India and China are leading the global greening effort, a latest NASA study said on Monday, observing that the world is a greener place than it was 20 years ago.
Data from NASA Earth satellites show that human activities in China and India play an important part in this greening of the planet, thanks to tree planting and agriculture. The effect comes mostly from tree-planting programs in China and agriculture in both countries. “China and India account for one-third of the greening,’’ said lead author Chi Chen of Boston University.
China alone accounts for 25 percent of the global increase in leaf area with only 6.6 percent of global green area. The greening in China is from forests and croplands (农田), but in India, it is mostly from croplands with minor contribution from forests. China’s huge contribution to the global greening trend comes in large part from its programs to protect and expand forests.
“When the greening of the earth was first observed, we thought it was due to a warmer, wetter climate from the added carbon dioxide (CO2) in the atmosphere. Now with the data, we see that humans are also contributing,” said Rama Nemani, research scientist at NASA. “Once people realize there is a problem, they tend to fix it. In the 1970s and 80s in India and China, the situation around vegetation (植被) loss was not good. In the 1990s, people realized it, and today things have improved. That’s what we see in the satellite data,” added Nemani.
Land area used to grow crops is comparable in China and India, and has not changed much since the early 2000s. Yet these places have greatly increased both their green leaf area and their food production by enhancing the way of cropping. This was achieved through multiple cropping practices, where a field is replanted to produce another harvest several times a year. Production of grains, vegetables, fruits and more has increased by about 35%〜40% since 2000 to feed their large populations.
【小题1】In India, the greening mainly comes from .| A．agriculture. | B．tree planting. | C．forests and croplands. | D．a warmer and wetter climate. |
| A．Carbon dioxide causes global warming. |
| B．Man can actively change the environment. |
| C．In India and China, vegetation loss has been solved. |
| D．Climate has little to do with the greening of the earth. |
| A．Praising. | B．Ignoring. | C．Improving. | D．Limiting. |
| A．India and China lead the global greening. |
| B．Human activities change the global climate. |
| C．Warmer climate contributes to the global greening. |
| D．Land area for crops in China and India has changed much. |
