沙尘和灰霾沉降对黄海春季浮游植物生长的影响

大气沉降可为上层海洋带来生物可利用性的营养元素(如N、P、Fe等),从而改变浮游植物的初级生产过程及群落结构,并影响海洋的碳循环.于2014年春季在南黄海开展2次船基围隔培养实验,通过人工添加沙尘、灰霾颗粒及多种营养盐来模拟大气沉降对海洋表层浮游植物生长的影响,结果表明:南黄海北部B07站浮游植物生长主要受到磷限制;南黄海中部H10站则主要受氮限制.沙尘添加在B07站和H10站均显著促进小型和微型浮游植物生长,对微微型浮游植物生长的促进作用不明显.灰霾添加在B07站对浮游植物生长总体呈现抑制作用,且主要抑制小型和微型浮游植物生长,对微微型浮游植物则为先抑制后促进;在H10站对浮游植物的影响整体呈现先抑制后促进,培养前期对各粒级浮游植物均有抑制作用,培养后期对微型和微微型浮游植物有促进作用.

Impacts of dust and haze particles deposition on phytoplankton growth in Yellow Sea during springtime

Atmospheric deposition can supply external nutrients (such as N, P, Fe, etc.) to the upper ocean and promote primary production and community of phytoplankton, posing significant impact on the carbon cycle in ocean. In this study, dust and haze particles as well as nutrients were added to surface seawaters collected in different zones of the South Yellow Sea for incubation experiments during two cruise campaigns in spring 2014. For the seawaters collected in the northern part of the South Yellow Sea (B07 Station), the experimental results showed that the phytoplankton growth was mainly subject to P-limitation. In comparison, the experimental results for seawaters collected at H10 station situated at the middle part of South Yellow Sea showed a typical N-limitation. For seawaters collected at both B07 and H10 stations, dust additions significantly promoted the growth of phytoplankton, especially the micro- and nanophytoplankton growth. However, no promotion was found for the growth of picophytoplankton. For seawaters collected at B07 station, haze particle additions inhibited the growth of phytoplankton, mainly for micro- and nanophytoplankton. However, haze particle additions were found to promote the growth of picophytoplankton after an initial 5 d inhibition. The inhibition was also observed when haze particles were added to seawaters collected at H10 station. However, the additions can promote the growth of nano- and picophytoplankton after an initial inhibition for 6 d.