Diet of the Antarctic krill (Euphausia superba Dana): II. Selective grazing in mixed phytoplankton assemblages

Influence of oceanographic features on spatial and interannual variability of phytoplankton in the Bransfield Strait, Antarctica

“…Therefore, a shift from a diatom-to a cryptophyte-dominated community can significantly affect food-web trophic interactions (Haberman et al, 2003). In this work, a predominance of cryptophytes/flagellates was observed in the 2003, 2004 and 2008 summers, in contrast to the 2009 summer, when diatoms were more abundant.…”

“…Concerning grazer-prey associations, the Antarctic krill feeds more efficiently on diatoms than on cryptophytes, while salps are less selective and prey upon a wide spectrum of phytoplankton groups and size classes (Haberman et al, 2003). Therefore, a shift from a diatom-to a cryptophyte-dominated community can significantly affect food-web trophic interactions (Haberman et al, 2003).…”

Iron limitation across chlorophyll gradients in the southern Drake Passage: Phytoplankton responses to iron addition and photosynthetic indicators of iron stress

“…The smaller size of phytoplankton found on the shelf is also consistent with light stress, as smaller phytoplankton with greater surface area to volume ratios are more successful at harvesting light under low-light conditions. However, grazing pressure on larger phytoplankton from abundant krill may also alter the phytoplankton community size structure and potentially limit increases in phytoplankton standing stocks (Haberman et al 2003). Although we are not able to thoroughly assess limitations on shelf phytoplankton biomass in this analysis, identifying constraints on shelf biomass is important, not only for the shelf ecosystem, but also for understanding conditions allowing bloom development after the mixing of ACC and shelf waters.…”

Individual and interactive effects of warming and CO<sub>2</sub> on <i>Pseudo-nitzschia subcurvata</i> and <i>Phaeocystis antarctica</i>, two dominant phytoplankton from the Ross Sea, Antarctica

“…It is possible that N and C export per unit P may decrease with a phytoplankton community shift from P. antarctica dominance to diatom dominance (Arrigo et al, 1999;Smith et al, 2014a, b;Xu et al, 2014). However, food web effects may compensate for the effects of temperature on biogeochemical cycles, as diatoms are a preferred food source for zooplankton grazers, compared to Phaeocystis (Knox, 1994;Caron et al, 2000;Haberman et al, 2003).…”

“…Zhu et al: Individual and interactive effects tica are higher than those of diatoms, and thus they contribute unequally to the carbon, nitrogen, and phosphorus cycles (Arrigo et al, 1999. Diatoms are preferred by many planktonic herbivores over P. antarctica, and so the two groups also differentially influence the food webs of the Southern Ocean (Knox, 1994;Caron et al, 2000;Haberman et al, 2003). Arrigo et al (1999) suggested that the spatial and temporal distributions of P. antarctica and diatoms in the Ross Sea are determined by the mixed layer depth, while Liu and Smith (2012) indicated that temperature is more important in shaping the distribution of these two dominant groups of phytoplankton.…”