152. What natural resource that is disappearing needs to be saved?

The world's resources are incredibly important, and as the world's population grows higher and faster, it is difficult to hold on to these precious assets. While all resources have their own important uses, I believe that forests are the resource that we should be most concerned about preserving.

Trees provide three important functions in the ecosystem. First, they transpire water into the air, creating clouds, and therefore, rain. Without trees, this cycle is interrupted, and rainfall is drastically reduced to minimal levels. Second, trees hold topsoil in place and soften the impact of water on the ground. This is of utmost importance in rain forests, where decomposition is rapid and because of this, the layer of topsoil might only be five to ten centimeters deep. Finally, trees are important to the ecosystem because they protect streams from debris and silt. If the trees were all removed, there would be nothing holding back this dirt from our rivers, destroying the aquatic environment.

Trees also, of course, provide natural beauty to a country. This is very important for tourism, as many visitors enjoy going on long hikes through wooded areas, and taking in the beautiful scenery. If a country has no natural beauty, there will be little draw for tourists to come and visit. While cities can be exciting, most people are drawn to these natural jewels.

Forested area is also the main habitat for a plethora of animal species. In fact, most of the extinction and endangerment of animals today can be attributed to habitat destruction. If we continue our trend in deforesting the world, we will soon find ourselves living in a barren wasteland, with no wildlife to keep us company. The effects of the extinction of even one species of animal is yet unknown. Breaking the food chain on even one level might have profound ripples through all life on earth.

译文

152. 哪种正在消失的自然资源需要保护?

世界上的各种资源都非常重要，而且随着世界人口的快速增长，要想保存这些珍贵的资源非常困难。虽然所有的资源都有各自不同的重要用途，我认为森林是我们最应该注意保护的资源。

树木对生态系统提供了三种重要的功能。首先，它们把水分蒸发到空气中形成了云，因此才会形成降雨。没有树木，这个循环就会被打断，而降水量也会急剧降低到最低水平。其次，树木能够保持地表土并且减轻雨水对土地的撞击。这在热带雨林中是极其重要的，那里的腐烂分解很迅速，因此地表土层可能只有5~10厘米厚。最后，树木对生态系统很重要还因为它们防止了碎石和泥沙对河流的破坏。如果把树木全部移走，那么就没有什么能够防止碎石进入我们的河流，破坏水生环境。

当然，树木还能给一个国家提供自然美景。这对旅游业非常重要，因为很多旅行者喜欢在树林中远足并融入优美的景色之中。如果一个国家没有自然美景，那么对旅游者前来游览就没有多少吸引力。尽管城市可能会令人兴奋，但大多数人更会被这些自然美景吸引。

森林也是众多动物的主要栖息地。实际上，现在绝大多数动物品种的灭绝和濒临灭绝都是因为栖息地被破坏。如果人类继续砍伐森林，我们很快就会发现自己居住在一片荒芜的废墟上，身边没有任何野生动植物的陪伴。虽然现在还不知道每灭绝一种动物会产生什么样的后果，但是哪怕在一个环节上打破食物链，都有可能对地球上的全部生命产生深远的影响。

Word List

• assets ［ˈæsets］ n. 资源
• debris ［dəˈbri:］ n. 碎石
• ecosystem ［ˈekəuˌsistəm］ n. 生态系统
• silt ［silt］ n. 泥沙
• transpire ［trænsˈpaiə］ v. 蒸发
• aquatic ［əˈkwætik］ adj. 水的；水生的
• interrupted ［ˌintəˈrʌptid］ adj. 被中断的
• hike ［haik］ n. 远足
• drastically ［ˈdræstikəli］ adv. 激烈的
• plethora ［ˈpleθərə］ n. 过多；过剩
• topsoil ［ˈta:pˌsɔil］ n. 地表土
• attribute ［əˈtribju:t］ v. 归因于
• decomposition ［di:ˌka:mpəˈziʃən］ n. 分解；腐烂
• barren ［ˈbærən］ adj. 荒芜的
• ripple ［ˈripəl］ n. 波动；起伏