莆田市平海湾海水养殖区表层沉积物重金属生态危害程度和水环境问题分析

为了研究莆田市平海湾海水养殖区表层沉积物重金属污染和海水有机物污染情况,分析重金属生态危害程度和有机污染程度,本研究小组在研究区采集了具有代表性、典型性的表层沉积物和海水样品,通过采用瑞典科学家Hakanson提出的生态危害指数法及海水有机污染指数法等方法,研究确定研究区内表层沉积物中Cd,Hg两种元素生态危害程度达到中等,海水有机污染程度等级为2级,处于开始受到污染状态。进一步分析了研究区海水综合水质及富营养化等生态环境问题,以期对加强海水养殖生态环境监管、推动海洋生态问题研究以及推进海水养殖业绿色发展等方面提供参考。

福建平海湾外湾表层沉积物粒度特征及冲淤变化

通过对平海湾外湾106个表层沉积物样品的粒度分析,阐述了平海湾外湾表层沉积物的物质组成和粒度参数分布特征.利用沉积物粒径趋势模型初步探讨了平海湾外湾的沉积物输运趋势,结合新老海图对比,分析了该海域的冲淤变化特征,并结合平海湾发展规划选取代表站位来分析计算潮流和波浪对海底沉积物的冲刷.结果表明,研究海域表层沉积物可分为5种类型,主要为粘土质粉砂,随着水深的增加,沉积物呈逐渐变细的趋势.沉积物的平均粒径(Mz)、分选系数(σi)、偏态(S_(ki))及峰态(K_g)的分布与研究区海域沉积环境和水动力条件等相对应.粒径趋势分析显示研究区表层沉积物的输运趋势主要为NW向和SE向.对比不同年代海图及观测资料表明,研究海域呈弱淤积状态;经过分析计算,研究区海底沉积物不是受到潮流而是波浪的冲刷.

福建平海湾沉积动力特征与海床稳定性分析

结合平海湾海域规划,通过对平海湾岸滩地质地貌考察、水深测量、底质采样与分析、海域水文泥沙测验与资料分析、海域泥沙运动分析计算和新老图件对比分析等综合手段研究,结果表明:平海湾区周边无大河、溪注入,陆域和海域来沙量小,海域和沿岸泥沙活动不大.湾内水动力条件相对较弱,海底沉积物以粘土质粉砂为主,湾东北侧沿岸浅水区至湾口区的平海村近岸以较粗的砂和砂质粉砂沉积物为主.湾内岸滩总体属于基本稳定状态,但其内湾潮滩、内湾的北部和东部岸滩处于弱淤积状态,波浪输沙往湾顶岱前段净输沙量为5.37×104m3/a,而西侧和西南岸滩处于弱的冲刷状态,山柄村向南往湾外净输沙量为1.97×104m3/a,但总体而言,海岸蚀退的速度相当缓慢.平海湾自1970～2007年的37a来,在平海湾海域水深5m以浅的内湾海域呈弱的淤积趋势,淤积速率仅为0.018 m/a.

平海湾海上风电场船舶交通流分析

文章基于平海湾真实的交通流数据,采用核密度法统计平海湾风电场址所在海域网格单元交通流量值,进而绘制出风电场周边海域船舶核密度图,为风电场的选址及对通航环境、水上交通秩序的影响分析提供依据,对国内海上风电场选址优化调整研究决策具有重要的参考价值。

惠州平海湾沿海沙滩沙生植被资源现状研究

2019年7月,采用路线法和样方法对惠州平海湾沿海沙滩沙生植被资源进行了实地调查。结果表明:平海湾沿海沙滩共有沙生植物131种,隶属于43科113属;生活型以草本植物为主,占种数的66.41%。科和属的地理成分具有明显的热带性质。群落类型有厚藤群落、单叶蔓荆群落、厚藤+单叶蔓荆群落、木麻黄群落、海边月见草群落、鬼针草群落、粗根茎莎草群落、香附子群落、苦郎树群落、狗牙根群落、铺地黍群落、匐枝栓果菊群落、盐地鼠尾粟群落、草海桐群落等。为保护好平海湾沿海沙滩沙生植被资源,建议将沙生植被纳入海岸带植被保护对象,加强环境管理,积极开展生态旅游等。

莆田市平海湾地下水质量现状及污染因子贡献度分析

国内外地下水污染问题已经引起越来越多人的关注,加强地下水现状评价与污染分析工作,对保护地下水生态环境,保障饮水安全实现人与自然和谐相处及可持续发展战略,具有重要的现实意义和深远的影响.莆田市平海湾地区拥有莆田最大的盐场—莆田盐场,工业、农业和养殖业较为发达,受以上因素及海水影响,该区地下水质量逐年下降,总结了平海湾地区地下水质量现状,并分析其污染原因,对当地相关部门在地下水生态环境保护及地下水资源污染修复方面有一定的指导作用.

基于单因子和模糊数学综合评价法的莆田市平海湾地下水环境评价

为了更准确了解莆田市平海湾地区地下水水质概况,分别采用单因子评价法和模糊数学综合评价法对平海湾地区20个地下水水质进行评价分析,并将二者评价结果进行分析对比。结果表明模糊综合评价法由于考虑了水环境的复杂性和分级界限的模糊性,根据各水质指标的实际状况赋予其相应的权重,得出的结果相对于单因子评价法得出的结果乐观,而单因子评价法结果过于悲观。建议采用多方法联合评价,更能体现平海湾地区地下水水质状况。

预制舱式升压站在平海湾海上风电场F区工程的应用

通过对平海湾海上风电场F区220kV升压站介绍,为升压站预制舱布置方式在其它风电场工程升压站建设中应用提供借鉴。

福建省莆田市海水养殖环境质量评价

为给海水养殖规划提供环境质量参考,采用渔业环境标准评价福建省莆田市四大养殖区环境质量(兴化湾XH、南日岛NR、湄州湾MZ、平海湾PH)。结果显示,兴化湾水和沉积物环境质量均最差,水中DIN、DIP、油类超标,按站位超标率大小顺序依次为DIP、DIN、油类,其它三海区水质均能满足渔业养殖需要,所有海区的沉积物质量均满足需求。

钢丝网骨架塑料(聚乙烯)复合管在跨海供水工程中的应用

平海湾跨海供水工程跨海段采用钢丝网骨架塑料(聚乙烯)复合管新型管材、铺管船铺管、后挖沟机挖沟等先进施工工艺,通过热熔对接和电熔套筒连接,恒张力、滑轮轨道及托管架放管,解决了钢丝网骨架塑料复合管在海上连接、安装过程中存在的接头和应力控制的难题,保证了工程质量和工期,节约了投资,取得了显著的社会经济效益。该文对此进行了总结,供类似工程参考。

Progress in Studies on the Equilibrium Shape of Headland-bay Shoreline

Research on the laws controlling the shoreline equilibrium shape has been one important topic of studying the evolvement and stabilization of sandy coasts. After a brief review of the progress on the equilibrium shape laws research, five models are introduced in detail. Advantages and disadvantages of these models are then discussed, which leads to the conclusion that the empirical formula integrating with analysis of mechanism should be the future direction of study on the headland-bay equilibrium shape laws. Finally, the importance of the study on the equilibrium shape of headland-bay in China is also discussed.

海上风电单桩基础嵌岩施工参数确定方法研究

队超大直径单桩嵌岩施工的工程实践中揭露了滚刀破岩的机理:钻机在钻压和扭矩的作用下,通过滚刀滚压岩石,使滚刀在岩石面上做旋转运动,并造成岩石非连续性破坏,滚刀滚压破岩过程中岩石主要受冲击压碎、剪切碾碎和拉裂破碎作用。根据能量守恒定律.论证了破岩钻进四大工艺要素,即钻机的破岩扭矩、钻压、转速和排渣量的计算方法;基于NTH模型,建立超大直径滚刀破岩受力模型,提出超大直径嵌岩钻机破岩钻.进参数计算方法;依托平海湾风电工程进行了实例计算,证明了文中提出的计算方法可用于超大直径破岩钻机的选型计算。

Sea Surface Effects on Sound Scattering in the Persian Gulf Region Based on Empirical Relations

In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogden and Erskine＇s experiments, sound scattering from the sea surface has three different regimes in which two mechanisms of surface roughness and subsurface bubble clouds are involved. Ogden-Erskine＇s scattering relation which consists of perturbation theory and Chapman-Harris＇s scattering terms are verified by the experimental data of Critical Sea Tests 7. Subsequently, wind speed in the Persian Gulf is provided based on three data bases of Arzanah station, ERA40, and PERGOS. Accordingly, surface scattering strength in the Persian Gulf region is calculated at different grazing angles, frequencies and provided wind speeds. Based on the resulted values of scattering strength, scattered intensity from the sea surface is also studied. These studies indicate that both scattering strength and scattered intensity generally increase as grazing angle, frequency and wind speed increase.

Study on the Marine Sedimentary Environment Evolution of the Southern Laizhou Bay Under the Impact of Port Projects

The southern Laizhou Bay is mainly composed of silt-sandy coasts with diverse landforms, and its marine hydrodynamic environment is sensitive to human activities. Marine hydrodynamic and sedimentary environments of the study area have changed under the influence of large-scale port projects in recent years. In this paper, the evolution of hydrodynamic environment, deposition rate, and geochemical characteristics were studied based on sediment grain size, element analysis and ^(210)Pb dating of two cores, in order to analyze the influence of Weifang Port on marine environmental evolution, and provide theoretical and practical basis for protecting marine environment in developing marine resources reasonably. Results showed that sediments of the two cores were relatively coarser and mainly composed of silty sand. Sediments above 230 cm in core WF1 and 218 cm in core WF2 were deposited since 1855 when the Yellow River appeared to deposit its sediments within the modern active delta, and the average deposition rate was between 0.3 and 0.5 cm a^(-1). Implement of Weifang Port projects in 1997 and 2007 created great influence on the sedimentary environment evolution in the surrounding waters, and the deposition rate was significantly increased. The average annual deposition rates were 5.1 cm and 3.5 cm in WF1 and WF2 respectively between 1997 and 2007. Content of heavy metals in sediments showed no obvious change in the vertical, indicating that the heavy metals were less affected by human activity and there was no significant accumulation of such metals in the study area.

Late Quaternary sedimentary environmental evolution offshore of the Hangzhou Bay,East China——implications for sea level change and formation of Changjiang alongshore current

This study focuses on sedimentary environmental changes offshore of Hangzhou Bay, East China, since the Late Quaternary. AMS ^14C ages from core CJK10, lithologies, distribution of foraminifera, heavy minerals, and S and C1 elements show a fluvial terrace environment during -23.2-11.0 cal ka BP; a littoral to tidal-flat environment during 11.0-10.2 cal ka BP; and a shallow marine environment with a relatively low sedimentation rate （0.1-0.22 cm/a） since 4.3 cal ka BP. High depositional rates （-1.6 cm/a） from 10.9 to 10.2 cal ka BP resulted from sufficient accommodation space created by rapid sea level rise from -44 m to -33 m, from high sediment delivery by local rivers, and effective trapping of sediments by tidal-flat vegetation. The rate of sea level rise was variable; relatively high from 10.9 to 10.6 cal ka BP （2.1 cm/a）, and lower since 10.6 cal ka BP （1.2 cm/a）. The Changjiang alongshore current crossed the Hangzhou Bay to form the mud wedge on the inner shelf of the East China Sea later than 9.4 cal ka BP. The CJK10 site was a tide-dominated shelf environment and experienced erosion from approximately 9.4-9.2 cal ka BP to 4.3 cal ka BP. The depositional hiatus was caused by the Changjiang alongshore current, which was relatively weak during 9.4-7.5 cal ka BP and increased in strength during -7.5-4 cal ka BP. From -4.3 cal ka BP, a large amount of sediment from the Changjiang River was partly deposited on the continental shelf of Hangzhou Bay with some transported southward. Therefore, this study clarifies the history of Changjiang-derived sediment dispersal and deposition, although a detailed record of the changes in the Chang3iang alongshore current since 4.3 cal ka BP is difficult to obtain because of the scarcity of evidence.

Distribution of nutrients and eutrophication assessment in the Bohai Sea of China

Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average concentration of DIN increased and the PO4-P concentration sharply decreased compared to the previous data of corresponding period. The high concentrations of DIN and PO4-P occurred in coastal waters, especially in the bays and some river estuaries, while the high concentrations of SiO3-Si in the surface and middle depth occurred in the central area of the Bohai Sea. The average ratio of DIN/PO4-P was much higher than the Redfield Ratio （16：1）. Apparently, PO4-P was one of the limiting nutrient for phytoplankton growing in the sea. The average concentrations of DON and DOP were higher than their inorganic forms. The results of eutrophication assessment show that 22.1% of all stations were classified as violating the concentration levels of the National Seawater Quality Standard （GB 3097-1997） for DIN and only 3.9% for PO4-R The average eutrophication index in the overall area was 0.21±0.22 and the high values occurred in Bohai Bay, Liaodong Bay and near the Yellow River estuary. This means that the state of eutrophication was generally mesotrophic in the Bohai Sea, but relatively worse in the bays, especially some river estuaries.

The application of stereo-video technology for the assessment on population change of black rockfish Sebastes schlegeli in a vessel reef area in Haizhou Bay,China

The assessment of population structure and abundance of fish assemblages associated with artificial reefs(ARs) is an important aspect of AR management.In the present study,we used a DiveOperated Stereo Video(stereo-DOV) technique to assess the population structure and abundance of Sebastes schlegeli associated with two metallic,and three wooden,vessel reefs in Haizhou Bay during 2012 and2013.The study used video systems to obtain length measurements and estimates of abundance.The size composition of S.schlegeli differed among reefs and individuals around vessel reefs were all adults,with total lengths(TL) of >20 cm.Juvenile fish were encountered by divers in a rocky area near the island away from the vessel reefs.The largest individual S.schlegeli(with the highest TL) among five reefs were found around a metallic vessel reef in both 2012 and 2013.TL of S.schlegeli from all reefs increased by an average of 3.2 cm(P<0.05) from 2012 to 2013,with an estimated mean weight increase of 250.4 g(P<0.05).The video survey also indicated a decrease in the biomass of schools near two metallic vessels between the years.Stereo-video technology was found to be suitable for rockfish surveys around the reefs.

Mean trophic level of coastal fisheries landings in the Persian Gulf(Hormuzgan Province), 2002–2011

Fishing activities can alter the structure of marine food webs by the selective removal of some species. The changes in the marine food webs of the Hormuzgan waters of the Persian Gulf, Iran were assessed, based on estimates of the mean trophic index （MTI） and Fishing in Balance index （FIB）, and on landing profile of the exploited marine community （49 species） during the period, 2002-2011. The total landings （Yt） （R=0.88, P〈0.001） increased gradually while the Y~ of carnivores has slightly declined, and the Yt of herbivores, detritivores and omnivores has increased. Consequently, the MTI significantly decreased （R=-0.69, P〈0.05） at a rate of 0.1 l during this decade. The MTI showed a decreasing trend, which indicates exploitation of marine resources. The FiB index also showed a downward trend and negative values from 2002 to 2009, which may be associated with unbalanced structure in the fisheries, but an upward trend from 2009 to 20ll. The time variation of the landing profile showed two periods with significant differences in their species composition （R=0.88; P=0.005）, and based on analysis of similarity, species have been identified as discriminator species, namely Thunnus albacores and Benthosema pterotum. Results indicate that changes in MTI reflected changes in the Hormuzgan landing structure. The examination of the MTI, FBI, and landing profile （LP） temporal pattern suggests that the status of fishery resources in Hormuzgan inshore waters is overexploited, and provides evidence of the probability that a fishing down process is occurring in this area, and that this trend may continue in the long-tenn. Therefore, environmental fisheries management and conservation programs should be prioritized for these valuable resources.