The phenomena identified in the image is Putrefaction.
Putrefaction is a complex process involving the decomposition of organic matter, primarily proteins, by bacteria and fungi. It results in the formation of malodorous compounds, color changes in tissues, and gas production. This is an essential stage in the natural recycling of organic materials. In microbiology, understanding putrefaction is crucial for studying ecosystems, as well as the science of decomposition in forensics.