Sensitivity of Shannon-winner diversity index and Margalef richness index values on fauna population changes in the forest revegetation of mining closing areas in east Bolaang Mongondow regency, North Sulawesi of Indonesia

Species diversity of fauna is an indicator of the sustainability of the ecological system and is the easiest and fastest variable to measure the ecological data qualification in term of diversity and richness index values. Therefore, the urgency of biodiversity measurement activities, knowledge of the philosophy, methods, and implementation of the concept of measuring species diversity in ecological population studies is very necessary. This study was conducted to determine the level of sensitivity of the two analysis methods, including a simulation of the calculation of species diversity using Shannon-Winner Diversity Index (H’) and using Margalef Richness Index by applying various existing diversity data of fauna species population in the revegetation forest area of ​​the PT Jresources Bolaang Mongondow (JRBM) Lanut mining site, East Bolaang Mongondow Regency, North Sulawesi of Indonesia from January 2024 to December 2024. The results showed that changes in the observation data of fauna populations affected the decrease in the number of fauna species and the number of individuals in each type of fauna. These decreasing changes in the number of fauna species and the individual populations in each type of fauna would be linearly proportional to the decrease in the index values of the Shannon-Wenner species diversity (H’). However, these decreasing changes in the number of fauna species and the individual populations in each type of fauna would be proportional to the quadratic curve pattern against the Margalef Richness index values (Dmg). This revealed that the Shannon-winner diversity index value (H’) is more sensitive than the Margalef richness index value (Dmg) in the changes of the existence data of fauna populations in the revegetation forest areas.