南黄海夏季低氧、贫氧长期时空演变与机制

根据1977—2016年历年8月南黄海断面标准层调查资料,采用时空分析等方法,研究了南黄海断面8月份低氧、贫氧长期时空演变与机制。溶解氧(DO)含量与表观耗氧量(AOU)年际变化分别有4种主要时空模态,溶解氧含量第一模态与表观耗氧量第一、二模态是断面海域显著线性低氧、贫氧趋势的主要影响分量,溶解氧第二~四模态与表观耗氧量第三、四模态为准平衡态长期变化。南黄海夏季低氧、贫氧变化的主要机制是生物活性组分(BAC)耗氧过程增多和增强,低氧和贫氧准平衡态长期变化的主要机制是生物活性组分、饱和溶解氧与海流输送的增减氧效应处于准平衡态状态。黄海冷水团中平均溶解氧含量、表观耗氧量存在显著线性低氧、贫氧趋势。南黄海夏季表层海气氧通量强度显著线性减弱,并且呈现“氧源”、“氧汇”相间变化。黄海夏季风生环流、海气氧通量强度逐渐减弱为黄海夏季低氧、贫氧发展提供了物理条件。目前黄海溶解氧含量、表观耗氧量场季节循环时空分布已经发生显著改变。     

水色遥感大气校正方程的研究进展

大气校正是水色遥感研究中必不可少的一步,文中概括总结了对于一类水体、二类水体的大气校正以及在每类水体中对气溶胶单散射、复散射两种情况下的大气校正方法,列出了比较实用的计算流程。     

Schooling behaviour and environmental forcing in relation to anchoveta distribution: An analysis across multiple spatial scales

The Peruvian anchovy or anchoveta (Engraulis ringens) supports the highest worldwide fishery landings and varies in space and time over many scales. Here we present the first comprehensive sub-mesocale study of anchoveta distribution in relation to the environment. During November 2004, we conducted a behavioural ecology survey off central Peru and used a series of observational and sampling tools including SST and CO₂ sensors, Niskin bottles, CTD probes, zooplankton sampling, stomach content analysis, echo-sounder, multibeam sonar, and bird observations. The sub-mesoscale survey areas were chosen from mesoscale acoustic surveys. A routine coast-wide (2000 km) acoustic survey performed just after the sub-mesoscale surveys, provided information at an even larger population scale. The availability of nearly concurrent sub-mesoscale, mesoscale and coast-wide information on anchoveta distribution allowed for a unique multi-scale synthesis. At the sub-mesoscale (100s m to km) physical processes (internal waves and frontogenesis) concentrated plankton into patches and determined anchoveta spatial distribution. At the mesoscale (10s km) location relative to the zone of active upwelling (and age of the upwelled water) and the depth of the oxycline had strong impacts on the anchoveta. Finally, over 100s km the size of the productive area, as defined by the upwelled cold coastal waters, was the determining factor. We propose a conceptual view of the relative importance of social behaviour and environmental (biotic and abiotic) processes on the spatial distribution of anchoveta. Our ecological space has two y-axis; one based on self-organization (social behaviour), and the other based on the environmental processes. At scales from the individual (10s cm), to the nucleus (m), social behaviour (e.g. the need to school) drives spatial organization. At scales larger than the school, environmental forces are the main driver of fish distribution. The conceptual ecosystem models presented in this paper may provide the final links needed to develop accurate forecasts of the spatial distribution of anchoveta over multiple scales.     

浅色黄姑鱼幼鱼耗氧率、排氨率及窒息点的初步研究

呼吸和排泄是鱼类代谢活动的重要特征,是鱼类生物能量学研究的重要内容之一,对于评估鱼类在水生态系统中的作用、物质循环、能量流动以及养殖容量等具有十分重要的意义。通过了解耗氧率和排氨率与各种因素的相互关系及变化规律可以了解鱼体的代谢水平和活动规律等,可为鱼类的养殖生产、新品种培育、移植驯化、养殖水体水质调控和活体运输等提供科学依据。有关鱼类耗氧率的研究,国内已有许多文献[1-11],但关于排氨率的研究相对较少,目前已见有牙鲆、犬齿牙鲆、大西洋鲆等种类的报道[12-14]。     

Distribution and bioturbation effects of the tropical alpheid shrimp Alpheus macellarius in sediments impacted by milkfish farming

The impact of milkfish fish pens on the distribution of the alpheid shrimp Alpheus macellarius was studied in the Bolinao area, Philippines. In addition, the impact of the alpheid shrimp on sediment biogeochemistry, including organic matter mineralization, nutrient and sulfur cycling was compared in sediments affected and unaffected by fish farming. The fish farming activity had negative impact on the distribution of shrimps by reducing the abundance up to 60% in the vicinity of the net pens, and to almost absence inside the net pens. At a farm site abandoned seven month prior to sampling the abundance of shrimps was still low and sediment pools of reduced sulfur high, indicating a slow benthic recovery. The shrimp had large physical impact on the sediments, and the mineralization rates were stimulated by the presence of the shrimp in pristine sediments, whereas the fish farm impacted sites showed high mineralization rates both in sediments with and without the presence of the shrimp suggesting that the organic matter enrichment stimulated the mineralization in these low-organic sediments, whereas the shrimp had less impact. Sulfate reduction rates and in particular pools of sulfides increased in the farm impacted sediments, and sulfate reduction was an important process for organic matter mineralization (>67%) in all sediments. Although the shrimp had minor effect on the organic matter mineralization and nutrient fluxes in the farm impacted sediments, they appeared to increase the oxidation of sulfides by increasing the zone of oxidized surface sediment and thereby improving the sediment conditions for recolonization after fish farming has ceased.     

Assessment of terrestrial factors controlling the submarine groundwater discharge in water shortage and highly deformed Island of Taiwan,Western Pacific Ocean

Submarine groundwater discharge (SGD) from seventeen sites was investigated on the coasts around Taiwan in order to verify its occurrences and to understand its characteristics. The fresh water fraction (FWF) in most pore water samples, except the Fangsan sampling site, range from 0 to 59% based on the salinity evidence. The relative low FWF evidence implies that the recirculated saline groundwater discharge (RSGD) is more important than the submarine fresh groundwater discharge (SFGD) in most sampling sites. Fangsan, which is located at the southwestern coast of Taiwan, has nearly 100% FWF in SGD. Evaluation of the relationship between the magnitude of SGD flux and geological type of the Taiwanese coast proves to be difficult because complex hydrological factors affect the SGD, rather than the coastal topography. According to the hydrological evidence, the modeled-SGD discharge is enhanced by high precipitation but is generally reduced by severe groundwater pumping. In addition, modeled-SGD has an inverse relationship with river base flow, indicating the river effect. The almost fresh SGD with flow rates ranged from 34 to 42 m/year at Fangsan deserves attention because a seven-year-long groundwater budget calculation implies that the aquifer could not supply so much fresh SGD over a large area. This suggests that a significant amount of fresh water SGD at Fangsan is derived from a point source via a fault passage, considering its geological background. Although the rudimentary salinity and stable isotope results indicate that RSGD plays an important role in SGD, the type of submarine spring discharge via fault zones may very well be the most prominent in highly deformed areas elsewhere in the world, too.     

盐度对毛蚶(Arca subcrenata Lischke)呼吸与代谢的影响

在实验室的条件下.研究盐度(16、24、32、40)对不同规格(A:(50.79±3.24)cm,B:(42.24±0.78)cm,C:(34.82±1.51)cm)的毛蚶(Arca subcrenata Lischke)耗氧率(R_0)(mg·g~(-1)·h~(-1))、排氨率(R_n)(μg·g~(-1)·h~(-1))的影响。实验表明:在实验盐度(16～40)范围内,毛蚶的耗氧率(R_0)和排氨率(R_n)与软组织干质量(0.27～1.81g)呈幂指数关系,符合公式R= aW~b,其单位体重的耗氧率和排氨率在盐度为32时达到最大,而后随着盐度的升高其值逐渐减小。     

大气环流创新模式-内外因耦合及三维地转平衡的全球大气环流模式和中尺度特大暴雨模式研究设想

 本文概述了大气环流创新模式方面的构思.     

夏季长江口缺氧区、低氧区和正常溶解氧海区浮游动物群落特征比较研究

夏季,长江口底层极易发生大面积低氧甚至缺氧.比较2016和2017年夏季长江口缺氧区(DO<2 mg/L)、低氧区(2 mg/L3 mg/L)浮游动物群落(>160μm)特征发现:2016年群落丰度和生物量均表现为缺氧区明显高于低氧区和正常海区;中小型桡足类、胶质浮游动物丰度表现...     

乳山湾外海溶氧低值区细菌多样性初步研究

采用化学裂解法从乳山湾外海溶氧低值区不同溶解氧质量浓度(3.7～7.0mg.L-1)的6个站位海水样品中提取了环境DNA样品。以试剂盒纯化后的DNA样品为模板扩增其16SrRNA基因V3区,通过变性梯度凝胶电泳、分子文库构建及DNA测序对溶氧低值区海水中的细菌群落结构进行研究。结果表明,乳山湾外海溶氧低值区不同溶解氧质量浓度的6个站位底层海水样品中的细菌群落结构是相似的,它们均由隶属于Alteromonas(交替单胞菌属)、Salegentibacter(需盐杆菌属)等10个属的18种细菌组成。系统发育分析发现这些细菌分别属于α变形菌纲(2种)、γ变形菌纲(12种)和黄杆菌纲(3种)三个大类。在乳山湾外海溶氧低值区的海水样品中细菌多样性最高的类群是γ变形菌纲。