Arid Dune Ecosystems


Book Description

Sand dune dynamics play a key role in many arid deserts. This volume provides a thorough analysis of a specific sand dune ecosystem, the Nizzana site in the Middle East’s Negev Desert. Describing its climate, as well as its geophysical/geochemical soil properties and ecology, this brilliant work draws out the relationships between the site’s ecological and geomorphological processes, based on long-term monitoring, in situ experiments and satellite imagery.




Arid Dune Ecosystems


Book Description

Sand dune dynamics play a key role in many arid deserts. This volume provides a thorough analysis of a specific sand dune ecosystem, the Nizzana site in the Middle East’s Negev Desert. Describing its climate, as well as its geophysical/geochemical soil properties and ecology, this brilliant work draws out the relationships between the site’s ecological and geomorphological processes, based on long-term monitoring, in situ experiments and satellite imagery.




Plants of Desert Dunes


Book Description

Based on three decades of field experience in southwest Asia, southern Africa, and the southwest United States, the author summarizes the major adaptations of plants to desert dunes. This integrative study of plant and diaspore morphology, reactive growth, life cycles, and environmental factors explains and predicts plant distribution. Many kinds of dune syndromes, plant case studies and vegetation transects are discussed and illustrated to clarify the significance of adaptations to specific habitat factors. Although the focus is on vascular plants, the development of microbiotic soil crust, its function, and its composition are discussed as well.







Arid Ecosystems


Book Description




Geomorphology of Desert Dunes


Book Description

Sand dunes are a globally important depositional landform and sedimentary system. Their origins and dynamics are important in understanding how deserts have evolved in response to climate change and changes in sand supply and mobility, and how they will continue to evolve in the future. This book provides a state-of-the-art review of the characteristics of desert dunes and their sediments, and explores their dynamics on timescales from days to millennia as they respond to changes in wind speed and direction, precipitation and sand supply. This extensively revised edition reflects the advances in our understanding of desert dunes, their dynamics and history; and covers recent developments including the luminescence dating revolution, ground penetrating radar and advances in numerical modeling. Also covering dunes on Mars and Titan, this authoritative reference is a must-have for researchers and graduate students working on desert dunes and aeolian geomorphology.




Sand Dunes of the Northern Hemisphere


Book Description

This book in two volumes, and with a foreword by the renowned Professor M.A.J. Williams, draws on evidence from coastal and inland regions, including desert dunes, wind-blown dust, river and lake sediments, glacial moraines, plant and animal fossils, isotope geochemistry, soils and prehistoric archaeology to better understand the genesis and development of dunes systems in selected northern hemisphere sand dunes from Asia, Africa and the Middle East regions. The collection of research papers and case studies that are presented in this book provide the reader with a wealth of information about the distribution and types of sand dunes and an insight into the complexity of sand dune formation, migration and management. Research in many countries across the northern hemisphere shows that dunes, whether coastal or inland, are under pressure around the world. Much of the pressure comes from human activities, and the anthropogenic disturbance, when coupled with global warming and alterations to the amount, frequency and temporal distribution of precipitation could lead to more serious management challenges in the future. There is much that we still need to find out about the origin, genesis and development of sand dunes so that they can be managed better. The difficult and complex questions being repeatedly raised can be answered only by interdisciplinary endeavours. Geomorphologists, geologists, palaeontologists, climatologists, ecologists, and others, can work together on research projects that better define the origin, evolution and development of dunes, both inland and along the coasts. Many chapters in this book attempt to reconstruct past climatic changes in deserts and their margins at a variety of scales in space and time in the expectation that such information might assist in preparing us for future global warming and drying.




Sand Dunes of the Northern Hemisphere: Distribution, Formation, Migration and Management


Book Description

Volume 2 of the book ‘Sand Dunes of the Northern Hemisphere’ is sub-titled Characteristics, Dynamics and Provenance of Sand Dunes in the Northern Hemisphere. It brings together a vast body of information and insight into sand dune and desert systems from North Asia, Central Asia, North Africa and the Middle East. Chapters from the Russian Federation include studies on dune systems within the permafrost zone and there is a case study from temperate zone dune system in coastal Japan. Volume 2: Characteristics, Dynamics and Provenance of Sand Dunes in the Northern Hemisphere of 16 chapters in three Parts, focusses on Saharan Africa, Egypt, and Middle East and gives attention to sand mobility and encroachment with case studies from a number of countries where these matters are of concern. We also include chapters on the remote dunes in the permafrost zone and in the hyper-arid deserts of Iran. Case studies are used to highlight the characteristics of dunes and their interaction with humans in several widely divergent settings. Volume 2 concludes with some musing on the value of study of the past as key to the future and speculates on what the future might hold in the light of a warmer and drier Earth and a rise in sea level that threaten large tracts of low-lying land with marine incursions and destruction from storm surge. PART 4 Sand Mobility and Encroachment The seven chapters in this Part examine the real-world impact of sand encroachment and dune migration on people and their economic activities and the health, welfare and financial implications related to destruction of infrastructure, including human habitations. PART 5 Sand Dune Landscapes Distribution, Formation and Management Seven Case studies from several geographic regions in Africa, the Middle East, north-east Asia are presented here to demonstrate the underlying mechanisms in dune formation and the diverse approaches to their management. Human impacts such as sand mining, tourism development, combine with natural forces like climate variability to challenge the realization of an optimum management strategy. PART 6 Concluding Thoughts: Coping with an Unknown Future from a Little-known Past The two chapters in Part 6 have special roles. We are privileged to publish new research findings that are summarized here in Chapter 38 from extensive and detailed work conducted in the Kyzyl Kum, and Karakum sand seas of Central Asia. There is a strong belief that further study of the little-known past such as revealed in this study could unlock clues as to what a future Earth might look like. This leads on to speculation in Chapter 39 about the implications of what we already know about global change (not only climate change) and the impact of the Anthropocene on the dune systems, both inland and coastal. Sea level rise, marine incursions and an increase in extreme weather events will affect dune systems and sand seas on the Northern Hemisphere (and beyond).




Microbial Ecology of Arid Terrestrial Systems


Book Description

Water is usually referred to as the ‘Molecule of Life’. It constitutes the most abundant molecule in living (micro)organisms and is also essential for critical biochemical reactions, both for the global functioning and maintenance of Ecosystems (e.g., Photosynthesis) and individual (microbial) cells (e.g., ATP hydrolysis). However, most of Earth’s terrestrial environments present deficiencies in bioavailable water. Arid environments cover around a third of the land’s surface, are found on the six continents and, with the anthropogenic desertification phenomenon, will increase. Commonly defined by having a ratio of precipitation to potential evapotranspiration (P/PET) below 1, arid environments, being either hot or cold, are characterized by scant and erratic plant growth and low densities in macro-fauna. Consequently, these ecosystems are microbially mediated with microbial communities particularly driving the essential Na and C biogeochemical cycles. Due to the relatively simple trophic structure of these biomes, arid terrestrial environments have subsequently been used as ideal ecosystems to capture and model interactions in edaphic microbial communities. To date, we have been able to demonstrate that edaphic microorganisms (i.e., Fungi, Bacteria, Archaea, and Viruses) in arid environments are abundant, highly diverse, different from those of other terrestrial systems (both in terms of diversity and function), and are important for the stability and productivity of these ecosystems. Moreover, arid terrestrial systems are generally considered Mars-like environments. Thus, they have been the favored destination for astro(micro)biologists aiming to better understand life’s potential distribution and adaptation strategies in the Universe and develop terraforming approaches. Altogether, these points demonstrate the importance of significantly improving our knowledge in the microbial community composition (particularly for Fungi, Archaea and Viruses), assembly processes and functional potentials of arid terrestrial systems, as well as their adaptation mechanisms to aridity (and generally to various other environmental stresses). This Research Topic was proposed to provide further insights on the microbial ecology of hot and cold arid edaphic systems. We provide a detailed review and nine research articles, spanning hot and cold deserts, edaphic, rhizospheric, BSC and endolithic environments as well as culture-dependent and -independant approaches.




Arid and Semi-Arid Geomorphology


Book Description

Based on four decades of research by Professor Andrew Goudie, this volume provides a state-of-the-art synthesis of our understanding of desert geomorphology. It presents a truly international perspective, with examples from all over the world. Extensively referenced and illustrated, it covers such topics as the importance of past climatic changes, the variability of different desert environments, rock breakdown, wind erosion and dust storm generation, sand dunes, fluvial and slope forms and processes, the role of the applied geomorphologist in desert development and conservation, and the Earth as an analogue for other planetary bodies. This book is destined to become the classic volume on arid and semi-arid geomorphology for advanced students and researchers in physical geography, geomorphology, Earth science, sedimentology, environmental science and archaeology.