Factors that influence decomposition timeline estimation in Anambra state, Nigeria

Abstract

Abstract Background Decomposition timeline estimation is one of the key tools used in homicide cases to unravel the mystery behind the time of death of a victim. Decomposition timeline is the time take for a carcass to decay from time of death to skeletonization. Several events occur during this timeline. These events are controlled by certain autolytic and putrefactive factors. Other factors also play a role in the determining the rate of decomposition. However, putrefactive factors aid the eventual breakdown of a carcass. The putrefactive factors are flora activities, fauna activities, soil physicochemical properties, nature of soil, and climatic factors. This study aimed at investigating the factors that play vital role in the estimation of decomposition timeline of Sus scrofa domestica placed on the soil surface in Anambra state, Nigeria. Results Findings from the study showed that the factors that statistically (p < .05) influenced the rate of decomposition includes atmospheric temperature, humidity, precipitation, and soil salinity. ANOVA demonstrated that the effect of the 6 predictors was significant for predicting time of decomposition F (6, 48) = 771.118, p < .001. There is a high degree of correlation between the predictors and time, R = .995. This prediction model can explain 9711.839 variables of all possible factors of decomposition but cannot explain 88.161 variables. Result from the prediction model for rate of decomposition showed a high degree of correlation between the predictors and rate of decomposition, R = .986. This model can explain 2438.799 variations in the variables of all possible factors of decomposition but cannot explain 70.334 variations in the variables. Conclusions The factors that affect the rate of decomposition include atmospheric temperature, humidity, precipitation, and soil salinity. The prediction model for time and rate of decomposition has a high goodness of fit. The six factors identified in this study should be considered when predicting time and rate of decomposition, so as to ensure accuracy. This implies that daily atmospheric temperature should not be the only data used for predicting the rate and time of decomposition in Anambra state, Nigeria.

Keywords

• Post mortem interval estimation
• Forensic taphonomy
• Factors of decomposition timeline
• Criminal investigation