斯太尔河, 奥地利 Steyr River, Austria (© guenterguni/Getty Images)

斯太尔河, 奥地利 Steyr River, Austria (© guenterguni/Getty Images)

大自然的蓝色奇观 Nature's blue wonder

斯太尔河，奥地利

今天这张照片并未经过调色，奥地利斯太尔河的水真的就是这般湛蓝。斯太尔河流经托特斯山脉，当地植被稀少，那为什么斯太尔河还能如此清澈湛蓝？答案就在环绕斯太尔河谷的群山之中。雨水和融化的雪水流入斯太尔河后，其中较重的沉积物沉到水底，而较细的沉积物则会悬浮在水中。被沉积物散射或反射的阳光就赋予了河水这样鲜艳的蓝色。

Steyr River, Austria

These whitewater rapids are found in Upper Austria, where the Steyr River crashes down from the barren Totes Gebirge (the Dead Mountains) through this verdant landscape. When it comes to the ancient town of Steyr, at the foot of the Alps, it will meet the Enns River, which flows into the Danube.

What gives the Steyr that stunning blue hue? The answer is found in the mountains themselves. When there's rainfall or the surrounding snow melts, eroded sediment flows into the river. Heavier sediment sinks to the bottom and finer sediment stays suspended in the water. Sunlight is scattered or reflected by the sediment, allowing us to see a vibrant shade of blue, as the Steyr crashes through this lush landscape.