Following Potter's classification, arid and semiarid regions are those whose precipitation to evaporation (P/E) ratios are smaller than 0.5 and between 0.5 and 1.0, respectively. In addition to a lower net precipitation rate, rainfalls are typically infrequent and of short duration; high-intensity...
The North American Deserts & Deserts of the World Hot Deserts - Cold Deserts In most modern classifications, the deserts of the United States and northern Mexico are grouped into four distinct categories. These distinctions are made on the basis of floristic composition and distribution -- the spe...
According to some definitions, any environment that is almost completely free of plants is considered desert, including regions too cold to support vegetation—i.e., “frigid deserts.” Other definitions use the term to apply only to hot and temperate deserts, a restriction followed in this accou...
The second-largest desert is the Arctic Polar Desert. It extends over parts of Alaska, Canada, Greenland, Iceland, Norway, Sweden, Finland, and Russia. It has a surface area of about 5.4 million square miles.McMurdo Dry Valleys: The largest deserts on Earth are in the polar regions. ...
Desert Regions are Familiar faces in many pages of History of the world. The Earliest civilizations and two of the world’s major Religions were born here. This publication “Environment, People and Development: Experiences from Desert Ecosystems” Highlights some of the Basic and technologically ref...
In many regions of the world a combination of climatic factors and human activities are believed to be causing desertification. Regions at risk have the longest history of agriculture—from North Africa to China—and large areas of Australia and central North America. Paleo-deserts, large sandy ma...
Aboutone billion people live in the desert regionsof our Earth. The largest desert cities are Cairo in Egypt and Lima in Peru. There arehot deserts such as the Sahara Desert and cold deserts such as the Gobi Desertor the deserts of our polar regions. ...
The Life-Givers of the Desert:Oases throughout the World Oases(绿洲) have had a strong influence on the development of society in desert regions.Aspects of trade as well as military and political power have all been impacted by oases.Merchants have relied on these fertile zones(1)___(get)...
Phylogenetic and Physiological Diversity of Bacteria Isolated from Puruogangri Ice Core The microbial abundance, the percentage of viable bacteria, and the diversity of bacterial isolates from different regions of a 83.45-m ice core from the P... XF Zhang,TD Yao,LD Tian,... - 《Microbial Ecol...
Desert Biology: Special Topics on the Physical and Biological Aspects of Arid Regions, Volume II records the conditions and life in the arid regions of the world. This book discusses the hydrogeology of arid regions, desert soil surfaces and classes, and physical and vegetational aspects of the ...