1 . U.N. Report Warns Nature Crisis

A new U.N. report focuses on the negative effects of human activity on nature. It says one million plant and animal species on land, in the seas and in the sky are now in danger of extinction.

    1     It draws on the work of 450 scientists from dozens of countries. The Earth has always suffered from human activity, it says. However, these scratches (划伤) have become deep scars (伤疤) over the past 50 years. Species are going extinct several hundred times faster than the average rate during the past ten million years. It’s something that has never happened before in human history.

    2     Since 1970, the human population has doubled. The global economy has grown by four times. To feed, clothe and give energy to this fast-changing world, lots of forests have been cut down. Between 1980 and 2000, one million square kilometers of tropical (热带的) forest were lost. Furthermore, hunting, overfishing and pollution have also been killing species in great numbers.

The problem can be fixed, the report says.     3     The amount of land and sea that is under protection needs to increase rapidly. The report suggests governments move away from using GDP as a key measure of development. Long-term effects must be considered, too.

Professor Eduardo Brondizio of Indiana University is an author of the report. He says, “We all know what needs to be done. The knowledge is there.     4    ”