红树林间隙水溶解态陆源有机质的光降解和生物降解行为分析     

鲍红艳  吴莹  张经 《海洋学报》2013,35(3):147-154

红树林输送的溶解态陆源有机质是海洋中陆源有机质的主要来源之一,对其光降解和生物降解过程的研究有助于进一步了解红树林生态系统输出的有机质在近岸的归宿以及对近岸水体生物地球化学过程的影响,因此于2010年4月在海南省清澜港红树林采集间隙水,并进行了光降解和生物降解培养实验。分析了光培养(光降解)和暗培养过程(生物降解)中溶解态有机碳(DOC)、细菌以及溶解态木质素等的变化。结果显示经历128 d的暗培养后,DOC由初始的2 216 μmol/L下降至718 μmol/L,表明红树林间隙水的生物可利用性约为70%左右;经历11 d的自然光照后,DOC下降至800 μmol/L。木质素在光降解过程中的移除速率(-0.132 d-1)远高于生物降解过程(-0.008 d-1)。光培养中,木质素的下降速率高于总体DOC。不同系列溶解态木质素的下降速率不同,随着培养的进行,紫丁香基酚类(S)与香草基酚类(V)的比值(S/V)呈下降趋势,而V系列的酸醛比值((Ad/Al)v)呈上升的趋势。对比光培养和暗培养过程中DOC和木质素的变化可以得出生物消耗是引起红树林间隙水DOC从水体中移除的主要因素;而光照则是陆源有机质从水体中移除的主要因素;光培养和暗培养过程中细菌变化的差异表明光照可以促进细菌对溶解态有机碳的利用。与其他地区比较发现,海南红树林间隙水的光降解速率与热带河流(刚果河)相近,高于温带密西西比河流,降解过程中各参数的变化[S/V和(Ad/Al)v]与其他区域接近。  相似文献   

Carbon isotopes and lignin phenols for tracing the floods during the past 70 years in the middle reach of the Changjiang River     

李中乔  吴莹  杨丽阳  杜金洲  邓兵  张经 《海洋学报(英文版)》2020,39(4):33-41

The Lake Tian E Zhou(TEZ,an oxbow lake)was formed during the rerouting of the Changjiang River in 1972,with strong influences from the main river channel and flood events.Herein,a sediment core was collected from the Lake TEZ for the measurements of carbon isotopes and biomarkers,including stable carbon isotopes(δ13C),radiocarbon composition(?14C),and lignin phenols,as well as lead-210 to reconstruct recent heavy flood events over the past 70 years.At the 24–26 cm interval,the sediment contained the highest OC%,TN%,and lignin phenols content,as well as significantly depleted 13C but enriched 14C,corresponding to the extreme flood event in 1998.In addition,statistics from t-test showed that lignin phenols normalized to OC(Λ8),the concentration of 3,5-dihydroxy benzoic acid(3,5-BD),and the ratio of p-hydroxy benzophenone to total hydroxyl phenols(PHB/HP)were all significantly different between the layers containing flood deposits and the layers deposited under normal non-flood conditions(p<0.05).These results indicate that the later three parameters are highly related to flood events and can be used as compelling proxies,along with sediment chronology,for hydrological changes and storm/flood events in the river basin and coastal marine environments.  相似文献   

长江口邻近陆架区表层沉积物的木质素分布和有机物来源分析   总被引：8，自引：1，他引：7  

杨丽阳  吴莹  张经  于灏  张国森  朱卓毅 《海洋学报》2008,30(5):35-42

对长江口邻近陆架区表层沉积物的有机物进行碳、氮元素、碳稳定同位素和木质素测定,以分析其物质来源,特别是陆源有机物的迁移埋藏。结果表明,碳与氮含量的比值为6.2~7.7,δ13C为-19.9×10-3~-22.4×10-3。8种木质素酚单位的总含量(相对于总有机碳)为0.15×10-2~1.56×10-2mg/mg,显著低于长江口门处的2.50×10-2mg/mg。香草基酚类的酸醛比平均值为0.90,表明该海区的陆源有机物是高度降解的;紫丁香级酚类与香草基酚类的含量之比为(0.78±0.35),肉桂基酚类与香草基酚类的含量之比为(0.13±0.08),表明这些陆源有机物源于草本和木本混合的被子植物。31.5°N以南站位木质素的降解程度比北部的高,草本植物源的贡献更大,被子植物的主导优势也更明显;长江输入的有机物以沿岸堆积为主,具有显著的离岸降低趋势。在31.5°N以北的陆架区,虽然近岸站位陆源有机物的贡献显著高于其他站位,但其他站位并没有离岸递减趋势。这种南北分布差别可能是由海流条件和水深梯度的差异引起的。计算结果显示,该海区表层沉积物中的陆源有机物占总有机物的5%~57%,且主要来自土壤有机质。  相似文献   

长江口盐沼湿地底栖微藻的分布特征及其对有机质产出的贡献     

商栩  管卫兵  张经 《海洋学报》2009,31(5):40-47

2006年6月(夏季)和12月(冬季)分别对长江口九段沙湿地潮滩底栖微藻的分布状况进行了调查,估算了湿地内各主要初级生产者的生产力并进行了比较。结果显示分布于该盐沼湿地的底栖微藻在光照条件下主要聚集于沉积物表层,形成其生物量随深度增加而迅速减少的垂直分布模式,并随滩面植被盖度从大到小的顺序呈现为:光滩、藨草区、米草区≈芦苇区的水平分布特征。九段沙湿地中单位面积上底栖微藻的生物量远高于上覆水中浮游植物的生物量,其单位面积生产力也显著高于后者,表明底栖微藻在源自单胞藻的湿地有机产出中占有主导地位。九段沙湿地中底栖微藻总生物量远低于地表维管植物,其生物量仅占潮滩初级生产者总生物量的约0.41%,所产出的有机质却达到潮滩总初级生产力约16.53%,意味着这种高营养、易摄取的有机产出有能力成为维持该湿地生态系统的重要食物来源之一。  相似文献   

脂肪酸标志水生生态系统营养关系的研究   总被引：3，自引：0，他引：3  

黄亮  吴莹  张经 《海洋科学》2009,33(3):93-96

类脂化合物是生物的三大重要能源物质之一,是机体代谢所需燃料的储存形式,其所连接的脂肪酸具有独特的生理作用,直接影响生物的代谢过程.  相似文献   

黄、东海溶解态无机砷的分布及其季节变化     

任景玲  刘素美  张经 《海洋通报(英文版)》2009,11(1):24-36

本文综合2000～2003年期间9个航次的研究结果,讨论了总溶解态无机砷（TDIAs,[TDIAs]=[As^5＋]＋[As^3＋]）和亚砷酸盐（As^3＋）在黄、东海的分布和季节性变化。调查海区覆盖了黄、东海不同水文和化学性质的区域,研究重点放在自长江口向东南琉球群岛沿伸的PN断面以讨论陆源输送的物质对中国陆架边缘海的影响。利用氢化物发生原子荧光光谱法（HG-AFS）分析砷的不同形态（TDIAs,As^3＋）。TDIAs受河流陆源输送的影响在近岸区域含量较高,并随着离岸距离的增加含量逐步下降。在东海陆架坡折带的近底层水中也存在TDIAs的高值中心,此区域具有低温、高盐、低悬浮颗粒物含量的特征,显示出入侵陆架的黑潮水是陆架区TDIAs另一个主要的源。TDIAs的季节性变化趋势受到长江冲淡水水量及黑潮入侵陆架强度的季节及年际变化共同影响。研究区域中As^3＋的分布特征与TDIAs相反,其含量、分布及季节性变化受到浮游植物活动的影响,表现出与叶绿索含量存在正相关关系。夏季东海陆架PN断面中As／P的化学计量比值约为2×10^3。黄、东海溶解态砷的含量与世界其它海区相近,表明其未受到明显人为活动的影响。  相似文献   

Distribution of heavy metals and nutrients in rainwater in coastal regions between the southern Yellow Sea and East China Sea   总被引：2，自引：0，他引：2  

刘昌岭张国森  任宏波张经 《中国海洋湖沼学报》2005,23(2):230-237

Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values,concentrations of heavy metals (Cu, Pb, Zn and Cd) and nutrients (NH4^-, NO3^-, PO43^-, SiO32^-) were performed.Results indicate that concentrations of most of the heavy metals and nutrients in rainwater show clear seasonal variation, i.e. high level in winter and low level in summer. Regionally, concentrations are higher in the southern Yellow Sea than in the East China Sea, but the annual input of heavy metals into oceans by wet deposition is similar in both stations. However, the input of nutrients by wet deposition in the East China Sea is 2-3 times higher than that in the southern Yellow Sea. In individual, Pb and PO4^3- are input to the sea mainly by dry deposition; whereas Cu, Zn, Cd and N compounds are input dominantly by wet deposition, the N/P ratios in the rainwater from two stations are much higher than those in seawater, showing a significant impact of atmospheric wet deposition on marine production and biogeochemical circulation of nutrients in these sea regions.  相似文献   

Examination of Silicate Limitation of Primary Production in Jiaozhou Bay, China Ⅱ. Critical Value and Time of Silicate Limitation and Satisfaction of the Phytoplankton Growth   总被引：1，自引：0，他引：1  

杨东方  张经  高振会  陈豫  孙培艳 《中国海洋湖沼学报》2003,(1)

ｔｈｅｐｈｙｔｏｐｌａｎｋｔｏｎａｓｓｅｍｂｌａｇｅｓｔｒｕｃｔｕｒｅ .ＴｈｅｄｉｌｕｔｉｏｎｏｆｓｉｌｉｃａｔｅｃｏｎｃｅｎｔｒａｔｉｏｎｂｙｓｅａｗａｔｅｒｅｘｃｈａｎｇｅａｆｆｅｃｔｓｔｈｅｇｒｏｗｔｈｏｆｐｈｙｔｏｐｌａｎｋｔｏｎｓｏｔｈａｔｔｈｅｐｒｉｍａｒｙｐｒｏｄｕｃｔｉｏｎｏｆｐｈｙｔｏｐｌａｎｋｔｏｎｄｅｃｌｉｎｅｓｏｕｔｓｉｄｅＪｉａｏｚｈｏｕＢａｙｅａｒｌｉｅｒｔｈａｎｉｎｓｉｄｅＪｉａｏｚｈｏｕＢａｙｂｙｏｎｅａｎｄｈａｌｆｍｏｎｔｈｓ.Ｔｈｉｓｓｔｕｄｙｓｈｏｗｅｄｔｈ…  相似文献   

Examination of Daytime Length＇s Influence on Phytoplankton Growth in Jiaozhou Bay, China     

杨东方  高振会张经  崔文林石强 《中国海洋湖沼学报》2004,22(1):70-82

This study showed how the daytime length in Jiaozhou Bay affected the water temperature, which in turn affected the phytoplankton growth when solar radiation was sufficient for phytoplankton photosynthesis. Jiaozhou Bay observation data collected from May 1991 to February 1994 were used to analyze the daytime length vs water temperature relationship. Our study showed that daytime length and the variation controlled the cycle of water temperature flunctuation. Should the cyclic variation curve of the daytime length be moved back for two months it would be superimposed with temperature change. The values of daytime length and temperature that calculated in the dynamical model of daytime length lag vs water temperature were consistent with observed values. The light radiation and daytime length in this model determined the photochemistry process and the enzymic catalysis process of phytoplankton photosynthesis. In addition, by considering the effect of the daytime length on water temperature and photosynthesis, we could comprehend the joint effect of daytime length, water temperature, and nutrients, on the spatiotemperal variation of primary production in Jiaozhou Bay.  相似文献   

北极新奥尔松(Ny-lesund)地区环境中有机碳组成来源的初步分析   总被引：1，自引：0，他引：1       下载免费PDF全文

李中乔  吴莹  张经 《极地研究》2014,26(4):425-432

对2010年8月从北极新奥尔松地区(Ny-lesund)中国黄河站附近所采集的土壤、沉积物和苔藓进行整体指标[OC%,TN%,δ13C(‰)]和木质素(lignin-derived phenols)分析;并对土壤和沉积物进行粒度分析。结果显示OC%与TN%具有相同的来源;但是粒度并不是控制有机物分布的主要因素。数据显示当地木质素主要来自当地的维管植物和苔藓,但是可能会受到当地动物或者微生物的影响。木质素的降解参数(Ad/Al)v值的大小顺序为沉积物土壤苔藓,可能是由于苔藓的表面吸附了细颗粒的煤炭,但是缺少14C数据,无法定量计算煤炭对环境中有机碳的贡献;另外一个降解参数肉桂基酚类两种单体(CAD/FAD)比值由苔藓、土壤、沉积物依次降低,反映出成岩作用增强,木质素降解程度增加。综合OC%、TN%、δ13C(‰)和木质素数据,中国北极黄河站周围环境中的有机碳来源主要为当地的苔藓和维管植物,也有可能吸附了一些煤颗粒,但是由于技术手段的限制,煤炭的贡献在当前的数据解析下无法定量评估。  相似文献