River deltaA river delta is a landform shaped like a triangle, created by the deposition of sediment that is carried by a river and enters slower-moving or stagnant water. This occurs when a river enters an ocean, sea, estuary, lake, reservoir, or (more rarely) another river that cannot carry away the supplied sediment. It is so named because its triangle shape resembles the Greek letter Delta. The size and shape of a delta are controlled by the balance between watershed processes that supply sediment, and receiving basin processes that redistribute, sequester, and export that sediment.
Yellow RiverThe Yellow River is the second-longest river in China, after the Yangtze River, and the sixth-longest river system in Earth at the estimated length of . Originating at an elevation above 15,000 feet (4,600 metres) in the Bayan Har Mountains, it empties into the Bohai Sea. The Yellow River's basin was the birthplace of several ancient civilizations. The yellow sediments were carried downstream from the Loess Plateau. There are frequent devastating floods and course changes produced by the continual elevation of the river bed, sometimes above the level of its surrounding farm fields.
RiverA river is a natural flowing watercourse, usually a freshwater stream, flowing on the surface or inside caves towards another waterbody at a lower elevation, such as an ocean, sea, bay, lake, wetland, or another river. In some cases, a river flows into the ground or becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to by names such as creek, brook, and rivulet. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities, a stream is defined by its size.
SiltSilt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel when dry, and lacks plasticity when wet. Silt also can be felt by the tongue as granular when placed on the front teeth (even when mixed with clay particles). Silt is a common material, making up 45% of average modern mud.
New OrleansNew Orleans (ˈɔːrl(i)ənz , ɔːrˈliːnz , ˈɔːrlənz ; La Nouvelle-Orléans la nuvɛlɔʁleɑ̃) is a consolidated city-parish located along the Mississippi River in the southeastern region of the U.S. state of Louisiana. With a population of 383,997 according to the 2020 U.S. census, it is the most populous city in Louisiana, third most populous city in the Deep South, and the twelfth-most populous city in the southeastern United States. Serving as a major port, New Orleans is considered an economic and commercial hub for the broader Gulf Coast region of the United States.
Dutch languageDutch (Nederlands ˈneːdərlɑnts), also known as Netherlandic or Netherlandish, is a West Germanic language spoken by about 25 million people as a first language and 5 million as a second language. It is the third most widely spoken Germanic language, after its close relatives German and English. Afrikaans is a separate but somewhat mutually intelligible daughter language spoken, to some degree, by at least 16 million people, mainly in South Africa and Namibia, evolving from the Cape Dutch dialects of Southern Africa.
FortificationA fortification is a military construction designed for the defense of territories in warfare, and is used to establish rule in a region during peacetime. The term is derived from Latin fortis ("strong") and facere ("to make"). From very early history to modern times, defensive walls have often been necessary for cities to survive in an ever-changing world of invasion and conquest. Some settlements in the Indus Valley Civilization were the first small cities to be fortified.
DanubeThe Danube (ˈdæn.juːb ; ) is the second-longest river in Europe, after the Volga in Russia. It flows through much of Central and Southeastern Europe, from the Black Forest into the Black Sea. A large and historically important river, it was once a frontier of the Roman Empire and today connects ten European countries, running through their territories or being a border. Originating in Germany, the Danube flows southeast for , passing through or bordering Austria, Slovakia, Hungary, Croatia, Serbia, Romania, Bulgaria, Moldova, and Ukraine.
SichuanSichuan (sɪtʃˈwɑːn; , sɹ̩̂.ʈʂhwán; ; alternatively romanized as Szechuan or Szechwan) is a province in Southwest China occupying most of the Sichuan Basin and the easternmost part of the Tibetan Plateau between the Jinsha River on the west, the Daba Mountains in the north and the Yungui Plateau to the south. Sichuan's capital city is Chengdu. The population of Sichuan stands at 83 million. Sichuan neighbors Qinghai to the northwest, Gansu to the north, Shaanxi to the northeast, Chongqing to the east, Guizhou to the southeast, Yunnan to the south, and the Tibet Autonomous Region to the west.
Sea level riseBetween 1901 and 2018, the average global sea level rose by , or an average of 1–2 mm per year. This rate accelerated to 4.62 mm/yr for the decade 2013–2022. Climate change due to human activities is the main cause. Between 1993 and 2018, thermal expansion of water accounted for 42% of sea level rise. Melting temperate glaciers accounted for 21%, with Greenland accounting for 15% and Antarctica 8%. Sea level rise lags changes in the Earth's temperature.
WetlandWetlands, or simply a wetland, is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The primary factor that distinguishes wetlands from terrestrial land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique anoxic hydric soils.
SwampA swamp is a forested wetland. Swamps are considered to be transition zones because both land and water play a role in creating this environment. Swamps vary in size and are located all around the world. The water of a swamp may be fresh water, brackish water, or seawater. Freshwater swamps form along large rivers or lakes where they are critically dependent upon rainwater and seasonal flooding to maintain natural water level fluctuations. Saltwater swamps are found along tropical and subtropical coastlines.
RevetmentA revetment in stream restoration, river engineering or coastal engineering is a facing of impact-resistant material (such as stone, concrete, sandbags, or wooden piles) applied to a bank or wall in order to absorb the energy of incoming water and protect it from erosion. River or coastal revetments are usually built to preserve the existing uses of the shoreline and to protect the slope. In military engineering it is a structure formed to secure an area from artillery, bombing, or stored explosives.
Great Wall of ChinaThe Great Wall of China (, literally "ten thousand li long wall") is a series of fortifications that were built across the historical northern borders of ancient Chinese states and Imperial China as protection against various nomadic groups from the Eurasian Steppe. Several walls were built from as early as the 7th century BC, with selective stretches later joined by Qin Shi Huang (220–206 BC), the first emperor of China. Little of the Qin wall remains. Later on, many successive dynasties built and maintained multiple stretches of border walls.
Second Sino-Japanese WarThe Second Sino-Japanese War was a military conflict primarily between the Republic of China and the Empire of Japan from 1937 to 1945, as part of World War II. In China, the war is called the War of Resistance against Japanese Aggression (). This total war between China and the Empire of Japan is often regarded as the beginning of World War II in Asia, although some scholars consider the European War and the Pacific War to be entirely separate, albeit concurrent.