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1.
以2005年11月(秋季)和2006年5月(春季)灌河口海域中无机氮和活性磷酸盐的调查资料为依据,研究分析灌河口海域无机氮、活性磷酸盐的季节和平面分布特征。结果表明,灌河口海域无机氮和活性磷酸盐浓度较高,春季低于秋季;在平面分布上呈由河口向外海侧递减明显趋势;灌河口海域水体富营养化程度极高,极易引发赤潮的风险。  相似文献   

2.
袁国明  何桂芳 《台湾海峡》2012,31(4):472-478
2004~2008年期间,在大亚湾进行了春、夏季两航次水质的溶解氧(DO)、化学需氧量(COD)、活性磷酸盐(PO4-P)、无机氮(DIN)、石油类(oil)含量的监测,结果表明除溶解氧含量只是季节间变化外,其余均呈不断上升趋势,其中活性磷酸盐和无机氮含量升幅较明显,有超一类水质现象出现,且夏季水质普遍劣于春季.利用海湾内外水交换参数和这些年间污染物监测资料,估算以功能水质标准为控制目标的水环境容量,结果表明,大亚湾水质化学需氧量、无机氮仍有较大的环境容量,两者的环境容量分别为22 239 t/a和1 361 t/a;但活性磷酸盐和石油类环境容量偏小,两者的环境容量分别仅有19 t/a和23 t/a.  相似文献   

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海洋环境容量是沿海城市区域发展的重要约束条件之一,根据规划环境影响评价的特点,在计算近岸海域汇流区域内污染物排放总量的基础上,预测规划年污染物排海总量,从而制定陆源污染物排海总量控制措施和目标,优化调整规划方案,海洋环境容量的大小与海域特征和海水水质目标有关。文章以大连湾为例,在潮流场数值模拟的基础上,计算了大连湾受纳水体水质对排放源的响应关系,结合混合区的确定,计算了主要污染物COD、无机氮和活性磷酸盐的最大允许排放量,为各个排污口排放的不同污染物制定相应的排放与削减量提供依据。  相似文献   

4.
基于无结构网格的MIKE 3D模型,建立了长兴岛海域三维潮流水质数学模型.按照海洋功能区划的水质要求,综合分析离岸排放的特点,计算马家咀排污口的混合区面积及污染物浓度响应系数,进而对马家咀排污口近期和远期环境容量进行计算.结果表明,根据2012年海水水质现状,马家咀排污口近、远期混合区面积最大为0.046 5 km~2,各主要污染因子化学需氧量(COD)、无机氮(DIN)、活性磷酸盐(PO_4~(3-)-P)和石油类的剩余环境容量分别为812.0、143.7、25.6、59.7 t/a.  相似文献   

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随着国家对长江流域实施环境综合整治、浙江省委省政府开展“五水共治”等环境整治工程,陆源入海污染物总量总体呈下降趋势,近几年舟山近岸海域环境质量呈好转态势。2007—2013年舟山近岸海域水质均不符合第一类海水水质标准,2014年符合第一类海水水质标准的海域有1 269 km2,仅占全市海域面积的6.1%,海水质量总体形势不容乐观,水体富营养化程度较高,海洋功能区水质达标率较低。通过对舟山海域84个二级类基本功能区水质达标率进行统计分析,2012—2014年海洋功能区水质达标率分别为35.7%、38.1%和44.0%,超标因子为无机氮和活性磷酸盐。  相似文献   

6.
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  
黄小平  黄良民 《台湾海峡》2002,21(4):416-421
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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珠江口海域春季富营养化现状与影响分析   总被引:1,自引:0,他引:1       下载免费PDF全文
随着珠江三角洲经济圈的迅速发展,珠江口海域环境污染日趋严重,于2014年春季对珠江口邻近海域进行环境现状调查,并通过因子分析法和聚类分析法就珠江口调查海域管辖城市和邻近区域的环境现状对珠江口海域环境污染的贡献率进行排序和分类.结果表明:珠江口调查海域营养盐污染较为严重,无机氮含量范围为0.213~1.963 mg/dm~3,平均值为0.888 mg/dm~3;活性磷酸盐含量范围为0.009~0.063 mg/dm~3,平均值为0.033 mg/dm~3.无机氮和活性磷酸盐在珠江口上游和中游均超过海水水质第四类标准,珠江口下游无机氮含量符合海水水质第四类标准,活性磷酸盐含量符合海水水质第二类标准.无机氮以硝氮为主,氨氮次之,亚硝氮含量最低.珠江口调查海域DIN/P变化范围为8.5~168.0,平均值为31.8;富营养化指数E变化范围为0.3~45.1,平均值为8.2,富营养化较为严重.来自广州、东莞、佛山、中山的四大口门排入的污染物对珠江口海域环境影响最大,其次是深圳西部海域沿岸和前海湾、深圳湾排入的污染物,最后是珠海、澳门和香港带入的污染物.从珠江口邻近海域环境现状对珠江口海域环境影响进行较为深入地分析和探讨,为珠江口海域环境的治理和修复提供一些意见和建议.  相似文献   

8.
《海洋预报》2021,38(3)
以2019年大辽河口海域水环境调查资料为基础,构建了二维流体动力学方程和水质控制模型,运用保守物质扩散方程,求得污染源排放量-输出响应浓度相关方程,用反演迭代法计算该海区污染源的环境容量。按照海洋功能区划水质标准,以不同类型功能区管理环境要求为控制目标,计算污染物COD、无机氮和磷酸盐的标准环境容量。按污染物承载力等级标准来评价,该海区环境承载力的结果为COD和磷酸盐可载,无机氮严重超载。最后,利用计算机语言编写的海域污染物承载力预警系统对海域环境承载力进行评价和预警。  相似文献   

9.
2011年夏秋季辽东湾营养盐分布及环境容量研究   总被引:1,自引:0,他引:1       下载免费PDF全文
利用2011年夏季和秋季辽东湾海域水质现场调查资料,讨论了整个辽东湾海域氮、磷营养盐的分布特征,进而通过计算富营养化指数(EI)和氮磷比(N/P)对辽东湾富营养化现状进行了评价,并估算了无机氮和活性磷酸盐的环境容量。结果显示,无机氮(DIN)和PO4-P浓度均呈现出河口大于远海、底层大于表层、秋季大于夏季的特征。夏秋季海水EI值均大于1,富营养化状况较为严重;海水N/P值大于16,营养盐结构严重不平衡,浮游植物生长处于显著的磷限制状况。整个辽东湾PO4-P环境容量仍有剩余,DIN环境容量夏季仅有极少余量,秋季已无余量,需对DIN的入海负荷进行大力削减。  相似文献   

10.
通过分析海河口及其邻近海域2005-2010年进行的多次环境现场调查资料,同时结合历史数据进行对比分析,结果表明:(1)河口水体中COD、BOD5、氨氮是突出污染因子,海河口水体污染程度整体呈现先降低再升高的趋势而大沽排污河河口区域水质状况相对更差整体仍然呈现进一步恶化态势;邻近海域水体中无机氮为最主要污染物,而其中硝酸盐是无机氮中最主要组成部分,不过亚硝酸盐所占比例正在逐年升高,说明区域水体氧化还原环境潜在变化正在发生;(2)丰水期陆源大量无机氮输入使得区域水体大部分时间超该区域功能区划要求的Ⅳ类海水水质标准;不过底质沉积物环境相对比较稳定,各监测项目全部符合一类海洋沉积物质量标准要求;(3)与1983年历史监测数据相比,海河口邻近海域活性磷酸盐、无机氮含量增速迅猛,丰水期时最高增幅活性磷酸盐和无机氮分别高达了2430%和5919%;整体看来同一时期水质和底质环境有缓和趋势,但潜在威胁仍然严重;最后,在认真分析对海河口及其邻近海域造成污染的各污染源基础上,进一步提出了有针对性的对策建议。  相似文献   

11.
鳚亚目 4 科 33 属 95 种,鰕虎鱼亚目 5 科 98 属 259 种,刺尾鱼亚目 5 科 11 属 65 种,鲈形目 19亚目 104 科 535 属 1799 种。  相似文献   

12.
Soil-sized particulates have been collected on board ship by a mesh technique from the lower troposphere of the North, Equatorial and South Atlantic Ocean, northern and southern Indian Ocean, South and East China Sea and various coastal localities.Spectrographic analysis reveals that, on average, the particulates have concentrations of Mn, Ni, Co, Ga, Cr, V, Ba, and Sr which are of the same order of magnitude as those in average crustal material. In contrast, the average concentrations of Pb, Sn, and Zn are one order of magnitude higher than those in average crustal material.Within this “world-wide” average there are significant geographical variations in the distributions of Pb, Sn, and Zn which may be related to anthropogenic sources.On the basis of trace-element distributions lower tropospheric soil-sized marine particulates have been divided into four genetic components; local, zonal, inter-zonal, and global. The proportions of these components vary geographically, and each component may have both a natural and an anthropogenic fraction.  相似文献   

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Tautog, Tautoga onitis, is an abundant species of fish in estuaries of the northeastern United States. Planktonic tautog larvae are abundant in summer in these estuaries, but there is little information on rates of growth of tautog larvae feeding on natural assemblages of food in the plankton. We examined abundance and growth of larval tautog and environmental factors during weekly sampling at three sites along a nearshore‐to‐offshore transect in Buzzards Bay, Massachusetts, USA during summer 1994. This is the first study of a robust sample size (336 larvae) to estimate growth rates of field‐caught planktonic tautog larvae feeding on natural diets, using the otolith daily‐growth‐increment method. The study was over the entire summer period when tautog larvae were in the plankton. The sampling sites contrasted in several environmental variables including temperature, dissolved oxygen (DO), and chlorophyll a concentration. There was a temporal progression in the abundance of tautog larvae over the summer, in relation to location and temperature. Tautog larvae were first present nearshore, with a pronounced peak in abundance occurring at the nearshore sites during the last 2 weeks in June. Larvae were absent at this time further offshore. From late June through August, larval abundance progressively decreased nearshore, but increased offshore although never approaching the abundance levels observed at the nearshore sites. The distribution and abundance of tautog larvae appeared to be related to a nearshore‐to‐offshore seasonal warming trend and a nearshore decrease in DO. Otoliths from 336 larvae ranging from 2.3 to 7.7 mm standard length had otolith increment counts ranging from 0 to 19 increments. Growth of larval tautog was estimated at 0.23 mm·day?1, and length of larvae prior to first increment formation was estimated at 2.8 mm indicating that first increment formation occurs 3–4 days after hatching at 2.2 mm. Despite spatial and temporal differences in environmental factors, there were no significant differences in growth rates at any of three given sites over time, or between sites. Because larval presence only occurred at a narrow range of temperature (17–23.5 °C) and DO (6.5–9.3 mg·l?1), in situ differences in growth did not appear to be because of differences in larval distribution and abundance patterns relative to these parameters.  相似文献   

18.
Results of trace-metal analyses of water samples obtained during a cruise with the Soviet R.V. “Akademik Kurchatov” in the Indian Ocean are presented. The determinations were performed on board with atomic absorption spectrophotometry after a two-stage dithiocarbamate—Freon extraction procedure. Trace-metal concentrations found are in the same range as those found recently for similar open-ocean areas by other workers. The values for lead and zinc are probably high due to contamination. Vertical profiles indicate biogenic processes as controlling factors for the increase of cadmium, copper and nickel concentrations with depth. Iron shows an irregular depth distribution as a result of large random variations in concentration.  相似文献   

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In June 1981, dissolved Zn, Cd, Cu, Ni, Co, Fe, and Mn were determined from two detailed profiles in anoxic Baltic waters (with extra data for Fe and Mn from August 1979). Dramatic changes across the O2H2S interface occur in the abundances of Cu, Co, Fe, and Mn (by factors of ?100). The concentrations of Zn, Cd, and Ni at the redox front decrease by factors between 3 to 5.Equilibrium calculations are presented for varying concentrations of hydrogen sulfide and compared with the field data. The study strongly supports the assumption that the solubility of Zn, Cd, Cu, and Ni is greatly enhanced and controlled by the formation of bisulfide and(or) polysulfide complexes. Differences between predicted and measured concentrations of these elements are mainly evident at lower ΣH2S concentrations.Cobalt proved to be very mobile in anoxic regions, and the results indicate that the concentrations are limited by CoS precipitation. The iron (Fe2+) and manganese (Mn2+) distribution in sulfide-containing waters is controlled by total flux from sediment-water interfaces rather than by equilibrium concentrations of their solid phases (FeS and MnCO3). The concentrations of these metals are therefore expected to increase with prolonged stagnation periods in the basin.  相似文献   

20.
Concentrations of dissolved nutrients (NO3, PO4, Si), germanium species, arsenic species, tin, barium, dimethylsulfide and related parameters were measured along the salinity gradient in Charlotte Harbor. Phosphate enrichment from the phosphate industry on the Peace River promotes a productive diatom bloom near the river mouth where NO3 and Si are completely consumed. Inorganic germanium is completely depleted in this bloom by uptake into biogenic opal. The GeSi ratio taken up by diatoms is about 0·7 × 10?6, the same as that provided by the river flux, confirming that siliceous organisms incorporate germanium as an accidental trace replacement for silica. Monomethylgermanium and dimethylgermanium concentrations are undetectable in the Peace River, and increase linearly with increasing salinity to the seawater end of the bay, suggesting that these organogermanium species behave conservatively in estuaries, and are neither produced nor consumed during estuarine biogenic opal formation or dissolution. Inorganic arsenic displays slight removal in the bloom. Monomethylarsenic is produced both in the bloom and in mid-estuary, while dimethylarsenic is conservative in the bloom but produced in mid-estuary. The total production of methylarsenicals within the bay approximately balances the removal of inorganic arsenic, suggesting that most biological arsenic uptake in the estuary is biomethylated and released to the water column. Dimethylsulfide increases with increasing salinity in the estuary and shows evidence of removal, probably both by degassing and by microbial consumption. An input of DMS is observed in the central estuary. The behavior of total dissolvable tin shows no biological activity in the bloom or in mid-estuary, but does display a low-salinity input signal that parallels dissolved organic material, perhaps suggesting an association between tin and DOM. Barium displays dramatic input behavior at mid-salinities, probably due to slow release from clays deposited in the harbor after catastrophic phosphate slime spills into the Peace River.  相似文献   

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