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1.
大亚湾温跃层形成及其对有关环境要素的影响 总被引：4，自引：0，他引：4
温跃层是海洋环境中的一种重要物理现象,对海洋的环境生态系统有着重要的影响。大亚湾温跃层是受粤东上升流和夏季表层海水升温双重作用而形成的。通过对大亚湾海域水温、盐度、溶解氧等众多环境要素的长期调查取样分析显示,该海域温跃层是季节性温跃层,一般发生在每年的5—10月份,6月下旬到9月中旬分层现象比较显著,盐跃层和氧跃层会相伴发生。受核电站热排水的影响,湾西侧尤其是核电站前海域的温跃层较其它区域明显和持久。数据显示在温跃层发生期内,由于海水的分层效应,温度、盐度、pH值、DO、BOD5和COD、营养盐及叶绿素等都受到不同程度的影响,形成明显的表底层差异或层次梯度。 相似文献
2.
根据南黄海断面1977—2016年历年8月标准层温度、盐度与气候要素观测资料,采用时空分析等方法,分析了南黄海断面夏季温度、盐度年际时空变化与气候响应。断面温度主要有4种时空模态,夏季风生环流、冷水团强度、面积与断面冬季温度模态是主要温度模态年际变化的主要影响因素;夏季风生流场形态、春季PDO指数与断面冬季温度模态是次要温度模态年际变化的主要影响因素;温度模态时间分量均为准平衡态长期变化。断面盐度主要有4种时空模态,夏季苏北沿海低盐度水体、南黄海中部高盐度水体与夏季黄海风生流输送作用是盐度主要模态年际变化的主要影响因素;夏季南黄海降水量减少与风生流输送减弱是盐度次要模态年际变化的主要影响因素。盐度主要模态时间分量为准平衡态长期变化,次要模态时间分量存在显著线性低盐趋势变化。断面夏季温盐多年平均分布主要受到夏季多年平均风生环流影响。断面核心冷水团月平均温度为准平衡态长期变化;面积存在显著线性减小趋势,黄海风生流场季节与年际变化是南黄海核心冷水团年际变化主要影响因素,春季PDO指数对冷水团面积年际变化有显著非线性影响。断面冷水团、核心冷水团月平均盐度为显著线性低盐趋势周期年际变化。由于黄海温盐长期线性趋势变化,与30多年前状况相比,目前黄海温盐场季节循环时空变化形态可能已经发生显著改变。 相似文献
3.
作者对秦山核电站邻近水域进行了春、夏、秋、冬(1989年4月～1990年1月)四个航次的综合调查。结果表明,该区域大型底栖动物的生物量和个体数量极为贫瘠(分别为0.03g/m~2和2.0个/m~2),生物种类组成简单,经鉴定有33个种类,并有明显的季节变化。底栖动物群落结构表现出鲜明的河口或近岸性广温低盐的生态特点。属杭州湾的白虾—长臂虾群落,夏季棘头梅童鱼Collichthys lucidus占绝对优势。水动力因子、沉积作用和盐度是决定调查区域底栖动物种类、数量和分布的关键因子,而季节变化则主要受温度所控制。 相似文献
4.
Hidetaka Takeoka 《Journal of Oceanography》1987,43(1):21-27
The average residence time and the remnant function which are quantitative expressions of water exchange in coastal waters are investigated in a timevarying transport field by using a simple model. It is shown that the influence of temporal variation on the average residence time and concentration is small, when the ratio of the period of variation to the average residence time in the average state is small, and the influence is large when the ratio is large. The results are applied to the Seto Inland Sea, Lake Hamana, and Osaka Bay. 相似文献
5.
利用2017年1?12月的现场观测数据,分析了湛江湾温盐的三维空间结构及季节变化特征。结果表明:(1) 2017年湛江湾各站位年平均温度为23～27℃、盐度为19～27、位势密度为11～17 kg/m3、浮性频率(N2)为7×10?5～5×10?3 s?2。浮性频率的垂向结构及水平分布与温度分布类似,而位势密度则与盐度的变化趋势几乎一致;(2)温度季节变化明显,夏季最高,秋季次之,冬季最低,冬夏温差最大达15℃,而盐度季节变化则不大。相较于季节引起的变化,涨落潮对温度以及盐度影响较小。温度跃层夏季最强,10 m处温度最大梯度可达到0.7℃/m,春秋季温跃层抬升至5 m附近,冬季水体上下混合均匀。夏季和秋季存在明显的盐跃层,盐度梯度最大可达到1.1 m?1。跃层上下温盐的季节变化规律一致;(3)水平分布上,从湾顶区、湾颈区、大堤区、浅滩区到湾口区,温度递减,盐度递增,湾顶区和湾口区平均温度差为2.3℃,盐度差为2.7。温盐图分析显示,不同季节水体呈现为不同的温盐条带,湾口区基本为低温、高盐水体,而湾顶区基本为高温、低盐水体,其他区域水体介于上述两者之间。 相似文献
6.
山东半岛沿岸海域陆海相互作用强烈,有着复杂水动力环境的同时也是我国重要的渔业资源区和水产养殖区,针对其DO时空变化特征及影响机制的研究具有重要意义。本文基于2015—2017年期间的监测数据,研究了山东半岛东部近海海水溶解氧的时空变化特征,并结合实测的温度、盐度、pH数据探究其影响机制。结果表明：表、底层溶解氧的空间分布形态基本一致,水平上呈现出北高南低、外海高近岸低、湾内低于湾外的块状分布特点,垂向上表层高于底层。在监测期间内,溶解氧的季节变化规律为春季最高,夏季最低,具体表现为3月>5月>10月>8月,乳山湾等海湾处的季节波动较大;表底层溶解氧的年际变化略有不同,但均趋于稳定,靖海湾和五垒岛湾近海溶解氧的年际变化显著。表观耗氧量在整个研究阶段的均值为–0.33 mg/L,呈现出基本平衡状态,但乳山湾沿岸海域受到陆源输入有机物的显著影响,贫氧状况频发。监测期间,溶解氧与海水温度呈显著负相关,两者相关系数高达–0.95,其中成山头至石岛海域的溶解氧浓度高值区与当地的低温海水相对应;盐度对溶解氧的影响则相对较弱;有机污染物的聚集常造成乳山湾近岸海域的pH异常,其大量耗氧是导致当地为溶解氧浓度低值区的重要原因。 相似文献
7.
K M Azam Chowdhury Wensheng Jiang Guimei Liu Md Kawser Ahmed Shaila Akhter 《海洋学报(英文版)》2022,41(4):23-39
In the northern Bay of Bengal, the existence of intense temperature inversion during winter is a widely accepted phenomenon. However, occurrences of temperature inversion during other seasons and the spatial distribution within and adjacent to the Bay of Bengal are not well understood. In this study, a higher resolution spatiotemporal variation of temperature inversion and its mechanisms are examined with mixed layer heat and salt budget analysis utilizing long-term Argo（2004 to 2020） and RAMA（2... 相似文献
8.
9.
Physical oceanographic data were collected during September 1975 at stations in the shallow water (max. depth 45 m) embayments of Salonica Bay and Thermaicos Gulf, and comparisons are made with data collected during other seasons. The distribution of temperature and salinity in the water column indicated the following features: fresh surface water predominantly related to river discharge; an intermediate water mass, apparently formed by mixing between the fresh and open sea waters; a thermocline, and deep bottom water open sea characteristics. The summer distribution of density in the surface and bottom waters, and the seasonal variation in the pattern of surface salinity, suggested an anti-clockwise water circulation throughout the embayments. 相似文献
10.
基于ECCO2 (Estimating the Circulation and Climate of the Ocean)、 GLORYS12V1 (Global Ocean Reanalysis and Simulations)、ORA-S5 (Ocean ReAnalysis)三种海洋再分析数据,对比研究了菲律宾海盆深层温盐及环流的季节和年际变化特征。结果表明:三种数据显示的海盆深层温盐季节变化特征基本一致,在3 000～4 000 m水深区域,海水呈春夏两季高温低盐而秋冬季低温高盐特性,4 000 m以下海水温盐季节变化很小;沿西边界,温度与内部有明显差异且季节变化幅度相对较大。沿西边界的输运季节变化特征表现为10月至次年4月输运向南,5—9月输运向北,并且在8月份达最大值;表明存在沿西边界的流动,即菲律宾海盆与南端西卡罗林海盆(West Caroline Basin)之间存在季节性水体交换。海盆深层海水温盐年际变化也十分显著,但不同数据显示的变化特征存在较大差异。EOF和相关分析显示,三种再分析数据的深层位温与ENSO均存在一定相关性,ECCO2的深层位温变化与ENSO的相关性最强。由于长期观测数据较少,再分析数据的结果难以验证,因此目前对年际变化特征的研究仍具有很大的不确定性。 相似文献
11.
北部湾东北部水团分布及季节变化分析 总被引：2，自引：0，他引：2
基于2016年9月—2017年8月北部湾海域棕囊藻调查9个航次的温度、盐度和密度等水文数据,通过K-mean动态聚类分析方法分析了研究海域水团的分布及季节变化过程。根据温盐资料将研究海域的海水类型分为低温高盐的陆架底层水团、陆架表层混合水团和低盐沿岸水团。通过20°10′N断面上多期次的温盐分布特征揭示了北部湾整体上逆时针环流在北部湾东侧陆坡的存在;通过大面水文调查的结果揭示琼州海峡的余流特征,并结合卫星漂流浮标运动轨迹揭示了珠江冲淡水对研究海区水团分布的影响。本研究丰富了对北部湾东北部水团分布和季节变化的认知,对研究该海域赤潮发生、发展规律有指导意义。 相似文献
12.
厦门三个重要养殖水域浮游动物的数量分布特征 总被引：6，自引：0，他引：6
本文主要研究2000年厦门3个重要养殖水域浮游动物的种类组成和数量分布特征,并就其与环境因子的关系进行了初步探讨.结果表明,在这3个重要养殖水域共记录到浮游动物102种及16种浮游幼虫,以近岸、河口低盐种类为主.种类数的季节分布与水温的季节变化一致浮游动物生物量、个体数量与叶绿素a含量、浮游植物细胞数呈显著的二次抛物线关系.受地理环境和海水盐度影响,浮游动物的分布具明显的差异,数量一般呈马銮湾>厦门西港>同安湾(含东咀港和浔江港).浮游动物数量季节分布呈现春季高,冬、夏季居中,秋季最低的特点,除受水温等因子影响外,也与养殖贝类的数量密切相关. 相似文献
13.
SHEN Yongming 《中国海洋工程》2000,14(4):447-458
The prediction of water temperature and salinity in coastal areas is one of the essential tasksin water quality control and management.This paper takes a refined forecasting model of water tempera-ture and salinity in coastal areas as a basic target.Based on the Navier-Stokes equation and κ-ε turbu-lence model,taking the characteristics of coastal areas into account,a refined model for water temperatureand salinity in coastal areas has been developed to simulate the seasonal variations of water temperatureand salinity fields in the Hakata Bay,Japan.The model takes into account the effects of a variety ofhydrodynamic and meteorological factors on water temperature and salinity.It predicts daily fluctuationsin water temperature and salinity at different depths throughout the year.The model has been calibratedwell against the data set of historical water temperature and salinity observations in the Hakata Bay,Japan. 相似文献
14.
根据2018年1月冬季航次的水文实测资料,详细分析了大亚湾海水温度(T)、盐度(S)的分布特征。整体而言,观测海区海表相对于海底具有高温低盐的特征;同时,无论是表层还是近底层,大亚湾湾内的海水相对于湾外都呈现高温低盐的特征。观测期间,应是受到大亚湾核电站温排水的影响,湾内西侧存在一个高温中心。盐度的差异在近底层更加明显,低盐中心位于大亚湾的湾顶和大亚湾的中部海域,而高盐中心则主要分布于湾口西侧及惠东以东附近海域。太阳辐射和潮流变化是影响大亚湾温度、盐度变化的两大重要因素。其中,太阳辐射的影响主要局限于表层3~4 m,对近底层海水的影响较小;其加热效应使湾内和湾口附近的表层海水都表现出明显的昼夜变化。由潮汐和温度、盐度的对应关系可知,潮流对湾内温度、盐度的影响较大,而对湾外温度、盐度的影响较小。 相似文献
15.
乐清湾海域浮游动物群落分布的季节变化特征及其环境影响因子 总被引：3，自引：0，他引：3
2006年10月、2007年1月、4月及7月对乐清湾海域浮游动物群落的种类组成、优势种、生态类群、水平分布的季节性变化特征进行了调查,分析了浮游动物群落分布与环境因子的关系。结果表明,在调查海域共鉴定出浮游动物82种(包括浮游幼体11种),隶属于15大类,其中秋季为46种、夏季为42种、春季为25种和冬季为16种。乐清湾浮游动物可分为近岸低盐类群、暖水性近海类群、暖温带近海类群和暖水性广布类群4个生态类群,其中近岸低盐类群在全年均占优势,其它类群则呈现明显的季节变化。中华哲水蚤Calanus sinicus、真刺唇角水蚤Labidocera euchaeta、针刺拟哲水蚤Paracalanus aculeatus和背针胸刺水蚤Centropages dorsispinatus为调查海域主要优势种。浮游动物生物量年平均值为82.7mg/m3,其大小依序为:夏季(121.1mg/m3)>秋季(119.2mg/m3)>春季(48.5mg/m3)>冬季(42.2mg/m3);丰度年平均值为82.1个/m3,其大小依序为:夏季(193.4个/m3)>秋季(73.7个/m3)>春季(53.4个/m3)>冬季(9.8个/m3)。相同季节浮游动物生物量和丰度的平面分布趋势类似,季节间则存在明显差异。相关性分析结果表明,浮游动物物种数与水温、盐度、叶绿素a质量浓度和浮游植物细胞密度均呈极显著相关;丰度与水温、叶绿素a质量浓度和浮游植物细胞密度呈极显著相关;生物量与水温、叶绿素a质量浓度呈极显著相关。与历史资料相比,近30a来浮游动物数量呈下降趋势,但群落结构和组成没有发生明显改变。 相似文献
16.
热带印度洋降水、蒸发的时空特征及其对海表盐度的影响 总被引：3，自引：2，他引：1
本文利用降水、蒸发等资料分析热带印度洋年降水量、蒸发量、净淡水通量的分布特征，并选取4个典型海域来分析降水量、蒸发量、净淡水通量的季节变化和年际变化。结果表明:东印度洋的苏门答腊岛西部海域年降水量最大，季节变化较小，属全年降雨型；孟加拉湾的东北部和安达曼海的北部海域年降水量较大，其年际变化以4.2 mm/a的速率增长，强降水出现在5-9月；阿拉伯海的西部海域年降水量较小；南印度洋东部（20°~30°S，80°~110°E）海域年降水量较小，年蒸发量较大，年蒸发量在2000年之前以5.1 mm/a的速率增长，之后以4.5 mm/a的速率减小。本文还采用Argo盐度等资料探讨降水、蒸发对海表盐度的影响，研究结果表明:降水量远大于蒸发量的海域，海表盐度较低；降水量远小于蒸发量的海域，海表盐度较高。表层水平环流是导致高净淡水通量中心与低盐中心并不重合的主要原因，也是导致强蒸发中心与高盐中心并不重合的主要原因。选取的4个典型海域海表盐度的季节变化与净淡水通量关系不大，而是与表层水平环流有关。孟加拉湾强降水对表层盐度的影响显著，强降水发生后表层盐度降低0.2~0.8，其影响深度为30~50 m。 相似文献
17.
普里兹湾水文特征与变化 总被引：2，自引：1，他引：2
根据澳大利亚学者分别在１９８２年１２月和１９８７年２月普里兹湾的调查资料,并结合中国＂极地＂号南极考察船１９９０～１９９１年间的调查资料印证,提出在中国＂中山站＂所在地普里兹湾在初夏与晚夏期间的水文特征。 相似文献
18.
《Oceanologica Acta》1998,21(2):179-190
The annual cycle of temperature, salinity and nutrients of surface waters (up to 100 m depth) was studied from June 1991 to December 1995 in a cross-shelf section over the continental shelf waters off Santander (southern Bay of Biscay). The time series showed that the temperature followed the expected seasonal warming and cooling pattern, which determines a seasonal process of stratification and mixing of the water column. The stratification period occurs annually between May and October in a layer of about 50 m depth from the neritic station beyond to the shelf-break. In the period between November and April the water column remained mixed. During spring and summer low salinity values were found in the surface due to continental runoff and advection from oceanic waters. In late autumn and winter, the salinity pattern was governed by an influx of salty water associated with the poleward current. As in other temperate latitudes, nitrates showed the highest values in winter throughout the water column and the lowest values at the surface during the stratified period. Wind-induced upwelling events were observed mainly in summer, which are characterised by low temperatures (< 12°C), high salinity and nutrient concentrations. The inter-annual variability of temperature showed a warming trend in the upper layers but this sign was not found at 100 m depth. In salinity a decreasing trend was observed throughout the water column, and this feature corresponds to the relaxing of the high salinity anomaly detected in the North Atlantic at the beginning of the 1990s. Both trends were coherent in the cross-shelf section from the coast to the slope. 相似文献
19.
Long-term variability of shelf water intrusion and its influence on hydrographic and biogeochemical properties of the Seto Inland Sea, Japan 总被引：1，自引：0，他引：1
The variability of the pathway of the Kuroshio is known to control that of the intensity of upwelling of the cold and nutrient-rich
deep shelf water at the shelf-break point. This study has investigated the influences of the long-term variability of the
hydrographical and biogeochemical conditions at the shelf-break point on those in the inner Seto Inland Sea. Results from
observations conducted since 1972 by prefectural fisheries observatories showed a temporary decrease of temperature in the
lower layer of the entrance of Kii Channel in summertime in the specific years when the Kuroshio pathway favored deep shelf
water intrusion. A corresponding change in temperature was also found in the inner shelf sea, such as western Osaka Bay and
Harima-Nada. The model developed in this study covers a 30-year period and well reproduces the temporal change in temperature.
It also shows sufficient reproducibility in both seasonal behavior of hydrographical and biogeochemical properties and the
inter-annual variability of hydrographical properties throughout the eastern Seto Inland Sea. It was found that the inter-annual
variations of annual total flux through the section at the entrance to Kii Channel affect the inter-annual variation of the
observed concentration of Dissolved Inorganic Nitrogen (DIN) in Harima Nada, but the effect was smaller than those of river
input and other parameters. 相似文献
20.
Tomogashima Strait, which is an entrance of Osaka Bay, is a very important area for material transport because a large volume of pollutant-rich water in Osaka Bay is transported through this strait. We have investigated the cross sectional structures of current and material fluxes at Tomogashima Strait, Osaka Bay. Tidal current and residual flow patterns in cross section at Tomogashima Strait during summer and winter are almost the same, and residual flow in summer is stronger than that in winter. However, the net water exchange through the strait in summer was almost the same volume as that in winter. At Tomogashima Strait, total suspended matter (TSM) and particulate organic carbon (POC), and individual nitrogen and phosphorus compartments in Osaka Bay always flowed out except particulate organic nitrogen (PON). The average outflows of total nitrogen (TN) and total phosphorus (TP) at Tomogashima Strait over a year were calculated to be 145 ton/d and 30 ton/d, respectively. The average outflow of DIN and DIP at Tomogashima Strait over a year were 95 ton/d and 13 ton/d (DIN/DIP = 16), respectively. Residence times of both DIN and DIP in Osaka Bay were estimated to be about two months. 相似文献