汕头南澳—东山海域营养盐季节分布特征及其对浮游植物生长的潜在性限制  

Seasonal distribution of nutrients concentrations and the potential limitationfor phytoplankton growth in the coastal region of Nan'ao-Dongshan

作　　者：陈丹婷 柯志新[1,2,3] 谭烨辉 刘甲星[1,2] CHEN Danting;KE Zhixin;TAN Yehui;LIU Jiaxing(Key Laboratory of Tropical Marine Bio-resources and Ecology,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou 510301,China;University of Chinese Academy of Sciences,Beijing 100049,China;Guangdong Provincial Key Laboratory of Applied Marine Biology,Guangzhou 510301,China)

机构地区：[1]中国科学院南海海洋研究所,中国科学院热带海洋生物资源与生态重点实验室,广州510301 [2]中国科学院大学,北京100049 [3]广东省应用海洋生物学重点实验室,广州510301

出　　处：《生态科学》2020年第4期41-50,共10页Ecological Science

基　　金：国家科技基础资源调查专项项目(2017FY201404);国家重点研发计划(2017YFA0603204);公益性行业(农业)科研专项(201403008);国家自然科学基金项目(31670458)。

摘　　要：营养盐是水体初级生产力和渔业资源产出的重要限制性因子。2015—2017年在汕头南澳和福建东山之间的海域设置了14个采样点,分四个季节监测了该海域温盐和营养盐的空间分布特征。结果表明,调查海域北部陆源径流输入是营养盐空间分布产生差异的最重要因子,以溶解无机氮(DIN)和活性硅酸盐(DSi)受影响最为明显,春季和夏季受径流营养盐输入的影响最大,冬季受影响最小。南澳—东山海域的DIN、溶解无机磷(DIP)和DSi的浓度在表层周年平均分别为9.21、0.46和25.5μmol·L^–1,底层分别为8.96、0.50和22.5μmol·L^–1。各营养盐的浓度基本表现为由西北近海向东南远海递减,季节平均值表现为冬季>春季>夏季>秋季。冬季受闽浙沿岸流南下入侵的影响,营养盐呈现出全年最高浓度,表层平均DIN浓度是其他季节的三倍以上。春夏秋冬四个季节表层平均DIN/DIP比分别为24.3,38.8,6.7和24,底层平均分别为15.4,31.1,9.6和23.6,秋季水体的DIN/DIP比明显低于其他几个季节。总的来看,南澳—东山海域的营养盐限制在不同季节变动较大:春季近岸表现为相对磷限制,远岸水体则表现为相对氮限制;夏季和冬季都主要表现为磷的相对限制,部分远海海域在夏季甚至出现磷的绝对限制;秋季则主要表现为氮的相对限制。本研究系统阐述了南澳—东山海域营养盐限制的季节演替规律及变化机制,为该海域生态环境管理和渔业增养殖规划提供基础数据。Analyzing the distribution and limitation of nutrients is of great significance in the evaluation of the marine ecological environment.From 2015 to 2017,14 sampling stations were set up in the surface water of the Nan'ao-Dongshan coastal area, and the spatial distribution patterns of temperature, salinity and nutrients concentrations were investigatedduring four seasons. The results showed that the river discharge from the north was the most important factor regulating thespatial distribution of nutrient concentration. DIN and DSi were most affected by the riverine input, especially during springand summer. The annual average concentrations of DIN, DIP and DSi were 9.21, 0.46, and 25.5 μmol·L L–1 in the surface,and 8.96, 0.50, and 22.5 μmol·L–1 in the bottom, respectively. In general, nutrient concentrations decreased from northwestto southeast in the survey region during all four seasons, and the average values were winter > spring > summer > autumn.Nutrient concentrations showed the highest concentration in winter, in which the average surface DIN was higher than threetimes than other seasons. It could be attributed to the influence of the southward invasion of the Fujian-Zhejiang coastalcurrent in the winter. Average DIN/DIP ratios were 24.3, 38.8, 6.7 and 24 in the surface water, and were 15.4, 31.1, 9.6 and23.6 in the bottom, respectively. The DIN/DIP ratios in the autumn were significantly lower than other seasons. The potentialnutrient limitation varied greatly among different seasons in the coastal region of Nan’ao-Dongshan. In spring, it showedrelative phosphorus limitation in the inshore, while the relative nitrogen limitation in the offshore. In the summer and winter,it mainly showed relative phosphorus limitation. Absolute phosphorus limitation was found in some offshore stations insummer. While in autumn, there was mainly potential nitrogen limitation. Our results suggested that the spatial and temporaldistribution of nutrients was controlled by riverine input, coastal current, and phytopla

关 键 词：营养盐 海洋牧场 河流输入 营养盐限制 南澳 

分 类 号：P76[天文地球—海洋科学]