Baseline Assessment of Insect Biodiversity and Distribution in La Salle Botanical Gardens, Pampanga, Philippines

Insects are crucial for ecosystem functions, such as pollination and food web maintenance. This study aims to assess insect biodiversity in La Salle Botanical Gardens (LSBG) in Porac, Pampanga, focusing on its grassland and forestland areas. Using rapid biodiversity assessment, this study provides baseline data on insect diversity, abundance, dominance, and evenness for conservation. Sampling employed transect line intercept and quadrat methods. Specimens were collected using different collection and preservation techniques. Insects (n = 184) were collected from August to October 2024, with specimens (n = 46) belonging to seven insect orders in the grassland and specimens (n = 138) belonging to eleven orders in the forestland. Results indicated low diversity for both sites, with values of 1.721 (grassland) and 1.684 (forestland). It also showed higher evenness in the grassland (0.885), suggesting a more balanced insect distribution and indicating low dominance values reflecting minimal competition among insect orders. Lepidoptera is the most abundant order in the grassland (28.3%), likely due to its preference for open spaces, while Orthoptera dominated the forestland (38.4%), possibly indicating an ecosystem imbalance. The low abundance of predatory insects, such as Mantodea (0.72%), may have contributed to the high Orthoptera population, potentially affecting food web stability. These findings highlight low biodiversity at both sites, influenced by environmental factors such as weather conditions, limited vegetation cover, and human disturbance, as well as methodological constraints, including sampling limitations and time restrictions.