Final answer:
The index of diversity of insects was higher in the hedge due to its greater complexity, resource variety, and favorable conditions for diverse species interactions, compared to the homogeneous barley field environment.
Step-by-step explanation:
The index of diversity is generally higher in environments with a variety of habitats and resources, as found in hedges, compared to more homogeneous areas like barley fields. Hedges provide a greater complexity in structure and resources, which supports more diverse species and interactions between them. Factors such as food availability, predation pressures, and the presence of enemies of pests play a significant role in shaping the diversity of insect populations. These factors are likely more favorable in hedges than in barley fields, leading to higher diversity indices. Additionally, environments with a diversified structure often promote the sustainability of insect populations by providing various ecological niches and reducing the likelihood of catastrophic losses due to pests or changes in environmental conditions.