Studying the effects of climate change on tropical streams
Contributed by: Alonso Ramirez Twitter: @ARamirezLab
Animals, Aquatic, Biodiversity, Central America, Climate change, Community ecology, Conservation, Costa Rican, Disturbance, Ecology, English as Second Language, Environmental change, Field, Freshwater, Fundamental research, Hispanic, Immigration status, Latino/a/x, North America
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View and download in google slides here.
This research is in review to be published. You can learn more about Alonso’s research at his website here.
Slide 1: Researcher’s Background
Dr. Ramirez is a professor for the Applied Ecology department at NC State. He studies tropical streams, invertebrates, and urbanization.
PB: Why did you become a biologist?
AR: I fell in love with biology since an early age, I was particularly attracted to insects and other creatures and wanted to learn more about them. Initially, I started by learning the names of things (taxonomy) and later became interested in ecology to understand what animals do in their ecosystems.
PB: What is your favorite part about your job?
AR: The best part of my job is to conduct research. As a professor at a university I have the ability to investigate exciting research questions, new projects all the time. It is always fun to discover new questions and dedicate time to answer them.
PB: What obstacles have you overcome to get where you are?
AR: I am Costa Rican and to obtain a graduate degree and a job in ecology I had to move to the USA. That was difficult, I love Costa Rica and all its biodiversity. Also, English is my second language and it is challenging to work and communicate in a different language.
PB: What advice do you have for aspiring biologists?
AR: Biology encompasses many fields, some related with humans and some with ecosystems. There are options for all, whether you enjoy working on a computer or hiking in the woods, there is a field of biology that will fit perfectly with you. So, explore the diversity of topics that fall within the field of “Biology”.
PB: Do you feel that any dimension of your identity is invisible or under-represented/marginalized in STEM?
PB: Can you elaborate on your answer above?
AR: As a Hispanic, I feel like we are not as well represented in science as we should be based on demography.
Slide 2: Research Overview
Take home message of study
Hurricanes are increasing due to climate change, with severe impacts on ecosystems. The rapid increase in water flowing through streams can have dramatic effects on many stream components. Hurricanes remove branches and leaves from riparian vegetation, removing a main source of food for aquatic organisms (leaf litter) and allowing for algae to grow more abundantly. Canopy cover, or the shade over the stream, is important because it helps maintain lower stream temperatures that many aquatic organisms need to survive. In this study, Alonso looked at the difference in canopy cover before and after Hurricane Maria hit Puerto Rico and how this disturbance impacted Mayfly larvae that live in the streams. Alonso found that immediately after the hurricane, canopy cover was drastically reduced, with some mayfly species declining and some benefitting from this disturbance.
Quebrada Prieta is a stream in the Luquillo Experimental Forest in Puerto Rico. These three images show the same stream location before, immediately following, and several years after Hurricane Maria hit this site.
Slide 3: Key Research Points
Top figure: Canopy cover at Quebrada Prieta is shown over time. This time period represents before, during, and after Hurricane Maria. There is a dramatic decrease in canopy cover shown in October 2017, with a gradual increase approaching the original shade conditions of the site by the summer of 2022.
Bottom figures: Alonso had been documenting the abundance of different mayfly species in the stream before the hurricane, and continued to do so through 2018. The yellow line indicates the timing of Hurricane Maria. In these two graphs, one species (left) decreases after the hurricane due to a lack of leaf litter, its main food resource. The second species (right figure) benefitted from the disturbance because it feeds on algae that became more abundant after the hurricane removed canopy cover.
Dr. Ramirez’s work reveals the impacts of hurricanes on streams, how hurricanes change the food resources available to aquatic organisms, and the recovery process from the disturbance. It also shows how these disturbances may shift the invertebrate community, benefitting some species and negatively impacting others. With increasing frequency of hurricanes and other severe weather predicted as a consequence of climate change, this information can give us valuable information as to the stability and recovery of important ecosystems.