Abstract Detail

Conservation Biology

Durr, Norbaya Jameela [1], Ksiazek-Mikenas, Kelly [2].

Forbs grown on green roofs may have unrecognized potential to sequester atmospheric carbon.

Increased atmospheric CO₂‚ concentration caused by deforestation and fossil fuel combustion will continue to negatively impact most plant species and their ecological roles within ecosystems. Reforestation efforts can counteract such effects but are not enacted swiftly enough. Underutilized urban spaces, such as green roofs, may aid in atmospheric carbon sequestration however, small succulent Phedimus (formerly Sedum) species are typically the predominant species planted on green roofs. Diverse plant communities may sequester additional CO₂, but plants grown on green roofs tend to have shorter above ground stature and prostrate growth compared to ground-level habitats, primarily due to temperature, light and water stress. However, due to these harsh environmental conditions, plants on green roofs may allocate more carbon below ground than above ground, resulting in greater CO₂‚ sequestration than would be predicted by above-ground measurements alone. Additionally, if plants on green roofs were grown in the presence of symbiotic arbuscular mycorrhizal fungi (AMF), this relationship could increase nutrient, mineral, and water uptake, potentially increasing plant survival and growth. In this experiment, we hypothesized that native prairie plants grown in stressful green-roof conditions with added AMF would sequester more carbon than those grown in ideal conditions without AMF inoculum. To test our hypothesis, we collected naturally AMF-colonized soil from a 7-year-old green roof and used commercially available Rhizophagus intraradices as a second inoculum. We grew 10 locally native forb species in the two AMF-inoculum treatments and the control without AMF; in 1) a laboratory to simulate ideal conditions and 2) a greenhouse to simulate green roof conditions. Our data reveals that most species had higher germination, survival, leaf and root length and biomass in the commercial inoculum compared to the natural green roof inoculum. Additionally, while many species had greater above-ground growth in the ideal lab conditions, biomass was typically greater in the individuals grown in the drier, hotter greenhouse. A current experiment is underway on a green roof and nearby ground-level garden to test the applicability of these results. Overall, our findings thus far support the hypothesis that green roofs could have unrecognized potential to aid in future important carbon sequestration strategies, particularly when plants are grown in the presence of a commercial AMF inoculum.

1 - Elmhurst University, Biology, 3610 w 87th ST., Chicago, Il, 60652, United States
2 - Elmhurst University, 190 S Prospect Ave, Elmhurst, Illinois, 60126, USA

Keywords:
green roof
arbuscular mycorrhizal fungi
Carbon sequestration
grassland forb
Rhizophagus intraradices.

Presentation Type: Oral Paper
Session: CB03, Conservation Biology 3
Location: /
Date: Wednesday, July 21st, 2021
Time: 4:45 PM(EDT)
Number: CB03008
Abstract ID:880
Candidate for Awards:None