Publications by authors named "Rong-Quen Jan"
Article Synopsis
- Recreational scuba diving heavily relies on identifying fish species to enhance the diving experience, which can be challenging due to their unpredictable occurrence.
- Two methods (arithmetic mean and geometric mean) were developed to categorize fish species based on their long-term visibility at dive sites.
- Results show that categorizing fish into common, frequent, occasional, and rare categories allows for better planning, indicating that at least 25 surveys are needed to accurately determine which fish can attract divers.
To assess the effect of cage fish-farming on the coral reef ecosystem off Xiaoliuchiu Island, southern Taiwan, geographical differences in the food chain of each of two damselfishes, Pomacentrus vaiuli and Chromis margaritifer, were examined using a stable-isotope approach. For each damselfish, individuals were found to consume similar foods at all sites. However, specimens collected at sites near the cage farm (as the experimental sites) exhibited lower δ(13)C and higher δ(15)N signatures compared to those from reference sites.
View Article and Find Full Text PDFSeveral coral reefs of Nanwan Bay, Taiwan have recently undergone shifts to macroalgal or sea anemone dominance. Thus, a mass-balance trophic model was constructed to analyze the structure and functioning of the food web. The fringing reef model was comprised of 18 compartments, with the highest trophic level of 3.
View Article and Find Full Text PDFArticle Synopsis
- The Danshuei River estuary is a hypoxic environment heavily impacted by untreated sewage, affecting its ecological balance.
- The food web model created using Ecopath with Ecosim shows that detritivory (consuming decomposed organic matter) is more vital than herbivory (plant-eating), with a shorter food-chain length due to low biomass of top predators.
- Overall, the estuary operates as a heterotrophic ecosystem, meaning it consumes more organic matter than it produces, indicated by a negative estimate of primary production versus respiration.