The Large Model AI System is reshaping the new pattern of the cyberspace content ecology, and it is of great significance to explore the challenges and governance modes of content ecosystem security in the context of AIGC to enhance the effectiveness of the application of AIGC and promote the safe and orderly development of the content ecosystem. This paper takes the current situation of content ecological security under the dual-wheel drive of technology and market as an entry point, we thoroughly studied the governance dilemmas faced by AIGC at the levels of model technology, content quality, legal and liability governance, and cognitive application, and analyzed in detail the multi-dimensional causes of various risks and dilemmas, and further put forward a smart adaptive governance model of content ecological security in the context of AIGC. Constructing a smart-adaptive governance system with self-learning, self-adaptation, and self-optimization capabilities around technology, resources, systems, and environments, carrying out technological intelligent adaptive governance driven by AI clusters, environmental intelligent adaptive governance oriented to international competition, cooperation, and market demands, resource intelligent adaptive governance integrating digital identity contracts, and institutional intelligent adaptive governance featuring the dual-track parallel system of supervision and coordination are of great significance in shaping a safe, orderly, and stable content ecological pattern of AIGC.