BEIJING, Feb. 25 -- China's forest areas covered 21.63 percent of the country's land as of the end of 2013, a rise of 1.27 percentage points compared to five years ago, a State Forestry Administration (SFA) survey showed.

Total forest areas grew to 208 million hectares by the end of 2013, up from 195 million ha five years ago. Growing stock per hectare increased by 3.91 cubic meters to 89.79 cubic meters over the past half a decade, according to report of the five-year survey released on Tuesday.

Growing stock is a term that measures the volume of existing wood resources.

During the period, natural forests expanded by 2.15 million ha to 121.84 million ha.

Planted forests grew by 7.64 million ha to 69.33 million ha, the survey showed. This fast expansion means China has the world's largest growing area for planted forests.

However, SFA chief Zhao Shucong said the country's forest coverage ratio remains far below the global average of 31 percent.

China aims to increase its forest coverage ratio to 23 percent by 2020, but green efforts are being challenged by farming, industrialization and urbanization, Zhao said at a press conference.

In his official notes on the survey, Chinese President Xi Jinping said that despite achievements, China remains short of forests and is weak on ecological defense. Xi said the country will deepen forestry reforms and use innovative methods to grow and preserve forests.

Zhao said that forestry authorities will set strict rules in the supervision and management of forests. Meanwhile, illegal use of forests or violations will be dealt with by the law.