Spiderwebs as Bioindicators

Project description: Traditionally, long term studies of air pollution have been limited to stationary monitoring conducted by government bodies or large research institutions. These monitoring sites can only presume to measure so much area, and the data they collect is by its nature spatially generalized. Air pollution has been a major area of study for citizen science efforts. The development of small, low-cost air quality monitors has enabled individuals and communities to examine their own particular exposure at a fine scale. However, no low-cost sensors yet exist for the measurement of heavy metals. There is a need for low-cost air quality monitoring that can detect differences at high scale and over long periods of time. Spider webs have been used in several studies to test air quality. While some of these studies have compared their measurements to those obtained using more established techniques, they have relied upon sensors designed to measure point-in-time air pollution rather than comparing long term data. This study is guided by two main research questions: How do measurements of heavy metal air pollutants derived from spider webs compare to measurements from more traditional long term particulate matter filters? What is their potential of these techniques for citizen science? Comparing two small Baltimore neighborhoods, we were able to find significantly different percentages of metals in spiderwebs. However, the source of these differences are still unclear.

Map of study area

Click above to see a web map I created in QGIS displaying the study quadrats selected in the Brooklyn/Curtis Bay neighborhood of Baltimore. It also marks point sources of heavy metal air pollution in Baltimore (as listed in the 2018 Toxic Release Inventory database) and major highways, another significant source of heavy metals.