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Tokyo Bay bottom sediments were analyzed for 2-ethyl-3-methylmaleimide, a degradation product of chlorophylls, which has been detected in ancient sediments. It was found in all sediments examined in concentrations of about 1 to 15 nmol/g- of dried sediment, and it was shown to be preserved for 100 years in the sediments. Its depth distribution agreed with that of the reported total organic carbon content of the sediments, reflecting a change in primary productivity. We concluded that this maleimide was produced under photic and oxygenic conditions in nature before the incorporation of photosynthesizing organisms into sediments.  相似文献   

3.
In situ seasonal variations in stomach contents of Aurelia aurita (L.) in Tokyo Bay, Japan, were analyzed. Copepods, such as Oithona davisae Ferrari & Orsi were the predominant food items of A. aurita from June to November. The mean digestion time measured in incubation experiments was 0.95 h. Daily rations calculated using stomach content data and digestion times were 2.2–21.8 mg C ind–1 corresponding to 0.58–5.56% of body carbon. The ingestion rate increased significantly with an increase in medusa size, although no significant relationship was found between medusa size and carbon specific daily ration. The zooplankton community in Tokyo Bay is characterized by the significant dominance of O. davisae and it is assumed that the prosperity of A. aurita is caused by the high abundance of the O. davisae population. It is suggested that a food chain comprised of microflagellates, cyclopoid copepods O. davisae, and A. aurita is the most significant one in Tokyo Bay and only a small portion of production is transferred to fish.  相似文献   

4.
在发酵生产利福霉素SV的过程中,其菌丝体的生长代谢情况及产物发酵合成都与有活力的菌丝量密切相关.介绍了在线活细胞传感仪测定活细胞量的方法,它利用细胞的介电特性,能够排除发酵液中固含物的干扰,测得的电容值与活细胞浓度呈线性相关,可以作为工艺优化过程中的关键参数.通过电容变化反映的前期生长出现的二次生长现象,进行了通过使用迟效氮源豆饼粉代替了原培养基中价格昂贵的速效氮源蛋白胨,成功消除了发酵前期由于氮源利用转换造成的生长停滞期,利用豆饼粉情况下培养前期的OUR和CER达到了14.8和15.3 mmol/L/h,明显高于利用速效氮源蛋白胨A组的8.6和11.3 mmol/L/h,保证了持续较高的比生长速率,对于促进菌体的氧消耗速率的增加和维持有着重要的作用,明显有利于利福霉素的合成与速率的维持,氮源替代组的发酵效价达到了5969±19 U/ml,与对照组(5030±17U/ml)相比显著提升发酵单位18.7%以上.  相似文献   

5.
活细胞量是与细胞生长、代谢、生产力相关的重要生理参数。在线活细胞测定仪能够利用电容的原理检测发酵液中的活细胞量。本文详细介绍了国产在线活细胞测定仪的检测原理,并说明了其在毕赤酵母发酵过程中的应用情况。结果表明,我们设计的在线活细胞测定仪能够直接、实时、在线获得发酵过程中可靠的活细胞量,且有效避免采样操作的干扰。这一技术符合过程分析技术(PAT)的要求,并可以与其他参数相结合进行分析,作为发酵过程开发、控制和优化的有利工具。  相似文献   

6.
乳山湾东流区沉积物中不同形态磷的分布特征   总被引:2,自引:0,他引:2  
王迪迪    孙耀    石晓勇  徐林梅    孟伟  姜守轩  宋健中 《生态学报》2008,28(5):2417-2417~2423
对2003年8月在乳山湾东流区采集的沉积物样品中的不同形态磷的平面和垂直分布特征进行了分析,并探讨了这些磷的形态分布与贝类养殖的关系,结果表明,不同形态磷在贝类高密度养殖区含量大于低密度养殖区.养殖区的垂直分布比较复杂,在1~20cm范围含量均出现较大波动,这与贝类养殖活动有关.Fe-P、Al-P含量出现较大波动还与污染程度有关,Or-P还与浮游植物活动有关.养殖区Ex-P、Fe-P、NAIP占TP的平均百分含量大于非养殖区,De-P、Oc-P恰好相反.Ca-P是乳山湾沉积物中含量最高的磷形态,Fe-P 和Or-P是最主要的两种生物可获得磷.TP、Or-P含量在养殖区与非养殖区之间没有显著差异,养殖区Fe-P含量高于非养殖区,3种磷的平均含量一般大于其它海区.非生物可获得磷约占TP的60%左右.  相似文献   

7.
大亚湾海域浮游动物生态特征   总被引:2,自引:0,他引:2  
方良  李纯厚  杜飞雁  贾晓平  张伟 《生态学报》2010,30(11):2981-2991
2004年3月(春季)、5月(夏季)、9月(秋季)和12月(冬季)4个航次对大亚湾海域浮游动物进行了调查。共计鉴定浮游动物128个种类,浮游幼体14个类群。浮游动物出现的种类数依次是:夏季(90种),秋季(81种),冬季(71种),春季(47种)。浮游动物的丰度以夏季最高,平均1013.38 ind.m-3;其次是秋季,平均913.30 ind.m-3;春季最低,平均162.37 ind.m-3。浮游动物生物量的季节变化:秋季(773.89 mg.m-3),夏季(472.82 mg.m-3),冬季(286.44 mg.m-3),春季(164.11 mg.m-3),生物量高低与种类组成关系密切,秋季优势类群为水母类和毛颚类等大型浮游动物,所以生物量较高。4个季节的Shannon-Wiener多样性指数H′值、物种均匀度指数J值和物种丰富度指数D值的变化趋势十分相似:春季的3项指数值均最低,冬季最高,夏、秋季节相差不大。此外,分析结果表明:毛颚类作为优势种且4个季节均有出现,是对大亚湾海域水体较20a前水温上升的响应;浮游动物近岸生物量高于湾中部;从丰度的平面分布看,大亚湾海域浮游动物栖息环境已经不同程度受到大型建设工程和人类活动的影响。  相似文献   

8.
Inorganic Carbon of Sediments in the Yangtze River Estuary and Jiaozhou Bay   总被引:3,自引:0,他引:3  
JGOFS results showed that the ocean is a major sink for the increasing atmospheric carbon dioxide resulting from human activity. However, the role of the coastal seas in the global carbon cycling is poorly understood. In the present work, the inorganic carbon (IC) in the Yangtze River Estuary and Jiaozhou Bay are studied as examples of offshore sediments. Sequential extraction was used to divide inorganic carbon in the sediments into five forms, NaCl form, NH3 H2O form, NaOH form, NH2OH HCl form and HCl form. Studied of their content and influencing factors were also showed that NaCl form < NH3 H2O form<NaOH form < NH2OH HCl form<HCl form, and that their influencing factors of pH, Eh, Es, water content, organic carbon, organic nitrogen, inorganic nitrogen, organic phosphorus and inorganic phosphorus on inorganic carbon can be divided into two groups, and that every factor has different influence on different form or on the same form in different environment. Different IC form may transform into each other in the early diagenetic process of sediment, but NaCl form, NH3 H2O form, NaOH form and NH2OH HCl form may convert to HCl form ultimately. So every IC form has different contribution to carbon cycling. This study showed that the contribution of various form of IC to the carbon cycle is in the order of NaOH form>NH2OH HCl form>NH3 H2O form>NaCl form>HCl form, and that the contribution of HCl form contributes little to carbon cycling, HCl form may be one of end-result of atmospheric CO2. So Yangtze River estuary sediment may absorb at least about 40.96×1011 g atmospheric CO2 every year, which indicated that offshore sediment play an important role in absorbing atmospheric CO2.  相似文献   

9.
Polynuclear aromatic hydrocarbons (PAH), including fluoranthene, pyrene, benzo(a)-anthracene, chrysene, benzo(a)pyrene (benzo(e)pyrene), dibenzo(a,h)anthracene and benzo(ghi)perylene, were identified and determined in sediments from Tokyo Bay. Their concentrations were proved to be in a range from several tens to several hundreds µg/kg of dry samples. This seems to suggest that the smaller are the average particle sizes of sediments and the higher are the total amounts of PAH concentrations.

Statistically significant positive correlations were observed between the following pairs: total amount of PAH vs. clay content; total amount of PAH vs. the sum of (clay + silt) contents; total amount of PAH vs. ignition loss. In addition, significant positive correlations were statistically found between ignition loss and clay content as well as the sum of (clay + silt) contents.  相似文献   

10.
胶州湾菲律宾蛤仔生物量与资源评估   总被引:8,自引:0,他引:8  
利用1998∽2003年胶州湾10个站中3个站的具有统计学意义的调查数据,对菲律宾蛤仔的生物量、生长期、年龄结构等进行了分析,从而对近期蛤仔的资源进行了初步评估。结果表明,蛤仔种群经过多年的增长延滞期之后,目前开始慢慢恢复。  相似文献   

11.
胶州湾西部海域大型底栖动物多样性的研究   总被引:1,自引:0,他引:1  
为了揭示胶州湾最近几年底栖动物多样性的变化, 作者于2003年9月到2004年9月在胶洲湾西部海域5个测站每2个月1次共进行了7个航次采样, 以种类组成、生物量和栖息密度为基础, 对大型底栖动物多样性进行了分析。使用PRIMER软件计算得到以下变量: 群落的物种数(S)、丰富度(D)、Shannon-Wiener物种多样性指数(H')和均匀度指数(J')。结果表明: 位于大沽河口的D站和水道中央的S站的多样性最低; 养殖区内外站位的多样性差异显著; 丰度/生物量曲线表明, 养殖区内的底栖动物群落已经受到了一定程度的扰动。群落物种数(S)和丰富度(D)的季节性变化明显, 春季和秋季较低, 夏季和冬季较高。分析菲律宾蛤仔(Ruditapes philippinarum)增养殖区的站位(D)发现, 多样性指数和丰富度与次级生产力有着负相关的关系。物种多样性指数和丰度/生物量曲线的分析显示, 该研究海域处于一个轻度人为扰动的状态。  相似文献   

12.
Abstract

The aim of this study was to determine the levels of heavy metals (Al, Cd, Cr, Cu, Fe, Mn and Pb) in the geochemical fractions of the coastal surface sediments from the Bacochibampo Bay in Sonora, Mexico. Two surveys were conducted (March and September) during 2004, at eight sampling stations inside the bay, and in three natural effluents discharged into this bay. The extraction of metals was carried out using a microwave oven method and the quantification was done by atomic absorption spectro-photometry. The highest detected concentration of total heavy metals in sediments was: Fe>Al>Mn>Pb>Cr>Cu>Cd, with the following concentration values: Fe (1.72%), Al (1.03%), Mn (416.31 mg kg?1), Pb (11.73 mg kg?1), Cr (11.41 mg kg–1), Cu (6.78 mg kg–1) and Cd (1.33 mg kg–1). The levels of total heavy metals (Al, Cr, Cu, Fe, Mn and Pb) were much less than the lowest observable effect level (LEL) which indicates that the sediments were not from polluted areas and that the origin of the metals was due to natural conditions. However, concentrations of Cd were much higher than the low effect level (LEL), over 40% of metal was detected in the exchangeable fraction and carbonates. The normalisation study showed a high degree of enrichment of Cd in all the sampling stations in the Bacochibampo Bay (samples EF 34–87) and in the natural flows that discharge into this bay (samples EF 22–35%), which exceeds by several orders of magnitude the value of sample EF 1, which indicates that Cd is anthropogenically induced. Based on these results, it is important that precautionary measures are established, since the deposited Cd in these fractions may be potentially toxic, due to the physicochemical changes that occur in the environment. Thus, future studies will focus on identifying problems involved with Cd bioaccumulation in different trophic levels.  相似文献   

13.
A new species of poecilostomatoid copepod, Hemicyclops tanakai n. sp. was collected from burrows of the mud shrimp Upogebia major in an estuarine mud-flat in Tokyo Bay. The new species can be distinguished from its congeners by combination of the following characteristics: setation of the antennule, the segmentation of the antennule, the length–width ratio of the caudal ramus, the ornamentation on the third segment of antenna and the shape of the genital double somite.  相似文献   

14.
通过野外调查黄土丘陵区不同发育年限退耕地上藓结皮发育状况,结合室内测定,提出了藓类植物生物量测定的回归方程法.运用该方法测定了研究区9个不同发育年限藓类植物的生物量,并分析了其随发育年限的变化趋势.结果表明,研究区藓类植物个体微小,株高相同的藓类植物生物量变异很小,不同株高的藓类植物的株数与其生物量之间呈显著的线性相关关系(R2>0.96,n=7).因此,可以利用藓类植物株数与生物量之间的统计回归关系式估测生物结皮中藓类植物的生物量.用所建立的回归方程估测的研究区不同年限退耕地藓类植物生物量的绝对误差为1.3%~27.3%.研究区藓类植物生物量随结皮发育年限而变化,在退耕的前11年里,藓类植物生物量随发育年限的延长而增加,至11年时藓类植物生物量达到最大值(303.8g/m2),此后藓类植物生物量变化不大甚至还有下降趋势.  相似文献   

15.
The origin of organic matter in recent anoxic sediments of the alpine Lake Bled (NW Slovenia) was determined by analyzing the carbon isotope composition of lipid biomarkers, i.e. alkanes, alcohols, sterols and fatty acids, busing compound specific, carbon isotope analysis. The results indicate that, although biomarker analysis indicated mostly plankton and terrestrial sources for lipids, an important part of sedimentary lipids, especially sterols, are autochthonous, of anaerobic microbial (methanotrophic) origin. Marked differences were observed in δ13C values of lipid biomarkers in settling particles collected 2 m above the bottom, and in δ13C values determined in surface sediment. These results indicate that even some compounds found in both particulate organic matter and sediments are the same in terms of chemical structures, their sources can be different and thus, isotopic composition should be used as a complementary tool for source identification.  相似文献   

16.
沉积物记录揭示的深圳湾红树林生态系统稳态转变   总被引:1,自引:0,他引:1  
稳态转换作为滨海生态系统的一种灾变现象,其过程伴随着生态系统质量下降和功能退化。深圳湾位于粤港澳大湾区的核心区域,深入理解其生态系统演化过程是进行适应性管理的重要前提。2014年于深圳湾福田红树林湿地获得4根岩芯沉积柱,通过分析沉积和生物地球化学指标(包括金属元素、营养盐、粒度和有机质指标),重建半个世纪以来深圳湾环境的历史变迁,揭示其生态系统发生的稳态转变过程。结果表明:稳态转换发生前(1954-1980),福田红树林沉积物中重金属、无机营养和有机物含量稳定增加,但处于较低水平;稳态转换发生后(1990-2014),深圳湾中污染输入增加,沉积物中重金属和营养盐含量发生明显变化,深圳湾生态系统质量持续下降。通过揭示深圳湾生态系统演变过程及其稳态转变的发生规律,为粤港澳大湾区生态系统修复和管理提供重要的理论依据和参考。  相似文献   

17.
土壤微生物量测定方法概述   总被引:22,自引:0,他引:22  
土壤微生物量是土壤生态系统研究的重要参数之一。常用的土壤微生物量的测定方法主要包括:直接镜检法、熏蒸系列方法、底物诱导系列方法、成分分析法和比色法。对这些具体测定方法、原理及其优缺点进行了简要的评述,并指出了应用这些方法须注意的问题和今后的研究方向。  相似文献   

18.
We identified 16S rRNA gene sequences in sediment samples from Ago Bay in Japan, forming a new branch of the anammox group or closely related to anaerobic ammonium oxidizing (anammox) bacterial sequences. Anammox activity in the sediment samples was detected by 15N tracer assays. These results, along with the results of fluorescence in situ hybridization (FISH) analysis, suggest the presence of anammox bacteria in the marine sediments.  相似文献   

19.
分别于2004年10月(秋季)和2005年1月(冬季)对三亚湾进行了现场综合调查,研究了海区浮游植物和细菌生物量的分布特征,探讨了它们与DIN、PO34-、DO、BOD5等环境因子的关系。结果表明,海区平均叶绿素a浓度秋、冬季分别为:(1·40±0·78)mg/m3和(2·25±3·62)mg/m3;浮游植物生物量秋季为:(70·36±38·91)mgC/m3,冬季为:(112·57±181·38)mgC/m3。海区细菌的丰度秋、冬季分别为:(9·87±5·90)×108cells/L和(6·58±2·43)×108cells/L;平均细菌生物量秋季为:(19·73±11·81)mgC/m3,冬季为:(13·15±4·86)mgC/m3。表、底层浮游植物和细菌的生物量分布均呈现三亚河口最高,离岸逐渐降低的态势,三亚河的陆源物质输送及其入海扩散是引起此分布特征的主要原因。温度是造成秋季细菌的生物量高于冬季的原因之一。溶解无机氮为控制表层浮游植物和细菌分布的重要因子。秋季除表层DIN外各环境因子与浮游植物和细菌生物量都不存在明显的相关性;冬季表层DIN、PO43-、DO和BOD5均在p<0·01水平下与二者呈非常显著相关,底层仅DIN和BOD5在p<0·01水平下与二者呈非常显著正相关。三亚湾浮游细菌和浮游植物生物量间的相关性明显,初级生产是水域浮游细菌分布的重要影响因素。  相似文献   

20.
青岛湾小型底栖生物周年数量分布与沉积环境   总被引:1,自引:0,他引:1  
2006年6月至2007年5月对青岛湾潮间带泥沙质和沙质沉积物中的小型底栖生物及环境因子进行了周年逐月采样。研究发现, 小型底栖生物在两个底质中的数量和分布上差异极大, 泥沙质中的年平均丰度高达(4853±1292) 个/10 cm2, 沙质中为(1528±569) 个/10 cm2, 生物量则分别为(3186.9±1993.4) μg干重/10 cm2和(1601.5±786.2) μg干重/10 cm2。在季节相上, 小型底栖生物丰度在沙质底呈双峰模式 (高值出现在6、12月份, 低值出现在3、9月份); 泥沙质中最高值出现在6月份, 最低值出现在11月份。在0-8 cm 深沉积物中, 48%的小型底栖生物集中于0-0.5 cm 表层, 分布在0-4 cm的逾86%。共发现13个主要类群, 线虫在丰度上占绝对优势(泥沙质中为95%, 沙质中为66%), 其它较优势类群在泥沙质依次为多毛类 (2%)、甲壳类幼体 (2%) 和桡足类 (1%); 沙质底则依次为甲壳类幼体 (13%)、腹毛类 (8%) 和桡足类 (6%)。泥沙质中线虫在生物量上的贡献达58%, 而在沙质中其所占生物量 (25%) 低于腹毛类 (28%)。聚类分析表明, 泥沙质和沙质沉积环境间的相似度为87%, 生物丰度组成间的相似度为71%; BIOENV分析表明, 温度、盐度、粒度及粘土粉砂含量的组合最能解释月份和站位间的差异 (r=0.614)。结合历史资料的对比研究表明, 青岛湾近海的沙质环境状况已有明显改观, 但泥沙质的污染状况仍然堪忧, 这由小型底栖生物的高丰度值、相较耐污的线虫所占的极高比例以及线虫与桡足类丰度的高比值即可看出。  相似文献   

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