湛江东海岛潮间带沉积物硫化物(AVS)和重金属(SEM)及其生物毒效性评估(英文)

对湛江东海岛潮间带表层沉积物中酸可挥发性硫化物(AVS)和同步提取重金属(SEM)的含量及其分布进行了研究。研究表明,东海岛潮间带表层沉积物中AVS含量夏季平均为0.449μ mol/g,冬季为1.816μ mol/g,大多数站位AVS含量冬季高于夏季;AVS平均含量总体呈南、北区较高,东、西区较低的区域分布规律。潮区沉积物可提取重金属SEM总量夏季在0.56μ mol/g~4.60μ mol/g之间,冬季处于0.65μ mol/g~2.21μ mol/g之间;各重金属平均含量大小为ZnCrPbCuCd,其中Cd含量占SEM总量不到1%,Zn含量则在70%以上,SEMZn是控制着SEM分布的主要模式。联合利用(∑SEM/AVS)与(∑SEM-AVS)法和生物毒性阈值法综合评估重金属对沉积环境的影响,东海岛潮间带大部分区域沉积物中(∑SEM-AVS)处于0~5之间,重金属潜在生物毒性较强的区域为通明海区(7号站和8号站所在),具有较强潜在生物毒性的重金属为夏季通明海区的Zn。     

湛江湾沉积物中酸可挥发性硫和重金属含量分布及重金属生态风险评价

测定了湛江湾海域20个站位表层沉积物中的酸可挥发性硫（AVS）、同步浸提重金属（SEM）、TOC含量和Eh值,对AVS、SEM含量的平面分布及AVS与SEM、TOC含量、Eh值的相互关系进行了分析.结果表明：该海域表层沉积物中AVS含量范围为0.004～0.547μmol/g,平均值为0.155μmol/g,SEM含量范围为2.10～4.27μmol/g,平均值为3.32μmol/g,相对其他海域湛江湾海域沉积物表现出AVS含量较低,SEM含量较高的特征.AVS与SEM含量平面分布较一致,湾顶的含量都较高,含量均值分别为0.361和3.52μmol/g,特呈岛以南到湾口呈逐渐减小的明显趋势.调查海域沉积物AVS与TOC含量呈显著正相关,与Eh值呈显著负相关,说明高有机质含量、低氧化还原电位沉积环境有利于AVS的生成.20个站位CSEM5-CAVS的差值均为0〈（CSEM5-CAVS）〈5,说明该海域可能存在重金属的中等毒性生态风险.     

洋山海洋倾倒区倾倒前后沉积物中酸可挥发性硫化物与重金属的比较分析

为了更清楚认识洋山海洋倾倒区海域沉积物的污染状况,测定了该海域倾倒前后表层沉积物中酸可挥发性硫化物(AVS)、酸可提取重金属(SEM)的含量,并对AVS、ΣSEM及ΣSEM-AVS差值的平面分布进行了分析。结果表明,该倾倒区及周边海域倾倒前、中、后表层沉积物中AVS含量分别为0.55~2.62,0.83~1.65和0.51~1.23 μmol·g^-1,倾倒后AVS含量呈下降态势,倾倒区AVS含量高于周边海域;ΣSEM倾倒前、中、后平均含量分别为2.80,2.79和2.60 μmol·g^-1,倾倒后ΣSEM含量略呈下降态势,往倾倒区方向富集;从单个重金属对ΣSEM的贡献率来看,Zn＞Cr＞Cu＞Pb＞Cd,SEM_Zn基本在35％以上,SEM_Cr基本在20％以上,而SEM_Cd均在1％以下,ΣSEM分布形态主要受Zn和Cr的控制;ΣSEM-AVS差值均大于0,且在倾倒区其ΣSEM-AVS值低于周边海域,说明倾倒区海域沉积物中重金属对生物可能有一定毒性。     

品清湖沉积物酸可挥发性硫化物与重金属生物毒效性研究

测定了广东汕尾品清湖海域7个站位表层沉积物样品的酸可挥发性硫化物(AVS)和同步浸提重金属(SEM)质量摩尔浓度,对AVS、SEM及其比值以及分布进行了分析。结果表明,该海域表层沉积物AVS质量摩尔浓度范围为0.315～1.635μmol.g-1;SEM质量摩尔浓度分布范围为1.332～2.424μmol.g-1。通过分析,品清湖表层沉积物中Cu和Pb的生物有效性较高,对底栖生物存在潜在的毒性效应,其它单个重金属不会对底栖生物产生毒性效应。     

珠江口沉积物酸挥发性硫化物与重金属生物毒性的研究

研究了2003年10月采于珠江口5个站位的沉积物剖面酸挥发性硫化物(AVS)和同时提取的重金属(SEM:Pb,Zn,Cu,Cd,Ni)。其中,站位1、2位于中滩,其沉积物的AVS含量变化范围较小,为0.25—4.06μmol.g-1;站位3、4位于西滩,其沉积物的AVS含量变化范围较大,为0—26.09μmol.g-1。中滩和西滩沉积物的AVS含量均随深度增加。西滩表层沉积物的AVS含量接近于零,这可能与该水域较强的底层流和沉积物的再悬浮作用有关。站位5位于珠江口外侧,其表层沉积物的AVS含量相对较高,且垂向变化较小,可能是还原性沉积物间歇性再悬浮后重新沉积的结果。站位1、2和5沉积物中同时提取的重金属含量大体在0.95±0.2μmol.g-1范围内,随深度增加略呈下降趋势;而西滩沉积物重金属含量相对较高,为1.43—2.42μmol.g-1,且在一定深度范围内随深度增加呈明显下降的趋势,表明珠江口西滩沉积物中的重金属污染有加重的趋势。对AVS/SEM摩尔比值和单个金属的毒性效应研究显示,珠江口内尤其是西滩的表层沉积物存在重金属污染,对其中生活的底栖生物具有潜在的毒性效应。     

潮间带沉积物中重金属的AVS归一化研究

采集胶州湾河套镇养殖区潮间带高、中、低潮带的沉积物样品 ,将重金属 AVS归一化法应用于粘土质潮间带沉积物研究 ,测定了酸可挥发硫 (AVS)和酸化过程中溶解释放的重金属 (SEM) ,并根据 SEM与 AVS的摩尔浓度关系评价二价重金属 (Cu、Pb、Zn、Cd、Ni)的化学活性和生物可获得性。结果表明 :河套镇养殖区除各潮带表层 0～ 2 cm外 ,SEM/ AVS均小于 1,重金属的生物活性小 ,不会对养殖的底栖生物造成影响。 8cm以下 AVS平均含量高潮带 >中潮带 >低潮带 ,在同一潮位 AVS随深度增加而增加 ;相同潮位的 SEM垂直变化趋势相同     

珠江口海岸带沉积物中酸可挥发性硫化物与重金属生物毒效性研究

对珠江口淇澳岛附近2个站(QA-2、QA-5)柱状沉积物中酸可挥发性硫化物(AVS)和同步提取重金属(SEM)的垂直分布规律进行了研究。研究表明,AVS在2个站沉积物中的质量摩尔浓度分别为3.44～13.13μmol/g和11.67～15.39μmol/g。QA-2站沉积物中AVS的质量摩尔浓度随深度增加,QA-5站AVS的质量摩尔浓度垂直剖面上没有明显的变化趋势,反映了不同沉积环境对AVS质量摩尔浓度分布特征的影响。2个站的SEM的质量摩尔浓度在沉积物垂直剖面上都随深度增加逐渐减小,这是因为珠江三角洲工业和城市的发展、污染物排放增加导致了重金属在沉积物中的累积。QA-2站表层沉积物(0～5 cm)SEM/AVS>1,表明可能存在重金属的生物毒效应;同时,SEM中Cu和Cd的质量摩尔浓度超过了它们的重金属浓度阈值(TEL),有可能产生重金属毒性作用;QA-2站5 cm以下和QA-5站沉积柱中SEM/AVS<1,不存在重金属的生物毒效性。     

湛江东海岛潮间带表层沉积物粒度的分布及与环境要素的相关性

于2011年7月对湛江东海岛潮间带表层沉积物粒度及沉积环境要素进行了调查和分析.结果表明,东海岛潮间带表层沉积物可分为4种类型,即砂、粉砂质砂、砂质粉砂、粘土质粉砂,砂和粉砂质砂是东海岛潮间带沉积物主要类型.其中,湛江湾区(Ⅰ区)、龙海天区(Ⅱ区)、雷州湾区(Ⅲ区)等3区的主要沉积类型是砂,粉砂是通明海区(Ⅳ区)的主要沉积类型.东海岛各区潮间带表层沉积物平均粒径在0.023~0.342 mm(1.55~5.46φ)之间,平均值为0.092 mm(3.45φ),各潮区颗粒大小总体表现为高潮区中潮区低潮区,且从西部东海大堤两侧的较小值沿东海岛南北两侧逐渐增大为东区的较大值.东海岛龙海天潮间带表层沉积物分选程度为中等至差之间,包含了从显著负偏态至正偏态的大多数类型,峰态多为宽平型和尖锐型.东海岛各区潮间带表层沉积物类型及其粒度分布特征是该岛沿岸潮流动力环境差异的直接体现,并直接影响沉积区的理化性质,表现为在沉积颗粒大的沉积区p H和CFe3+/CFe2+较高、有机物和硫化物含量较低,沉积颗粒较小的区域各环境因子变化规律相反.     

胶州湾李村河口沉积物中酸可溶硫化物与活性金属分布特征

对胶州湾李村河口9个短柱状样沉积物中活性金属、AVS和有机质含量等参数进行了分析.其中AVS含量:198.4～0.4 μmol/g,平均35.8μmol/g.大部分样品活性金属含量具有 Fe > Zn > Cu > Cr >V > Ni > Pb > Co > Cd 的顺序.活性重金属 Zn, Cu, Cr, V, Ni, Pb, Co, Cd 含量之和 ( ΣM ) 为:0.53～17.39 μmol/g.通过对所测数据分析发现,大多数活性金属间具有较好的相关性,反映了它们具有相同的来源或相似的早期成岩地球化学特征.近河口区沉积物的地球化学特征与远河口区差异明显:近河口区底层水为还原环境,AVS 形成的制约因素是活性铁的可获得性,而活性重金属的分布受到AVS的控制并主要以金属硫化物或硫化物吸附态的形式存在,AVS 仍具有较大的吸附重金属的潜力,同时硫化物中重金属再次释放造成二次污染的潜在性也较大;而在离河口稍远的海域,沉积物中 AVS 形成的控制因素是有机质的供给和环境氧化还原状态的变化,活性重金属主要以铁氧化物结合态存在,表层沉积物中重金属的环境敏感性及生物有效性都较高.     

冷扩散法提取沉积物中的酸可溶硫化物及其在中国边缘海区的应用

为了快速而有效地对中国边缘海区沉积物中的酸可溶硫化物(AVS)进行研究,冷扩散法被引入。用冷扩散法提取不同体积硫化物溶液中的AVS,所得到的AVS含量与所加溶液体积的相关性较好,说明此方法具有较好的提取效果。在中国边缘海不同典型海域的浅表层沉积物中,利用冷扩散法对AVS进行了分析:胶州湾李村河口AVS的浓度在0.4~120.1μmol/g之间;南黄海西北部陆架在0~11.1μmol/g之间;南海北部陆坡一柱状样沉积物中多数样品<1μmol/g。结果显示不同典型海域沉积物中AVS的分布差别较大,符合不同环境沉积物中AVS含量的一般规律。因此冷扩散法作为一种有效的AVS提取方法,值得在研究中使用与推广。     

Coral Associations, Biocorrosion, and Space Competition in Pedum spondyloideum (Gmelin) (Pectinacea, Bivalvia)

Abstract. In the northern Red Sea several genera of sclcractinian corals arc used as hosts by Pedum spondyloideum. High population densities lead to space competition. The bivalves use chemical means to interact with each other and with their host corals. Due to dorsal attachment and predominantly ventral growth - to keep pace with coral growth - biocorrosion is less obvious, than in Lilhophuga.     

Biogeography, Taxonomical Status and Ecology of Alcyonium (Parerythropodium) coralloides (PALLAS, 1766)

Abstract. Ecology and morphology of Alcyonium (Parerythropodium) coralloides were studied in different sites of the Eastern Atlantic and the Mediterranean. The species is extremely variable in size, colony shape and colour. In the Mediterranean population, encrusting red colonies are mostly encountered, although lobate colonies also exist. White and pink colonies are considered mutants, which tolerate the stable environment of deeper habitats better than the conditions encountered in shallow biotopes. Mediterranean colonies are dioecious and reproduce sexually. In the Eastern Atlantic, lobate pink colonies are the most common form, and show little variability. These (at least partly) parthenogenic populations are considered offspring from stray larvae from more southern regions. This explains the rather patchy distribution of the Atlantic populations, as compared to the widespread distribution throughout the entire Western Basin of the Mediterranean and the Adriatic Sea. A study of the most important systematic characters of the species (growth form, sclerites and solenial network) leads to the conclusion that coralloides belongs to the genus Alcyonium. As a result, coralloides being its type-species, the genus Parerythropodium will have to be suppressed.     

The Biology of Upogebia pusilla (PETAGNA) (Decapoda, Thalassinidea)

Abstract. The distribution of the thalassinidean shrimp Upogebia pusilla was studied at four sites in the North Adriatic Sea: 1) a tidal flat in the lagoon of Grado, 2) a tidal flat at Lido di Staranzano near the mouth of the Isonzo, 3) a mud flat seawards of a salt marsh in a protected bay north of Rovinj, and 4) a sublittoral station in 6m depth near Aurisina. Information on grain size distribution, organic content, amount of debris, redox profiles and pH of sediment as well as temperature and salinity is given. Density, as determined by hole counts and a hole: burrow relationship derived from resin casting, generally increased with increasing water depth in the intertidal. The upper limits ranged between +10cm (Rovinj) and -20cm (Grado); densities between mean water and low water level varied strongly due to microtopography and macrophyte cover. Maximum densities in the intertidal ranged from 189 (Grado) to 2420 (Rovinj, juveniles) animals m². Shrimp density at the sublittoral station ranged between 80 and 230 m"². The zonation of the Upogebiidae and Callianassidae with respect to environmental parameters is discussed.     

Reproductive biology of Parazoanthus axinellae (Schmidt, 1862) and Savalia savaglia (Bertoloni, 1819) (Cnidaria,Zoantharia) from the NW Mediterranean coast

Despite the wide distribution of zoanthids, little is known about their pattern of reproduction. Here we investigate the reproductive biology of two Mediterranean species, the common Parazoanthus axinellae (Schmidt) and the rare Savalia savaglia (Bertoloni). For both species, samples were collected during an annual cycle, from January to December 2005, in the Western Mediterranean (Ligurian Sea, Italy). Both species are gonochoric. In P. axinellae the sex‐ratio (n colonies = 30) showed a slight predominance of male colonies (M/F = 1.35), whereas in the population of S. savaglia (n colonies = 15) a predominance of females was found (M/F = 0.3). In P. axinellae the first gametocytes were visible in March, whereas in S. savaglia they became visible in May. Both species reproduce at the end of autumn when seawater temperature begins to decrease. Parazoanthus axinellae (10 m depth) spawns eggs and sperms in November, whereas S. savaglia (67 m depth) spawns in December. In P. axinellae sexes were segregated on a rocky wall, with males occurring deeper, whereas male and female colonies of S. savaglia were irregularly dispersed in the population. The maximum number of oocytes differed between the species, being higher in P. axinellae than in S. savaglia.     

The Biology of Upogebia pusilla (PETAGNA) (Decapoda, Thalassinidea)

Abstract. Populations of the thalassinidean shrimp Upogebia pusilla were studied on tidal flats in the Northern Adriatic Sea. Biometric analysis showed a sexual dimorphism, especially in propodus size. Size frequency distributions revealed the presence of large animals during all seasons; recruitment by juveniles occurred in autumn. Moult intervals and moult increments were determined in the laboratory and used to generate growth curves which were compared with those calculated from size frequency distributions. The life span of U, pusilla is over 5 years. Ovigerous females occurred between March and September. Egg numbers were high in spring, lower in summer and increased with body size. The incubation time of embryos was 35 days; a female produces an estimated number of three egg batches during the breeding season. A total annual production of 994 kJ was estimated for a theoretical population of 100 animals; 13.5 % is spent for somatic growth, 31 % for egg production of females, and 55.2% is lost as exuviae. The population structures, growth and breeding patterns, as well as embryonic and larval development within the Upogebiidae and Callianassidae are discussed.     

Ibla cumingi (Crustacea, Cirripedia) -A Gonochoristic Species (Anatomy, Dwarfing and Systematic Implications)

Abstract. Ibla cumingi (Crustacea, Cirripedia) is a gonochoristic species with dwarf males. The anatomy of both sexes is described and compared with that of other Cirripedia s. str. Systematic implications on the basis of anatomy and biology are given. The degree of dwarfing in the male and the possible cause and way of reduction are discussed.     

Polymorphic Zooids in Deitaic Species Populations of Conopeum seurati (CANU, 1928) (Bryozoa, Cheilostomata)

Abstract. Deltaic populations of Conopeum seurati from diverse environmental settings have variable phenotypes related to strong competitive regimes and to dissolved oxygen minima. Under extremely stressful conditions, the poorly canalized phenotype of C. seurati displays new additional features such as kleistozooids ( kleistós = closed) and chaotic celleporoid layers. Kleistozooids are clearly distinguishable polymorphs characterized by the presence of a compact, imperforate frontal membrane and by a strongly reduced lumen of the "opesium". They commonly aggregate in clusters of regularly-arranged individuals that store a large quantity of proteic material. The inferred function of these cell-like structures is to supply nutrients for basic colony activities. Celleporoid layers are, possibly, a developmental relaxation of the colony of C. seurati for a more efficient use of space in competitive interactions.
Both celleporoid layers and kleistozooids reveal the magnitude of intracolony variability of a widespread opportunistic bryozoan species.     

Larval shell development of the toheroa,Paphies ventricosa (Gray, 1843) (Mactracea: Mesodesmatidae)

The larval shells of Paphies ventricosa, reared to settlement in the hatchery, are similar in longitudinal profile to shells of some other mactracean larvae; the umbo‐stage larval shells are nearly round with the anterior margin less broadly curved than the posterior margin, the anterior end is longer than the posterior end, and the umbo is broadly rounded. Straight‐hinge larvae had total lengths up to 149 μm, and total heights up to 126 μm, and umbo larvae had total lengths up to 320 μm, and total heights up to 282 μm. The larvae settled in about 22 days at a size of about 270 μm. The larval hinge structure bears some similarities to those of other mactracean larvae.     

Comparison of the biology, dynamics, and secondary production of Talorchestia brito (Amphipoda, Talitridae) in Atlantic (Portugal) and Mediterranean (Tunisia) populations

The biology, population dynamics, and production of Talorchestia brito were studied at two sandy beaches located on the Atlantic (Portugal) and on the Mediterranean (Tunisia) coasts, respectively. The seasonal variation in abundance and the overall densities were similar in both populations. Reproduction occurred from February to September in the Atlantic, and from March to early November in the Mediterranean. The sex ratio was male biased in the Atlantic, and female biased in the Mediterranean. Based on data from the Atlantic population, both abundance and the proportion of reproductive females were positively correlated with temperature, while the proportion of juveniles in the population was positively correlated with temperature and sediment moisture. On average, individuals from the Atlantic were larger than the ones from the Mediterranean. Life span was estimated at six to nine months in the Atlantic, and five to eight months in the Mediterranean. Talorchestia brito was shown to be a semiannual species, with iteroparous females producing two broods per year, and exhibited a bivoltine life cycle. The minimum age required for males' and females' sexual differentiation and for female sexual maturation was shorter in the Mediterranean. Growth production (P) was estimated at 0.19 g m⁻² y⁻¹ ash free dry weight (AFDW; 4.3 kJ m⁻² y⁻¹) in the Atlantic population, and 0.217 g m⁻² y⁻¹ AFDW (4.9 kJ m⁻² y⁻¹) in the Mediterranean one. Elimination production (E) was estimated at 0.35 g m⁻² y⁻¹ AFDW (7.9 kJ m⁻² y⁻¹) in the Atlantic, and 0.28 g m⁻² y⁻¹ AFDW (6.3 kJ m⁻² y⁻¹) in the Mediterranean. The average annual biomass ( ) (standing stock) was estimated at 0.032 g m⁻² in the Atlantic beach, and 0.029 g m⁻² in the Mediterranean one, resulting, respectively, in ratios of 5.9 and 7.5 and ratios of 10.8 and 9.6. Like other talitrids, T. brito exhibited geographic variation in morphometrical characteristics, sex ratio, growth rates, life span, and reproduction period, with the Atlantic population presenting a slower life history.