北冰洋太平洋扇区海水DMS和DMSP分布及生物周转研究

发布时间：2018-06-24 15:54

本文选题：北冰洋太平洋扇区 + DMS　；参考：《国家海洋局第一海洋研究所》2015年硕士论文

【摘要】：二甲基硫(DMS)是海洋中最重要的挥发性生源硫化物,DMS进入大气后的氧化产物对全球气候变化和酸雨的形成具有重要影响。二甲基巯基丙酸内盐(DMSP)作为DMS的前体物质,其生物地球化学过程影响着海水中DMS的浓度。生物生产和消耗是海洋中DMS和DMSP的主要来源和去除途径,决定表层海水中DMS的浓度及其海—气通量。研究海水中DMS和DMSP的空间分布及其影响因素,了解海水中DMS的生物生产和消耗速率,有助于评价海洋生源硫对大气硫化物的贡献率,加深海洋生源硫对全球气候和环境影响的认识。两极地区变化对全球气候变化具有指示和调控作用。本论文基于2014年7—8月对北冰洋太平洋扇区的现场调查研究,系统研究了DMS/DMSP分布特征及其影响因素,并考察了DMS的生物生产和消耗速率及海—气扩散通量,探讨了表层海水中DMS去除的主要途径。主要研究结果如下:1、北冰洋太平洋扇区海水DMS和DMSP的分布特征为:表层海水DMS含量以白令海最高(10.3±8.0 nmol/L),楚科奇海次之(6.3±5.8nmol/L),北冰洋最低(1.4±1.0 nmol/L);DMSPd(溶解态)、DMSPp(颗粒态)含量从高到低依次为白令海、楚科奇海和北冰洋。水温、盐度影响DMS和DMSP的含量和分布。在水温2-7oC海域,高温有利于DMS的释放,低温有助于DMSP的合成;白令海北部低盐度时有利于DMSP的释放,而在白令海和楚科奇海高盐度有助于DMSP的合成。DMS和DMSPd的分布与叶绿素a(Chl-a)无明显相关关系,DMSPp含量受Chl-a浓度的调控。2、北冰洋太平洋扇区表层海水DMS生物生产和消耗速率大小依次为:白令海楚科奇海北冰洋。DMSPd在白令海相对DMSPp对DMS的生物生产和消耗速率的控制程度更大;而在楚科奇海和北冰洋,DMSPp相对DMSPd对DMS的生物生产和消耗速率的控制程度更大,说明北冰洋太平洋扇区不同海域DMS的产生途径并不相同。3、白令海表层海水DMS的微生物消耗的生物周转时间(0.29±0.34 d)与楚科奇海和北冰洋(0.27±0.12 d)大致相当;表层海水DMS的海—气周转时间从快到慢依次为白令海(1.83±0.82 d)、楚科奇海(2.29±1.36 d)、北冰洋(5.31±4.79d);白令海和楚科奇海DMS海—气通量约为23μmol/(m2·d),是北冰洋的10多倍。调查海域表层海水微生物消耗周转时间比DMS海—气周转时间快约20倍,微生物降解相对海—气周转是表层海水DMS的主要去除途径。4、与2012年7—8月第五次北极考察结果相比,本次调查北冰洋太平洋扇区海水中DMS、DMSP的含量以及DMS海—气通量均大幅升高了数倍,楚科奇海DMS高值区范围扩大且浓度升高,这可能是调查海域水温大幅升高所致。
[Abstract]:Dimethyl sulfur (DMS) is one of the most important volatile sulfur compounds in the ocean. The oxidation products of DMS after entering the atmosphere play an important role in global climate change and the formation of acid rain. As the precursor of DMS, the biogeochemical process of DMSP affects the concentration of DMS in seawater. Biological production and consumption are the main sources and removal routes of DMS and DMSP in the ocean, which determine the concentration and air-sea flux of DMS in surface seawater. To study the spatial distribution of DMS and DMSP in seawater and their influencing factors, to understand the biological production and consumption rate of DMS in seawater, and to evaluate the contribution of marine living sulfur to atmospheric sulfides, To deepen the understanding of the impacts of marine sulfur on global climate and environment. The two-pole region change has the indication and the control function to the global climate change. Based on the field investigation of the Arctic Pacific sector in July-August 2014, the distribution characteristics of DMS / DMSP and its influencing factors were systematically studied, and the biological production and consumption rate and air-sea diffusion flux of DMS were investigated. The main ways to remove DMS from surface seawater were discussed. The main results are as follows: (1) the distribution characteristics of DMS and DMSP in the Arctic Pacific sector are as follows: the highest DMS content in the surface water (10.3 卤8.0 nmol / L) in the Bering Sea, followed by the Chukchi Sea (6.3 卤5.8 nmol / L), and the lowest (1.4 卤1.0 nmol / L) DMSPd (dissolved) DMSPP (granular state) content in the Arctic Ocean. To the lowest is the Bering Sea, The Chukchi Sea and the Arctic Ocean. Water temperature and salinity affect the content and distribution of DMS and DMSP. In the water temperature of 2-7oC, the high temperature is favorable to the release of DMS, the low temperature is helpful to the synthesis of DMSP, and the low salinity in the northern Bering Sea is favorable to the release of DMSP. However, high salinity in Bering Sea and Chukchi Sea contributes to the synthesis of DMSP. DMS and DMSPd distribution have no significant correlation with chlorophyll a (Chl-a). The concentration of DMSPp is regulated by Chl-a concentration. The order of the rate is as follows: the biological production and consumption rate of DMS is more controlled by the Arctic Ocean. DMSPd than DMSPp in Bering Sea compared with DMSPP; In the Chukchi Sea and the Arctic Ocean, DMSPp has greater control over the biological production and consumption rate of DMS than DMSPd. The results show that the pathway of DMS production in different sea areas of the Arctic Pacific sector is different. The microbial turnover time (0.29 卤0.34 d) of DMS in the Bering Sea is about the same as that in the Chukchi Sea and the Arctic Ocean (0.27 卤0.12 d), and the biological turnover time (0.29 卤0.34 d) is similar to that in the Chukchi Sea and the Arctic Ocean (0.27 卤0.12 d). The sea gas turnover time of surface water is Bering Sea (1.83 卤0.82 d),) Chukchi Sea (2.29 卤1.36 d), Arctic Ocean (5.31 卤4.79 d) and Bering Sea and Chukchi Sea (23 渭 mol/) (m2 d), is more than 10 times of Arctic Ocean). The turnover time of microbial consumption in surface seawater is about 20 times faster than that of DMS, and microbial degradation relative to sea gas turnover is the main removal pathway of surface water DMS, compared with the fifth Arctic survey in July-August, 2012. The contents of DMSN DMSP and the sea-air flux of DMS in the Arctic Pacific sector have been increased several times. The range and concentration of DMS in Chukchi Sea have been expanded. This may be due to the increase of water temperature in the investigated sea area.
【学位授予单位】：国家海洋局第一海洋研究所
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P734

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