深圳湾及邻近沿岸水域总溶解氮的分布、组成和来源及氮形态的转化

依据2000—2011年每月1次的调查资料,简要描述和讨论了深圳湾及邻近沿岸水域中总溶解氮(TDN)质量浓度的时空分布,并结合现场盐度、总凯氏氮、氨氮、亚硝酸盐氮和硝酸盐氮实测数据探讨TDN的组成和来源,以及溶解无机氮(DIN)和溶解有机氮(DON)之间的转化.结果表明,深圳湾和伶仃洋东部沿岸的TDN质量浓度分别为(2.870±2.150)mg·L-1和(0.679±0.405)mg·L-1.在深圳湾,由于受到周边陆源排放的影响,TDN质量浓度在丰水期较低,枯水期较高.在伶仃洋东部沿岸,由于受到珠江径流量的制约,TDN质量浓度呈明显的年周期循环特征,6月达到最高,为1.103 mg·L-1左右,而12月最低,为0.420 mg·L-1左右.12年研究期间,伶仃洋东部沿岸TDN质量浓度的年际变化略呈上升趋势,从0.560 mg·L-1上升至0.702 mg·L-1;深圳湾TDN质量浓度在2000—2004年呈上升趋势,从2.140 mg·L-1上升至3.577 mg·L-1,2005—2011年则呈下降趋势,从3.266 mg·L-1下降至2.280 mg·L-1.研究海区中的TDN具有"保守性",主要来自陆源排放.依二元混合质量平衡模式估算的伶仃洋东部沿岸TDN的陆源质量分数约为68.5%,而深圳湾的均大于87.0%.DIN是TDN的主要赋存形态.在氮从河口向海迁移期间,复杂的生物地球化学过程使DIN转化为DON的速率大于DON转化为DIN的速率.     

三峡库区香溪河秋末至中冬CO2和CH4分压特征分析

为揭示三峡库区支流库湾表层水体秋末至中冬CH_4和CO_2的分压特征及其影响因素,于2014年相应时间段在香溪河库湾每天定点定时采取表层水样,利用顶空气相色谱技术测定水中溶解CH_4和CO_2的浓度,通过亨利定律计算CH_4和CO_2的分压,并同步监测相关环境因子.结果表明,表层水体CH_4分压变化范围0.64~4.43 Pa,平均值为(1.69±0.94)Pa,CO_2分压变化范围49.90~868.91 Pa,平均值为(328.48±251.63)Pa.水体CO_2和CH_4分压的变化呈显著负相关(r=-0.618,P0.01),p CH_4和p CO_2与溶解氧、总磷、叶绿素a、p H水温和水位相关性明显,其中p CO_2与各环境因子的相关性较p CH_4更为密切.     

Speciation and Seasonal Variations of Dissolved Inorganic Arsenic in Jiaozhou Bay,North China

The distributions and biogeochemical cycles of arsenic in the aquatic environment have captured the interest of geochemists due to arsenic’s multiple chemical forms, the toxicity of certain arsenic species and large anthropogenic input. Seasonal variations in the dissolved inorganic arsenic concentration and speciation in Jiaozhou Bay, which is located on the west coast of the Yellow Sea in northern China, are presented here. Three cruises were carried out in Jiaozhou Bay under varying tidal regimes, one at neap tide and one at spring tide in August and one at spring tide in October of 2001. In addition to the transect surveys, the main sources of dissolved inorganic arsenate and arsenite in Jiaozhou Bay, including riverine input from five major tributary rivers, atmospheric dry and wet depositions, and groundwater and wastewater input, were collected in different seasons to estimate arsenic transport through different sources. The mean concentrations of total dissolved inorganic arsenic (TDIAs, As (V+III)) in Jiaozhou Bay were statistically comparable between summer and autumn, with higher concentrations at the northwest and northeast parts of the bay, reflecting human activities. The As (III)/TDIAs ratio ranged between 0.045 and 0.68, with an average of 0.16, implying that arsenate was the dominating species in Jiaozhou Bay. A preliminary box model was established to estimate the water-mass balance and arsenic budgets for Jiaozhou Bay, which demonstrated that river inputs and atmospheric depositions were the main sources of arsenic into Jiaozhou Bay. The concentrations of dissolved inorganic arsenic in Jiaozhou Bay have decreased in the last two decades. Compared with other areas in the world, the concentration of arsenic in Jiaozhou Bay remains at the natural level and this region can be characterized as a less disturbed area.     

Identification of anthropogenic effects and seasonality on water quality in Daya Bay, South China Sea

Thirteen water quality parameters from 12 monitoring stations were collected to study the effects caused by climate and anthropogenic activities on water quality in 2003 in Daya Bay, South China Sea. The data matrix has been built according to the results, which were analyzed by fuzzy c-mean cluster (FCM) and cluster analysis (CA). This analysis has identified anthropogenic effects and seasonal characters of water quality. The dry and wet seasonality have been demonstrated with FCM and CA. The precipitation and the Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on water quality in Daya Bay. In the spatial pattern, two groups have been classified with FCM and CA. Cluster I consisted of the sites S3, S8, S10 and S11 in the west and north coastal parts of Daya Bay. Cluster I is mainly related to anthropogenic activities such as fish-farming. Cluster II consisted of the rest of the stations in the center, east and south parts of Daya Bay. Cluster II is mainly related to seawater input from South China Sea. Thus, fuzzy c-mean cluster and cluster analysis can be an important tool for the successful characterization of regional-scale water quality.     

深圳蛇口港及其临近海域海水有机锡污染

以正己烷为萃取剂、四乙基硼化钠为衍生剂对海水样品进行同步化液-液萃取衍生反应,采用气象色谱-火焰光度检测法进行有机锡定性及定量分析,研究了深圳市蛇口港及其临近海域受有机锡污染的状况.结果显示,在所测定的海水中均检测出了三丁基锡、二丁基锡和一丁基锡化合物,三者的平均浓度分别为80、62和49 ng·L-1但本方法可能不适合三苯基锡的定性定量分析.港区个别站位海水三丁基锡浓度高达152 ng·L-1在深圳湾海水样品中还检测出了信号极强的多个未知峰,表明深圳蛇口港及临近海域海水有机锡的污染程度已经较为严重.蛇口港区有机锡污染可能与繁忙的航运以及珠江口水域存在的普遍性有机锡污染有关,而深圳湾有机锡污染一方面可能是来自蛇口港区有机锡污染的扩散,另一方面可能来自深圳河的排污.位于深圳湾的国家级红树林及鸟类自然保护区是一个对生物多样性的维持及侯鸟的保护都极为 重要的湿地生态系统,该海区受有机锡污染问题需要引起高度重视,长期的有机锡污染必将对该湿地生态系统造成严重危害.     

大亚湾养殖区营养盐状况分析与评价

研究了1997年春季大亚湾大鹏澳海域及1997～1998年度和1998～2000年春季澳头海域营养盐及其他水化参数的变化。大鹏澳和澳头海域平均DIN含量分别为52.37、115.07μg/L,DIP为5.33、9.19μg/L,DSi为351.81、1068.3μg/L。大鹏澳海域营养状态质量指数(NQI)值多在1.0以下,平均0.97;1998～2000年春澳头海域NQI平均值分别为1.94、1.63、1.51。从1997年澳头海域水质状况来看,春夏季节水质污染程度较高,秋冬季节较低。研究结果表明:大亚湾海域整体水质良好,而且大鹏澳海域水质优于澳头海域,但近岸海区和养殖区已受到一定程度的污染,水质已接近中营养型水平。     

胶州湾表层水体中邻苯二甲酸酯的污染特征和生态风险

以胶州湾为研究区域,选取15种常用邻苯二甲酸酯（phthalate esters,PAEs）作为检测目标,采用搅拌棒吸附萃取-气相色谱质谱联用的方法,于2015年8月和11月以及2016年1月对胶州湾开展3次大面积调查,检测分析了胶州湾表层水体中PAEs的含量、组成、空间分布和季节变化,同时对胶州湾水体中PAEs进行了风险评价.结果表明：①2015年8月和11月、2016年1月胶州湾表层海水中PAEs的总浓度范围分别为3.63~21.20、2.24~12.60和0.01~4.15μg·L^-1,平均浓度分别为11.10、5.26和0.80 μg·L^-1.②受入海径流和洋流影响,胶州湾表层水体中PAEs浓度表现出近岸高,远岸低,且总体东岸浓度高于西岸.与国内外其他研究相比,胶州湾表层水体中PAEs含量处于中等水平,但在海洋中属于污染较严重的海域.33个季节PAEs浓度分布差异较大,受降雨量等因素影响整体呈现夏季 > 秋季 > 冬季的趋势,③个季节主要检出种类均为DBP、BBP和DEHP.④生态风险评估结果表明,胶州湾各站位DBP的风险商值（RQ）均大于1,即生态风险较大,其他PAEs（RQ<1）风险较小.PAEs已成为胶州湾中一类具有潜在威胁的有机污染物,其在环境中的行为和生态危害仍需进一步研究.     

Evolution of nutrient structure and phytoplankton composition in the Jiaozhou Bay ecosystem

IntroductionThehealthofcoastalenvironmenthasbeendrawingthepeople′sattentionsallovertheworld.Thebudgetsofnutrientsinthisareaareoneofthemainfocuses.Althoughnitrogenistheprimarylimitingnutrientformarinephytoplanktononaglobalbasis,exceptionsareoftenseenandparticularkindsofnutrientlimitationseemtobesituationspecificinmostcases.Inrecentyears,phosphorushasbeenfrequentlyreportedtobethelimitingnutrientforphytoplanktonproductivityincoastalwaterswithhighinputfromlandrunoff(Bonin,1989;Mahoney,1989;Heis…     

大亚湾石化排污海域重金属污染及生态风险评价

为了解大亚湾石化排污区海域重金属污染现状及其潜在生态风险,对该湾的海水、表层沉积物和生物(鱼)体中7种重金属(Zn、Pb、Cu、Cd、Cr、As、Hg)含量及空间分布进行了研究,并分别采用综合污染指数法和生态风险指数法对海水和表层沉积物重金属污染程度及潜在生态危害进行了评价.结果表明,2011~2012年海水重金属含量较低,除部分站位Zn和Pb超过海水水质第一类标准外,未出现明显的重金属污染.海水重金属综合污染指数均值丰水期(0.72)>枯水期(0.38),表层沉积物重金属综合污染指数均值枯水期(7.77)>丰水期(5.70),枯水期表层沉积物重金属污染因子为Hg,其次为As和Zn;丰水期表层沉积物重金属污染因子为Hg,其次为Zn和Cu.调查海域丰水期和枯水期间采集到的生物(鱼)体内各种重金属均未超标.重金属含量的相关性分析表明,不同时期大亚湾石化排污区重金属间的相关程度差异明显.枯水期调查海域沉积物重金属潜在生态风险指数RI(129.20)>丰水期(102.86),枯水期有25%的站位出现高警级风险.调查海域沉积物重金属潜在生态风险在丰水期是远岸海域高于沿岸海域,湾口高于湾顶;而在枯水期则相反.Hg对大亚湾石化排污区海域存在强潜在生态风险,其他6种重金属均为轻微潜在生态风险.     

三峡水库蓄泄水过程对香溪河库湾水华影响的对比分析

通过对比分析蓄、泄水期间三峡水库干流及支流香溪河库湾的水流、水温、浊度、营养盐等指标,研究了蓄、泄水过程中控制库湾水华的主要因子.结果表明,泄水过程中香溪河库湾叶绿素a浓度显著大于蓄水过程,水华暴发强度差别显著.蓄、泄水过程中以透明度的差异最大,其次依次为表层流速、表底温差、混合层深度、氮磷比、浊度、总氮、水体稳定系数、真光层/混合层深度比等.泄水期间各因子对叶绿素a浓度不存在单一限制作用,藻类生长受各因子的协同作用影响,在观测时段内泄水过程中各因子的变化对藻类生长的限制并不显著;而蓄水期间强烈的倒灌异重流作用加剧了库湾水体的垂向掺混,增大混合层深度,较小的真光层与混合层深度比对藻类生长起到显著的抑制作用.