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《中国海洋大学学报(自然科学版)》2015,(11)
基于MIKE21软件,建立潮流、径流耦合作用下大沽河河口区氮磷营养盐输移转化数学模型。利用数学模型,对实测工况进行了模拟,并与相应的实测资料进行验证;在此基础上,对不同径流和排污条件下的氮磷营养盐分布进行预测分析。结果表明:大沽河口附近DO浓度较低,氨氮、硝酸盐和磷酸盐浓度较高。平水期流量条件下,上述物质进入胶州湾后有偏向河口右侧海岸的趋势。丰水期流量条件下,各水质参数的分布趋向均匀;上述物质进入胶州湾后基本上呈现以河口纵向主槽为对称轴,两侧对称分布的特征。不同排污条件下,河口附近DO从北向南基本呈现递增趋势,而氨氮、硝酸盐和磷酸盐则相反。一、二级污水排放条件下,河口附近DO符合一类海水水质标准;而无机氮和磷酸盐为超四类海水水质标准。 相似文献
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根据1998—2002年对古镇口港海域5期的监测结果，初步探讨了该海域环境因子的变化特征和营养水平。结果表明：该海域水质较好，除油类和CODMn外，1998年达到GB 3097—1997第一类海水水质标准，1999年水质超过第四类标准，2000，2001年水质达到第三类标准，2002年达到第二类标准。其中无机氮和活性磷酸盐含量近年略有上升，氮磷比平均为26．8。富营养化指数平均为37．2，并呈迅速下降态势，已从1999年的137降为2002年的0．733。但该水域受油类和CODMn污染较严重，CODMn的含量从1999年开始连续3年超过第四类海水水质标准，2002年明显好转，达到第一类海水水质标准；油类的含量连续5a达到第三类海水水质标准。综合来看，古镇口港海域水质目前状况较好。 相似文献
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由于厦门西海域独特的地理位置,周边城市规模扩大和经济发展,使得厦门西海域承受沉重的环境负载.本文根据厦门西海域功能特点,以及在对厦门西海域水质状况分析的基础上,分析了西海域对主要排海污染物的环境承载力.西海域无机氮和无机磷平均含量基本符合四类或超四类国家海水水质标准,西海域已无无机氮和无机磷承栽能力;西海域化学耗氧量、重金属(铜、铅、镉、汞和砷)和油类还存在相当的承载能力. 相似文献
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模拟添加氮对海水溶解无机碳体系的影响 总被引：1，自引：0，他引：1
碳和氮作为主要的生源要素对维持海洋生态系的正常运转起着至关重要的作用,碳与氮的变化是相互耦合的且呈双向作用,为探讨海水无机碳与氮的相互作用规律,研究了室内模拟添加硝酸盐对海水无机碳体系pH、溶解无机碳(DIC)、HCO3-、二氧化碳分压(Pco2)的影响。结果表明,在室内培养的条件下,单纯添加硝酸盐(增加至原海水硝酸盐浓度的5-20倍)可引起培养体系浮游生物量的变化,但不能引起海水pH及DIC、HCO-3含量的明显变化,对DIC而言,其变化率仅仅在1%以内,但可导致海水Pco2的相对明显升高,其最终结果导致海水碳汇强度的减弱,碳源强度的增加。 相似文献
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夏冬季三沙湾海水营养盐含量的时空变化特征及与环境因子的相关性 总被引：1，自引：0，他引：1
根据2012年8月和2013年1月对三沙湾海域开展的海域水质现场连续调查数据,阐述了无机氮和活性磷酸盐含量时空变化特征及其与环境因子的相关性.结果表明,三沙湾海域夏冬季无机氮含量范围分别为0.059～1.669、0.569～0.940 mg/dm^3,均值为0.582、0.676 mg/dm^3,活性磷酸盐含量范围分别为0.036～0.071、0.050～0.070 mg/dm^3,均值为0.056、0.060 mg/dm^3.无机氮和活性磷酸盐含量的高值区出现在陆源径流入海区及大量网箱养殖区,总体呈湾顶向湾口递减趋势,氮磷含量表层高于底层,冬季高于夏季,大部分海域都超过第四类海水水质标准.根据CN/CP比值评价结果显示,三沙湾大部分海域浮游植物的生长为氮限制.相关性分析表明,三沙湾海域无机氮与硝酸盐含量相关性极显著（r=0.989）,表明硝酸盐是无机氮的主要存在形态;无机氮还与盐度（r=-0.923）和温度（r=0.939）有极显著的相关性,论证了沿岸径流对三沙湾营养盐的输入有重要影响.活性磷酸盐与铵盐、亚硝酸盐含量存在显著的正相关.本次调研结果为三沙湾海域富营养化研究提供基础数据. 相似文献
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海水无机氮在监测过程中的质量保证＠葛仁英＠纪灵￥国家海洋局烟台海洋管区海水无机氮在监测过程中的质量保证葛仁英纪灵（国家海洋局烟台海洋管区２６４０００）在海洋监测中，无机氮（亚硝酸盐氮、硝酸盐氮、氨盐氮）是必测项目之一。海水中无机氮是海洋浮游植物繁殖、生长必... 相似文献
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探讨了壳寡糖及全乙酰壳寡糖的制备方法,通过正交实验考察了原料、温度、时间对降解产物的影响.制备了八种寡糖（八乙酰壳二糖、十一乙酰壳三糖、十四乙酰壳四糖和十七乙酰壳五糖,以及N,N′-二乙酰壳二糖、N,N′,N″-三乙酰壳三糖、N,N′,N″,N′′′四乙酰壳四糖和N,N′,N″,N′′′,N′′′′-五乙酰壳五糖）,并通过IR、NMR及MS等确定了其化学结构. 相似文献
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Coastal and estuarine habitat mapping, using LIDAR height and intensity and multi-spectral imagery 总被引：3，自引：1，他引：2
Guillem Chust Ibon Galparsoro ngel Borja Javier Franco Adolfo Uriarte 《Estuarine, Coastal and Shelf Science》2008,78(4):633-643
The airborne laser scanning LIDAR (LIght Detection And Ranging) provides high-resolution Digital Terrain Models (DTM) that have been applied recently to the characterization, quantification and monitoring of coastal environments. This study assesses the contribution of LIDAR altimetry and intensity data, topographically-derived features (slope and aspect), and multi-spectral imagery (three visible and a near-infrared band), to map coastal habitats in the Bidasoa estuary and its adjacent coastal area (Basque Country, northern Spain). The performance of high-resolution data sources was individually and jointly tested, with the maximum likelihood algorithm classifier in a rocky shore and a wetland zone; thus, including some of the most extended Cantabrian Sea littoral habitats, within the Bay of Biscay. The results show that reliability of coastal habitat classification was more enhanced with LIDAR-based DTM, compared with the other data sources: slope, aspect, intensity or near-infrared band. The addition of the DTM, to the three visible bands, produced gains of between 10% and 27% in the agreement measures, between the mapped and validation data (i.e. mean producer's and user's accuracy) for the two test sites. Raw LIDAR intensity images are only of limited value here, since they appeared heterogeneous and speckled. However, the enhanced Lee smoothing filter, applied to the LIDAR intensity, improved the overall accuracy measurements of the habitat classification, especially in the wetland zone; here, there were gains up to 7.9% in mean producer's and 11.6% in mean user's accuracy. This suggests that LIDAR can be useful for habitat mapping, when few data sources are available. The synergy between the LIDAR data, with multi-spectral bands, produced high accurate classifications (mean producer's accuracy: 92% for the 16 rocky habitats and 88% for the 11 wetland habitats). Fusion of the data enabled discrimination of intertidal communities, such as Corallina elongata, barnacles (Chthamalus spp.), and stands of Spartina alterniflora and Phragmites australis, which presented misclassification when conventional visible bands were used alone. All of these results were corroborated by the kappa coefficient of agreement. The high classification accuracy found here, selecting data sources, highlights the value of integrating LIDAR data with multi-spectral imagery for habitat mapping in the intertidal complex fringe. 相似文献
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Adsorption and desorption of proteins and polyamino acids by clay minerals and marine sediments 总被引：1，自引：0，他引：1
The adsorption and desorption of proteins and polyamino acids on illite, montmorillonite, goethite, and marine sediments was investigated. Three 14C-labeled hydrophilic proteins, Rubisco from C. reinhardtii, and GroEL and GroES from genetically modified Escherichia coli, were synthesized and purified for this study. The proteins were strongly and rapidly adsorbed by the clay minerals and marine sediments, and much of the adsorbed protein was not readily desorbed. Sodium dodecyl sulfate (SDS) extraction and separation by SDS-polyacrylamide gel electrophoresis (PAGE) and sucrose density gradients showed that Rubisco and GroEL were adsorbed on illite and sediments in their original forms. The apparent adsorption partition coefficients of the proteins were on the order of 102 l/kg on illite, 103–104 l/kg on goethite and montmorillonite, and 200 and 75 l/kg on Skan Bay and Resurrection Bay (Alaska) sediments, respectively. These partition coefficients are sufficiently large to permit sedimentary protein preservation via an adsorptive mechanism. Generally, basic polyamino acids had greater adsorption partition coefficients than acidic polyamino acids. Molecular size did not affect the electrostatic interaction between polyamino acids and mineral surfaces. Adsorption of bovine serum albumin (BSA) and negatively charged polyamino acids inhibited Rubisco adsorption, while positively charged cytochrome c and polyamino acids increased Rubisco adsorption. These results indicate that electrostatic interactions dominated in protein adsorption. 相似文献
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