Designing with wild plants for maximizing insect richness in urban areas

Abstract

It is vital to apply suitable strategies to restore insect diversity to maintain sustainability and productivity in ecosystems. Therefore, the objective of this study was to determine the insect richness and diversity of three different planting designs in order to conserve insects and to promote such designs locally. Based on previous studies seven wild plants viz., Spermacoce assurgens, Leucas zeylanica, Tridax procumbens, Merremia tridentata, Emilia sonchifolia, Ipomoea triloba and Cyanthillium cinereum were selected as wild plants, while Z. elegans was selected as an ornamental plant. Three planting designs (3×3 m), with only wild plants, wild plants enriched with Z. elegans and only Z. elegans were established in the university premises. Monitoring of insects was done in three designs at hourly intervals from 6.00 a.m to 6.00 p.m on 6 sunny days. The highest insect richness (83) was recorded by the design with wild plants enriched with Z. elegans followed by the design with only wild plants (78) and the design with only Z. elegans (44). When consider the insect diversity, the design with wild plants enriched with Z. elegans recorded the highest diversity of H'=3.4146 followed by design with only wild plants (H'=3.045) and design with only Z. elegans (H'=1.77246). Further, the design with wild plants enriched with Z. elegans need less maintenance compared to the plot with only Z. elegans, and it could be promoted in establishing of plantings in urban areas in view of conservation of insect richness and aesthetics enhancement.