Distribution of Mercury in Surficial Sediments from Main Mangrove Wetlans of China

作者简介: 丁振华(1966~ ) , 男, 博士, 教授, 主要研究方向为污染生 态学, E-mail : dzh@ xmu. edu. cn[中文文摘]通过对我国主要红树林区表层沉积物中总汞含量和环境因素的测定,研究了红树林湿地沉积物中汞的分布规律和影响因子之间的关系.结果表明,我国红树林湿地沉积物中总汞的含量范围是2.3~903.6 ng.g-1,平均值为(197±137.6)ng.g-1,福建洛阳桥[(467.5±68.8)ng.g-1]、浮宫[(438.2±147.0)ng.g-1]、鹅湾[(264.3±89.2)ng.g-1]、姚家屿[(125.4±27.1)ng.g-1],海南三亚[(164.8±143.9)ng.g-1]、东寨港[(314.1±335.7)ng.g-1],广东深圳[(179.9±7.7)ng.g-1]等7个红树林区的汞含量均显著高于当地土壤背景值,汞污染严重;而福建云霄[(63.3±43.9)ng.g-1]、广东高桥[(178.6±127.0)ng.g-1]、广西大冠沙[(26.1±18.8)ng.g-1]、山口[(73.8±21.1)ng.g-1]、北仑河口[(117.8±51.4)ng.g-1]、钦州湾[(147.5±107.6)ng.g-1]等红树林区汞含量接近于背景值,基本无污染.红树林湿地中汞含量的差异是众多环境因素和人类活动相互交叉影响的结果.红树林湿地中,pH值、粒度、有机质、Fe/Hg、Mn/Hg与总汞含量显著相关.其中,黏粒和Fe/Hg是影响沉积物中汞含量最显著的因素.环境因素对总汞含量的综合影响作用,可以用线性回归方程表示.[英文文摘]Surficial sediment samples were collected from main mangrove wetlands of China, mercury, pH, salinity, organic matters, grain size, Fe/Hg , Mn/Hg were analyzed. Mercury content ranges from 2.3 to 903.6 ng.g- 1, with a average of ( 197±137.6) ng.g- 1. Compared with local background level, serious Hg pollution with high Hg content was found in 7 areas, including Luoyangqiao [ ( 467.5 ±68.8)ng.g- 1] , Fugong [ ( 438.2 ± 147. 0) ng.g- 1 ] , Ewan [ ( 264.3 ± 89.2) ng.g- 1 ] , Yaojiayu [ ( 125.4 ± 27.1) ng.g- 1 ] , Fujian Province;Sanya [ ( 164. 8 ±143.9) ng.g- 1 ] , Dongzhaigang [ ( 314.1 ±335. 7) ng.g- 1 ] , Hainan Province, Shenzhen [ ( 179.9 ±7. 7) ng.g- 1 ] ,Guangdong Province. Hg content was similar with background value in the other 6 areas, including Yunxiao [ ( 63.3 ±43.9) ng.g- 1 ] , Fujian Province; Gaoqiao [ ( 178. 6 ± 127.0) ng.g- 1 ] , Guangdong Province; Daguansha [ ( 26.1 ±18.8) ng.g- 1 ] , Shankou [ ( 73.8±21.1)ng.g- 1 ] , Beilun estuary [ ( 117.8 ±51. 4) ng.g- 1 ] , Qinzhou Bay [ ( 147.5 ±107. 6) ng.g- 1] , Guangxi Autonomous Region. Discrepancy of total Hg concentrations in mangrove wetlands is due to many environmental factors and human activities. Parameters such as grain size, pH,organic matter, Fe/Hg, Mn/Hg are significantly correlated with total Hg respectively. Clay and Fe/Hg are obvious factors influencing total Hg concentration. Impact of environmental factors on mercury can be showed by regression equation.国家自然科学基金项目(40676064,30530150);厦门大学创新团队项

Distribution of Hg in Mangrove Plants and Correlation with Hg Speciation in Sediments

为了解红树植物对汞的富集能力和影响因素,对我国几种主要的红树植物的汞含量、沉积物总汞含量和形态进行了研究.结果表明,几种主要红树植物的总汞含量范围为817.5~3 197.6 ng/g,具有明显的种间差异和器官差异.秋茄汞含量为(1 579.4±1 326.8)ng/g,桐花树为(2 115.1±1 892.3)ng/g,白骨壤为(2 159.3±1 678.7)ng/g,木榄为(2 566.5±821.6)ng/g,海漆为(2 104.3±1 661.8)ng/g,无瓣海桑为(3 197.6±2 782.8)ng/g,老鼠簕为817.5±632.3 ng/g,红海榄为(1 801.8±1 255.4)ng/g.各种红树植物对汞的吸收能力的顺序为:无瓣海桑>木榄>白骨壤>桐花树>海漆>红海榄>秋茄>老鼠簕.我国主要红树林地区表层沉积物的汞形态主要为易挥发态,其次为硫化物及有机结合态或可交换离子态,少量为碳酸盐结合态和铁锰氧化物结合态,残渣态少量甚至没有.只有深圳红树林沉积物中的汞以残渣态为主,其次为硫化物及有机物结合态.无瓣海桑的茎和叶,海漆叶的汞含量与易挥发态汞、可交换态汞具有显著正相关关系,而大多数红树植物的茎汞和叶汞含量与沉积物的总汞含量、不同形态汞之间并没有明显的相关性.红树植物富集的汞来源多样,且这些不同来源的汞在植物体内可能是能够迁移的.Plant is an important role in biogeochemical cycle of Hg.The aim of this study is to ascertain Hg accumulation in several kinds of mangrove plants,and to discuss relationship among Hg concentrations in mangrove plants and different Hg speciation in sediments.Contents of total mercury(THg) in mangrove plants and sediments were determined.Hg speciation was determined with a modified Tessier's method.Contents of THg of the mangrove plants were in the range of 817.5-3 197.6 ng /g.In detail,Hg concentration was(1 579.4 ± 1 326.8) ng /g in Kandelia candel,(2 115.1 ± 1 892.3) ng /g in Aegiceras corniculatum,(2 159.3 ± 1 678.7) ng /g in Avicennia marina,(2 566.5 ± 821.6) ng /g in Bruguiera gymnorrhiza,(2 104.3 ± 1 661.8) ng /g in Excoecaria agallocha,(3 197.6 ± 2 782.8) ng /g in Sonneratia apetala,(817.5 ± 632.3) ng /g in Acanthus ilicifolius,(1 801.8 ± 1 255.4) ng /g in Rhizophora.stylosa,respectively.There are obvious interspecific variation,and organic variation in THg contents of mangrove plants,which is closely related to environment and physiological characteristics of mangrove plants.Enrichment of THg in mangrove plants was inhomogeneous,following the order of Sonneratia apetala > Bruguiera gymnorrhiza > Avicennia marina > Aegiceras corniculatum > Excoecaria agallocha > Rhizophora stylosa > Kandelia candel > Acanthus ilicifolius.Mercury exists mainly in volatile form in most mangrove wetlands,but mainly in the form of residue in sediments from Shenzhen mangrove wetlands.Significantly positive correlations were found among Hg concentrations in leaves and stems of Sonneratia apetala and volatile Hg,exchangeable Hg of sediments.Significantly positive correlations were also found among Hg concentrations in leaves of Excoecaria agallocha and volatile Hg,exchangeable Hg of sediments.But,there is no significant correlation between Hg concentrations of most mangrove plants and different Hg speciation in sediments.It showed that plants assimilate Hg from different sources,such as water,sediment and air,and that Hg assimilated by plants could transfer among different plant organics.国家自然科学基金项目(40676064;30530150

面向城市可持续发展的自然解决途径(NBSs)研究进展

自然解决途径(NBSs)是近几年生态学应用研究的热点,其理念是综合考虑经济、环境和社会效益,引入自然生态系统服务功能用来修复、恢复甚至提升城市生态基础设施水平,进而解决城市面临的可持续发展挑战。自然解决途径的提出为生态设计注入了新鲜的血液,提供了新的视野和技术方法。基于VOSviewer文献计量分析软件对城市自然解决途径研究的热点关键词、主要研究国家、机构以及全球分布进行了综合分析。结果发现:(1)2015年至2018年有关城市NBSs的研究论文逐渐增多,覆盖6大洲(欧洲、北美洲、亚洲、南美洲、大洋洲、非洲),多数案例是对已有实施工程中采用的可以归纳为自然解决途径的某些方法或者经验的总结凝练;(2)与城市NBSs相关研究热点从高到低主要涉及生态系统服务、绿色基础设施、气候变化、人群健康与福祉;(3)城市自然解决途径研究的主要力量主要聚集在欧洲,目前中国对于NBSs研究仍处于初期起步阶段。将有助于促进自然解决途径研究及实践在中国的发展,同时为城市生态设计和可持续发展提供新视野和新技术。国家自然科学基金项目(41771573)国家重点研发计划(2016YFC0502702

Speciation,bioaccumulation and transportation of mercury in sediments of mangrove wetlands of China

为了认识红树林表层沉积物中Hg的生物地球化学行为,采用改进的TESSIEr连续浸取法,对我国主要红树林沉积物中Hg的形态特征进行了研究,并讨论了Hg的生物可利用性和迁移性。结果表明:(1)我国红树林沉积物中的Hg绝大部分以易挥发态为主,具有较高的生物可利用性,易挥发态Hg向大气Hg的转化是红树林湿地中汞迁移的主要方式。只有深圳红树林沉积物中的Hg以残渣态为主,次为可交换离子态和碳酸盐结合态,沉积物中Hg主要通过不可溶的固体颗粒物形式迁移,其生物可利用性较低。(2)总Hg与易挥发态Hg呈极显著正相关(r=0.967,P<0.01),碳酸盐结合态Hg与铁锰氧化物结合态Hg之间存在极显著正相关(r=0.871,P<0.01),有机结合态Hg分别与碳酸盐结合态Hg、铁锰氧化物结合态Hg存在极显著相关(r1=0.618,P1<0.01;r2=0.686,P2<0.01);有机质与总Hg存在显著正相关(r=0.526,P<0.05)。In order to understanding biogeochemical behavior,speciation of mercury in the mangrove sediments from 9 main mangrove wetlands of China were determined with modified Tiesser's method.It shown:(1) Two situations were found.One is that mercury exists mainly in volatile form in most mangrove wetlands.That volatile mercury turns into atmospheric mercury is the main transport form for most mangrove wetlands.The mangrove wetlands are the source of global mercury pollution.The mercury in sediments of mangrove wetlands can be bio-accumulated easily.Another situation is that mercury exists mainly in the form of residue which is hard to bio-accumulate,typically in Shenzhen mangrove wetlands.The mercury transports in the form of insoluble particle.(2) Significant positive correlation was found between volatile Hg and total Hg(r=0.967,p<0.01).Carbonate-bound Hg is strongly correlated with Fe-Mn oxide-bound Hg(r=0.871,p<0.01),and organic matter is significantly correlated with total Hg(r=0.526,p<0.05).Organic-bound Hg is significant correlated with carbonates-bound Hg and Fe-Mn oxide bound mercury(r1=0.618,p1<0.01;r2=0.686,p2<0.01).国家自然科学基金项目(40676064;30530150);东华理工大学核资源与环境教育部重点实验室开放基金(070717

中国海及邻近区域碳库与通量综合分析

中国海总面积约470万平方公里,纵跨热带、亚热带、温带、北温带等多个气候带.其中,南海北依\"世界第三极\"青藏高原、南邻\"全球气候引擎\"西太平洋暖池,东海拥有全球最宽的陆架之一,跨陆架物质运输显著,黄海是冷暖流交汇区域,渤海则是受人类活动高度影响的内湾浅海.中国海内有长江、黄河、珠江等大河输入,外邻全球两大西边界流之一的黑潮.这些鲜明的特色赋予了中国海碳储库和通量研究的典型代表意义.文章从不同海区（渤海、黄海、东海、南海）、不同界面（陆-海、海-气、水柱-沉积物、边缘海-大洋等）,以及不同生态系统（红树林、盐沼湿地、海草床、海藻养殖、珊瑚礁、水柱生态系统等）多层面对海洋碳库与通量进行了较系统地综合分析,初步估算了各个碳库的储量与不同碳库间的通量.就海气通量而言,渤海向大气中释放CO2约0.22Tg Ca-1,黄海吸收CO2约1.15Tg Ca-1,东海吸收CO2约6.92～23.30Tg Ca-1,南海释放CO2约13.86～33.60Tg Ca-1.如果仅考虑海-气界面的CO2交换,中国海总体上是大气CO2的\"源\",净释放量约6.01～9.33Tg Ca-1.这主要是由于河流输入以及邻近大洋输入所致.河流输入渤黄海、东海、南海的溶解无机碳（DIC）分别为5.04、14.60和40.14Tg Ca-1,而邻近大洋输入DIC更是高达144.81Tg Ca-1,远超中国海向大气释放的碳量.渤海、黄海、东海、南海的沉积有机碳通量分别为2.00、3.60、7.40、7.49Tg Ca-1.东海和南海向邻近大洋输送有机碳通量分别为15.25～36.70和43.39Tg Ca-1.就生态系统而言,中国沿海红树林、盐沼湿地、海草床有机碳埋藏通量为0.36Tg Ca-1,海草床溶解有机碳（DOC）输出通量为0.59Tg Ca-1;中国近海海藻养殖移出碳通量0.68Tg Ca-1,沉积和DOC释放通量分别为0.14和0.82Tg Ca-1.总计,中国海有机碳年输出通量为81.72～103.17Tg Ca-1.中国海的有机碳输出以DOC形式为主,东海向邻近大洋输出的DOC通量约15.00～35.00Tg Ca-1,南海输出约31.39Tg Ca-1.综上,尽管从海-气通量看中国海是大气CO2的\"源\",但考虑了河流、大洋输入、沉积输出以及微型生物碳泵（DOC转化输出）作用后,中国海是重要的储碳区.需要指出的是,文章数据是基于中国海各海区碳循环研究报道,鉴于不同研究方法上的差异,所得数据难免有一定的误差范围,亟待将来统一方法标准下的更多深入研究和分析.国家重点研发计划项目(编号:2016YFA0601400);;国家自然科学基金项目(批准号:91751207、91428308、41722603、41606153、41422603);;中央高校基础研究项目(编号:20720170107);;中海油项目(编号:CNOOC-KJ125FZDXM00TJ001-2014、CNOOCKJ125FZDXM00ZJ001-2014)资

Advances of research of Cyanobacterium genome

本文对近年来蓝藻基因组研究进展进行了综述.介绍了聚胞藻PCC6803基因组研究方法和成果,包括最佳分析软件的选择,所获得的基因组基本信息,以及后基因组研究的部分成果.蓝藻基因组间差异很大,文中介绍了其它蓝藻基因组的基本信息和在各个藻种里的重要发现.文章最后探讨了蓝藻基因组的研究意义和前景.The recent research advances of Cyanobacteria genome were reviewed in this paper. As the representative of genome of Cyanobacteria, the research　methods and results of genome of Synechocystis sp.strain PCC6803 wereintroduced, including the selection about most suitable analyzing soft, the genome message and some results of its post-genome research. For the much difference among cyanobacteria, the basic message and significant discovery of others Cyanobacteriagenome were described. Furthermore, the research meaning and future develoment of the Cyanobacteria genome were discussed

一种用于测试光学探测器的地球模拟装置

本发明涉及一种用于测试光学探测器的地球模拟装置。该装置的特征在于在一个地球模型壳体中放置光源模拟地球，地球模型壳体始终有半个球可透光，并通过多维运动组合平台联接驱动，从而实现模拟在不同地球轨道上观测地球的功能；利用本发明可以广泛应用于模拟各种用以在卫星和航天器上的光学探测器观测地球以验证光学探测器性能的工作中

用黑曲霉发酵纤维素酶解液生产柠檬酸的研究

以麦草纤维素酶解液为原料 ,用黑曲霉发酵制备柠檬酸 ,研究了培养基组成、恒温发酵和周期变温发酵对柠檬酸发酵的影响 ,结果表明 ,适宜的培养基组成为NH4 NO3 0 .3% ,KH2 PO4 0 .1% ,Mg2 + 30 0&times; 10 -6,Fe2 + 10&times;10 -6,此时 ,柠檬酸产量为 10 .5 2 g/L ,糖转化率为 6 0 .80 %。研究还表明 ,添加低级醇如甲醇和乙醇有利于产酸 ,但添加甲醇的效果要好于添加乙醇的效果 ,适宜的甲醇量为 2 %。在恒温发酵过程中 ,0～ 8h为孢子萌发期 ,产酸较慢 ;8～ 2 4h为对数生长期 ,产酸增加 ;2 4h之后为菌体生长恒定期 ,但产酸继续增加 ;10 4h之后产酸降低。在周期变温发酵过程中 ,0～ 8h产酸较慢 ,8h之后产酸增加。通过对二者的比较可知 ,在 0～ 16h ,周期变温发酵的产酸量要高于恒温发酵的产酸量 ,但在 16h之后 ,周期变温发酵的产酸量要低于恒温发酵的产酸