Functional diversity of farmland bees across rural–urban landscapes in a tropical megacity

Urban Farm DB summary

This study sampled bees across three seasons in 36 conventionally managed vegetable farms along an urbanization gradient in Bengaluru, a tropical megacity in India, to assess how urbanization affects the functional diversity of farmland pollinators. Functional responses were trait-specific: larger, solitary, cavity-nesting, and specialist bees benefited from urbanization, while ground-nesting bees increased in urban areas, in contrast to patterns seen in temperate cities. However, overall bee abundance and the abundance of social bees (85% of all bees sampled) decreased with urbanization, which the study identifies as a threat to crop pollination. Crop diversity promoted taxonomic and functional diversity, flower resources promoted abundance, and exotic plants decreased functional diversity and bee specialization. The authors recommend preserving semi-natural vegetation such as hedges, diversifying crops, maintaining native vegetation along field margins, and controlling invasive exotic plants.