School of Science Department of Ocean Science 56 Chaotic Mixing Supervisor: MAK Julian / OCES Student: POON Yiu Cho Joe / SSCI Course: UROP1000, Summer Aquatic locomotion is an important topic, studying it helps us to understand how objects are moved in liquids. Marine Animals like seahorses and jellyfish have their own unique moving pattern in the water. Jellyfish push off the water under their bells to provide movement while seahorses move by their flexible tail. What we do in this program is to find out the science behind it. In simple terms, It is about how things swim. In the report, I will examine how I started the research program on the study of aquatic locomotion and show some of my study result on it. At last, I will use python to do some simulations on the relationship between the liquid and moving object. Characterising Coral Reef Function across Anthropogenic Gradients Supervisor: WYATT Alex / OCES Student: CHEUNG Chun Fei / OST Course: UROP2100, Fall Coral reefs support many marine organisms and provide ecological services. Through stable isotope analysis of samples from different field sites, the marine food web of Hong Kong can be constructed, and anthropogenic impacts across the East-West gradient could be investigated. Sea cucumber stable isotope analysis data has shown that geographical factors have a larger impact than seasonal variation in terms of δ13C and δ15N, while the opposite is observed in δ34S. Variation in δ13C and δ15N is also small between muscle and outer wall tissues, while a larger variation is shown in δ34S. How stable isotope analysis of δ34S is used as a tool in ecological research will also be discussed below. Characterising Coral Reef Function across Anthropogenic Gradients Supervisor: WYATT Alex / OCES Student: WONG Sung Lit / BISC Course: UROP1000, Summer Increasing anthropogenic input has changed the global climate system rapidly over the year. Due to that, the drastic surge of heat content has been observed in the world’s oceans. Coral, as a marine organism, has to cope with sudden thermal stress inevitably. For coral to develop thermal resilience, the daily environmental temperature was regarded as the most impactful factor. Nonetheless, the related mechanism still remains unclear. Some studies believed the transcriptome of coral plays an important role in developing thermal resilience. Therefore, we would approach the question from transcriptomic aspect. Acropora digitifera were collected. Collected Acropora will be fragmented into nubbins and exposed to heat stress. Photosynthetic efficiency (Fv/Fm) of the nubbin would be measured and RNA would be extracted for assay at each time point. This study’s result is expected to provide insight into coral’s thermal resiling capability and function under current anthropogenic impacts.