Temperature Effects on Growth of Alaria marginata, Saccharina latissima, and Costaria costata

Abstract

To understand the long-term effects of climate change, it is essential to understand the short-term effects influenced by abiotic factors such as temperature. My study serves as a step towards understanding the effects of climate change. I used a combination of observational and experimental approaches to analyze the impacts of temperature on the growth of three species of kelp: Alaria marginata, Saccharina latissima, and Costaria costata. I hypothesized that there would be less growth at higher temperatures for all kelp species. Common gardens were created in outdoor seawater tanks under 3 temperature treatments (14 ° Celsius, 18 ° Celsius, and ambient) to measure growth over the experimental period. A Pocket PEA Portable Fluorometer was utilized to determine whether temperature affected chlorophyll fluorescence levels. There was no significant effect of temperature on the overall growth of all the kelp species. However, there was a significant effect of temperature on the meristem growth, suggesting there was a decrease in growth when temperatures increased. The fluorometer indicated no significant difference in chlorophyll fluorescence between each temperature treatment, but there was a suggestive increase in levels of fluorescence after 6 days of growth.