An aerial view of Yantai's Changdao. [Photo/VCG]

Following its December 2023 approval, the "Blue Granary" Marine Economic Development Zone in Changdao, Yantai — Shandong's first offshore economic zone — has pioneered a new model for marine space development.

Inspired by land-based industrial parks, it introduced "standard sea" areas with pre-surveyed waters equipped with permits and infrastructure, allowing companies to start production immediately. A 5,000-mu (333.33 hectares) demonstration area now generates 28 million yuan ($4.07 million) annually, which is 40 percent higher than traditional methods.

The zone is building a complete industry value chain around deep-sea aquaculture. In June 2024, it initiated a new salmon farming model: young salmon raised in inland hatcheries are then transferred to deep-sea cages off Changdao. Upstream, cross-regional breeding bases supply high-quality fingerlings. Downstream, an offshore processing park produces smoked salmon for European markets.

To address high investment costs, the zone diversified financing through government funds and green bonds — including a "seagrass carbon sink loan" that facilitated reef construction. A "flyaway" industrial park in Yantai attracts 35 leading firms, enabling offshore R&D and island production. The natural coastline has surged to 87.7 percent, and Daheishan Island became China's first "carbon-negative island".

A management committee only handles industry and investment, supported by a 1-billion-yuan fund and a listed "chain leader" driving mergers. This framework offers a replicable model for China's marine economy — transforming ocean ranches into engines of rural vitalization.