| 要旨トップ | 目次 | 日本生態学会第65回全国大会 (2018年3月、札幌) 講演要旨
ESJ65 Abstract


一般講演(ポスター発表) P1-051  (Poster presentation)

Resource availability determines seasonal variation of phytoplankton size structure in the Kuroshio east of Taiwan

*Lin Fan-Sian(国立台湾大学), Pei-Chi Ho(国立中央大学), Chung-Chih Chen(国立台湾師範大学), Gwo-Ching Gong(国立台湾海洋大学), Sen Jan(国立台湾大学), Chih-hao Hsieh(国立台湾大学)

Deciphering how environmental factors determine phytoplankton size structure (using normalized biovolume size spectra, NBSS) has long been a research interest. The on-going debate has centered around two classic hypotheses: First, temperature-size relationship shows that phytoplankton NBSS slopes become steeper with increasing temperature. Second, resource-size relationship shows that phytoplankton NBSS slopes become shallower with increasing resource availability. To test the hypotheses, we collected 72 sets of pico- and micro-phytoplankton assemblages to examine NBSS from 9 cruises across 4 seasons from 2012 to 2014. We found that NBSS slopes did not show significant relationship with temperature variation, which is inconsistent with the temperature-size rule. By contrast, we found a positive relationship between NBSS slopes versus resource availability, generally supporting the resource-size relationship. The only exception occurred in winter and early spring, during which small cells were dominant as the resource pulse occurred and the NBSS slopes deviated downward from the expected positive resource-size relationship. This discrepancy may be explained as the early stage of resource supply; in the initial stage of resource enrichments in oligotrophic oceans, small cells with a high surface-area-to-volume ratio uptake resource more efficiently than the larger cells. After spring, the NBSS slopes basically follow the resource-size relationship.


日本生態学会