A usually triangular mass of sediment, especially silt and sand, deposited at the mouth of a river. Deltas form when a river flows into a body of standing water, such as a sea or lake. The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mif...
The students organized themselves into five groups: mechanical, electrical, software, science and business. Collectively, they designed, built and programmed the rover while gaining the opportunity to compete in the competition. The UW Team earned the opportunity to compete for the third straight year...
in shape; he is often given credit for first using the Greek letter Δ (delta) to describe it. Although many of the world’s deltas are deltoid, or triangular, in shape, notable exceptions exist. In most cases, the delta shape is controlled by the outline of the water body being ...
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Natural background levels in groundwater in the Pearl River Delta after the rapid expansion of urbanization: A new pre-selection methodGuanxing Huang a bLixin Pei cLiangping Li dChunyan Liu a
The water-town settlements in the East River Delta of China engage with the aquatic environment, establishing a comprehensive cultural–ecological system. However, rapid urbanization challenges the structural integrity of water-town settlements. Focusing on the East River Delta as the study area, we ...
This river has nourished civilizations for millennia. Now it’s drying up, under attack from dam building, overfishing, and sand mining.
Water accessibility assessment (WAA) is very important to the ecological restoration of freshwater wetlands and water resources management due to an intensive human disturbance. This paper develops a quantitative methodology for WAA in the Yellow River Delta National Nature Reserve (YRDNNR), from ...
Most deltas in the world are facing the threats of erosional retreat of the shoreline and land loss. Threats came from the combined influence of human activities such as damming in the drainage basin and extraction of natural gas, oil, and water in the coastal area; and natural processes ...
Radiocarbon-dated facies in the cores serve to calculate long-term averaged subsidence rates for the Holocene section: 0.1 to 3.0 mm/year on land, and 1.6 to 4.4 mm/year at sea. This preliminary information is vital for planning coastal protection (erosion, salt water intrusion) in this ...