Do We Need to Care for Climate Change?

Do We Need to Care for Climate Change?

Every year, the Department of Plant Science and Landscape Architecture (PSLA) at University of Maryland (UMD) invites several research experts to present their findings as part of the departmental seminar. Last Thursday, Dr. John Kominoski, an ecologist at Florida International University (FIU), was our guest speaker. Before joining FIU as an Assistant Professor in 2013, Dr. Kominoski worked as a postdoctoral research associate at University of Georgia, USA (2010-2013) and University of British-Columbia, Canada (2008-2010). He earned his master’s degree in Biology at Loyola University Chicago in 2003 and a doctoral degree in Ecology at University of Georgia in 2008. I find Dr. Kominoski a very simple and highly intellectual person. He is an effective communicator who knows how to express his ideas very clearly and is an excellent collaborator.

Dr. Kominoski gave an interesting talk entitled, “Shifting long-term biogeochemical baselines: Enhanced marine connectivity alters plant communities and increases salt water intrusion in coastal wetland ecosystems”. Dr. Kominoski’s presentation showcased the multiple projects undertaken by his research team at the Ecosystem Ecology Laboratory at FIU. The highlights of his talk were Long Term Ecological Research (LTER), salt-water intrusion and subsidy-stress effects on carbon and nutrient cycling, long-term effects of storm-induced phosphorus loading on ecosystem productivity and nutrient dynamics in wetlands. Dr. Kominoski said, “The mangrove forests in the Florida everglades form an ecotone which serves as a critical link between the nitrogen enriched freshwater marshes and the phosphorus enriched marine environments of Florida Bay and the Gulf of Mexico.” His team is investigating the impacts of ecological regimes shifting in biogeochemical processes and ecosystem productivity.

Dr. Kominoski further reiterated that, “in 2005, Hurricane Wilma defoliated and killed mangrove trees in the Florida everglades. Since 2005, Florida has not experienced any hurricanes. Thus, they were able to test the long-term effects of hurricane Wilma in ecosystem productivity in coastal wetlands.” To better understand the effects of hurricane-induced phosphorus loading and saltwater intrusion on carbon and nutrient cycling in coastal ecosystems, they conducted a series of microcosm experiments. Results showed that high saltwater loading into freshwater marshes increased microbial respiration but decreased ecosystem productivity, shifting the net carbon balance from sink to source. Troxler et al., (2013) also hypothesized that coastal ecosystems can act as carbon sink compared to tropical forests. Thus, saltwater intrusion into freshwater marshes could potentially influence net carbon balance in coastal ecosystems.

Broadly, this presentation clearly demonstrated some of the key reasons why we needed to plan for climate change and sea level rise. Saltwater intrusion into lands, as a result of elevated sea levels, may generate large-scale ecosystem regime-shifts. For example, saltwater might increase the productivity of mangrove forests, but not of native forest, which are easily salt stressed. Decrease in ecosystem productivity due to saltwater intrusion was observed in the Eastern Shore of Chesapeake Bay where many trees are defoliated or dying. If we, as humans, do not make collaborative efforts to mitigate climate change, many habitable areas in the world will soon be under water and many agricultural fields will be no longer suitable for cultivation. Therefore, we should consider climate change mitigation as our responsibility to make our world a better place to live in the future.

Troxler, T.G., E. Gaiser, J. Barr, J.D. Fuentes, R. Jaffe et. al. 2013.Integrated carbon budget models for the Everglades terrestrial-coastal-oceanic gradient: current status and needs for inter-site comparisons. Oceanography, 26: 98–107.