The most effective way     1    (fight) global warming is to plant lots of trees, a study has said. And there is enough space for new trees to cover 3.5 million square miles, Swiss     2    (scientist) reported in Science. That area is roughly the size     3    the United States.

The study calculated that over the decades, those new trees could suck up nearly 830 billion tons of heat-trapping carbon dioxide (CO2) from the atmosphere. That’s about as much carbon pollution     4    humans have caused in the past 25 years.

Six nations with the most room for new trees     5    (be) Russia, the United States, Canada, Australia, Brazil and China.

Study co-author Thomas Crowther     6    (figure) that there were other more effective ways besides     7    (cut) emissions ( 排放物 ), such as people switching from meat-eating to vegetarianism. But, he said, tree planting was by far the cheapest climate change solution.

Thomas Lovejoy, a George Mason University conservation biologist, called it “a good news story” because planting trees would also help promote the     8    (protect) of biodiversity.

“It is not easy or realistic to think the world will suddenly start planting trees everywhere, although many groups have started,” Crowther said. “It’s     9    (certain) a monumental challenge,     10     is exactly what people are saying about the problem of climate change.”

This year, August 15th marked China’s first National Ecology Day,     1     aims were to raise awareness of environmental protection and address unlawful activities and safeguard the development of forestry and grassland resource by law.

The establishment of National Ecology Day will enhance ecological understanding among the public and help the nation     2    (well) participate in global environment and climate governance.

The move     3    (see) as part of China’s efforts to build an ecological civilization, a concept that glorifies balanced and sustainable development and harmonious coexistence between     4    (human) and nature     5     promotes the building of a community with a shared future for mankind.

China’s laws and administrative regulations     6    (involve) the environment and ecology,     7    (base) on what environmental difficulties villagers are eager to solve and what ecological measures should be taken urgently from their opinions, have laid a solid legislative (立法的) foundation     8     the ecological civilization.

    9     makes Aug. 15 special is that on that day in 2005, the concept of “lucid waters and lush mountains” was first put forward, being     10    (value) assets.