【作者】 刘保占；

【导师】 刘瑀；

【作者基本信息】 大连海事大学 ， 环境科学， 2013， 博士

【摘要】 本论文以稳定同位素分析技术为基础,对我国北方海域食物网结构进行了研究。确立了一套海洋食物网样品碳、氮稳定同位素分析的保存和预处理方法。通过不同氮磷比对北方海域典型赤潮藻碳、氮稳定同位素组成影响的研究,为北方海域食物网研究提供了基础数据。通过沉积物和悬浮颗粒有机物碳、氮稳定同位素组成变化,判断有机质来源,探讨陆源输入对海洋环境造成的影响。了解了北方海域食物网结构及营养关系,不同类型生物之间的食性差异等,为揭示北方海域食物网的物质循环和能量流动提供基础数据。依据上述方法,对海洋食物网样品碳、氮稳定同位素分析的保存和预处理方法研究。干燥保存是样品长期保存的最佳方法。冷冻干燥是常用的去除生物样品中水分的方法；〥N分析样品不需要进行酸化处理,〥C分析样品SOM、POM、浮游动植物及甲壳动物需酸化处理；样品酸化前水洗,酸化后不需要水洗。不同赤潮藻〥C和〥N值存在一定差异。赤潮藻〥C值与NO3和P04浓度普遍呈显著正相关；〥N值与N03浓度普遍呈显著负相关,与P04浓度普遍呈显著正相关。悬浮颗粒有机物〥C和〥N值总体趋势是由陆向海增大,季节变化不明显(分别为P=-0.84和P=0.55)。表层沉积物稳定同位素组成总体变化趋势与悬浮物相同,沉积物各站位〥C和〥N值存在极显著性差异(p<0.01)。不同季节潮间带沉积物中〥C值不存在显著性差异(p=0.31),〥N值差异显著(p<0.05)。底栖动物不同种类样品碳、氮稳定同位素组成随季节变化而不同。底栖食物网生物营养级位于2.07~3.92之间,与北黄海海域相比,辽东湾海域潮间带10种底栖动物〥C和〥N值有所增加(除斑管栖纽虫〥N值)。游泳动物(55种)〥C和〥N值范围分别为-20.90~13.96%o和8.69-14.25%o,营养级范围为3.02-4.59。除日本嚼和许氏平触,两个海域13种游泳动物〥C和〥N值无显著性差异。〤C和〥N值都与体长存在显著性对数相关。营养级与体重等级之间存在显著性相关,〥C平均值与体重(1og2)无显著性相关,〥N平均值与体重(1og2)存在显著性相关。捕食者-食物体重比为904.26：1。更多还原

【Abstract】 Based on the analysis of stable isotopes, the food web structures of Northern China Seawere studied. The comprehensive sample preservation and processing methods of marine food web for stable isotopic analysis were given. Basic data of Northern Sea were provided by the study of stable carbon and nitrogen isotope values of the typical algae. In order to provide crucial information on the major sources of organic matter, spatial and temporal variations of carbon and nitrogen stable isotopes in intertidal suspended particulate organic matters and sedimentswere evaluated. According to the variations of813C and815N of intertidal and main nektonic food web in Northern Sea, the food web structre and trophic relationships, and feeding habits among different biolo-gical were explored.The main results are as follows:We suggest that drying is the most suitable method for preserving samples, since it does not affect the the stable isotope values of the samples. Freezedrying is a common method used for the removal of water from biologic samples; Samples should not be acidified for nitrogen isotope analysis. Moreover, acidification is needed for carbon stable isotope analysis in samples of SOM, POM, plankton and crustaceans. Samples should be washing before acidification, while should not be after acidification.The results of813C and δ15N values of the typical algae in Northern Sea showed that the carbon and nitrogen isotopic signatures of phytoplankton were differ among di-fferent phytoplankton species. There were significant positive correlation between813C values and concentration of NO3-and PO43-. There were significant negative correlation between815N values and concentration of NO3-, while significant negative correlation between815N values and concentration of PO43-.General trend of813Cand δ15N valuesin POMwas increasing from land to sea. Seasonal variation of813C and815N values were not significant (p=0.84and p=0.55, respectively). The isotopic values of SOM and POM had the same trend. There were significant differences813C and815N values in sediment in each station (p<0.01). The813C values of sediment in different seasons had not significant differences (p=0.31), while815N values were significant differences (p<0.05). The δ13C and δ15N values of benthos were different with season. The trophic level in benthic food web was from2.07to3.92. The δ13C and815N values ofzoobenthos in Liaodong Gulf were higher than northern Yellow Sea (except815N in Tubulanus punctatus). Studies on the stable isotope ratios of the main nekton (55species) indicated that813C rangingfrom-20.90‰to-13.96‰, and δ15N from8.69‰to14.25‰. The trophic level was from3.02to4.59. The813C and δ15N values between Liaodong Gulf and northern Yellow Sea were not significant differences except Charybdis japonica and Sebastes schlegeli. The813C and815N of nektonvalues were logarithmic correlation to the body length. Trophic level was closely related to the body weight. The average815N values were significant correlation to the body size (log2). The ratio of predator and food resources in the study area was904.26.更多还原