2018年6月渤海大型水母分布特征

2018年6月使用渔业底拖网采样,对渤海大型水母进行了全面调查,调查船舶为"中渔科102"渔业科考船。本研究分析了渤海大型水母的种类组成、渔获密度与伞径大小,并对其源地进行了探讨。结果表明:本次调查共采集到海月水母、沙海蜇、海蜇、多管水母四种大型水母,其中海蜇、多管水母数量较少,各采集到一只。海月水母在渤海三湾均有分布,各海区伞径大小无显著差异且多为幼体(<10cm),密度高值区出现在渤海湾东南侧海域,可达38—221.21ind./(net·h),辽东湾海月水母出现于湾南,密度<5ind./(net·h),湾北未见;作者推测,海月水母在渤海沿岸可能存在多个源头,诸如:莱州湾与渤海湾交界近岸海域、河北近岸、辽东湾大连近岸以及北部近岸。沙海蜇在渤海分布较广,辽东湾为密度高值区,均值为(35.32±21.64)ind./(net·h),但伞径较小,均值为(12.15±6.52)cm;与此相对,渤海湾与莱州湾外侧海域沙海蜇密度虽小[<20ind./(net·h)],但伞径要显著大于辽东湾,最大伞径均值可达(33.86±7.40)cm;作者推测,沙海蜇在渤海海域发源地主要集中...     

氮形态组成对海洋浮游植物群落结构的影响与动力学研究

海洋浮游植物群落结构的改变与营养盐结构有关,不同形态氮可能会影响优势种生长从而改变浮游植物群落结构.本文针对莱州湾硅藻向甲藻潜在的种群演替问题,通过船基围隔生态系现场氮加富培养实验,研究NO3-N、NH4-N、陆源有机氮(DONts)和藻源有机氮(DONss)对海洋浮游植物群落结构的影响.结果表明,在NO3-N、NH4...     

胶东半岛南部典型海湾地貌过程对滩涂养殖的响应

应用3S技术和海湾涨/落潮不对称原理,研究了最近40年来胶东半岛南部四个典型潮汐汊道海湾的动力地貌演变,分析了大面积修建养殖池对海湾地貌过程的影响。结果表明,最近30年来4个海湾的海岸地貌类型面积、空间分布格局、地貌类型转换、地貌结构和地貌冲淤状态发生了显著改变。在大面积养殖池被围建以前的1960s年代末到1980s年代初,丁字湾处于涨潮不对称状态但不对称程度增高,乳山湾、五垒岛湾和靖海湾也处于涨潮不对称状态但不对称程度在降低。最近30年来的大面积滩涂养殖池修建,使丁字湾由不断增强的涨潮不对称向落潮不对称状态逆转,使五垒岛湾、靖海湾由涨潮不对称向落潮不对称状态的转化提前,使乳山湾由涨潮不对称向落潮不对称状态的转化延缓。     

Utility of clay Minerals in the Determination of Sedimentary Transport Patterns in the Bay of Cadiz and the Adjoining Continental Shelf (SW-Spain)

The contents and the distribution of clay minerals in modern sediments of the Cadiz bay and the continental shelf have been studied aiming to establish the sedimentary exchange model and the pathways followed by the clay fraction between the bay and the adjoining continental shelf. The most abundant clay minerals in the muddy sediments consist mainly of illite, smectite, interstratified illite-smectite, kaolinite and chlorite. The application of factor analysis method (PCA) to clay minerals data are considered to be useful in the determination of sedimentary transport patterns. The data from clay mineral assemblages, and their distribution map, make possible to establish the fine sediments transport paths in the study area using clay mineral as natural tracers. This model of transport takes in consideration the facies distribution, the supplies sources and the way of fine sediments are incorporated to the marine environment.

Two flows paths have been established: the outflows coming from Cadiz bay and the littoral zones; and the inflows coming from external marine zones of the bay. These flows are controlled by tidal currents and the morphology of the coast. The action of surge and the marine currents, specially the Atlantic Surface Water flow, are also important in the transport of fine sediments coming from sources located to the north of the study zone.     

1980—2020年大湾区海岸线变迁及影响因素分析

海岸线动态变化是全球变化和人类活动共同的反映。本文基于粤港澳大湾区、东京湾和旧金山湾1980—2020年7期Landsat系列遥感影像及Google Earth高分辨率影像, 利用阈值分割, 结合水体指数法、Sobel算子法, 提取各期海岸线。从长度、空间形态、结构和利用程度等多角度分析其岸线变化, 并结合地理探测器对其影响因素进行定性和定量分析。结果显示: 1) 1980—2020年间, 各湾区岸线趋于平直, 其中东京湾海岸线的年均长度变化强度最大, 为0.37%; 2) 40a间各湾区岸线的纵深变化比较稳定, 结构趋于复杂, 形态趋于分散, 其中粤港澳大湾区海岸线的分维差异最小, 形态最分散; 3) 40a间, 各湾区的自然岸线减少, 港口码头岸线和其他人工岸线长度剧烈增长, 其中粤港澳大湾区的生物岸线波动增长, 岸线利用程度指数增幅最大。本文研究结果表明, 气温、波高、潮汐和陆域面积、港口吞吐量是湾区海岸线变化的主要影响因素, 且任意两个影响因素的交互作用大于单一因素的作用。     

Hydrochemical characteristics and salinization processes of groundwater in the shallow aquifer of Eastern Laizhou Bay,China

Groundwater salinization has become a crucial environmental problem worldwide and is considered the most widespread form of groundwater contamination in the coastal zone. In this study, a hydrochemical investigation was conducted in the eastern coastal shallow aquifer of Laizhou Bay to identify the hydrochemical characteristics and the salinity of groundwater using ionic ratios, deficit or excess of each ions, saturation indices and factor analysis. The results indicate that groundwater in the study area showed wide ranges and high standard deviations for most of hydrochemical parameters and can be classified into two hydrochemical facies, Ca²⁺‐Mg²⁺‐Cl^‐ facies and Na⁺‐Cl^‐ facies. The ionic ratio, deficit or excess of each ions and SI were applied to evaluate hydrochemical processes. The results obtained indicate that the salinization processes in the coastal zones were inverse cation exchange, dissolution of calcite and dolomite, and intensive agricultural practices. Factor analysis shows that three factors were determined (Factor 1: TDS, EC, Cl^‐, Mg²⁺, Na⁺, K⁺, Ca²⁺ and SO₄^2‐; Factor 2: HCO₃^‐ and pH; Factor 3: NO₃^‐ and pH), representing the signature of seawater intrusion in the coastal zone, weathering of water–soil/rock interaction, and nitrate contamination, respectively. Copyright © 2011 John Wiley & Sons, Ltd.     

最近50a来莱州湾西—南部潮流动力演变的数值模拟研究

根据1959、1984、2002年测量的海图,基于二维浅水方程分别构建了3个年份的莱州湾潮流场模型,研究了最近50a来莱州湾西—南部潮流动力演变规律,揭示黄河河口沙嘴形成演变对莱州湾西—南部潮流动力的影响。结果表明,最近50a中在沙嘴外围一直存在弧形高流速带,在弧形高流速带外围又有潮流剪切锋,潮流剪切锋包括内涨外退式和内退外涨式两类。随着河口沙嘴的不断向海延伸,莱州湾西—南海域的等潮位线呈以沙嘴为中心的辐射式格局;弧形高流速带整体向外海移动,其范围和流速也随之不断增大;剪切锋历时变长、间隔时间变短、南北跨度变大;但弧形高流速带和潮流剪切锋始终位于青坨子以北海域。对照同期海岸地貌演变,在弧形高流速带、潮流剪切锋等共同作用下,大部分黄河入海泥沙的输运路径和沉降范围仅限于青坨子以北,导致海岸地貌以此为界呈现显著的差异性演化。     

广东流沙湾近岸和离岸育珠海区养殖环境的调查

2011年2月~2012年1月对广东流沙湾近岸和离岸育珠海区6个航次11个指标进行了调查。结果表明,近岸和离岸育珠海区水温、透明度、盐度和pH周年变化范围相似,水温呈现明显季节性变化,透明度、盐度和pH周年比较稳定,揭示目前流沙湾近岸和离岸育珠海区水流交换较好。近岸和离岸育珠海区叶绿素a和浮游植物细胞密度具有类似的周年变化规律,夏秋季高于冬春季。在4~7月份和9~10月份,近岸海区叶绿素a和浮游植物细胞密度呈现显著递增趋势,而10月份之后,显著递减。2~4月份,以及12月份至次年1月份,叶绿素a值和浮游植物细胞密度均较低。5~11月份,离岸海区叶绿素a和浮游植物细胞密度均显著低于近岸海区。近岸和离岸育珠海区COD含量周年变化范围分别为0.2~0.7 mg/L和0.1~0.8 mg/L,均达到国家一类水质标准。近岸海区和离岸海区无机氮(inorganic nitrogen,IN)含量周年变化范围分别为1.9~8.0μmol/L和3.4~8.7μmol/L,均达到国家第二类水质标准。两个海区IN含量的周年变化趋势与叶绿素a值和浮游植物细胞密度的周年变化趋势相反,冬春季高于夏秋季。无机磷(inorganic phosphorus,IP)在流沙湾近岸和离岸海区含量具有相似的周年变化趋势,其季节性变化与无机氮恰好相反,表现为夏、秋季含量高于冬、春季。6~8月份,近岸海区IP超出国家二类水质标准分别达44.67%、96.33%和210%,离岸海区在相同的月份超出国家二类标准分别达75.67%、86%和230.67%。揭示在夏、秋季节应合理控制贝类养殖密度和流沙湾周边环境的污染。     

渤海南部Lz908孔海陆交互沉积的粒度特征及其对沉积环境的指示

文章对采自莱州湾南岸的钻孔沉积物样品进行了粒度测试和分析。样品平均粒径介于3.3-6.8?,以极细砂和粗粉砂为主,含有少量的粘土质;分选较差;偏度表现为正偏和极正偏;沉积物粒度表现为正态、正态—尖锐和尖锐,少数表现为平坦和极尖锐。粒度象指示了历史时期持续高的初始沉积水动能和多种沉积环境的变化,粒度参数散点图反映了多种动能影响了沉积物的沉积改造,综合判别分析对沉积环境的限定,得到了莱州湾南岸沉积物受到河水径流、潮流、波浪等共同作用形成。沉积物总体反映了莱州湾南岸长时期处于河流相和三角洲相的沉积环境,少数较细的粒度表现可能与研究区的多期海侵过程相对应。     

Yield trait improvement of bay scallops following complete diallel crosses between different scallop stocks

This study describes the complete diaUel hybridization between newly introduced bay scallop stock （W） from Canada and local commercial stock （D） grown under laboratory conditions, in China. Larval survival and growth during all life stages （larvae, spat, and adult） were compared among hybrid （DW, WD） and purebred （DD, WW） populations. Significant heterosis was detected for survival during the larval stage （〉 1% of the mid-parent values）. The mean heterosis （Hm） varied in growth throughout the life span. More than 50% of the Hm values were positive and negative in the DW and WD groups, respectively. The influence of maternal effects and mating types （intrapopulation vs. interpopulation crosses） on growth for all life stages was not consistent. Larval survival did not differ significantly （P〉0.05） with maternal effect or mating type. In the harvest stage, shell length （SL）, shell height （SH）, shell width （SW）, and total weight （TW） were larger in the hybrid compared with the inbred groups. Positive Hm values were observed in SL （1.5%）, SW （5.8%）, and TW （12.3%）, and were more significant in the DW groups （6.1%, 4.5%, 6.8%, and 27.2%）. These results suggest that hybridization between two geographic populations is a good tool for improving bay scallop growth. However, unstable heterosis between the two populations requires further study.