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China’s efforts to fight desertification in its northern area     1     (achieve) remarkable progress over the past 45 years. So far, the Three-North Shelter Forest Program     2     (launch) in 1978 has planted and conserved 32 million hectares (公顷) of forests and restored 85 million hectares of degraded grassland, and the forest     3     (cover) in the project area has increased from 5.05 percent in 1978 to 13.84 percent today.

The project has set up a green Great Wall to act as a safeguard     4     sandstorms, conserve soil and water and promote agricultural development in the northern border of China. Though extraordinary achievements are made in the program, the work     5     (say) to be still challenging due to the wide distribution and severe conditions of desert land. The environmental delicacy of the region and continuous environmental issues make the task even     6     (hard).

Recognizing the importance of desert ecosystems in regulating climate and keeping     7     balanced environment, the authorities shifted from a traditional approach to working in harmony with it,     8     (allow) for sustainable development and coexistence. Bringing nature to     9     (it) original condition should not rely on human efforts in the long term. The scientific and holistic (全面的) approach to conserving mountains, rivers, forests and farmland is crucial,     10     the ecologists believe can help nature restore itself.

Human voices cause much more fear in wild animals than the sound of lions, a study in South Africa has found. Scientists played recordings of people talking     1     (normal) through speakers in the Kruger National Park. About 95% of the animals     2     (be) extremely frightened and quickly ran away. In contrast, recordings of snarling and growling lions caused obviously     3     (little) alarm. During the experiment, they noted, that some elephants, in response to the big cat calls, even attempted     4     (face) the source of the sound.

According to the study, the animals have learnt that contact with humans is extremely     5     (danger) . The fear exhibited goes beyond the Kruger National Park, as a global pattern shows wildlife tend to fear humans more than any other predator (捕食者). The authors note that this creates a challenge for areas,     6     rely on wildlife tourism, because the human visitors they want to attract are unintentionally scaring off the animals they have come to see.     7    , the findings open up the possibility to protect weak species. Human sounds, when     8     (use) properly, could help protect against illegal hunting. “Now we     9     (work) together in experiments, testing whether we can prevent rhinos     10     hunting hotspots,” one of the authors said.