神奇校车带领孩子们进入浩瀚的科学领域,游梭于生物科学、地球科学、太空科学、气象学、古生物学等各门学科中。被纽约时报评为最新鲜有趣、最富有创意和想象力的科学启蒙方式。孩子

发表于:2018-12-31 / 阅读(41) / 评论(0) 分类 神奇校车系列丛书

神奇校车带领孩子们进入浩瀚的科学领域,游梭于生物科学、地球科学、太空科学、气象学、古生物学等各门学科中。被纽约时报评为最新鲜有趣、最富有创意和想象力的科学启蒙方式。孩子

发表于:2018-12-31 / 阅读(60) / 评论(0) 分类 神奇校车系列丛书

神奇校车带领孩子们进入浩瀚的科学领域,游梭于生物科学、地球科学、太空科学、气象学、古生物学等各门学科中。被纽约时报评为最新鲜有趣、最富有创意和想象力的科学启蒙方式。孩子

发表于:2018-12-31 / 阅读(120) / 评论(0) 分类 神奇校车系列丛书

神奇校车带领孩子们进入浩瀚的科学领域,游梭于生物科学、地球科学、太空科学、气象学、古生物学等各门学科中。被纽约时报评为最新鲜有趣、最富有创意和想象力的科学启蒙方式。孩子

发表于:2018-12-31 / 阅读(130) / 评论(0) 分类 神奇校车系列丛书

神奇校车带领孩子们进入浩瀚的科学领域,游梭于生物科学、地球科学、太空科学、气象学、古生物学等各门学科中。被纽约时报评为最新鲜有趣、最富有创意和想象力的科学启蒙方式。孩子

发表于:2018-12-31 / 阅读(137) / 评论(0) 分类 神奇校车系列丛书

society, that first brought civilization to the desert. Far from just scraping by in this harsh landscape, the Garamantes were flourishing. They grew crops, such as cereals and grapes. They kept horses and pigs. Clearly, they needed large amounts of

发表于:2019-01-22 / 阅读(65) / 评论(0) 分类 自然百科2010年

So the rigid hierarchical structure of Egyptian society wasn't just dictated by the Pharaohs. It also emerged because the Egyptians had only one water source - the Nile. 5,000 years ago, it wasn't just the ancient Egyptians who noticed the value of r

发表于:2019-01-22 / 阅读(54) / 评论(0) 分类 自然百科2010年

It worked because the water of the river carried something special within it, an almost invisible treasure that was the secret of Egypts economic might. What made Egypt great is this stuff - silt. It's a rich supermineral silt, it's like an expresso,

发表于:2019-01-22 / 阅读(73) / 评论(0) 分类 自然百科2010年

What that circulation means to us human is that water is a moving target. We constantly have to seek it out in this endless cycle and intercept it wherever and whenever we can. This quest depend on water has played a defining role in human history. T

发表于:2019-01-22 / 阅读(61) / 评论(0) 分类 自然百科2010年

Let's look first. The fresh water that we depend on begins its life in the oceans. As the sun's rays beat down on the surface of the sea, they heat the water molecules until some evaporate. It's the start of an extraordinary journey. Here with water

发表于:2019-01-22 / 阅读(54) / 评论(0) 分类 自然百科2010年

Out there is a river valley that's been carved into the rock. It's been carved by running water, just flew down here smoothly off this rock bed and then cascaded down to the valley north there. Six thousand years ago, that was a big river. Satellite

发表于:2019-01-22 / 阅读(60) / 评论(0) 分类 自然百科2010年

The center of the Sahara Desert in North Africa, one of the driest places on earth. I'm over six hours drive from civilization. Temperatures here regularly reach 100 degrees Fahrenheit, but there's less than half an inch of rainfall each year. Ah,the

发表于:2019-01-22 / 阅读(61) / 评论(0) 分类 自然百科2010年

Of all our planet's forces, perhaps none has greater power over us than water. For me, water is the most magical force on earth. The presence of water shapes, renews and nourishes our planet. Oh, my God ! You get all wet there! It's our planet's life

发表于:2019-01-22 / 阅读(58) / 评论(0) 分类 自然百科2010年

Today we take our control of water for granted. Modern civilization couldn't exist without it. But there is still only a finite amount of water to go around. In many parts of the world, scarcity has led to a bitter struggle for control over the avail

发表于:2019-01-22 / 阅读(58) / 评论(0) 分类 自然百科2010年

But as it grew, the Khmer Kingdom faced the stumbling block. When the monsoon finished each year, the fish and water would vanish. So each year, the inhabitants were plunged into drought and hunger. The Khmer rules off the challenge magnificently. Th

发表于:2019-01-22 / 阅读(77) / 评论(0) 分类 自然百科2010年

And this was their greatest achievement: the legendary temple complex of Angkor. You know, a real sense of age of this place here. This was built over 1,200 years ago. At a few places right here you can see a show of the age that faces are all worn,

发表于:2019-01-22 / 阅读(66) / 评论(0) 分类 自然百科2010年

It's just magic. When you follow it, you can see that this is the perfect union of the tree and the villages. The locals have kind of trained the roots, kind of guided them through and netted them together. What they've done here is they've grabbed s

发表于:2019-01-22 / 阅读(76) / 评论(0) 分类 自然百科2010年

The key was adaptation. Rain. A familiar occurrence in many parts of the world. But this is rain at its most extreme, the monsoon. The significance of the monsoon isn't the human discomfort, but how the people here have learned to live with it. I'm t

发表于:2019-01-22 / 阅读(72) / 评论(0) 分类 自然百科2010年

But the human's struggle to pin down water is forever balanced on a knife edge. Get that balance wrong, and you pay the price. For all their ingenuity, the Garamantes over-exploited their ground water. Eventually, it ran out, and so did their civiliz

发表于:2019-01-22 / 阅读(75) / 评论(0) 分类 自然百科2010年

They could not lose. Resistance movements started. They would take over places like this and opened the sluice gate allowing the water to pour back down into Owens Valley. Irregularly they dynamited the aqueduct. But the city rebuilt it and the game

发表于:2019-01-22 / 阅读(82) / 评论(0) 分类 自然百科2010年