Keywords: 
• southern Guizhou /
• LateCarboniferous /
• coral reef /
• ecosystem

Abstract: A largescale metazoa framebuilding reef system was developed in the southern Guizhou Province during the LateCarboniferous, which was rarely reported in the geological records after the F/F mass extinction event. The reef structure was mainly built by rugosan corals Fomitchevella, and is, from the bottom to top, composed of four subunits: bioclastic shore, patchy reef and mud mound, bioclastic limestone and Fomitchevella framestone. The organisms in ecosystem of each unit are variable, due to different tropic level in which producers, consumers and decomposers are differentiated in view of their behavior in the food chain, reefbuilder and reefdwellers in view of their functions in the reefbuilding process. The analysis shows that the organisms play different roles in reefbuilding process due to their status in the food chain. According to the contribution of the organisms and energy and macronutrient flow diagram, a new understanding that the coral reef ecosystem rapidly uptake the macronutrient is obtained. According to the composition and the relationship of the organisms, the development process of the ecosystem is supposed based on the organisms and their spatial location relationships, and can be divided into bioclastic shoal stage, patchy reef and mud mound stage, Fomitchevella colonizing stage and Fomitchevelladominant stage. The different behaviors and growth forms of Fomitchevella and Ivanovia cf. manchurica determined their status in the coral reef ecosystem, and the ecosystem maintained survivorship and development of the species by rapidly up taking the macronutrient.