Effects of an estuarine plume-associated bloom on the carbonate system in the lower reaches of the Pearl River estuary and the coastal zone of the northern South China Sea
Effects of an estuarine plume-associated bloom on the carbonate system in the lower reaches of the Pearl River estuary and the coastal zone of the northern South China Sea
复制标题
河口羽流水华对珠江口下游和南海北部沿岸碳酸盐岩系统的影响
DOI：
10.1016/j.csr.2007.04.018
复制
发表时间：
2008-07-15
影响因子：
2.3
通讯作者：
Chen, Zhaozhang
中科院分区：
文献类型：
--
作者：
Dai, Minhan;Zhai, Weidong;Chen, Zhaozhang
2001年5-6月，我们在珠江口和南海中国北部的一次航行中，观测到了一次由强降水引起的大型河口羽流下游的浮游植物水华。这股烟羽向河口和邻近沿岸地区输送了大量营养物质，并加强了层结作用，刺激了香港附近和离岸地区的浮游植物大量繁殖。在开花期间，生物量(Chla)增加了几倍(0.2-1.8mgChl L-1)。水华事件期间，表层浮游植物群落结构发生了显著变化，从以微浮游植物为主的群落结构转变为以微型浮游植物为主的群落结构(>；20亩)。除了Chla增加外，我们还观察到PCO(2)的显著下降，生物对溶解无机碳(DIC)的吸收，以及与之相关的溶解氧和pH的增加，表明在开花期间光合作用增强。在开花期间，我们估计DIC净下降100-150 mU/kg(-1)，TALK增加0-50 mU/kg(-1)。水华高峰期的平均海-气CO2通量约为-18mmolm(-2)d(-1)。对于平均水深为5m的表层，估算了70-110 mmolm(-2)d(-1)的很高的表观生物二氧化碳消耗率。这个值比估计的海-气交换率高2-6倍。皇冠版权所有(C)2008由爱思唯尔有限公司出版。保留所有权利。
We observed a phytoplankton bloom downstream of a large estuarine plume induced by heavy precipitation during a cruise conducted in the Pearl River estuary and the northern South China Sea in May-June 2001. The plume delivered a significant amount of nutrients into the estuary and the adjacent coastal region, and enhanced stratification stimulating a phytoplankton bloom in the region near and offshore of Hong Kong. A several fold increase (0.2-1.8 mu g Chl L-1) in biomass (Chl a) was observed during the bloom. During the bloom event, the surface water phytoplankton community structure significantly shifted from a pico-phytoplankton dominated community to one dominated by microphytoplankton (> 20 mu m). In addition to increased Chl a, we observed a significant drawdown of pCO(2) , biological uptake of dissolved inorganic carbon (DIC) and an associated enhancement of dissolved oxygen and pH, demonstrating enhanced photosynthesis during the bloom. During the bloom, we estimated a net DIC drawdown of 100-150 mu mol kg(-1) and a TAlk increase of 0-50 mu mol kg(-1). The mean sea-air CO2 flux at the peak of the bloom was estimated to be as high as similar to-18 mmol m(-2) d(-1). For an average surface water depth of 5 m, a very high apparent biological CO2 consumption rate of 70-110 mmol m(-2)d(-1) was estimated. This value is 2-6 times higher than the estimated air-sea exchange rate. Crown Copyright (c) 2008 Published by Elsevier Ltd. All rights reserved.