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11.
自2015年5月至2016年3月在深圳湾布设了3个站位,对该海域进行了每季至少1次共7个航次的浮游细菌生物量调查。结果表明:(1)深圳湾浮游细菌生物量季节均值的变化范围为(4.90~86.90)×10-2μg·mL-1,总均值为3.14×10-1μg·mL-1;(2)深圳湾浮游细菌生物量的季节变化模式为:冬季(5.98×10-1μg·mL-1)>秋季(3.02×10-1μg·mL-1)>夏季(2.79×10-1μg·mL-1)>春季(7.52×10-2μg·mL-1);(3)从空间分布来看,浮游细菌生物量湾中含量最高,湾口其次,湾顶最低;(4)深圳湾浮游细菌生物量与亚硝氮含量呈极显著的正相关(P<0.01),与氨氮含量呈显著正相关(P<0.05);(5)深圳湾水体中浮游细菌丰度季节均值变化范围为(2.45~43.50)×106个·mL-1,年均值达1.57×107个·mL-1;(6)从整体的细菌丰度及生物量来看,深圳湾海域呈现富营养化状态,湾中最严重,湾口次之,湾顶最轻。 相似文献
12.
为探究珊瑚共生菌对白化的响应,采用OTU分析和Biolog技术对比了鹿角杯形珊瑚（Pocillopora damicornis）健康个体与白化个体细菌群落在结构和功能上的差异。结果显示:物种组成（属水平）上两者的优势成分相似,均由聚球菌Synechococcus占主导（大于50%）;其余组分中,红球菌Pelagibacter、谱尼螺杆菌Puniceispirillum、珊瑚微球菌Coraliomargarita和光合细菌Photobacterium在健康个体中居多;而厚壁菌Actinomarina、梨形浮霉菌Blastopirellula以及一些病原菌（如弧菌Vibrio、单胞菌Pseudospirillum、Alteromonas和考克斯氏体Coxiella）在白化个体中占优。生物多样性显示白化组的α-多样性（Chao Ⅰ,Shannon index）显著低于健康组（P<0.05）。Personal分析表明温度和营养盐（硝酸盐、磷酸盐）是影响物种组成最相关的环境因子。功能分析显示:在碳源的利用上,健康组对碳源的利用从大到小的顺序为羧酸类、氨基酸类、双亲化合物、糖类、多聚物、胺类;而白化组对碳源的利用偏向糖类、氨基酸和胺类。羧酸和糖类的利用率导致了白化组与健康组对碳源摄取能力的差异。氮源的利用上两者均以无机氮为主,但白化组显示出部分消耗有机氮（肽）的能力。磷源的代谢上两者均优先利用无机磷,而白化组弱化了对有机磷的代谢能力。本次研究的结果表明白化降低了珊瑚共生菌的生物多样性,并引起了菌群对C、N、P的代谢差异,致使共生微生物呈现结构和功能上的变化。 相似文献
13.
As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs).
In the present study, the toxicity of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl)
phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos
died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch.
In embryo toxic test, embryos incubated at the highest concentration of DMP, DEP and DBP solutions showed significantly high
abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in
all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control.
Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP.
Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos
of H. diversicolor supertexta can be used to indicate toxicity of the PAEs.
Supported by National Natural Science Foundation of China (No. 40476057) 相似文献