河流

The region in the altitude f rom 4400 to 4600 meters , which is mainly covered by alpine meadow and alpine swamp meadow , is st rongly degraded by the stock raising with it s influence radius of about 24 kilometers. The influence distance perpendicular to roads is also 24 kilometers , since road const ruction accelerates human2induced destruction to vegetation. Vegetation in shade aspect is rising due to the increase in precipitation , while vegetation in sunny aspect tends to be stable or degraded because of the enhancement in sunlight . Furthermore , the vegetation coverage is influenced by the groundwater level . In near riverbed fields , where the depth of groundwater is shallow , plant s can easily grow ; while in far riverbed fields , vegetation is prone to degrade due to drainage. The radius of river influence is 24 kilometers.

海拔4400～4600m的较低海拔地带退化最强烈，主要为高寒草甸与高寒沼泽草甸受牧业影响较大；牧业影响半径为24km；道路的影响范围为24km，道路的修建加速了人类对高原植被的破坏作用；阳坡植被呈现趋于稳定和退化的趋势，阴坡植被表现为增长的趋势，降水量增加是源区植被，尤其是阴坡植被变好的重要原因，而太阳光照增强是导致阳坡干旱和植被趋于退化的潜在原因；近河床区地下水位埋深较浅，植被生长具有稳定的地下水源；在远离河床的一定区域内，地下水易于疏干，植被易于退化，河流影响范围为24km。

Late he became a river boat pilot.

Late他成为一条河流船pilot。

The Piranha is a freshwater fish living in South American rivers.

水虎鱼是淡水鱼，生活在南美的河流中。

We set off down the river to penetrate the jungle. The pirogue moves fast through the thicket of the forest.

我们通过河流穿过丛林，独木舟从森林最茂密的地方疾驰而过。

Numerical simulation results show that the typical features of primary flow, secondary flow and velocity redistribution in natural river bends are closely related to the special planform and flow depth conditions of natural river meanders. The lateral redistribution of flow is significant when water depth is small. The main stream approaches the concave bank upstream the bend vertex when river width is small.

数值试验结果表明，自然河流河弯中的主流、二次环流和流速重分布特征是与自然河弯的特殊几何形态特征、水深条件紧密相连的，水深越小则流速沿横向的重分布越为显著；河宽越小则水流动力轴线在凹岸的顶冲点越为提前。

A South American river; tributary of Rio de la Plata.

南美洲的一条河流；拉普拉塔河的支流。

The platypus is found in lakes, streams and rivers of eastern Australia.

鸭嘴兽出没于澳大利亚东部的河流，湖泊和水流中。

And the Tibetan Plateau is essentially the source point of all of Asia's major rivers.

而且青藏高原也是所有亚洲主要河流的发源地。

New housing projects and factories will go up, and they will pollute the river.

新的房屋和工厂会建立起来，他们会污染河流。

I think we can save the use of water .we can stop polluting the air and rivers .

我想，我们能节约用水，我们能停止污染空气和河流。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。