Home to the headwaters of the Yangtze, Yellow and Lancang rivers, the Sanjiangyuan area on the Qinghai-Tibet Plateau (青藏高原) is known as “China’s water tower.” It is a     1     (whole) unique plateau wetland ecosystem and serves as     2     important ecological defense for the country.

Decades ago, serious environmental degradation (恶化) in Sanjiangyuan,     3     was caused by climate change and human activities, resulted in a large number of lakes drying out and wildlife numbers falling sharply. In 2016, the pilot program for the Sanjiangyuan National Park management system     4     (launch). Through painstaking practice, development and innovation, efforts have been made     5     (turn) the park into a symbol of the progress of China’s ecological civilization.

Over the past years, the ecological environment of the Qinghai-Tibet Plateau     6     (experience) comprehensive changes. Water conservation in the area has risen     7     11 percent every year, compared with 10 years ago.

Local residents enjoy the gifts given by nature, and the     8     (establish) of the national park has enabled them to transform from exploiting (开发) nature to becoming its protectors and benefiting from it. Some work as tour guides,     9     (assist) visitors from home and abroad.

Today, as people walk on the vast land of Sanjiangyuan, looking at the expansive mountains, glaciers, lakes and pastures,     10     catching sight of wild animals and birds, they cannot help be impressed by the vastness and beauty of nature.

Global warming is a gradual increase in the earth’s temperature, generally due to the greenhouse effect    1    (cause) by increased levels of carbon dioxide and other pollutants.

Temperatures and sea levels are rising, possibly contributing    2    more storms. The rising has influenced a lot,     3    (result)in a lot of climate problems, and humans are at least partially    4    (blame). Global warming causes climate change,    5    places a serious threat to life on the earth in    6    (vary) forms like widespread flooding and extreme weather. Climate experts    7    (gather) detailed observations of different weather    8    (phenomenon) since the mid-20th and of related influences on climate. Scientists have high confidence    9     global temperatures will continue to rise for decades to come,    10    (large)due to greenhouse gases produced by human activities.