什么是河流的基准面？
What is the base level of a river?
河流基准面是河流下切所能达到的最低侵蚀面，通常以海平面为其终极基准面。局部基准面可以是湖泊或坚硬岩层。基准面下降会加剧下切，上升则促进堆积。
The base level of a river is the lowest erosion surface it can cut down to, with sea level as the ultimate base level. A local base level can be a lake or a resistant rock layer. A falling base level intensifies downcutting, while a rising one promotes deposition.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#基准面 #下切 #海平面
什么是承压水？
What is confined groundwater (artesian water)?
承压水存在于两个不透水层之间的含水层中，承受静水压力，水位可高于含水层顶板。打井穿透顶板后，水可自流涌出，称为自流井。承压水受污染较慢但一旦污染更难恢复。
Confined groundwater sits in an aquifer sandwiched between two impermeable layers and is under hydrostatic pressure, so its level can rise above the aquifer's roof. When a well pierces the cap, water may flow out by itself, an artesian well. It is slow to pollute but harder to recover once contaminated.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#承压水 #自流井 #不透水层
什么是河流袭夺？
What is river capture (stream piracy)?
河流袭夺指一条河流因侵蚀更强，切穿分水岭把另一条河的源头或上游夺为己有的现象。被袭夺河的水量骤减，原河道可能留下风口等遗迹。它是构造与侵蚀共同塑造水系格局的典型过程。
River capture is when one stream, by eroding more vigorously, cuts through a divide and diverts the headwaters or upper course of another river into itself. The captured river loses flow abruptly and may leave relics such as a wind gap. It is a classic process where tectonics and erosion reshape drainage patterns.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#河流袭夺 #分水岭 #水系
什么是蒸腾作用？植物如何把水送回大气？
What is transpiration and how do plants return water to the atmosphere?
蒸腾是植物通过叶片气孔把根部吸收的水分以水汽形式释放到空气中的过程，与蒸发合称蒸散。森林区域的蒸散可显著抬升局地湿度并促进降水。
Transpiration is the release of water vapor through leaf stomata from water a plant has drawn up by its roots; together with evaporation it is called evapotranspiration. In forested regions this flux can markedly raise local humidity and feed precipitation.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#蒸腾 #蒸散 #气孔
什么是地下水补给？
What is groundwater recharge?
地下水补给是地表水通过下渗进入含水层、补充地下水储量的过程。降水、河流渗漏和人工回灌都是重要补给来源。补给速率决定了地下水能否可持续利用。
Groundwater recharge is the process by which surface water infiltrates into aquifers and replenishes stored groundwater. Rainfall, river leakage, and artificial recharge are important sources. The recharge rate determines whether groundwater can be used sustainably.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#补给 #下渗 #含水层
什么是水井和抽水？
What are wells and pumping?
水井是钻入含水层以抽取地下水的竖井，靠水泵把水提到地面。适度取水可由补给维持平衡，但超采会造成地面沉降和水质恶化。许多城市依赖井水作为饮用水源。
A well is a shaft drilled into an aquifer to draw groundwater, using a pump to lift water to the surface. Moderate withdrawal is balanced by recharge, but over-extraction causes land subsidence and worsening water quality. Many cities rely on well water for drinking.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#水井 #抽水 #超采
河流三角洲是怎么形成的？
How does a river delta form?
当河流入海或入湖时，流速骤减，携带的泥沙大量沉积，在河口堆积成扇形或鸟足状地貌即三角洲。泥沙供应充足、波浪和潮汐较弱时三角洲更易发育。著名的如长江三角洲和密西西比河三角洲。
Where a river meets the sea or a lake, its speed drops sharply and the sediment it carries is deposited, building a fan- or bird-foot-shaped landform called a delta. Deltas develop best where sediment supply is ample and waves and tides are weak. Examples include the Yangtze and Mississippi deltas.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#三角洲 #沉积 #河口
什么是径流？
What is runoff?
径流是降水形成、未蒸发也未下渗而沿地表或地下流走的水流，最终汇入河流湖泊和海洋。它可分为地表径流和地下径流。径流的多少决定一个地区的水资源丰歉和洪水风险。
Runoff is the portion of precipitation that neither evaporates nor infiltrates but flows away over or under the ground, eventually reaching rivers, lakes, and the ocean. It is divided into surface runoff and subsurface runoff. Its volume determines a region's water wealth and flood risk.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#径流 #地表径流 #水资源
什么是河流的沉积作用？
What is river deposition?
当河流流速减慢或负载超过搬运能力时，携带的泥沙便会沉积下来。沉积在河口形成三角洲，在弯曲河道凸岸形成点坝。沉积塑造了冲积平原，也埋藏了宝贵的地下水资源。
When a river slows down or its load exceeds transport capacity, the sediment it carries is deposited. Deposition builds deltas at the mouth and point bars on the inside of bends. It shapes alluvial plains and also buries valuable groundwater resources.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#沉积 #泥沙 #冲积平原
尼罗河为什么历史上会定期泛滥？
Why did the Nile historically flood on a regular cycle?
尼罗河的水源主要来自上游埃塞俄比亚高原的夏季降雨，雨水汇入青尼罗河使水位在汛期暴涨。周期性泛滥带来肥沃淤泥，孕育了古埃及农业文明。现代水库修建后这种自然泛滥已被控制。
The Nile's water comes mainly from summer rainfall on the Ethiopian highlands upstream, which swells the Blue Nile and raises the level during flood season. The regular floods deposited fertile silt that sustained ancient Egyptian agriculture. Modern dams have since controlled this natural flooding.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#尼罗河 #泛滥 #汛期
什么是流域（集水区）？
What is a drainage basin (watershed)?
流域是汇集降水并汇入同一条河流及其支流的陆面区域，以分水岭为界。流域内所有的径流最终都流向同一个出口。流域的大小和形状影响洪水过程和人类用水。
A drainage basin is the land area where precipitation collects and flows into a single river and its tributaries, bounded by a divide. All runoff within it eventually reaches the same outlet. The basin's size and shape affect flood behavior and human water use.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#流域 #分水岭 #集水
什么是冰川融水补给？
What is glacier meltwater feeding?
冰川融水补给指河流的水量部分来自高山冰川和积雪的季节性消融。夏季气温升高时融水增多，使河流出现夏汛。这类河流对气候变暖敏感，长期可能面临水量减少。
Glacier meltwater feeding means part of a river's flow comes from the seasonal melting of mountain glaciers and snow. As temperatures rise in summer, meltwater increases and the river peaks. Such rivers are sensitive to warming and may see reduced flow in the long term.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#冰川融水 #夏汛 #补给
大气中的水分驻留时间有多长？为什么这么短？
What is the residence time of water in the atmosphere and why is it so short?
大气中的水汽全球平均驻留时间仅约 8–10 天便通过降水被清除，因为大气含水总量虽小、但循环通量极大。这一短周期使降水对温度与环流变化高度敏感。
Globally, atmospheric water vapor has a mean residence time of only about 8-10 days before it is removed by precipitation, because the total atmospheric store is small relative to a very large cycling flux. This short turnover makes precipitation highly sensitive to temperature and circulation changes.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Trenberth 等（2009）《美国气象学会公报》地球能量收支
Trenberth, K.E. et al. (2009), Earth's Global Energy Budget, Bulletin of the American Meteorological Society
#驻留时间 #水汽 #降水通量
什么是河流的侵蚀作用？
What is river erosion?
河流侵蚀指水流及携带的砂石磨蚀河床和河岸，使其下切和拓宽。下切形成峡谷，侧蚀使河道摆弯。侵蚀强度取决于流量、坡度和泥沙含量。
River erosion is the wearing away of the bed and banks by flowing water and the sediment it carries, cutting down and widening the channel. Downcutting forms canyons, while lateral erosion bends the course. Erosion intensity depends on discharge, slope, and sediment load.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#侵蚀 #下切 #侧蚀
什么是河流的搬运作用？
What is river transportation?
河流搬运指水流把侵蚀下来的泥沙以悬移、推移或溶解等方式向下游输送。搬运能力随流速增大而增强，洪水期能携带大量粗粒物质。搬运和沉积共同塑造了平原与三角洲。
River transportation is the downstream movement of eroded sediment by suspension, bed load, or dissolution. Transport capacity grows with flow velocity, so floods can carry large amounts of coarse material. Together with deposition it shapes plains and deltas.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#搬运 #泥沙 #悬移质
什么是曲流（河曲）？
What is a meander?
曲流是平原河流因侧蚀作用形成的蜿蜒弯道。凹岸受冲刷、凸岸堆积，使弯道不断加宽并可能自然截弯取直。废弃的弯道常留下牛轭湖。
A meander is a sinuous bend formed by lateral erosion on a plain river. The outer bank is scoured while the inner bank builds up, widening the loop until it may be cut off naturally. The abandoned loop often leaves an oxbow lake.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#曲流 #河曲 #牛轭湖
水在大气、河流、冰川和地下分别停留多久？
How long does water stay in the atmosphere, rivers, glaciers, and underground?
水分子在某个库里的平均停留时间叫驻留时间，各库差别极大。大气约9天，河流约数周，土壤约数月到两年，地下水从数年到上万年，冰盖可达数十万年，海洋里最久约三千年。理解这些时间尺度，才能解释为什么污染物会在地下水或冰川里滞留很久。
The average time a water molecule spends in a reservoir is its residence time, and it varies enormously. In the atmosphere it is about 9 days; in rivers, weeks; in soil, months to a couple of years; in groundwater, years to tens of thousands of years; and in ice sheets, up to hundreds of thousands of years. The ocean holds water for roughly 3,000 years. These time scales explain why pollutants linger so long in groundwater and ice.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#水循环 #驻留时间 #水文
海水为什么是咸的?河水流进大海怎么不把海变淡?
Why is the sea salty — why dont rivers dilute it fresh?
河流冲刷岩石时带走了微量的盐分,几亿年来源源不断送进海洋,而水蒸发走了、盐留了下来,越攒越咸。平均每一公斤海水含盐约35克。死海的盐度更高到人都能漂起来。雨水是淡水,因为它在蒸发时把盐留在了海里。
Rivers nibble tiny salt from rocks delivering it to oceans for eons; water evaporates away but salt stays behind, growing saltier — about thirty-five grams per kilogram on average. The Dead Sea is saltier still, floating swimmers easily. Rain is fresh because evaporation leaves salt in the sea.
难度 进阶 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 2 条独立证据
来源 · Source
《十万个为什么》第六版地球分册,少年儿童出版社,2013
Ten Thousand Whys: Earth volume, 6th ed., Juvenile and Children Publishing House, 2013
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-7-5324-9328-9 · 核验依据 2 ISBN 9787532493289
#海水盐度 #蒸发 #水循环
地下水会被污染吗？
Can groundwater be polluted?
会。化肥、农药、污水和工业废液可随下渗进入含水层，使地下水含有害物质。地下水流动缓慢、更新周期长，一旦污染很难治理。保护水源地和合理处理废物是关键。
Yes. Fertilizers, pesticides, sewage, and industrial waste can infiltrate and enter aquifers, contaminating groundwater. Because groundwater moves slowly and renews over long periods, pollution is hard to clean up once it occurs. Protecting recharge areas and managing waste properly are key.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#地下水污染 #下渗 #水源保护
什么是蒸发和蒸腾？
What are evaporation and transpiration?
蒸发是水面和土壤中的液态水变为水汽进入大气的过程。蒸腾是植物通过叶片把体内水分释放到空气中的过程。两者合称蒸散，是水循环中返回大气的主要途径。
Evaporation is the process by which liquid water from surfaces and soil becomes vapor and enters the atmosphere. Transpiration is how plants release water from their leaves into the air. Together called evapotranspiration, they are the main pathway returning water to the atmosphere.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#蒸发 #蒸腾 #蒸散
什么是湿地，它有什么作用？
What are wetlands and what do they do?
湿地是地表常年或季节性积水的过渡地带，如沼泽、滩涂和红树林。它能调蓄洪水、净化水质，并为众多动植物提供栖息地。湿地因此被称为地球之肾。
Wetlands are transitional zones that are flooded year-round or seasonally, such as marshes, mudflats, and mangroves. They store floodwater, purify water quality, and provide habitat for many plants and animals. That is why wetlands are called the kidneys of the Earth.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#湿地 #洪水调蓄 #栖息地
水循环是怎么运作的？
How does the water cycle work?
水循环靠太阳能量驱动，海洋和陆面的水蒸发成水汽进入大气。水汽随气流运动，遇冷凝结成云并降水回到地面。降水流经河流、湖泊和地下，最终又回大海，循环不息。
The water cycle is driven by solar energy: water from oceans and land surfaces evaporates into vapor and enters the atmosphere. The vapor moves with air currents, condenses into clouds, and returns to the surface as precipitation. The water then flows through rivers, lakes, and groundwater before eventually reaching the sea again.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#水循环 #蒸发 #降水
河流的源头一般在哪里？
Where do rivers usually begin?
河流通常发源于山地或高原，源头多为冰川融水、山泉或降水汇集的溪流。水流沿地势向下汇合，逐渐形成更大的河道。源头的水量虽小，却决定了河流的基本性质。
Rivers usually begin in mountains or plateaus, where the source is often glacier melt, springs, or streams fed by rainfall. The water flows downhill and merges to form larger channels. Though small at the source, it sets the river's basic character.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#河源 #山地 #溪流
什么是泉水？
What is a spring?
泉水是地下水在自然出露点涌出地表形成的水流。当地下水位高于地面或遇到断层、不透水层阻挡时，水便从孔隙或裂隙中流出。许多名泉既是水源也具有景观价值。
A spring is groundwater that emerges naturally at the surface. When the water table rises above ground or meets a fault or impermeable layer, water flows out through pores or fractures. Many famous springs serve as water sources and scenic attractions.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#泉水 #出露 #地下水
什么是蒸发？它如何成为水循环的一部分？
What is evaporation and how is it part of the water cycle?
蒸发是太阳加热使江河湖海的水变成水汽升入空气的过程。水汽随后凝结成云、以降水返回地面，再流回水体，构成不断循环的水循环。
Evaporation is the process by which the Sun's heat turns water from rivers, lakes, and oceans into vapor that rises into the air. The vapor later condenses into clouds, falls as precipitation, and flows back to the water bodies, completing the cycling of water.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Tarbuck & Lutgens,《Earth Science》第14版,Pearson,2015
E. J. Tarbuck and F. K. Lutgens, Earth Science, 14th ed., Pearson, 2015
#蒸发 #水循环 #降水
雨水落下来之后,去哪里旅行了?
Where does rainwater travel after it falls?
雨点开始了一场大旅行:有的钻进泥土给树根喝水,有的汇进小溪流向大河奔向大海,有的被太阳晒热变回看不见的水蒸气飞上天,攒够了再变成新的雨点落下来。这场旅行永远不停站!
Raindrops start a grand trip: some sink to give tree roots drinks, some join streams racing rivers to the sea, some evaporate skyward to become new rain later. The journey never stops!
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 2 条独立证据
来源 · Source
《十万个为什么》第六版地球分册,少年儿童出版社,2013
Ten Thousand Whys: Earth volume, 6th ed., Juvenile and Children Publishing House, 2013
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-7-5324-9328-9 · 核验依据 2 ISBN 9787532493289
#水循环 #河流 #蒸发