6.7 COMPOSITE SURFACES (PEDIMENTS) -- 7: DESERT SOILS AND GEOMORPHIC SURFACES -- 7.1 INTRODUCTION -- 7.2 THE NATURE OF SOILS IN ARID AND SEMIARID REGIONS -- 7.3 SOIL DESCRIPTION AND CLASSIFICATION -- 7.4 SOIL CHARACTERISTICS OF ARID REGIONS -- 7.4.1 PHYSICAL CHARACTERISTICS -- 7.4.2 THE ORGANIC CONTENT OF SOILS AND NUTRIENT AVAILABILITY -- 7.4.3 ROLE OF THE PAST -- 7.4.4 ROLE OF RELIEF AND ALTITUDE -- 7.5 INORGANIC AND BIOLOGICAL SOIL CRUSTS.

7.5.1 INORGANIC SOIL CRUSTS -- 7.5.2 BIOLOGICAL/CRYPTOBIOTIC SURFACE CRUSTS -- 7.6 SPATIAL HETEROGENEITY IN SOIL PROPERTIES AND THE ECOHYDROLOGY OF PATTERNED VEGETATION ZONES -- 7.7 SURFACE VOLUME CHANGES -- 7.7.1 THE PROPERTIES AND NATURE OF SWELLING CLAY SOILS -- 7.7.2 PATTERNED GROUND OR GILGAI -- 7.8 SURFACE TYPES: HAMADA AND STONE PAVEMENTS -- 7.8.1 HAMADA -- 7.8.2 STONE PAVEMENTS -- 7.8.2.1 Introduction -- 7.8.2.2 Description of stone pavements -- 7.8.2.3 Formation of pavements -- 7.8.2.4 The aeolian aggradation theory of pavement development -- 7.8.2.5 Pavement development as a relative-age dating tool -- 7.8.2.6 Discussion -- 8: WATER AS A GEOMORPHIC AGENT -- 8.1 INTRODUCTION -- 8.2 GROUNDWATER SAPPING IN SLOPE AND VALLEY DEVELOPMENT -- 8.3 PIPING PROCESSES IN CHANNEL AND SLOPE EVOLUTION -- 8.4 FLUVIAL PROCESSES -- 8.4.1 CHANNEL MORPHOLOGY AND CHANNEL FLOW -- 8.4.2 ALLUVIUM -- 8.4.3 SEDIMENT TRANSPORT -- 8.4.4 SEDIMENT YIELDS -- 8.5 FLUVIAL LANDFORMS -- 8.5.1 ALLUVIAL FANS -- 8.5.1.1 Introduction -- 8.5.1.2 Sediment production, transportation, and deposition -- 8.5.2 ARROYOS -- 8.5.3 GULLIES -- 8.5.4 LANDFORM ASSEMBLAGES -- 9: AEOLIAN PROCESSES -- 9.1 INTRODUCTION -- 9.2 NEAR-SURFACE FLOW -- 9.2.1 VARIATION IN WIND VELOCITY WITH HEIGHT -- 9.2.2 AIRFLOW AND SEDIMENT TRANSPORT OVER HILLS AND DUNES -- 9.3 WIND PROCESSES -- 9.3.1 AEOLIAN PARTICLES -- 9.3.1.1 Particle sizes -- 9.3.1.2 Processes of particle formation -- 9.3.2 PARTICLE ENTRAINMENT (SAND) -- 9.3.3 PARTICLE TRANSPORT -- 9.3.3.1 Modes of transportation -- 9.3.3.2 Transport rates -- 9.4 LANDFORMS OF ACCUMULATION: SAND SHEETS, ZIBAR, AND SAND STRINGERS -- 9.5 LANDFORMS OF ACCUMULATION: DUNES -- 9.5.1 INTRODUCTION -- 9.5.2 THE DEVELOPMENT OF DUNE FIELDS: PALAEO-AEOLIAN PROCESSES AND EVIDENCE FOR MULTIPLE PHASES OF ACTIVITY -- 9.5.3 DUNE REACTIVATION -- 9.5.4 INTERDUNE DEPOSITS AND LAKES.

9.5.5 DUNE PATTERNS AND CLASSIFICATION -- 9.5.6 DUNE ACCUMULATION INFLUENCED BY TOPOGRAPHIC OBSTACLES -- 9.5.6.1 Lee dunes -- 9.5.6.2 Climbing dunes, sand ramps, echo dunes, and cliff-top dunes -- 9.5.7 FORMATION OF SELF-ACCUMULATED DUNES -- 9.5.7.1 Dune initiation -- 9.5.7.2 Crescentic dunes: barchans and transverse barchanoid ridges -- 9.5.7.3 Linear dunes (seif dunes) -- 9.5.7.4 Star dunes -- 9.5.7.5 Dome dunes -- 9.5.8 VEGETATED DUNES -- 9.5.8.1 Hummock dunes, coppice dunes, or nebkhas -- 9.5.8.2 Parabolic and elongate parabolic dunes -- 9.5.8.3 Lunette dunes -- 9.5.8.4 Vegetated linear dunes -- 9.6 RIPPLES -- 10: LANDFORMS OF AEOLIAN EROSION AND DESERT DUST -- 10.1 INTRODUCTION -- 10.2 DEFLATION FEATURES: DESERT DEPRESSIONS AND PANS -- 10.3 VENTIFACTS -- 10.4 YARDANGS AND RIDGE AND SWALE SYSTEMS -- 10.5 DESERT DUST -- 10.5.1 DEFINITIONS -- 10.5.2 ENVIRONMENTAL ROLE AND IMPACTS OF DUST -- 10.5.2.1 Effects on marine and terrestrial ecosystems -- 10.5.2.2 Relationship to soil development and earth surface processes -- 10.5.2.3 Impact of dust on climate, weather, and air quality -- 10.5.2.4 Dust storms and vehicular accidents -- 10.5.3 DUST ENTRAINMENT, TRANSPORT, AND DEPOSITION -- 10.5.3.1 Climatic factors in dust entrainment -- 10.5.3.2 Surface factors: vegetation, crusts, and the availability of sand -- 10.5.3.3 Anthropogenic activity -- 10.5.4 CLIMATIC EVENTS ASSOCIATED WITH BLOWING DUST: SCALES OF ACTIVITY -- 10.5.5 FREQUENCY OF BLOWING DUST: INTERANNUAL, SEASONAL, DIURNAL -- 10.5.6 DUST-SOURCE AREAS -- 11: PLANT COMMUNITIES AND THEIR GEOMORPHIC IMPACTS -- 11.1 INTRODUCTION: CHARACTERISTICS OF DESERT ECOSYSTEMS -- 11.2 ADAPTATIONS TO DESERT CONDITIONS -- 11.2.1 ADAPTATIONS TO TEMPERATURE -- 11.2.2 WATER USE BY PLANTS -- 11.2.3 REPRODUCTION -- 11.2.4 NUTRIENT CYCLING -- 11.2.5 SALT ADAPTATION -- 11.3 PLANT COMMUNITIES AND ECOTONES.

11.3.1 EVERGREEN SHRUBS.