福建省主要江河入海口水质状况及其变化趋势研究

根据2010年-2013年福建省主要江河入海口每月一次的监测调查资料,评价2013年的入海口水质现状和富营养化程度,分析2013年的月变化和2010年-2013年的年际变化.结果表明,2013年福建省11条主要江河入海口水质均为劣四类海水水质,富营养化程度高且磷限制特征明显.入海口的石油类和化学需氧量的月变化和年变化受降雨影响大,高值区主要在降雨多的月份和年份,入海口的无机氮和活性磷酸盐含量受水中浮游植物和降雨量双重影响,夏秋低,春冬高,年际变化受年际降雨量变化影响有所波动,但大部分入海口的无机氮和活性磷酸盐含量呈略微上升的趋势.     

INVESTIGATION OF TURBIDITY MAXIMUM IN A MESOTIDAL ESTUARY,TAIWAN1

ABSTRACT: To comprehend the distributions of salinity, temperature, and suspended sediment in the Danshuei River estuary in Taiwan, monthly field surveys were conducted in 2003. These included several high and low slackwater surveys and intensive surveys. The results show that the Danshuei River estuary is predominately a partially mixed estuary. The highest concentration of suspended sediment is typically observed at the Chung‐Hsin Bridge, the most upstream sampling station. The suspended sediment concentration exhibits a general decreasing trend in the downstream direction. It may be concluded that the sediments mostly come from the upstream reach. A locally high concentration of suspended sediment is found at the Kuan‐Du station because of the local deep channel bathymetry and two‐layered estuarine circulation. A vertical two‐dimensional hydrodynamic and sediment transport model is applied to investigate the tidally averaged salinity distribution, residual circulation, and suspended sediment concentration. The modeling results reveal that, under the Q₇₅ flow condition (i.e., low flow), a turbidity maximum occurs at the Kuan‐Du station due to the strong estuarine circulation. The model simulation with a much higher river flow condition results in a weaker residual circulation and weaker turbidity maximum.     

Assessment of contamination by heavy metals and petroleum hydrocarbons in sediments of Montevideo Harbour (Uruguay)

As part of the first environmental assessment within Montevideo Harbour, in summer and winter of 1998, sediments samples were collected at eight locations to determine the spatial distribution of anthropogenic pollutants. Muddy sediments with high organic matter content dominate the study area. Heavy metal levels indicated that sediments were highly polluted with Zn (overall mean: 312+/-102 microg g(-1) dry sediment), Pb (85+/-31), Cu (89+/-25), Cr (162+/-62), and Hg (0.63+/-0.3) and moderately with Ni (30+/-2) and Ag (1.2+/-0.4). Depending on location and season, aliphatic hydrocarbons reached from 21 to 120 microg g(-1), while the unresolved complex mixture represented up to 76% of the total aliphatic fraction. Total PAH concentrations ranged from 1.56 to 90.44 microg g(-1); except at one location, petroleum derivatives were identified as main local source. The results pointed out that almost all the harbour area presented some substances that can cause adverse biological effects, especially in the inner region where all metals are above PEL levels. Principal components analysis confirmed that the inner harbour region is most severely affected by the pollutants and it was possible to differentiate three regions according to their environmental quality.     

辽河口粪便污染指示菌的时空分布特征

2013年分别于夏季和秋季对辽河口海域的粪便污染指示菌(总大肠菌群、粪大肠菌群和肠球菌)及环境、水化学要素进行分析,研究粪便污染指示菌在海水中的数量、分布特征及其与环境、水化学指标间的相关性,在此基础上,选取河口地区合适的粪便污染指示菌.结果表明:夏季总大肠菌群数量在1.7×105~6.2×106CFU·L-1之间,粪大肠菌群数量在5.0×102~8.7×104CFU·L-1之间,肠球菌数量在1.0×101~2.5×102CFU·L-1之间;秋季总大肠菌群数量在5.0×102~1.1×105CFU·L-1之间,粪大肠菌群数量在4.0×102~1.0×103CFU·L-1之间,肠球菌数量在3~95 CFU·L-1之间.总大肠菌群、粪大肠菌群和肠球菌的数量变化与环境指标之间有着密切联系,特别是与盐度存在显著相关性;粪大肠菌群、肠球菌与水化学指标Si O4-4-Si、NH+4-N、TP和COD之间均存在显著相关性;其中粪大肠菌群与SiO4-4-Si和TP的相关性系数均大于0.742(p0.01),肠球菌与TP和COD的相关性系数均大于0.742.实验结果表明,辽河口粪便污染指示菌的数量在夏季高于秋季,近岸高于远海,其中粪大肠菌群和肠球菌的数量、分布特征与陆源污染物特别是氮磷的输入量密切相关,而且两者之间呈显著正相关关系.粪大肠菌群与肠球菌在一定程度上可以反映河口粪便污染情况,建议采用粪大肠菌群与肠球菌作为河口粪便污染的指示菌.     

闽江河口互花米草海向入侵对湿地土壤nirS型反硝化微生物群落结构及多样性的影响

2020年秋季,在闽江河口鳝鱼滩东部的互花米草分布区,由陆向海方向选择互花米草海向入侵前的光滩(MF)、入侵1～2年的互花米草湿地(SAN)和入侵6～7年的互花米草湿地(SA)为研究对象.基于高通量测序技术,探讨了互花米草海向入侵对土壤nir S型反硝化微生物群落结构及多样性的影响.结果表明,变形菌门(Proteobacteria)均是互花米草不同入侵阶段土壤中nir S型反硝化微生物的优势门(90.41%～97.36%),其次是厚壁菌门(Firmicutes)和放线菌门(Actinobacteria),三者在SAN和MF土壤中的丰度均与SA存在显著差异(p<0.05).不同入侵阶段土壤中共有的nir S型反硝化细菌属为假单胞菌属(Pseudomonas)、芽孢杆菌属(Bacillus)、偶氮弧菌属(Azoarcus)、陶厄氏菌属(Thauera)、Sulfurifustis属、副球菌属(Paracoccus)、鲁杰氏菌属(Ruegeria)、红肠命菌属(Rubrivivax)、趋磁螺菌属(Magnetospirillum)和福格斯氏菌属(Vogesella),其中,假单胞菌属是...     

九龙江口微塑料与抗生素抗性基因污染的分布特征

河口区域普遍存在微塑料（MPs）和抗生素抗性基因（ARGs）污染,同时微塑料还可能富集ARGs,从而扩大ARGs的传播范围.本研究以福建省九龙江口为调查区域,首次分析了九龙江口不同采样点水样以及沉积物中的MPs分布特征,同时测定各样品中8种常见的ARGs丰度,并对二者之间的丰度进行相关性分析.结果表明：①九龙江河口水环境中微塑数浓度范围为2~66 n ·L^-1,沉积物中含量范围（以dw计）为8~85 n ·kg^-1,85%以上的微塑料粒径在1 mm以下,微塑料材质主要为聚乙烯（PE）、聚丙烯（PP）和聚苯乙烯（PS）;②九龙江河口优势的ARGs为四环素类抗性基因tetC和tetG以及磺胺类抗性基因sul2,水中ARGs丰度随盐度增加呈递减趋势;③九龙江水体中MPs浓度、ARGs相对丰度和一类整合子基因intI1丰度呈两两正相关性,说明微塑料可能促进了水体中ARGs的传播和水平基因转移（HGT）.     

闽江口秋茄红树林凋落物产量及分解动态

于2017年以闽江口粗芦岛秋茄(Kandelia obovata)红树林为研究对象,分别采用凋落物收集框和分解袋法,研究秋茄凋落物产量及其碳(C)、氮(N)、磷(P)含量月动态及凋落叶分解过程中C、N、P含量与水解酶活性.结果表明:①秋茄凋落物年产量为618.79 g·m~(-2)·a~(-1),其中,叶占61.2%,果、枝和花分别占23.7%、10.5%和4.6%.②凋落叶总氮(TN)含量8月显著高于其他月份(p0.05),而TP含量在1—3月显著高于其他月份;C/N在8月显著低于其他月份(p0.05),而C/P及N/P在9月显著升高(p0.05).③在凋落叶分解过程中,C、N、P含量及其化学计量比随时间存在明显差异(p0.01),并且地上组TC、TN、C/N和C/P明显不同于地下组(p0.05).④在分解过程中,4种水解酶随时间存在明显差异(p0.01).⑤凋落叶酸性磷酸酶活性与土壤温度、电导率和凋落叶TP含量存在显著相关关系(p0.01).这些结果说明,秋茄凋落物产量及元素含量随季节变化存在明显差异;沉积作用对凋落叶分解过程中元素含量有显著影响,水解酶活性主要受凋落叶元素含量和土壤环境因子的控制.     

螃蟹活动对闽江河口互花米草沼泽湿地土壤温室气体排放通量的影响

于2015年1月（冬季）、4月（春季）、6月（夏季）和9月（秋季）,以闽江河口互花米草沼泽湿地为研究区,采用静态箱与气相色谱结合的方法,研究螃蟹对湿地土壤CO₂、CH₄和N₂O排放通量及综合增温潜势的影响。研究表明：温室气体排放季节变化较为显著,CO₂、CH₄排放通量最大值均出现在夏季,N₂O排放通量最大值出现在秋季,CO₂、CH₄和N₂O排放通量最小值均出现在春季。与无螃蟹组相比,高潮滩和中潮滩螃蟹组CO₂、CH₄和N₂O排放通量均值都增大,其中高潮滩螃蟹组CO₂、CH₄和N₂O排放通量依次增大了46.36%、66.67%和69.66%,中潮滩螃蟹组CO₂、CH₄和N₂O排放通量依次增大了53.57%、142.97%、73.08%。相关性分析结果表明：土壤CO₂排放通量与土壤温度显著正相关（n=96,p＜0.05）,CH₄和N₂O排放通量与土壤温度显著正相关（n=96,p＜0.01）;N₂O排放通量与土壤pH显著正相关（n=96,p＜0.01）,与土壤含水量显著正相关（n=96,p＜0.05）。综上所述,螃蟹活动对闽江河口互花米草沼泽湿地土壤的干扰促进了温室气体的排放,为有效调节湿地碳、氮固持作用和湿地生态系统科学管理提供了参考。     

Heavy metals associated with reduced sulfur in sediments from different deposition environments in the Pearl River estuary, China

Distribution of acid volatile sulfur (AVS) and the simultaneously extracted metals (SEM: Cu, Pb, Zn, Cd, Ni) in sediment profiles has been studied at five sites in Pearl River estuary, China. Of the five sampling locations, Nos.1 and 2 are in the middle shoal, Nos.3 and 4 in the west shoal and No. 5 locates to the south of the estuary. The AVS content in the sediments of the middle shoal varies in a small range (0.25–4.06 μmol g⁻¹), while that of west shoal increases with depth from 0 to ultimately 26.09 μmol g⁻¹. The SEM concentration in the sediment profiles at location Nos. 1, 2 and 5 is generally in the range of 0.95±0.2 μmol g⁻¹ with a slight upward increase, while that in the sediment of west shallows are much higher (1.43–2.42 μmol g⁻¹) with a significant upward increase, especially in the upper layer of ca. 15 cm. The observed upward increase of SEM content at all the sites implies that heavy metal contamination of sediment in the Pearl River estuary is increasing. Calculations of the excess heavy metal content which is defined by SEM-AVS molar difference suggests that the upper sediment in the Pearl River estuary, especially on the west shallows, could be a source of heavy metal contaminants and may cause toxicity to the benthos. The site-specific distribution patterns in the AVS and SEM profiles were interpreted according to the hydrogeochemistry of deposition environments.     

Metal bioaccumulation and metallothionein concentrations in larvae of Crassostrea gigas

Larval stages of bivalve molluscs are highly sensitive to pollutants. Oysters from a hatchery from Normandy (English Channel) were induced to spawn, and fertilized eggs were exposed to copper or cadmium for 24 h. Metal accumulation (from 0.125 to 5 microg Cu L(-1) and from 25 to 200 microg Cd L(-1)) and MT concentrations were measured in larvae. Compared to controls, larvae accumulated copper and cadmium with an increase in MT concentrations particularly with cadmium (i.e. 130.96 ng Cu (mg protein)(-1) and 12.69 microg MT (mg protein)(-1) at 1 microg Cu L(-1) versus 23.19 ng Cu (mg protein)(-1) and 8.92 microg MT (mg protein)(-1) in control larvae; 334.3 ng Cd (mg protein)(-1) and 11.70 microg MT (mg protein)(-1) at 200 microg Cd L(-1) versus 0.87 ng Cd (mg protein)(-1) and 4.60 microg MT (mg protein)(-1) in control larvae). Larvae were also obtained from oysters of a clean area (Arcachon Bay) and a polluted zone (Bidassoa estuary) and exposed to copper in the laboratory, their MT concentration was measured as well as biomarkers of oxidative stress. Biomarker responses and sensitivity to copper for the larvae from Arcachon oysters were higher than for those from Bidassoa.