Marine Economy-Driven Conversion of Old and New Growth Drivers: The Development Foundations, Transformation Characteristics, Current Conditions, and Major Problems of SMEs in Yantai

Against the backdrop of the continued transformation from old to new growth drivers at the regional level, the marine economy has become an important force for coastal cities seeking to restructure their industrial systems, cultivate new engines of growth, and enhance the level of openness. As an important coastal open city on the Shandong Peninsula, Yantai possesses both a solid accumulation of traditional marine industries and a relatively clear layout of emerging marine sectors such as marine engineering equipment, marine biomedicine, seawater desalination, modern port shipping, and marine ranching. At the same time, small and medium-sized enterprises (SMEs) in Yantai are large in number, broad in industrial coverage, strongly private in ownership structure, and increasingly active in technological innovation, industrial coordination, and market expansion. Based on public statistical communiqués, marine economic plans, and policy documents of Yantai, and informed by the literature on the marine economy, SME transformation, and regional industrial upgrading, this paper examines the development foundations, transformation characteristics, current conditions, and major problems of SMEs under the marine-economy context. The study finds that Yantai's marine economy has moved beyond the stage of traditional resource exploitation and scale expansion, and is gradually evolving toward a development model that emphasizes industrial-chain extension, innovation-driven growth, green and low-carbon development, and coordinated openness. In this process, SMEs have shifted from being general market actors to becoming important supporters, innovators, and value creators within marine industrial chains. Their development shows three salient features: stronger embeddedness in marine industries, a deepening innovation orientation, and a rising trend toward green, digital, and collaborative transformation. Nevertheless, Yantai's SMEs still face a series of constraints, including insufficient participation in high-end segments of industrial chains, limited access to innovation resources, high costs of green and digital transformation, and relatively weak capabilities in outward market expansion. The findings suggest that the marine economy affects SMEs not simply through industrial "pull effects," but through a deeper restructuring of firm capabilities and competitive logic.