The decade of China's New Era has been characterized by the most profound understanding, extraordinary efforts, practical measures, rapid advancement, and notable achievements in ecological and environmental protection. While ecological environment governance has become effective, the managers' measures have gradually matured and become standardized, and the array of texts, videos, photos, and other multimodal data reflecting ecological management knowledge is expanding. The adoption of the advanced knowledge graph concept in ecological environmental protection is crucial to winning the future battle against pollution and constructing a modern environmental governance system. Focusing on the field of beautiful China and ecological civilization construction engineering, the multimodal materials of typical pollution prevention and control battles and ecological restoration engineering are used as data sources, and standard knowledge representations are formed after data integration, knowledge extraction, and knowledge fusion. The ecological management knowledge graph system is initially constructed. Specifically, it includes (1) A quantitative analysis of successful rectification case data from "Dispersed, Disrupted, and Polluted" enterprises in Shenzhen city, including the extraction of management subjects, management objects, and other entities, and the exploration of their spatial characteristics, pollution characteristics, and governance effect relationship. (2) Correlation analysis of enterprise domicile, pollutant hot spot, and urban space mutual relationship. (3) Through analysis of specific relationship between implementation behavior-destruction object-damage function in typical ecological environmental damage compensation cases in China, the knowledge graph of ecological environmental management based on ecological governance behavior-affected environmental factors-ecological service enhancement degree was extracted. (4) Finally, a comprehensive ecological management knowledge graph integrating "Dispersed, Disrupted, and Polluted" treatment and ecological environment management behavior was formed, and a graph database containing 12 ontologies, 82 entities, 4 categories, and 201 relationships was initially constructed. The research shows that the construction of China's ecological management knowledge graph through the multi-modal data of the successful cases of pollution prevention and control and the effectiveness of ecological restoration projects can form a knowledge system close to the practical needs, and contribute to the whole process of pollution control according to law, scientific pollution control and accurate pollution control. It also contributes to the analysis of "multiple causes and one effect" and "one cause and multiple effects" in identifying and assessing ecological environmental damage. We suggested to increase the application of ecological management knowledge graph in the future, accurately identify management objects, achieve scientific analysis and intelligent decision-making, promote public participation in ecological management, and accelerate the realization of the value of ecological products.