1 . When it comes to cooling the planet, forests have more than one trick upon their trees. A new study finds tropical (热带的) forests help cool the average global temperature by more than 1℃. “The effect is largely from forests’ ability to stockpile CO₂. But around one third of that tropical cooling effect comes from several other processes, such as the letting-out of water vapor (水蒸气),” researchers reported on March 24 in Frontiers in Forests and Global Change.

“We tend to focus on CO₂ and other greenhouse gases, but forests can not only keep CO₂,” said Deborah Lawrence, an environmental scientist at the University of Virginia. “It’s time to think about what else forests are doing for us besides keeping CO₂.”

“Researchers already know that forests influence their local climates through various chemical processes. Trees let out water vapor through their leaves and, like human sweating, this cools the trees and the things around them. But on a global scale, it isn’t clear how the other cooling works compared with the cooling provided by forests’ ability of keeping CO₂,” Lawrence said.

So she and her colleagues studied how over-cutting would affect global temperatures, using data gathered from other studies. For example, the researchers used data to decide how much the letting-out of CO2 stored by those forests would warm the global temperature. They then compared those results with other studies’ results of how much the loss of other aspects of forests.

The researchers found that in forests at latitudes (纬度) from around 50°S of the equator to 50°N, the primary way that forests influenced the global average temperature was through CO₂ store. But other cooling factors still played large roles.

1. What does the underlined word “stockpile” in paragraph 1 mean?

A．Improve.

B．Explore.

C．Store.

D．Defend.

2. What can we learn from Lawrence’s words?

A．Forests need CO2 to keep their balance.	B．Some chemicals are harmful to forests.
C．Forests can sweat and breathe like humans.	D．Forests may benefit us in many other ways.

3. What does paragraph 4 mainly tell us?

A．The result of Lawrence’s research.

B．Lawrence’s research method.

C．The difficulty that Lawrence was faced with.

D．The reason why Lawrence studied trees.

4. In which section of a newspaper can the text be found?

A．Nature.

B．Technology.

C．Culture.

D．Sports.