静水压力变化对NTC热敏电阻器电学特性影响

负温度系数(negative temperature coefficient,NTC)热敏电阻器由于在窄温区内具有极高的灵敏度,在海洋领域中有着广泛的应用,但深海应用中固有的高静水压力,对器件的测温准确度造成不利影响。为了更好地认识这种现象,以珠状NTC热敏电阻器为研究对象,利用海洋环境高压模拟装置,开展了静水压力作用对器件电学特性影响的研究,固定环境温度25℃和0℃,压力范围0~60 MPa,步长5 MPa。结果显示,随着静水压力的增大,NTC热敏电阻器的电阻值减小;环境温度25℃和0℃时,5~60 MPa的静水压力造成的漂移分别为-0.11%~-2.81%、-0.19%~-2.78%,等效于温度漂移分别为0.024~0.624℃、0.036~0.535℃。这为热敏电阻器在深海温度准确测量的提升提供了指引,有利于在海洋测温领域中更好的应用。     

Temperature calibration of expendable bathythermographs

A non-destructive temperature calibration system for expendable bathythermographs (XBT) is described. A transfer standard technique has been used to estimate XBT thermistor probe-to-probe temperature variability. One-point calibration results suggest that a standard deviation of 0.025°C is typical at 10°C. Additional calibration data from nine XBT thermistors suggest that probe-to-probe temperature variability is largest at 0°C (ca. 0.03°C) and decreases uniformly to a minimum at 30°C (ca. 0.01°C).     

2017年春季季风间期南海中北部浮游植物生长与微型浮游动物摄食

Phytoplankton growth rates and mortality rates were experimentally examined at 21 stations during the 2017 spring intermonsoon(April to early May) in the northern and central South China Sea(SCS) using the dilution technique, with emphasis on a comparison between the northern and central SCS areas which had different environmental factors. There had been higher temperature but lower nutrients and chlorophyll a concentrations in the central SCS than those in the northern SCS. The mean rates of phytoplankton growth(μ_0) and microzooplankton grazing(m) were(0.88±0.33) d~(–1) and(0.55±0.22) d~(–1) in the central SCS, and both higher than those in the northern SCS with the values of μ_0((0.81±0.16) d~(–1)) and m((0.30±0.09) d~(–1)), respectively.Phytoplankton growth and microzooplankton grazing rates were significantly coupled in both areas. The microzooplankton grazing impact(m/μ_0) on phytoplankton was also higher in the central SCS(0.63±0.12) than that in the northern SCS(0.37±0.06). The microzooplankton abundance was significantly correlated with temperature in the surface. Temperature might more effectively promote the microzooplankton grazing rate than phytoplankton growth rate, which might contribute to higher m and m/μ_0 in the central SCS. Compared with temperature, nutrients mainly affected the growth rate of phytoplankton. In the nutrient enrichment treatment,the phytoplankton growth rate(μn) was higher than μ_0 in the central SCS, suggesting phytoplankton growth in the central SCS was nutrient limited. The ratio of μ_0/μn was significantly correlated with nutrients concentrations in the both areas, indicating the limitation of nutrients was related to the concentrations of background nutrients in the study stations.     

基于精细温度观测的南海东北部陆坡-深海盆底层湍流混合*

南海是存在强湍流混合的边缘海之一, 但前人对南海湍流混合的研究更多关注的是中上层, 对底层则鲜有关注。本文基于高分辨率温度传感器于2019年5月在南海东北部22个站位海底上方0.5m处持续观测4.4d的温度数据, 分析了2216~3200m深度范围内底层海水温度的时间变化特征, 并探讨了地形粗糙度和内潮对底层湍流混合的影响。分析结果表明, 南海东北部各站位底层海水的温度变化量级约为10^-4~10^-3℃; 温度变化趋势与正压潮变化趋势不同, 温度能谱显示多数站位在全日和半日频带区间出现谱峰, 温度变化更多地受斜压潮影响, 全日、半日内潮起主要调制作用。陆坡-深海盆过渡区及深海盆底层的湍动能耗散率量级为10^-10~10^-9m²∙s^-3, 涡扩散系数量级为10^-4~10^-3m²∙s^-1。观测数据未能显示底层湍流混合与地形粗糙度存在明显的相关性。底层湍流混合的空间分布与过去观测到的南海北部深海盆内潮的南北不对称性分布一致。     

A description of short period temperature fluctuations in the upper ocean

Dynamical properties of short-period temperature fluctuations are studied. Water temperature was measured continuously at several depths at the following stations: at 38°29.5′N, 141°35.8′E (100 m depth) on the continental shelf off Miyagi Prefecture in the summer of 1967, at 35°01.8′N, 139°0.8.5′E (100 m depth) in Sagami Bay in the summer of 1968, and at 32°32.2′N, 129°53.7′E (74 m depth) in Tachibana Bay in the summer of 1970. These measurements were made with a thermistor array laid down from the R. V.Tanseimaru (Ocean Research Institute, University of Tokyo) which was fixed with bow and stern anchors. Significant temperature fluctuations found at the first and the third stations are thought to be due to first mode internal waves having amplitude 3 to 5 m and period 5 to 20 minutes. The wave length of the waves is estimated to be 25 m to 400 m from the observed density structure. At the second station, we found second-mode internal waves. The period, amplitude and wave length of the waves are about 30 minutes, 1.3 m and 600 m, respectively. In all cases, the spectral density of the temperature fluctuations decreases with increase in frequency. However, the decrease obey neither the ?3 power law nor the ?5/3 power law. Coherences in the temperature fluctuations between two depths of measurement in the seasonal thermocline are significantly high in the range of frequencies lower than the local Brunt-Väisälä frequency, but are low in the higher frequency range. At the first and the third stations, the difference in the level of coherences between the lower frequencies and the higher frequencies are large. Phase differences between two depths in the thermocline are small in the lower frequency range. This suggests that the first-mode internal waves are predominant over higher-mode internal waves and over other disturbances.     

基于广义回归神经网络的全球表层海水1°×1°二氧化碳分压数据推演

表层海水二氧化碳分压是评估海洋碳源汇强度的关键参数,但其实测数据较少、时空分布极不均匀,导致二氧化碳交换通量的估算有很大的不确定性,海洋源汇特征就不能确切获取。为了解决这个难题,在收集的表层大洋二氧化碳地图(Surface Ocean CO₂ Atlas,SOCAT)实测数据集基础上,运用广义回归神经网络建立二氧化碳分压与经纬度、时间、温度、盐度和叶绿素浓度间的非线性关系,构建了1998-2018年间全球1°×1°经纬度的表层海水二氧化碳分压格点数据,其标准误差为16.93μatm,平均相对误差为2.97%,优于现有研究中的前反馈神经网络、自组织映射神经网络和机器学习算法等方法。根据构建的数据所绘制的全球表层海水二氧化碳分压的分布与现有研究有较好的一致性。     

Description of the Phytoplanktonic Community of the Oligotrophic Waters of the SE Aegean Sea (Mediterranean)

Abstract. A seasonal sampling program of five stations off the Island of Rhodes (SE Aegean Sea) was carried out in 1983–1984. Temperature, salinity, Secchi disk transparency, P-PO₄, N-NO₃, N-NO₂, N-NH₃, Si-SiO₂, and chl a were measured and phytoplankton species recorded. Cell concentrations and chl a varied seasonally. with the highest values in summer (l.2 times 10⁴ -1^--¹ total mean cells; 0.13 mgam^-3 total mean chl a ) and the lowest in winter (2.3 times 10³, 1^--¹ total mean cells; 0.06 mg^.m-^- total mean chl a ). A variation in cell abundance among stations was also noted. Quantitative relationships among the recorded taxa showed that diatoms and dinoflagellates were richer in species composition (88 and 58 total species, respectively) than coccolithophores (8 species) and other flagellates (8 species). Comparison of phytoplankton samples from different depths and stations by cluster analysis showed an irregularity or discontinuity in species associations. The SE Aegean Sea was characterized as oligotrophic on the basis of the estimated nutrient and phytoplankton concentration levels.     

南海西北部上层海洋对台风“杜苏芮”的响应分析

基于锚碇观测资料,本文分析了南海西北部陆坡区上层海洋对台风“杜苏芮”的动力学和热力学响应特征。在动力学响应方面,台风“杜苏芮”期间上层流速显著增强,混合层纬向流速可达1.20 m/s;“杜苏芮”经过后上层海水运动以近惯性振荡为主(流向顺时针旋转周期在36～40 h之间)。近惯性能量在垂向分布上存在两个高值中心,分别位于混合层和温跃层深度上。近惯性能量耗散过程的e折时间尺度约为3.7 d,我们认为能量的向下传播在局地近惯性能量衰减过程中起主要作用。对能量谱的分析表明,“杜苏芮”作用期间近惯性频率能量相对于其作用前增大了约29.4倍,而全日和半日频率(K₁和M₂)能量有所减弱。此外,能量谱显示近惯性频率存在明显的“蓝移”现象,即对于纬向和经向流速分量在400 m以浅平均的近惯性振荡频率分别为1.167 f₀和1.170 f₀(f₀为局地惯性频率)。蓝移与近惯性内波的向下传播及正的相对涡度的输入有关。在热力学响应方面,上层海洋在台风的搅拌作用下,40～250 m深度均出现较小增温,最大增温幅度接近1°C;此外70 m以浅盐度的降低可能与台风过境时的降水相关,而Ekman抽吸引起的上升流则可能对70～100 m深度盐度的升高具有重要作用。     

In Situ Time-Series Measurements of Subseafloor Sediment Properties

The capabilities and diversity of subsurface sediment sensors lags significantly from what is available for the water column, thereby limiting progress in understanding time-dependent seabed exchange and high-frequency acoustics. To help redress this imbalance, a new instrument, the autonomous sediment profiler (ASP), is described herein. ASP consists of a four-electrode, Wenner-type resistivity probe and a thermistor that log data at 0.1-cm vertical intervals over a 58-cm vertical profile. To avoid resampling the same spot on the seafloor, the probes are moved horizontally within a 20 times 100-cm^-2 area in one of three preselected patterns. Memory and power capacities permit sampling at hourly intervals for up to 3-mo duration. The system was tested in a laboratory tank and shown to be able to resolve high-frequency sediment consolidation, as well as changes in sediment roughness. In a field test off the southern coast of France, the system collected resistivity and temperature data at hourly intervals for 16 d. Coupled with environmental data collected on waves, currents, and suspended sediment, the ASP is shown to be useful for understanding temporal evolution of subsurface sediment porosity, although no large depositional or erosional events occurred during the deployment. Following a rapid decrease in bottom-water temperature, the evolution of the subsurface temperature field was consistent with the 1-D thermal diffusion equation coupled with advection in the upper 3-4 cm. Collectively, the laboratory and field tests yielded promising results on time-dependent seabed change.     

Some features of jump in water temperature in aSargassum forest

To clarify the influence of aSargassum forest on water temperature distributions observations were made inside and outside aSargassum forest off the Nagata Shore on the northern Saiki Bay open to the Bungo Channel on the Pacific side of Kyushu, Japan. About sixty thermistor probes were deployed at 0.5 m depth intervals from the bottom to the sea surface at seven stations spaced at 50–80 m distances along two transects: one inside the forest and the other outside. Water temperature was measured at five minutes intervals from 6 to 9 August 1987 with thermistor probes. The spatial standing crop distribution of theSargassum forest along the transects was investigated. A water temperature jump of about 2°C, recorded during the observation, is probably caused by an intrusion of a warm water mass from the central Bungo Channel to Saiki Bay. The water temperature jump under theSargassum forest on the rough bottom with stones occurred one to two hours behind that outside the forest (sandy bed) although the distance between the transects inside and outside the forest was only 50–80 m. It is suggested that theSargassum forest and the rough bottom would prevent intruding warm water from smoothly replacing cold water due to resistance of theSargassum species and the bottom to a current.     

南大西洋洋中脊调查区小型底栖生物丰度和生物量研究

“大洋一号”调查船于2011年5—6月在南大西洋中脊14°S附近进行了7个站位的小型底栖生物采样。共鉴定出小型底栖生物10个类群。小型底栖生物平均丰度为(60.63±54.77) ind/10 cm²,平均干重生物量为(9.42±8.92) μg/10 cm²。线虫是其中的优势类群,丰度为(47.42±47.99)ind/10 cm²,占总丰度的78.21%,另外,肉鞭动物和桡足类分别占总丰度的16.63%和3.91%。生物量前3位的类群依次为桡足类、线虫和肉鞭动物。小型底栖生物密度随沉积物深度增加而减少,约73.55%的生物丰度分布在0～2 cm层内。个体大小方面,有75.32%的小型底栖生物粒径处于32～125 μm范围内。     

沉积记录中脂类生物标志物对琼东上升流强度的指示及其影响因素初探

本文对海南岛东部上升流边缘区域(S5站位)和上升流中心区域(S10站位)两根沉积柱进行了正构烷烃和脂肪酸的分析,结合有机碳含量、粒径、碳稳定同位素(δ¹³C)等参数综合分析其有机质来源与降解特征,并利用脂肪酸硅藻丰度参数∑C₁₆∶∑C₁₈重建了研究区域上升流强度年际变化。研究结果表明:S10站位处于上升流中心附近,粒径较粗,以砂为主;S5站位处于上升流边缘区域,粒径较细,以粉砂为主;两站位柱样δ¹³C值和长短链脂肪酸比值(∑C_20-:0/∑C_20+:0)显示有机质均以海源输入为主,S10站位有机质降解程度大于S5站位。脂肪酸中硅藻丰度参数和浮游植物脂肪酸占比指示了S10站位初级生产力高于S5,并利用∑C₁₆∶∑C₁₈指征了研究区域上升流强度及年际变化趋势。上升流强度在1925-1950年,1950-1980年和1980-2008年间表现为弱、强、弱的趋势,与太平洋年代际振荡(Pacific Decadal osc...     

The extension of the Practical Salinity Scale 1978 to low salinities

The Practical Salinity Scale (PSS) 1978 is defined only for salinities within the range 2-42. We have investigated the relationship between mass-determined salinity, electrical conductivity, and temperature for salinities between 0 and 2 with the aim of developing an extension to the Practical Salinity Scale 1978. The paper presents our data, on the basis of which the following correction is proposed to extend the validity of the equations defining the scale to the entire 0-42 range:S=summin{i=0}max{5} (a_{i}+b_{i}f(t))R_{t}^{i/2}-frac{a_{0}}{1 + 1.5x + x^{2}}-frac{b_{0}f(t)}{1+y^{1/2} + y + y^{3/2}}wheref(t)=frac{(t-15)}{1 + k(t-15)x=400R_{t}y=100R_{t}and the constanta_{i}, b_{i}, andkare defind by the Practical Salinity Scale 1978.     

灰化法磷测定中不同灰化助剂的效果比较:以焦磷酸钠作为磷标样

对Na₄P₂O₇加入不同灰化助剂经不同温度(200～550℃)灼烧后磷的回收率进行了研究.所研究的灰化助剂除文献中已深入研究过的MgSO₄和Mg(NO₃)₂外,还对MgCl₂等10余种盐试剂进行了实验.结果表明,除Mg(NO₃)₂外,MgCl₂,MgAc₂,CaCl₂,Ca(NO₃)₂等均能使Na₄P₂O₇灰化后的磷完全回收(灼烧温度不低于450℃),而加入MgSO₄在任何灼烧温度下磷的回收率均低于80%,效果不佳.因此,在利用目前已被广泛应用的由Solrzno和sharp所提出的方法去分析海水中颗粒磷和总磷或有机体中的磷时,应当用MgCl₂(或MgAc₂)作为灰化助剂来取代MgSO₄.     

Thermal structures in the Kuroshio extension measured with a towed thermistor chain

Two-dimensional temperature data observed by use of a 275 meter towed thermistor chain deployed from an oceanographic research vessel USS MARYSVILLE, which cruised with a speed of 6.2 knots in July 1966 across the Kuroshio Extension in the North Pacific, are investigated. Two-dimensional variations of the distribution of the isotherms along the ship's track are analyzed with special reference to their slope, wavelength and wave height. The results show that the slope and wave height of isotherms have a tendency to increase as the temperature decreases. Even if the contribution of wave heights smaller than 1.5 m is neglected, i.e., contribution of large scale slope with a horizontal scale of 5–30 km is subtracted, this tendency is still detected. In contrast to this, the wavelength evaluated by the crest to crest method has no dependency on the temperature. Power spectrum of the isotherm depth is proportional tok ^–1.87 for 13°C andk ^–2.13 for 27°C, wherek is the wave number. It is shown that the spectra of warmer isotherms are relatively well approximated by –2 power law (Garrett and Munk spectrum) for internal waves rather than the –5/3 power law (Kolmogorov spectrum) for three dimensional isotropic turbulence.     

夏季长江口无机氮的加入与转移 偏移理论稀释曲线的解释

利用2006年夏季长江口调查数据分析了长江口海域硝酸盐(NO3-)、亚硝酸盐(NO2-)、铵盐(NH4+)大面分布,NO3-浓度呈近岸高、外海低的特征,NO2-和NH4+浓度在上海市排污口位置有高值区并向外扩散。NO3-,NH4+浓度总体上符合咸淡水混合之稀释效应,与盐度的相关系数(r2)分别为0.815,0.255,呈保守行为,而NO2-浓度与盐度的相关性系数为0.074,呈非保守行为。在确定了淡水端元和咸水端元的基础上,做出理论稀释曲线TDL(theoretical dilution line),由于上海市污染物的输入,淡水端元NO3-,NO2-,NH4+浓度不同程度地正偏于TDL,在外海深层水范围内有机颗粒矿化再生亦呈加入态势。对应高溶解氧的盐度羽状峰处,由于真光层初级生产较强,表层NO3-浓度负偏于TDL约1~19μmol/dm3,NO2-,NH4+浓度也存在不同程度的减小。在长江口最大浑浊带附近,由于高浓度悬浮物吸附NH4+而呈现明显的迁出机制。外海表层海水三氮营养盐浓度数据点偏离TDL程度较小,但在底层由于来自上层的有机颗粒耗氧分解而再生出营养盐,使NO3-,NO2-,NH4+浓度数据一般在TDL之上。     

A Survey of Estuarine Benthic, Zoo-planktonic and Phytoplanktonic Communities of Amvrakikos Gulf, Ionian Sea

Abstract. The estuarine ecosystem of the Amvrakikos Gulf, a semi-enclosed embayment of the Ionian Sea, was surveyed at 9 stations in June, 1980. Quantitative and qualitative relationships among the phytoplanktonic, zooplanktonic and benthic populations were examined and related to environmental parameters. It was found that quantitative maxima of each of the three components occurred at different stations. When stations were grouped according to a similarity index of each community, it could be shown that the stations were very similar with regard to phytoplankton and slightly less similar with regard to zooplankton. The stations differed considerably as far as the benthos is concerned. The phytoplankton also exhibited a lower species diversity (0.08-0.82 bits-indiv.^-1) than the zooplankton (1.08-2.10 bits indiv.^-1) and the benthos (0.85-5.06 bits indiv.^-1). Differences in salinity among stations showed no significant correlation with the abundance or species diversity of phytoplankton, zooplankton or benthos.     

Biomass of meiobenthic in the Bohai Sea, China

IorasMeiOfauna is a vmp imprtant pep in benthic small bo web energetica1ly duo to theirarell aize and high turnovr rates. A nde Of meMauna op be the recireulaton of nutrient8*Marine nemathe mey keep the bacterial chnies on sand grains in active phase Of gorth byfeding on bacteria, thus enhancing the recirculation Of nutrients (McIntyre, l969; Feller andWrmick, l988; MOntagna et al., l995). But energetics studie8, no matter tfor conductedon the energybudgt level for individua sPeCies or a…     

珠江磨刀门河口水位分布演变特征及其对人类活动的响应*

河口区水位受径流、潮汐、地形、人类活动等多因素影响, 其空间分布结构及变化复杂。作为河口动力结构的重要参数, 水位分布演变特征及机制的研究对水资源高效开发利用和河口治理具有重要指导意义。文章基于珠江磨刀门河口沿程马口、甘竹、江门、竹银、灯笼山和三灶6个测站1965—2016年月均余水位数据及马口站的月均流量数据, 分析人类活动影响下水位空间分布的异变, 采用双变量线性回归模型定量辨识水位分布异变的主要影响因素, 并初步讨论人类活动、动力结构、地形变化之间的相互耦合关系。结果表明, 基于平均水面形态变化参数(即曲率)可较好地指示河床冲淤变化趋势, 河段平均曲率为正, 指示河床趋于淤积, 曲率为负, 河床趋于冲刷侵蚀; 围垦、大规模挖沙、河道疏浚等强人类活动前, 磨刀门河口上、下段坡降大于中段(江门—甘竹段), 即中段存在一个水位坡降变缓的区域, 枯季低流量时中段水位坡降出现由海向陆方向的倒坡降, 强人类活动后, 余水位空间分布结构发生异变, 中段坡降增大、低流量时的逆坡降消失; 强人类活动引起的河床地形变化是磨刀门河口沿程水位空间形态发生变化的主要原因, 使口门段(三灶—竹银)和河口上段(甘竹—马口)水位曲率分别减小0.41×10^-4m·km^-2和1.04×10^-4m·km^-2, 河口中段(竹银—甘竹)水位曲率增大0.21×10^-4m·km^-2, 沿程曲率由正(下凹)-负(上凸)-正转变为负-正-负, 沿程河床也随之由淤积-冲刷-淤积趋势转变冲刷-淤积-冲刷趋势。     

企鹅珍珠贝耗氧率和排氨率的研究

采用室内实验生态学方法对企鹅珍珠贝的耗氧率和排氨率进行了研究。旨在为企鹅珍珠贝养殖容量(carrying capacity for aquaculture)的调查及育珠生理的研究提供参考,并可为海洋生态系统动力学和贝类能量学研究提供科学依据。研究结果表明,在实验温度(13~33℃)范围内,企鹅珍珠贝的耗氧率(OR)和排氨率(NR)与体重(W)都呈负相关,可分别表示为Y₁=a₁W-b₁和Y₂=a₂W-b₂,其中,a₁的取值范围是1.330~4.128,b₁的取值范围是0.453~0.651,a₂的取值范围是0.150~0.354,b₂的取值范围是0.446~0.634。在实验室温度(13~33℃)条件下,企鹅珍珠贝的耗氧率为0.329~7.303 mg/(g·h),排氨率为0.035~0.489 mg/(g·h),其中耗氧率在28℃时达到最高值,33℃时开始下降,而排氨率则呈持续升高趋势。企鹅珍珠贝呼吸和排泄Q₁₀值范围分别为0.210~2.494和1.193~2.483。在23~28℃温度范围内,不同规格企鹅珍珠贝的耗氧率和排氨率的比值(原子数O/N)较高。方差分析表明,体重、温度及二者的交互作用对企鹅珍珠贝的耗氧率和排氨率均有极显著的影响(P<0.01)。企鹅珍珠贝的日常代谢明显高于标准代谢,耗氧率和排氨率平均值分别提高32.1%和76.7%。