摘要
This paper describes the interaction of physics, chemistry and biology in controlling phytoplankton biomass and production for a region along 152°E between 40°S and 50°30′S in summer 1990. The physical structure in the upper 500 m included a warm core eddy in the north, a cold core feature at 46°30′S, and two major fronts, the Subtropical Convergence and the Subantarctic Front, between 49°S and 50°30′S. In the region between the warm core eddy and the southern fronts, Subantarctic Mode Water was capped by a high salinity layer with a subsurface salinity maximum. Surface nitrate increased from zero in the north to more than 15 μM in the south in a series of steps across surface fronts associated with mesoscale features. Phytoplankton column biomass, estimated column production (based on P vs I incubations) and estimated mixed layer growth rates were moderate throughout the transect (typically 30 mg Chl.a m-2, 300 mgC m-2 d-1, and 0.27 d-1, respectively). Surface nitrate seems unlikely to be seasonally depleted south of 46°30′S, and this region shows characteristics similar to other high nutrient but low chlorophyll regions. Episodic wind mixing appears to play an important role in summer resupply of nitrate to the mixed layer in the central third of the transect. Over the southern half of the transect, changes in surface pH and derived pCO2 as a function of nitrate concentrations were consistent with DIC uptake at Redfield ratios. The derived surface pCO2 values showed undersaturation by 50–100 μatm throughout the transect./
摘要译文
本文描述了物理，化学和生物学在控制1990年夏季40°S和50°30''''之间152°E区域浮游植物生物量和产量的相互作用。上部500米的物理结构包括北部的暖核涡，46°30''''的冷核部分，以及两个主要的前沿，即亚热带收敛和亚南极锋，在49°S和50°30''''之间。在温暖的核心涡旋和南部前缘之间的区域，亚南极模式水被高盐度层覆盖，最大盐度为盐度。通过与中尺度特征相关的表面前沿的一系列步骤，表面硝酸盐从北部的零增加到南部的15μM以上。浮游植物柱生物量，估计柱生产（基于P vs I孵育）和估计的混合层生长速率在整个样带中是中等的（通常为30 mg Chl.a m sup -2 / sup，分别为300 mgC m sup -2 / sup d sup -1 / sup和0.27 d sup -1 / sup。表面硝酸盐似乎不太可能在46°30''''的南部季节性消耗，该区域显示出与其他高营养素但低叶绿素区域相似的特征。在夏季将硝酸盐再补给到横断面中央三分之一的混合层中，偶发性风混合似乎起着重要作用。横断面的南半部，作为硝酸盐浓度的函数的表面pH和衍生的pCO 2的变化与Redfield比率下的DIC摄取一致。衍生的表面pCO 2值在整个样带中显示50-100μm的欠饱和度./
L.A.Clementson[a];J.S.Parslow[a];F.B.Griffiths[a];V.D.Lyne[a];D.J.Mackey[b];G.P.Harris[c];D.C.McKenzie[a];P.I.Bonham[a];C.A.Rathbone[a];S.Rintoul[b];. Controls on phytoplankton production in the Australasian sector of the subtropical convergence[J]. Deep Sea Research Part I: Oceanographic Research Papers, 1998,45(10): 1627-1661