050 层林尽染

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Welcome to my forest. It is autumn, so it is very wonderful here

欢迎来到我的森林。现在是秋天，所以这里非常美妙。

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All the animals, including squirrels like me, are busy getting ready for winter

所有的动物，包括像我这样的松鼠，都在忙着为冬天做准备。

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Look around you and you will see that the leaves on the trees have changed colors

看看你的周围，你会看到树上的叶子已经变了颜色。

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The maple trees have turned bright red, and the elm trees have turned brown and yellow

枫树变成了鲜红色，榆树变成了棕色和黄色。

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Have you ever wondered why the green leaves change into so many different colors?

你有没有想过，为什么绿叶会变成这么多不同的颜色？

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Well, in the spring and summer when the leaves are fresh, they are filled with something called chlorophyll

其实，在春天和夏天叶子新鲜的时候，它们充满了一种叫做叶绿素的东西。

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Chlorophyll is the natural coloring in the leaves that makes them green

叶绿素是叶子中的天然色素，使它们呈现绿色。

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In order to make food, trees need energy from the sun

为了制造食物，树木需要来自太阳的能量。

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Chlorophyll collects the energy from the sun and stores it in the leaves

叶绿素收集太阳的能量，并将其储存在叶子中。

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The leaves use this energy to make a liquid sugar, called sap, that the trees use for food

叶子利用这些能量制造一种叫做树液的液态糖，树木用它作为食物。

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The trees spend the spring and summer producing food so that they can grow bigger

树木在春季和夏季制造养分，好让自己长得更大。

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During the summer months, the trees get taller and wider and they grow more branches and roots

在夏季的几个月里，树木变得更高更粗，长出更多的枝叶和根系。

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But most importantly, the trees use their energy to grow nuts and fruits for animals like me to eat

但最重要的是，树木用它们的能量结出坚果和水果，供像我这样的动物食用。

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At the end of the summer, things begin to change

夏末时分，情况开始发生变化。

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It becomes cooler, and there is much less sunlight during the day

天气变得更凉爽，白天的日照也大大减少。

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Chlorophyll needs the sunlight and cannot survive in the cold weather

叶绿素需要阳光，在寒冷的天气里无法存活。

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So in the autumn when the weather becomes cool, the trees can no longer make chlorophyll

所以，到了秋天，天气变凉时，树木就无法再制造叶绿素了。

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When this happens, the leaves lose their green color

当这种情况发生时，树叶就失去了它们的绿色。

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When the green chlorophyll disappears, the leaves' other colors can be seen

当绿色的叶绿素消失后，叶子的其他颜色就显现出来了。

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Trees like elm, birch, and poplar show their yellow and light orange colors

像榆树、桦树和杨树这样的树木，会展现出黄色和浅橙色。

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These colors were in the leaves all summer, but because of the green chlorophyll, we could not see them

这些颜色整个夏天都在叶子里，但因为绿色叶绿素的存在，我们看不到它们。

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Some trees, however, get new bright colors in the fall

不过，有些树在秋天会获得新的鲜艳色彩。

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For example, maple trees turn bright red, and sumac trees turn dark red

例如，枫树会变成鲜红色，盐肤木会变成暗红色。

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These trees get their color from red pigments that build up in the leaves when the sap stops flowing in the fall

这些树的颜色来自秋天树液停止流动时，在叶子里积累的红色素。

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These pigments turn leaves red, pink, and even purple

这些色素把叶子变成红色、粉色，甚至紫色。

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This natural coloring occurs in trees and other plants

这种天然着色发生在树木和其他植物身上。

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It gives some vegetables, like beets and radishes, their red color

它让一些蔬菜，如甜菜和萝卜，呈现出红色。

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It is also what makes some flower blossoms red and pink

有些花朵之所以是红色和粉色，也是因为这个原因。

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The red pigments come into the leaves during cool, dry, sunny days

在凉爽、干燥、阳光充足的日子里，红色素会进入叶子。

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I love to go running through the trees, looking at all the colors

我喜欢在树林间奔跑，欣赏所有的色彩。

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Even on the same tree, not all the leaves have the same color

即使是同一棵树，也不是所有的叶子颜色都一样。

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On some trees, the top leaves are bright red, but the bottom leaves are almost yellow

有些树上，顶部的叶子是鲜红色，但底部的叶子几乎是黄色的。

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This is because the top ones get more sun

这是因为顶部的叶子能得到更多阳光。

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On trees near a river, the leaves are not bright because trees that get lots of water do not usually have colorful leaves in the fall

在河流附近的树上，叶子不鲜艳，因为有充足水分的树通常在秋天不会有五彩斑斓的叶子。

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But way up there on the top of a mountain, the leaves get lots of sun and little water, so they are very colorful

但在高高的山顶上，叶子能得到很多阳光和很少水分，所以它们色彩非常鲜艳。

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Even from year to year, the colors of the leaves change

甚至每年之间，叶子的颜色也会发生变化。

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When autumn is dry and cool, the leaves will have brilliant, shining colors

当秋天干燥而凉爽时，叶子会呈现出绚丽闪耀的色彩。

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But when the autumn is cloudy and wet, the leaves will not be as beautiful

但当秋天多云且潮湿时，叶子就不会那么美了。

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The autumn leaves are beautiful to look at, but they don't last very long

秋叶看起来很美，但不会持续很久。

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Without chlorophyll, the leaves cannot live. Soon the leaves must fall off the branches onto the ground

没有叶绿素，叶子就无法存活。很快，叶子就必须从树枝上掉落到地上。

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But this is good for squirrels because we love to play and jump in them

但这对松鼠来说是好事，因为我们喜欢在里面玩耍跳跃。

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When all the leaves have fallen from the trees, the animals know that winter is coming

当所有的叶子都从树上落下时，动物们就知道冬天要来了。

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We hurry up and pack away all our food, and then we tuck ourselves in our little houses and go to sleep for the winter

我们赶紧收拾好所有的食物，然后蜷缩在小房子里，准备睡过整个冬天。

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The trees also sleep during the winter

树木在冬天也会休眠。

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Eventually the leaves that fall from the trees decay and turn into soil that is used during the following years as fertilizer for the trees

最终，从树上落下的叶子会腐烂，变成土壤，在之后几年用作树木的肥料。

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You see, one of the beautiful things about nature is that everything works in a cycle

你看，大自然的一个美妙之处就在于，一切都在循环中运转。

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The trees wake up in the spring with fresh new leaves

树木在春天醒来，长出鲜嫩的新叶。

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These leaves grow in the summer, fall in the autumn, and then are turned back into soil so that more leaves can grow the next spring

这些叶子在夏天生长，在秋天掉落，然后又变成土壤，好让更多叶子能在来年春天生长。

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With the help of chlorophyll, the trees get bigger and stronger every year

借助叶绿素，树木每年都变得更大更强壮。