Relationships between δ¹⁵ N values of mesozooplankton and the N₂-fixation rate of diazotrophs in the Pacific Ocean
Crumley, Mary L
MetadataShow full item record
Nitrogen is an essential element in any ecosystem (Duce et al. 2008); however, nitrogen is often limited in marine systems and prevents primary growth (Gruber and Galloway 2008; Duce et al. 2008). In the oligotrophic oceans, diazotrophs, such as Trichodesmium, fix atmospheric nitrogen (N₂) into biomass through a process known as nitrogen fixation (Carpenter et al. 1999; Duce et al. 2008; Church et al. 2009). While the knowledge of nitrogen movement through the marine cycle is primitive, previous research suggests one way new nitrogen is cycled is through the predatory behavior of mesozooplankton (Robinson 2001; McClellan and Montoya 2002; Montoya et al. 2002). While several links have been established through previous research between diazotrophs and mesozooplankton in the Atlantic Ocean, few researched has been performed in the Pacific Ocean. In 2007, Joseph Montoya's lab performed a research cruise in the Pacific Ocean from Australia to Fiji. Zooplankton and particle samples were collected and δ¹⁵ N values as well as diazotroph N contributions were analyzed. While some zooplankton samples resemble δ¹⁵ N trends found in the tropic and subtropic Atlantic, other zooplankton show no observable trends.