Final answer:
The blue-green discoloration in the lower abdomen during decomposition is primarily due to the production of sulfhemoglobin by anaerobic bacteria as they decompose. Hydrogen sulfide gas released by sulfate-reducing bacteria contributes to this discoloration. The process is influenced by factors like oxygen levels and pH.
Step-by-step explanation:
The blue-green discoloration in the lower abdomen during decomposition is commonly attributed to the presence of sulfhemoglobin and other pigments associated with the process of putrefaction. In the absence of oxygen, anaerobic bacteria begin to break down soft tissues. These bacteria release enzymes that cause the destruction of hemoglobin, resulting in the formation of sulfhemoglobin, which leads to the greenish-blue appearance. An example of bacteria involved in this process are the sulfate-reducing bacteria, which produce hydrogen sulfide gas while decomposing organic matter, as seen in figure 11.10 describing the green color in coastal waters from hydrogen sulfide-producing bacteria.
Deeper understanding of the erythrocyte lifecycle, as summarized in Figure 18.8, explains that the breakdown of hemoglobin can lead to various colors due to the presence of different pigments, such as biliverdin, bilirubin, stercobilins, and urobilins. These pigments are responsible for the color of bruises, jaundice, feces, and urine under normal conditions. During decomposition, similar processes take place, leading to the characteristic discoloration seen in decomposing tissue.
It's also important to note that factors like pH and oxygen levels, as mentioned in references to bogs, significantly affect the rate and nature of the decomposition processes, influencing the predominant microorganisms and chemical reactions taking place.