Ocean-related industries expanded at a faster pace than the overall economy last year, and the country's expansive maritime area has become an alternative source of energy, food and fresh water, an official said.

The Ministry of Natural Resources said on Wednesday that the value of the ocean economy — an umbrella term covering sectors ranging from shipbuilding to ocean fish farming and freight services — topped 9.9 trillion yuan ($1.37 trillion) last year, up 6 percent year-on-year.

That was higher than the 5.2 percent growth rate of China's overall economy last year.

The share of ocean-themed sectors in the national economy also inched up one-tenth of a percentage point to 7.9 percent of GDP.

"The ocean economy has rebounded fiercely and has helped the national economy recover," said Cui Xiaojian, deputy director of the National Marine Data Information Center, an affiliate of the ministry's State Oceanic Administration.

He said the amount of marine-derived crude oil extracted grew 5.8 percent year-on-year, while natural gas extractions increased 5.8 percent due to breakthroughs in marine oilfield exploration and have become a major contributor to China's increased energy yield in recent years.

Ocean-based wind power plants produced 17 percent more electricity than in 2022, serving as powerful support for the nation's energy generation, Cui said.

He said the rapid expansion of deep-sea fish farming has bolstered the supply of quality seafood, whose yield rose nearly 3 percent from 2022 to about 35 million metric tons last year.

Desalination projects are being constructed in coastal regions, including Tianjin and the provinces of Shandong and Zhejiang, with a combined capacity of 300,000 tons of seawater each day, he added.

The expansion of the ocean economy, especially deep-sea aquaculture, follows China's plan to step up its national food security efforts by diversifying its food sources.

In 2017, central authorities attending the nation's annual rural work conference urged officials to develop a "macro food perspective "and seek food supplies from unconventional areas of agriculture. As a result, grassland, forests, the ocean and even microorganisms have been listed as potential food sources to meet the country's growing needs for nutritious sustainment.

The push to develop a "macro food perspective" and diversify the country's food sources was reiterated at the most recent rural work conference in December.

China has, in recent years, also phased out offshore aquatic farms that clog up shipping lanes and damage the health of mangroves, while simultaneously coming up with more deep-sea alternatives as the country looks to its expansive territorial waters for food supplies.

Meanwhile, the use of fish feed and antibiotics at enclosed farms dotting the coastline have long been blamed for pollution.

Authorities called last year for the rapid expansion of cage farming farther from the shoreline, with the help of box-shaped facilities that can feed and monitor fish populations remotely. It encouraged the manufacture and use of cages and fishing vessels that can be shuttled around to keep farms running.