5. Conclusions
Significant seasonal biological responses to physical processes were
observed in the central YS (Fig. 9). During winter, nutrient-rich water
was observed coincidently with the occurrence of the YSWC (Fig. 4).
Prasinophytes were abundant and the main contributors of Chl b in
the YSWC water. The mechanism/process of the spring bloom was
very complex and unique. However, the YSWC was suggested to be
one of the important players. A very strong spatial heterogeneity was
observed in the physical, chemical and biological parameters in the
central YS during the YSCWM occurrence (Figs. 2, 7 and Table 2). A
low Chl a biomass (0.2 mg m−3) and a low contribution of diatoms to
the total Chl a biomass (30%), with a high contribution of cyanobacteria
(36%), were observed in the central YS in August when the YSCWM
prevailed, and a high contribution of chrysophytes (38%) was observed
in October when it was decaying. All these results were considered as
the characteristic physical–chemical–biological response of the ecosystem
in the central YS.