| With increased development of the built environment, the natural landscape continues to be lost and along with it much of the habitat necessary for invertebrate survival. One way to remedy this problem is through the use of vegetated or green roofs. Vegetated roofs possess the potential to turn the sterile, impervious, and oftentimes unused environments of rooftops into viable habitats for invertebrates. This study attempted to determine exactly how successful green roofs are at creating invertebrate habitat for insects and spiders and to identify the characteristics associated with green roofs that make them successful for invertebrate establishment. The principle field methods for invertebrate collection included sweep net and pitfall traps; sampling occurred over a seven-month period (April-October) in 2010. All spiders and insects collected were identified to family level and organized and counted to calculate species abundance and richness, Simpson's diversity index (D), Shannon Weiner diversity index (H'), and Evenness (E). Analysis resulted in significance between the percent of roof covered with vegetation and insect and spider species abundance and richness. The size (area) of a green roof also significantly influenced the richness of insects and spiders present. Roof height, roof age, media depth, and vegetation type were not found to be significant factors influencing insect and spider abundance and diversity. In all cases, green roofs provided habitat for a variety of insects and spiders. |
