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1.
During June 1997 cruise by R/V Science No.l, observations on temporal and spatialvariations of the size-fractionated phytoplankton standing stock and primary production were carried out in the Bohai Sea. The size-fractionated chlorophyll a (Chl a) and primary production, photosynthet-ically available radiation (PAR), as well as the related physico-oceanographic and zooplanktonic parameters were measured at five time-series observation stations representing sub-areas of the sea. Results obtained show that there were the marked features of spatial zonation of Chl a and primary production in the Bohai Sea. The values in the Laizhou Bay, the Liaodong Gulf and the Bohai Gulf were high and showed close relation with tidal fluctuations, i.e. high Chl a concentration occurred during high tide in the Laizhou Bay, and during low tide in the Liaodong Gulf and the Bohai Gulf. In the strait and the central region of the Bohai Sea, the values were relatively low and no relationship with tidal fluctuation could be foun  相似文献   

2.
An attenuation depth is defined for remote sensing purposes as a depth above which 90% of the arising light leaving the water surface is originated.The deeper the attenuation depth,the more information of water is detectable by remote sensing,then the more precise information of water is extracted.Meanwhile,the attenuation depth is helpful to know water layer (by its thickness) from which remote sensing will be able to extract information.A number of investigators are using the moderate resolution imaging spectroradiometer (or MODIS) for remote sensing of ocean color.It is necessary to have a rough idea of the effective attenuation depth of imagery in each of the spectral bands employed by the MODIS.The attenuation depth is directly determined from MODIS data.Though analyzing the spectral distribution of the attenuation depth on 7 August 2003 and the seasonal variation of the attenuation depth (551 nm) in the Bohai Sea indicated that:the spectral distribution of the attenuation depth for the spectral range between 400 to 700 nm is single-peak curve,and it''s similar and difference in different regions is consistent with other scholars'' results of zoning,moreover,it supports the Bohai Sea is Case 2 water; the maximum attenuation depth shifts toward longer wavelengths,liking the red shift,with increase of turbidity of water,just like the maximum attenuation depth in the outside of the northwest coast of the Bohai Sea and the Bohai Strait is at 531nm,in the central of the Bohai Sea is at 551nm,in the region controlled by the Huanghe (Yellow) River,the region impacted by the old Huanghe River,the western side of the Liaodong Bay and the eastern side of the Liaodong Bay is at 555 nm; the seasonal change of the attenuation depth is the largest in the summer,followed by the fall,and the ranking of winter and spring in different regions is distinct.The attenuation depth in different regions is dissimilar:the order of the attenuation depth in different regions from small to big is the region controlled by the Huanghe River or the eastern side of the Liaodong Bay,the western side of the Liaodong Bay,the region impacted by the old Huanghe River,the central of the Bohai Sea or the outside of the northwest coast of the Bohai Sea,the Bohai Strait (except at 412 nm and 645 nm),in which between the region controlled by the Huanghe River and the eastern side of the Liaodong Bay (and between the central of the Bohai Sea and the outside of the northwest coast of the Bohai Sea) it varies in different seasons and different bands.  相似文献   

3.
During 1985~1987,the concentration of nitrate nitrogen was higher in the Laizhou Bay and the Bohai Bay while that of nitrite nitrogen was higher in the Liaodong Bay and the Bohai Bay,The concentration of nitrate nitrogen was highest in winter and lowest in summer while that of nitrite nitrogen was highest in autumn and lowest in spring .the seasonal variation of the concentration of nitrate nitrogen was maximum in the Laizhou Bay and the Bohai Bay while that of the concentration of nitrite nitrogen was maximum in the Liaodong Bay.There was a great difference in the concentration of nitrate nitrogen between the surface and the bottom in autumn and in the concentration of nitrite nitrogen between the surface and the bottom in summer.The main reason for the seasonal variations of the concentration of nitrate nitrogen and nitrite nitrogen was the marine biochemical process.The nitrate nitrogen and nitrite nitrogen in the Bohai Sea basically maintained a quasi-equilibrium state seasonal cycle,The quesi-equilibrium state seasonal cycle of nitrate nitrogen and nitrite nitrogen at the bottom was stable while that at the surface was liable to variations caused by other factors.  相似文献   

4.
渤海夏季环流的高分辨率海浪-潮汐-环流耦合模式研究   总被引:2,自引:0,他引:2  
The Bohai Sea is a shallow semi-enclosed inner sea with an average depth of 18 m and is located at the west of the northern Yellow Sea. The climatological circulation pattern in summer of the Bohai Sea is studied by using a wave-tide-circulation coupled model. The simulated temperature and the circulation agree with the observation well. The result shows that the circulation pattern of the Bohai Sea is jointly influenced by the tidal residual current, wind and baroclinic current. There exists an obvious density current along the temperature front from the west part of the Liaodong Bay to the offshore area of the Huanghe Estuary. In the Liaodong Bay there exists a clockwise gyre in the area north to the 40°N. While in the area south to the 40°N the circulation shows a two-gyre structure, the flow from the offshore area of the Huanghe Estuary to the Liaodong Bay splits into two branches in the area between 39°N and 40°N. The west branch turns into north-west and forms an anti-clockwise gyre with the south-westward density current off the west of the Liaodong Bay. The east branch turns to the east and forms a clockwise gyre with the flow along the east coast of the Liaodong Bay. The forming mechanism of the circulation is also discussed in this paper.  相似文献   

5.
A numerical method is designed to examine the response properties of real sea areas to open ocean forcing. The application of this method to modeling the China’s adjacent seas shows that the Bohai Sea has a highest peak response frequency(PRF) of 1.52 d-1; the northern Yellow Sea has a PRF of 1.69 d-1; the Gyeonggi Bay has a high amplitude gain plateau in the frequency band roughly from 1.7 to 2.7 d-1; the Yellow Sea(including the Gyeonggi Bay), the East China Sea shelf and the Taiwan Strait have a common high amplitude gain band with frequencies around 1.76 to 1.78 d-1 and are shown to be a system that responds to the open ocean forcing in favor of amplifying the waves with frequencies in this band; the Beibu Gulf, the Gulf of Thailand and the South China Sea deep basin have PRFs of 0.91, 1.01 and 0.98 d-1 respectively. In addition, the East China Sea has a Poincare mode PRF of 3.91 d-1. The PRFs of the Bohai Sea, the northern Yellow Sea, the Beibu Gulf and the South China Sea can be explained by a classical quarter(half for the Bohai Sea) wavelength resonance theory. The results show that further investigations are needed for the response dynamics of the Yellow Sea-East China Sea-Taiwan Strait system, the East China Sea Poincare mode, the Taiwan Strait, and the Gulf of Thailand.  相似文献   

6.
Predicted no-effect concentration(PNEC) is often used in ecological risk assessment to determine low-risk concentrations for chemicals. In the present study, the chronic data from native saltwater species were used to calculated PNEC values using four methods: log-normal distribution(ETX 2.0), log-triangle distribution(US EPA's water quality criteria procedure), burr III distribution(Burrli OZ) and traditional assessment factor(AF). The PNECs that were calculated using four methods ranged from 0.08 μg/L to 1.8 μg/L. Three of the SSD-derived PNECs range from 0.94 to 1.8 μg/L, about a factor of two apart. To demonstrate the use of SSD-based PNEC values and comprehensively estimate the regional ecological risk for cadmium in surface water of the Bohai Sea, in the Liaodong Bay, Bohai Bay, and Laizhou Bay, China, the dissolved cadmium concentrations were measured and obtained 753 valid data covering 190 stations from July 2006 to November 2007. Based on three ecological risk assessment approaches, namely hazard quotient(HQ), probabilistic risk quotient and joint probability curve(JPC), the potential ecological risk of cadmium in surface water of the Liaodong Bay, Bohai Bay, and Laizahou Bay were estimated. Overall, the ecological risk of cadmium to aquatic ecosystem in the whole Bohai Sea was at acceptable ecological risk level, the order of ecological risk was Liaodong BayBohai BayLaizhou Bay. However, more concerns should be paid to aquatic ecological risk in the Liaodong Bay which is the home of many steel, metallurgy and petrochemical industrial in China.  相似文献   

7.
Pseudopleuronectes yokamae (Günther) is one of the most important economic fish species in the genus living specially in the northwest Pacific, and is distributed in the southern area of the far east sea of Russia, Japan, Korea, the Huanghai Sea, the Bohai Sea and the northern area of the East China Sea. Usually they live in nearshore waters of these areas as geographic subpopulations. P. yokamae in the Sheath Bay belongs to a local group of the Huanghai-Bohai Sea subpopulation and is distributed in the mouth and adjacent waters of the bay all the year round, and the catch of its spawning group has  相似文献   

8.
Analyses of clay mineralogy about 30 surface sediments indicate widespread occurrence of illite, kaolinite, chlorite and montmorillonite throughout the Bohai Sea. Illite is the most abundant mineral, averaging 60%, kaolinite, next to illite, is the most abundant one,averaging 18%. Chlorite and montmorillonite come second, averaging 12% and 10% respectively. The distributive patterns of clay minerals in the surface sediments are closely related to the suspended materials carried into the Bohai Sea, especially to those did by the Huanghe River, and to water dynamics in the area. Based on the distribution, the assemblages and the others of clay minerals, the Bohai Sea can be divided into two clay mineral regions, the Liaodong Gulf region and the Bohai-Laizhou Bay region.  相似文献   

9.
The results of the suspended material measurement in the Huanghe River Estuary show that the silt movement in the estuary is different during summer and winter. The centric water-mass in Bohai Sea enters the Laizhou Bay, which makes the fresh water occupy the head of Laizhou Bay and prevents the silt from spveading to the sea.The disturbing of wind in winter makes the sediment resuspend which results in the high content of suspended materials in the water. The distribution of suspended materials and salinity in summer indicate that because of its own momentum, the silt from the Huanghe River will go ahead out of the river mouth and the effect of centric water-mass in the middle Bohai Sea is relatively small in summer. The distributions of suspended materials in the mid and bottom layer water during different seasons show that the primary direction of the siltl movement in the estuary is towards NE, whice coincides with the movement of residual current.Our paper also presents the size distribution of suspended materials.According to the data, we consider that the silt from Huanghe River moves mainly in the surface layer and the Huanghe River Estuary belongs to weak mixing estuary.  相似文献   

10.
-On the basis of the data obtained from the surveys in the Bohai Sea during 1982-1983, this paper analysed and discussed the distribution and seasonal variation of primary productivity in the Bohai Sea, and the correlations between the primary productivity and environmental factors. The organic carbon production and prospect of fishery production in the waters of this sea are estimated. It is shown that, there exists production patential in the Bohai Sea, the primary production is 112 gC/ (m2 ?a)the production of organic carbon being 10 million ton per year, the fishery yields 1 million ton and the maximum catch of sea products 0. 5 million ton. The results of the investigation can serve as the basic data for the exploitation, utilization and management of the fishery resources in the Bohai Sea.  相似文献   

11.
为研究莱州湾水交换对胶莱运河修建工程的响应,以及为海洋污染治理问题提供参考,以莱州湾为重点模拟区域建立了二维平面潮流和对流扩散模型,利用渤海、黄海、莱州湾地形及海洋环境资料,结合2018年莱州湾海水水质监测结果,初步分析了胶莱运河的修建对莱州湾海洋环境现状的影响。模拟结果表明,胶莱运河建成后年径流总量约为7.2×109 m3,净流方向由胶州湾流向莱州湾;工程后整个莱州湾水交换能力略有增强,东部强于西部,半交换周期缩短14 d;黄海海水经由胶州湾进入胶莱运河输送至莱州湾,冲淡莱州湾内非优良水体,从一定程度上缓解了莱州湾东部河口入海处小范围海域海水水质现状。  相似文献   

12.
The method has been established to calculate the environmental capacity (ECo),surplus environment capacity (SECo) of water with respect to marine petroleum hydrocarbons associated with oil (PHAOs) and the self-purification capacity (SPCo) of main self-purification process to PHAOs in the Jiaozhou Bay, China, according to the dynamic model for distribution of marine PHAOs among multiphase environments. The variation of concentration of PHAOs in the Jiaozhou Bay is well simulated by the dynamic model. Based on the model.the ECo, SECo of water with respect to PHAOs in the Jiaozhou Bay were calculated during the last 10 years under the first-class and second-class quality standard requirement, according to SPCoof main self-purification process to PHAOs. The results show that about 200 tons of PHAOs could be discharged into the Jiaozhou Bay for maintaining the first class seawater quality standard, and about 600 tons of PHAOs for the second class seawater quality standard later.  相似文献   

13.
利用14景环境与灾害监测预报星(HJ-1A/1B)CCD相机卫星数据,提取不同潮位下渤海海湾的水域面积.结合潮汐订正的方法,计算获得了2010年辽东湾、渤海湾和莱州湾的纳潮量分别为9.32x1010m3、3.03x1010m3和0.54×1010m3.计算结果将为渤海动力学研究提供参考.  相似文献   

14.
The distributions of chlorophyll a concentration, primary production and new productionwere observed in the Laizhou Bay of the Bohai Sea in both spring and neap tides during July 1997. The results showed that there were marked features of spatial zonation in the surveyed area, due to the differences between the geographic environment and the hydrological conditions. Chlorophyll a, primary production and new production were all higher in spring tides than that in neap tides in the Laizhou Bay. The highest values of these parameters were encountered in the central regions of the bay. At most stations, chlorophyll a concentrations at the bottom were higher than that at the surface. The results of size-fractionated chlorophyll a and primary production showed that contributions of nano-combining pi-coplankton ( > 20 μm) to total chlorophyll a and primary production were dominant in phytoplankton community biomass and production of the Laizhou Bay. The environmental factors, primary production and new product  相似文献   

15.
悬浮泥沙浓度(SSC)的变化对渤海海域的生态等有着重要的影响。本文基于已有表层水体SSC遥感反演算法进行了优化,利用较高时空分辨率的GOCI影像,基于优化后的模型对渤海表层水体的SSC浓度在半月潮周期中的时空分布与变化特征进行了研究。结果表明:(1)渤海各海湾表层水体SSC在半月潮周期内的变化规律存在差异。从小潮到大潮,辽东湾和渤海湾表层水体SSC先减小后增加,而莱州湾及黄河口附近海域的SSC则呈现出逐步降低的趋势。(2)渤海表层水体SSC存在明显的日内变化,且半月潮潮情对渤海SSC的变化作用显著。在一个连续潮周期中,除莱州湾和辽东湾外,渤海海域SSC的变化幅度总体上呈现出大潮时较大、平常潮次之、小潮时较小的特征。(3)渤海海域沿岸浅水区的SSC高于中部深水区,同时渤海海峡西北部脊沟区水体的SSC变化系数表现出与局部地形相似的辐射状的空间分布特征且与水深存在显著的负相关性,说明海底地形对SSC的空间变化具有不可忽略的影响。  相似文献   

16.
利用二维水动力数学模型模拟胶莱人工河道潮流运动,并分析了胶州湾湾口设置潜堤前后胶莱人工河道水质点的运动轨迹和水位变化过程。结果表明,开通胶莱人工河道能够使黄海的胶东湾海水向渤海的莱州湾输运,但不设置潜堤时从胶州湾到莱州湾的海水输运平均流速较小;设置潜堤后胶州湾水位高于莱州湾水位的时间变长,从黄海到渤海之间的水体输运能够得到加速。计算结果还表明,潜堤顶部与平均水面距离较小时,黄、渤海之间水体输运较快。  相似文献   

17.
This study provides new insights for the hatchery released Chinese shrimp (Fenneropenaeus chinensis), including proportion, dynamic migration route, after they were released into nature for stock enhancement using a new strategy quite different than ever. Chinese shrimp were sampled at 22 survey stations during two investigation voyages acrossing 74 survey stations in the Bohai Sea from July 16 to August 9 in 2015. Among 289 sampled individuals during the second voyage, totally 155 shrimps were identified as hatchery shrimp released into the Laizhou Bay at mid-May in 2015 based on finger-print of eight SSR (simple sequence repeats) markers, and the proportion of hatchery released shrimp in recapture samples were from 41.30%–85.71% in each station with an average value 53.63%, which verified a previous view point that up to 90% of autumn season Chinese shrimp landing in the Bohai Sea were composed of hatchery released. Meanwhile, the dynamic migration route of hatchery released shrimp revealed that part of released shrimp migrated heading northwest along the west coast of the Bohai Sea up to the Bohai Bay but just remained at the Laizhou Bay until over-wintering migration at mid-October when they initiate over-wintering migration. Present unnatural spring season shrimp fishing model cut the throat of spawner shrimp chance to swim back to their respective spawning plants at each spring, it still no chance to clarify whether the hatchery released shrimp could replenish to the reproduce population and complete a whole life cycle as same as their natural relatives.  相似文献   

18.
渤海海区COD分布及对海水富营养化贡献分析   总被引:9,自引:0,他引:9  
于2002年8月10~18日和2003年8月12~28日对渤海海区进行了海水水质调查。结果表明,调查海域化学耗氧量(COD)平均浓度分别为0.70 mg/L±0.21 mg/L和0.63 mg/L±0.18 mg/L,其中相对高值区(>1 mg/L)主要分布在辽东湾北部,莱州湾南部和中央海区西北部海域,而相对低值区(<0.6 mg/L)主要分布在中央海区东南部。分析表明,调查海域COD浓度不仅远远低于国家一类海水水质标准,而且也大大低于渤海沿岸水。进一步分析表明,COD对于调查海域富营养化的贡献仅为1/4左右,这一结果证明了造成渤海海区富营养化的化学污染物不是COD。  相似文献   

19.
1999年渤海浮游植物生物量的数值模拟   总被引:6,自引:1,他引:6  
以浮游植物量、浮游动物量、营养盐浓度 (包括无机氮和无机磷 )以及碎屑量为生态变量 ,在HAMSOM水动力学模式的基础上构建了 1个三维浮游生态动力学NPZD模型。采用此模型研究了渤海 1999年浮游植物量和初级生产力的变化情况 ,模拟结果与实测基本相符。模拟结果表明 :1999年渤海浮游植物量的变化大致呈双峰分布 ,春季水华出现在4,5月份 ,秋季水华出现在 9,10月份 ;受透明度和局地水深的影响 ,渤海湾和辽东湾北部浮游植物量的年变化呈夏季大、冬季小的单峰分布。 1999年渤海不同海区初级生产力的变化特征是 :除莱州湾一年中有春、夏 2个峰值外 ,其它 3个海区都是夏季高、冬季低的单峰分布 ;1999年整个渤海年平均的初级生产力为 2 5 7mgC/m2 /d。  相似文献   

20.
渤海沉积物重金属环境质量评价及其影响因素   总被引:1,自引:0,他引:1  
基于渤海404个站位的沉积物重金属元素含量与分布特征,通过潜在生态风险、地累积指数等指标定量评价了沉积物中重金属的环境质量,利用富集因子和主成分分析法,对影响渤海表层沉积物中重金属元素分布特征的影响因素进行了分析。研究结果显示,渤海湾重金属元素平均含量最高,渤海海峡最低;渤海Cd具有强潜在生态风险,Hg具有中等?强潜在生态风险,总潜在生态风险程度为中等;Cr和Ni的少量站位超过毒性阈值上限,其余重金属污染物含量均低于毒性阈值下限,表明渤海发生沉积物重金属的毒性污染的概率很低。沉积物中粒度效应控制的重金属元素含量对渤海表层沉积物中的重金属元素的分布具有主要影响,人类活动所造成的污染主要是Cd,主要分布于辽东湾的锦州湾和复州湾,其次通过河流进入海洋的Hg对黄河三角洲及莱州湾有重要影响,亟需引起注意。  相似文献   

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