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1.
大亚湾水域营养盐的分布变化 总被引：13，自引：0，他引：13
本文通过对大亚湾水域溶解氧，氮、磷、化学耗氧量、盐度、ＰＨ等环境因子的调查，对该水域溶解氧的含量分布和季节变化进行了分析，同时，对湾内ＮＯ３－Ｎ、ＮＯ２－Ｎ、ＮＨ４－Ｎ及ＰＯ４－Ｐ的时空分布以及季节变化规律进行了讨论，并以氧的饱和度、ＰＨ、化学耗氧量、无机氮等单项指标和综合指标研究了该水域的富营养状况。 相似文献
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湄洲湾海域夏秋季水质状况 总被引：4，自引：0，他引：4
１９９２年夏季和秋季对湄洲湾海域水质进行两期的调查研究，除观测主要水文气项目外，重点调查水化学要求，监测项目：盐度、ＰＨ、溶解氧、化学耗氧量、生化需氧量、无机氮、活性磷、石油类等。本文将调查数据整理分析。 相似文献
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莺歌海三莺村岸段人工沙滩工程岸线数值模拟以及模型的验证方 总被引：1，自引：0，他引：1
以乐东莺歌海三莺村岸段人工沙滩工程为例,其完工1年后的岸线监测结果,表明需要进一步对人工沙滩后的海滩岸线演变进行研究分析。通过GENESIS岸线演变模型模拟人工沙滩后的岸线变化,并尝试采用3种方法对模型进行验证。经过验证后,对人工沙滩工程后1年、3年、5年岸线变化进行了模拟分析。研究结果表明:GENESIS岸线演变模型对于包围型(拦沙堤和离岸堤结合方式)人工沙滩工程是适用的。工程完工1年后,补沙岸线形成了侵淤变化的凹凸弯曲岸线,侵淤幅度不大,5年后侵淤幅度变缓,开始逐渐趋于平衡。据此,也为人工沙滩后期的养护、补沙防护工作起到重要的参考作用。 相似文献
4.
为加强惠州市海洋生态环境保护工作,并为其提供科学依据,文章利用2016年春季和夏季惠州市海洋环境综合调查数据,选取溶解氧、化学需氧量、无机氮和活性磷酸盐4个环境因子,分析其近岸海域和海洋基本功能区的海水环境质量,并评价海水有机污染状况。研究结果表明:春季近岸海域海水环境质量优于夏季,无机氮和活性磷酸盐为主要超标因子;港口航运区海水环境质量良好,其他功能区均有环境因子超标现象;近岸海域受到有机污染,旅游休闲娱乐区在2个季节均受到有机污染;海水环境尚未对海洋生物产生影响。 相似文献
5.
This study (2002/2004) examines the effect of artificial reef (AR) structures off the southern coast of Portugal on biogeochemical process and nutrient cycling. Organic and inorganic carbon, nitrogen, phosphorus and chlorophyll a were determined monthly in sediment cores and settled particles for a two-year period. Ammonium, nitrates, phosphates, silicates, total organic nitrogen and phosphorus, chlorophyll a and phaeopigments were also determined monthly in water samples within AR and control sites. Results of the two-year study showed that: (i) there was a significant exponential fit between organic carbon and chlorophyll a (r2=0.91; p<0.01) in reef sediment suggesting an increase of benthic productivity; (ii) organic carbon and nitrogen content in settled particles within AR environment was about four times higher two years after reef deployment; (iii) nutrients and chlorophyll a in the water column were higher at AR than control site. Two years after AR deployment, dissolved organic and inorganic compounds in near bottom water were 30-60% higher, emphasizing benthic remineralization processes at AR's organically rich sediment. Marked chemical changes in the ecosystem were observed during the two-year study period, reinforcing the importance of these structures for sandy coastal areas rehabilitation through trophic chain pull-out. 相似文献
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M. Falco M.N. Santos T. Drago D. Serpa C. Monteiro 《Estuarine, Coastal and Shelf Science》2009,83(4):451-459
The present study investigates the differences between nutrient fluxes and particulate organic matter within an artificial reef system (AR) deployed in August 2002 off Faro (Algarve, Southern Portugal) and in a non-reef area (NRA), and how fluxes and suspended material may be affected by the hydrodynamic regime. Surveys to collect sediment cores, suspended/settled particles and overlying water samples were carried out by divers, from March (2006) to October (2007) in AR and NRA. Sediment cores and settled particles were collected to determine grain size, organic and inorganic carbon, nitrogen and phosphorus content. Overlying water and pore water samples were analysed for ammonium, nitrite, nitrate, phosphate, silicate, dissolved organic nitrogen, dissolved organic phosphorus and chlorophyll a. Results from the period studied showed that: (1) the benthic export of dissolved N, P and Si was 2–3 times higher at AR; (2) the particulate organic carbon (POC), nitrogen (PON) and phosphorus (POP) in suspended/settled particles were about 1.5 times higher at AR; (3) at both AR and NRA, the benthic export of dissolved N, P and Si, during a calm weather period, was 2–4 times higher than during or immediately after a storm event; and (4) at both sites, particulate organic compounds (POC, PON and POP) increased about 20 times during a storm event. These findings suggest that both the nutrients transport from sediment to water column and the quantity/quality of suspended/settled particles were highly dependent on the existence of reef structures and on the hydrodynamic regime. 相似文献
9.
于2003年8月28日对奥运帆船赛场海域海水水质要素进行了现场调查,并以无机态氮(DIN)、无机态磷(PO4-P)、化学耗氧量(COD)、溶解氧(DO)为化学指标参数,探讨了该海域的富营养化状况。结果表明,奥运会帆船赛场海域除石油烃外,大部分海域符合国家一类海水水质标准,石油烃平均含量超过国家二类水质标准。该海域调查海区PO4-P、DIN主要受陆源排放影响,特别是浮山湾至石老人沿岸海域含量较高。部分区域已经开始呈现轻微富营养化状态,富营养化状况主要受陆源排放等因素的影响。整体上奥运会帆船赛场海域水质良好,污染较轻。 相似文献
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拦沙堤作为海滩养护最常用的辅助工程之一,在全球范围内得到广泛应用。在总结我国海滩养护过程中拦沙堤应用现状的基础上,将拦沙堤的功能分为3类（防泥沙扩散、防沿岸输沙、防浪+防输沙）,并详细分析这3类拦沙堤在我国海滩养护的应用现状和发展规律。基于国内外工程实践,进一步探讨海滩养护中拦沙堤的多项应用创新：组合式拦沙堤设计、拦沙堤平面形态优化、拦沙堤堤群设计、拦沙堤+潜堤组合优化、拦沙堤+旁通输沙/循环养护。最后,展望未来海滩养护中拦沙堤的发展应用趋势（拦沙量的精准调控、丰富多样的形态设计、基于“自然工法”的生态化建设）,并给出了相关建议。 相似文献
12.
- Studies on the erosion processes and protective measures at the downcoast of the Friendship Port in Mauritania have been successfully conducted by means of 3-D movable-bed model using light model-sand. The headland control was accepted for the stability of the beach. This paper mainly deals with the shape, orientation, size and erosion depth of the artificial headland. Various forms of headland projects, such as the normal groin, arch groins bending to upcoast ancj to downcoast, offshore breakwater, and T-shaped dike, have been experimentally investigated. Through a comparison of effects of these works on the beach processes, optimized headlands have been obtained, that is, unsymmetrical T-shaped dike or arch groin bending to the downcoast, which has been practically and successfully applied for the stability of beaches. 相似文献
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文章根据岙山监测浮标周边海域2015年9-12月水质调查资料,采用水质有机污染指数(A)、富营养化指数(E)和营养状态质量指数(NQI)等进行评价。结果表明:岙山监测浮标周边海域水质化学需氧量(COD)、溶解氧(DO)、油类(oils)符合二类海水水质标准,无机磷(DIP)和无机氮(DIN)含量均超过二类海水水质标准,DIP最高为0.048mg/L,DIN最高为0.753mg/L,总磷(TP)各月平均含量范围0.098~0.185mg/L,总氮(TN)各月平均含量范围0.650~0.818mg/L,叶绿素a(Chl a)含量基本稳定,DIN是主要的超标污染因子;富营养化评价结果显示,岙山监测浮标周边海域水质富营养程度严重,E值最高达9.10,NQI值最高为4.58;有机污染评价结果表明,岙山监测浮标周边海域水质总体处于轻度污染状态,A值最小为10月的1.90,最大为12月的2.73;使用A值、E值和NQI值方法同时对岙山监测浮标周边海域进行评价,其结果变化的一致性较好。 相似文献
14.
根据１９８８年７月调查资料讨论了台湾海峡中北部海域夏季上升流区各种形态磷的分布特征。结果表明，上升流中心区（即海坛岛东侧一带水域）具有低温、高盐、低溶解氧；ＤＩｐ，ＴＤＰ，ＰＰ，ＴＰ较高；ＤＯＰ较低（０．２７）；及ＤＩＰ／ＤＯＰ比值（约为１）较高的特性。ＤＯＰ是该海域磷的主要形态（占ＴＰ的４９．２％），其含量分布及其形态转化与生物活动直接相关，是该海域生物生产力高的体现。 相似文献
15.
薛春汀 《海洋通报(英文版)》2004,6(2):45-50
Excavating sands and gravel on land in combination with constructing reservoirs for storing fresh water is an ideal approach in atolls. Appropriate mining of gravel from the prograding gravel beach is acceptable. Digging reef rock close to the edge of the wide ocean reef flat without surface loose sediments on it or sand beach can be accepted. Excavating sand from some depths in lagoon is a scientific approach particularly important for urbanized atolls. However, selecting appropriate sites for mining sand other than at some depths in lagoon is suitable to rural islands without dense populations. These sites include up drift side of long groin on the reef flat,partly filled access channel-port, outlet of artificial channel and lagoon margin on the prograding coast. 相似文献
16.
我国硬式护岸、渔港工程和人工岛等3类典型海岸工程对相邻海滩有显著影响.本研究以泉州青山湾护岸、泉州崇武中心渔港、海口南海明珠人工岛等建设前后海滩变化为例,开展对海滩岸线形态及部分典型剖面形态的对比分析.结果表明,临海硬式护岸岸前海滩发生明显下蚀,护岸下游海滩岸线侵蚀后退,发育侵蚀热点,剖面伴有下蚀;渔港工程拦沙堤附近岸线局部淤涨,下游海滩岸线大范围侵蚀后退,出现侵蚀热点,侵蚀热点处剖面明显下蚀;人工岛后波影区内海滩淤积,形成沙岬或连岛沙坝突出体,突出体两侧岸线均发生不同程度侵蚀后退.通过分析典型工程案例,探讨了3类海岸工程对相邻海滩的影响方式、影响尺度和原因,对比分析不同类型海岸工程对相邻海滩的负面影响,可为海岸工程建设管理和海滩保护提供参考. 相似文献
17.
Management of a shallow temperate estuary to control eutrophication: The effect of hydrodynamics on the system’s nutrient loading 总被引：1，自引：0，他引：1
A.I. Lilleb J.M. Neto I. Martins T. Verdelhos S. Leston P.G. Cardoso S.M. Ferreira J.C. Marques M.A. Pardal 《Estuarine, Coastal and Shelf Science》2005,65(4):697-707
The Mondego estuary, a shallow warm-temperate intertidal system located on the west coast of Portugal, has for some decades been under severe ecological stress, mainly caused by eutrophication. Water circulation in this system was, until 1998, mainly dependent on tides and on the freshwater input of a small tributary artificially controlled by a sluice. After 1998, the sluice opening was effectively minimised to reduce the nutrient loading, and the system hydrodynamics improved due to engineering work in the upstream areas. The objective of the present study was to evaluate the effect of the mitigation measures implemented in 1998. Changes to the hydrodynamics of the system were assessed using precipitation and salinity data in relation to the concentrations of dissolved inorganic nutrients, as well as the linkage between dissolved N:P ratios and the biological parameters (phytoplankton chlorophyll a concentrations, green macroalgal biomass and seagrass biomass). Two distinctive periods were compared, over a ten year period: from January 1993 to January 1997 and from January 1999 until January 2003. The effective reduction in the dissolved N:P atomic ratio from 37.7 to 13.2 after 1998 is a result of lowered ammonia, but not the oxidised forms of nitrogen (nitrate plus nitrite), or increased concentrations of dissolved inorganic phosphorus. Results suggest that the phytoplankton is not nutrient limited, yet maximum and mean biomass of green macroalgae was reduced by one order of magnitude after the mitigation measures. This suggests that besides lowering the water residence time of the system, macroalgal growth became nitrogen limited. In parallel to these changes the seagrass-covered area and biomass of Zostera noltii showed signs of recovery. 相似文献
18.
粤东靖海湾海岸地貌动力演变及其工程影响 总被引：1，自引：0，他引：1
受人为工程的影响,相对稳定的岬湾海岸地貌常经历显著的动态调整。本文以粤东靖海湾典型岬湾海岸为例,运用Mc Laren模型、波浪动力场数值模拟、等深线对比、冲淤计算等多种方法,从海岸地貌动力学角度,对人为岬角工程前后岬湾海岸地貌动力过程和冲淤演变进行综合分析。结果表明:1)海岸地貌动力系统内常存在负反馈机制以维持系统的稳定。岬角工程后上岬角防波堤沿SSW延伸,ESE和E向浪经过防波堤时发生绕射,波能削减,湾顶动力减弱,海滩沉积物从下岬角向湾顶反向运移;2)海滩的蚀积状态在工程前后发生了转换,工程前遮蔽段侵蚀、开敞段堆积;工程后遮蔽段堆积、开敞段侵蚀;3)海湾水下地形对岬角工程的响应敏感,工程后海湾水下地形冲淤剧烈。 相似文献
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LIU Sumei ZHAO Yingfei REN Jingling ZHANG Jing SUN San JIN Jie ZHANG Guiling 《海洋学报(英文版)》2010,29(1):42-51
Phosphorus (P) is an essential nutrient utilized by all organisms for energy transport and growth.
Both the conventional molybdenum-blue method and the magnesium-induced coprecipitation
(MAGIC) procedures were applied for the measurement of dissolved inorganic phosphorus (DIP)
and total dissolved phosphorus (TDP) in more than 840 water samples collected between 2003 and
2005, including seawater (the Huanghai Sea, the East China Sea, and the northern South China
Sea), water from rivers and estuaries (the Changjiang, the Huanghe, and the major rivers emptying
into the Jiaozhou Bay), groundwater (in the drainage basin surrounding the Jiaozhou Bay), rain-
water, and aquaculture water samples. The MAGIC method allows the investigation of phosphorus
distributions and cycling for systems in which DIP is below the detection limits of conventional
methods. Comparison between the two methods demonstrated that the concentrations obtained
with both methods were signiˉcantly correlated. The di?erences of DIP and TDP concentrations
measured with the two methods were higher when the concentrations of DIP and TDP were lower,
implying the lower reproducibility at low concentrations. The concentration di?erences increase
with the increase in the proportion of DOP in TDP, which indicates that the discrepancy of DIP
concentrations measured with the two methods increases when the DOP concentration is high. The
discrepancies indicated that the composition of P compounds di?ers depending on sample sources
and water type; it would be useful to infer the presence of di?erent phosphorus compound pools
from di?erences between the two methods. This study indicates the potential presence of a pool
of alkaline-labile compounds for samples from rainwater and rivers and estuaries surrounding the
Jiaozhou Bay; the potential presence of acid-labile compounds that were adsorbed by Mg(OH)2 for
samples from the Changjiang Estuary, Huanghai Sea, East China Sea, and groundwater; the po-
tential presence of a substantial pool of acid-labile compounds that were not adsorbed by Mg(OH)2
for samples from the Huanghe Estuary, aquaculture water, the East China Sea algal bloom water,
and the northern South China Sea. 相似文献
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闽南-台湾浅滩渔场上升流区研究(1987年12月至1988年11月)及台湾海峡上升流区研究(1987年7月至1988年7月)结果表明,各种形态磷含量变化对上升流生态系具有重要作用.因此,提出以涌升水体中有机、颗粒形态磷和溶解无机态磷的相对比率来表示上升流水体的老化程度,即上升流水体老化指标(AIU)为(DOP+PP)与(DIP＋DOP＋PP)之比值.研究资料表明AIU这一表达式对于上述两上升流区是合适的,海域AIU的季节性变化与其近岸上升流的消长变化规律相一致.AIU较小的区域,其水体为新涌升水,与上升流中心位置相吻合. 相似文献