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江苏近岸海域表层海水中营养盐组成、分布及季节变化特征 总被引：1，自引：0，他引：1
根据2014~2015年江苏近岸海域4个航次现场调查资料,分析探讨了该海区表层海水的溶解无机氮(DIN)、活性磷酸盐和硅酸盐含量及分布特征,并对江苏近岸海域表层水质进行富营养化评价。海区全年表层DIN平均浓度均符合国家4类海水水质标准,表层活性磷酸盐平均浓度均符合国家二类海水水质标准。DIN表现为冬季夏季秋季春季。NO_3-N在4个季节均为DIN的主要存在形态,NO_2-N的比例随水温的升高而呈上升趋势。灌河口和江苏海域南端启东嘴处为营养盐高值区,而海州湾是营养盐低值区。江苏近岸海域在夏季基本处于磷限制潜在性富营养。而秋季北部海域基本处于磷限制潜在性富营养,南部海域处于中度营养及富营养状态;冬季海州湾基本处于磷限制潜在性富营养,其余海域处于中度营养及富营养状态,春季海区整体呈现中度营养及富营养状态。 相似文献
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辽东湾北部海域营养状况与趋势评价 总被引：3，自引：0，他引：3
根据 1999-2006 年 6-8 月的调查数据,分析辽东湾北部海域的营养水平及变化趋势,以了解辽东湾北部海域营养水平的分布特点及污染状况.由 E 值和 CN/CP 值的总体评价结果来看,辽河口、双台子河口和大凌河口海域的富营养化程度较高,属于磷中等限制潜在性富营养区,而锦州湾海域污染相对较轻,属于中度营养区;在时空分布上,辽东湾北部海域 1999 年与 2006 年污染较为严重,中间年份污染相对较轻.针对辽东湾的具体环境用 CN/CP 值的评价模式更能揭示出营养盐限制对富营养化的影响. 相似文献
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文章利用2018年9—11月厦门岛西北海域的现场调查资料，在对海域水质污染状况和富营养化水平进行评价的基础上，分析并讨论浮游植物生物量粒级结构及其环境影响因素。研究结果表明:同安湾在11月处于富营养水平，属于中度或严重污染海域；九龙江口和西海域在9-11月均处于磷中等限制潜在性富营养或磷限制潜在性富营养水平，属于严重污染海域。同安湾和西海域浮游植物分粒级的生物量占比与九龙江口存在明显差异，前者由大到小依次为微型、小型、微微型，后者由大到小依次为小型、微型、微微型。小型浮游植物生物量与硝酸盐和亚硝酸盐、溶解无机氮、溶解无机磷以及活性硅酸盐呈显著正相关，与盐度呈显著负相关；微型浮游植物生物量与真光层深度、铵盐和溶解无机磷呈显著正相关；微微型浮游植物生物量与真光层深度、铵盐和溶解无机磷呈显著正相关，与pH值呈显著负相关。影响浮游植物群落粒级结构的最重要的海洋环境因子是盐度、真光层深度和溶解无机磷，尤其是溶解无机磷浓度，其值一旦升高，浮游植物极有可能从磷胁迫状态发展为赤潮。控制排污、实时监控、增强预警能力和改善生态环境是控制和预防营养盐污染以及赤潮暴发的有效手段。 相似文献
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胶州湾海水营养盐的分布及潜在性富营养化研究 总被引：2，自引：0，他引：2
根据2009年5、8、10月胶州湾海区3个航次海水营养盐的调查资料,分析了该海区海水营养盐的分布特征和时空变化,利用潜在富营养化评价模式评价水质营养状况。结果表明,溶解无机氮、活性磷酸盐以及活性硅酸盐的年均含量分别为0.335、0.028和0.725 mg/L,NO3-N是DIN的主要组成部分,占溶解无机氮含量的71.6%;8月营养盐含量高于5月和10月,营养盐的空间分布从东部河口区和北部养殖区两个高含量区向湾中心和湾口呈逐步递减之势;DIN∶P,Si∶DIN和Si∶P的比值年平均分别为53.9,2.03和57.7,活性磷酸盐为限制因素,胶州湾海域处于磷中等限制-磷限制潜在性富营养化,楼山河口和李村河口为中度营养-富营养,一旦有外界磷大量输入可能发生赤潮。 相似文献
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珠江口海域无机氮和活性磷酸盐含量的时空变化特征 总被引：17，自引：1，他引：17
主要利用1998年在珠江口海域连续同步观测资料，研究该海域无机氮、活性磷酸盐含量和富营养化状况。结果表明，无机氮主要来自四个口门的径流，但深圳湾附近的陆源亦有一定贡献；无机氮的形态主要以硝酸氮为主，而在深圳湾附近海域则以氨氮为主；无机氮含量普遍超过0．30mg/dm^3的我国海水水质标准二类标准值，大部分海域已超过0．50mg/dm^3的四类水质标准值，径流对活性磷酸盐含量的贡献不显著，而深圳湾附近的陆源则有明显的贡献，从珠江口附近由沿岸流和涨潮流带来的活性磷酸盐亦有明显的影响；除深圳湾附近海域活性磷酸盐含量超过0．030mg/dm^3的二类海水水质标准值外，其他海域基本符合0.015mg/dm^3的一类海水水质标准值要求。该海域的N／P值普遍较高，而且北部海域的高于南部海域；最高值超过300，最小值也大小30；该水域的营养盐主要为磷限制。 相似文献
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莱州湾西南部海域及其毗邻河流水体营养盐的分布特征及长期变化趋势 总被引：2，自引：0，他引：2
根据2012年9月对莱州湾西南部海域及其毗邻10条河流的调查结果,以及近30年来关于莱州湾海域表层水营养盐的调查资料,报道了各条河流和近海海域的营养盐状况及该海域营养盐的长期变化趋势,结果表明:(1)10条主要调查河流的总溶解态氮(TDN)平均含量在1.82~10.66mg/L之间,其中有8条河流超过河流总氮劣五类水质标准,6条河流硝态氮(NO3-N)含量高于氨氮(NH4-N)。(2)所调查的5个近海断面中小清河口近海断面、虞河口近海断面及溢洪河口近海断面的DIN平均含量超过海水无机氮第四类水质标准;除小清河口近海断面外其余近海断面活性磷(PO4-P)含量均属一类海水水质。(3)部分断面营养盐含量在河口混合区淡水端升高,可能与咸淡水混合动力作用相关;莱州湾西部区域营养盐含量高于南部区域,南部的堤河氮、磷含量极高;原油开采活动可能是影响附近水体中营养盐含量及形态的重要因素。(4)从20世纪80年代初至90年代中期,莱州湾表层水无机氮平均含量经历了由低到高的变化,到90年代后期已属劣四类海水水质;无机磷平均含量在该时段呈降低趋势,但到90年代后期也保持在较高水平,随后又波动下降。(5)所调查的莱州湾近海区域整体处于磷限制潜在富营养状态;氮磷摩尔比(N∶P)在所考察的大部分时段内高于Redfield阈值(16),净营养盐收支呈磷减少而氮增加的总体变化趋势,近年来磷限制程度有所减缓。 相似文献
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文章以2013年4月底和11月中旬对盐城大丰港周边海域开展的海域水质现状调查结果为依据,分析讨论了该海域富营养化指数和营养状态质量指数的分布现状。结果显示:春秋两季富营养化指数范围分别为3.34~13.70、1.66~15.96,平均值为7.70和6.35;春秋两季营养状态质量指数范围分别为3.35~9.80、2.93~6.03,平均值为4.69和4.09;富营养化指数与营养状态质量指数分布总体呈现由西向东递减,王港河河口附近有高值区,说明大丰港海域营养盐主要还是受陆源污染影响;两种评价方法显示大丰海域的富营养化程度的趋势基本一致,即大丰港海域富营养化程度较高,水质状况较差;利用N∶P摩尔比值进行潜在性富营养化评价中发现,大丰港海域水体中无机氮水平较高,活性磷酸盐的含量相对不足,大丰港周边海域属磷限制潜在性富营养水平。 相似文献
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The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ～200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ～380 km from the coast at a depth of ～250 m above the sea level. 相似文献
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We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances
using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium
partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and
in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority
accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative
abundances of organic and inorganic carbon as an index of the carbon cycle stability. 相似文献
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We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the
Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of
rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the
transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic
regime of the sea.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
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双壳贝类血淋巴中儿茶酚胺的检测方法初步研究 总被引：1，自引：0，他引：1
研究的目的是探索一种检测双壳贝类血淋巴中儿茶酚胺含量的方法。以栉孔扇贝(Chlamysfarreri)和长牡蛎(Crassostreagigas)为实验对象,研究了取样、抗氧化剂、氧化铝用量以及Tris缓冲液用量等对实验结果的影响。结果表明,高效液相色谱电化学检测器法(HPLC-ECD)可以灵敏高效地对双壳贝类血淋巴中儿茶酚胺进行定性、定量检测。实验表明,取样时间最长不超过1.5min;还原性谷胱甘肽作抗氧化剂效果较好;前处理各试剂与血样量的最适配比为血样量1.5mL,Tris缓冲液(1.5mol/L,pH8.6)1mL和氧化铝25mg;水洗后离心并尽可能吸干氧化铝中的水分。去甲肾上腺素、肾上腺素和多巴胺的回收率分别为53%~69%、47%~73%和48%~56%。 相似文献
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为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明：黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。 相似文献
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V. A. Ivanov S. P. Lyubartseva N. Mikhailova N. B. Shapiro 《Physical Oceanography》2001,11(6):509-524
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an
ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics
is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of
a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic
elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as
a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water
area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the
shelf zone and open sea.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
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The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared. 相似文献
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Relationship between the path of the Kuroshio in the south of Japan and the path of the Kuroshio Extension in the east 总被引：2，自引：0，他引：2
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry
dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly
goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with
the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then
passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state. 相似文献
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Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area. 相似文献
20.
I. E. Timchenko A. A. Primalenny V. D. Yarin E. F. Vasechkina E. M. Igumnova 《Physical Oceanography》2001,11(4):367-378
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of
the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption
(fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by
the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with
application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem,
which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge,
water exchange with the Black Sea, etc.).
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献