Seventy-nine percent of China's wetlands are poorly protected and their total coverage is shrinking as well, according to a survey released on Thursday, Feb. 2, also known as World Wetlands Day.

The country's natural wetland reserves have decreased by more than 8,000 square km over the past three decades, with marshes and lakelands reduced the most, according to the survey, which was released by the Institute of Remote Sensing Applications under the Chinese Academy of Sciences.

Poorly-protected wetland areas are mainly located in west and southwest China, some coastal regions, as well as along the Yangtze River.

According to the survey, only 15 percent of the wetlands found along the Songhuajiang River in northeast China's Jilin province are well protected.

The survey called for wetland protection legislation, remote-sensing supervision and strengthened industrial restructuring in areas near the reserves.

China had 614 natural wetland reserves as of 2011, including 91 at the state level.