Clear explanation of why the leaves turn brown through the winter period.

There are a number of reasons why the leaves turn brown in winter.

The earth further away from the sun in winter, the earth spins in a egg shape, the bottom of the egg is nearest to the sun which is summer. For plants to make food it has to go through a process called photosynthesis. Photo means light and synthesis means energy. The plants absorb light using their leaves, because the sun is far away there are less light beams for the leaves to absorb. Light on its own cannot make the plant grow it also needs water which only can be absorbed by the roots underfround.

What happens to the water?

Because the sun is further away, not enough heat is distrubuted into the earth, so all the water gets frozen and cannot be sucked in by the roots.

关于在冬季，叶子为什么变黄的清楚解答。

冬季里叶子为什么变黄有许多的原因。冬天的地球离太阳很远。

地球（围绕太阳）旋转的轨道是卵形的，在卵形轨道的底部，地球距离太阳最近，这时季节就是夏天。植物要通过一个叫做光合作用PHOTOSYNTHESIS的过程来制造食物。PHOTO的意思就是光，SYNTHESIS的意思是能量（聚合）。植物通过叶子来吸收光能。因为（在冬天）太阳离地球越来越遥远，叶子可以吸收的光越来越少。植物生长不仅依赖光，还需要水分。植物通过地下的根来吸收水分。

那么水怎么了呢？

因为太阳离地球太远，给与地球的热量不够多，所以地上的水结了冰，根就不能吸收水分了。