Physiological Response of Aegiceras corniculatum Leaves to Hg~0 Stress

桐花树是我国主要的广布种红树植物,具有泌盐性。通过胁迫实验,研究桐花树幼苗叶片生理生态指标对气态单质汞(Hg0)胁迫的响应,以期了解红树植物吸收和富集气态汞的机制。结果表明:气态汞胁迫造成桐花树叶片可溶性糖含量、过氧化物酶(POD)活性下降;而丙二醛(MDA)、脯氨酸、超氧化物歧化酶(SOD)等指标上升;叶绿素含量、过氧化氢酶(CAT)活性出现先升高后降低的趋势,还原型谷胱甘肽(GSH)含量则先降低后升高。总之,虽然Hg0胁迫可增加桐花树幼苗叶的膜质过氧化程度,影响其生理代谢活动,但其叶片可通过调节抗氧化酶活性及还原型谷胱甘肽含量来提高自身抗氧化能力,进而提高对Hg0的抗性。As one of the main widespread mangrove plants in China, Aegiceras corniculatum can tolerate salt by excreting salt. Mangroves are facing more and more serious heavy metal pollution, especially the mercury contamination. To investigate the mechanism of mercury absorption and tolerance of mangrove, stress experiments were conducted with Aegiceras corniculatum seedlings under Hg0 stress. In this experiment, physiological characteristics such as the contents of chlorophyll, soluble sugars, malondialdehyde( MDA), proline( Pro), and reduced glutathione(GSH), activities of superoxide dismutase(SOD), peroxidase(POD) and catalase(CAT) of Aegiceras corniculatum seedlings' leaves were measured. Results showed as follows: the content of soluble sugars and the activity of POD gradually decreased under Hg0stress; while MDA content,Pro content and SOD activity significantly increased; the chlorophyll content and CAT activity increased firstly and then decreased, and on the contrary, the content of GSH decreased initially and then increased. The findings from above study demonstrate that although Hg0 tress can lead to damage of metabolism by causing membrane lipid peroxidation in seedlings 'leaves, but the seedlings could change activities of the antioxidative enzymes and the content of GSH to enhance the antioxidant abilities, and then strengthenorganism resistance to mercury.国家自然科学基金(No.41176090

Progress of interfacial geochemistry of mercury

国家自然科学基金资助项目(20077016);; 中国博士后基金资助项目(2002032148

Research progress on wetland ecosystem service and its valuation

通讯作者.E-mail: gzdingzhenhua@ sohu. com[中文文摘]随着对湿地重要性认识的加深,湿地生态系统的服务价值越来越受到人们的重视.湿地生态系统服务价值评价的成果可为制定惩处破坏者及补偿损失者政策提供科学依据.本文在界定湿地生态系统服务、功能和价值之间关系的基础上,总结了当前湿地生态系统服务功能价值评价的方法和应用特点,主要包括市场价格法、生产函数法、机会成本法、影子工程法、生产力变化法、人力资本法、旅行费用法、享乐价值法、权变价值评估和生态价值法.讨论了影响评价结果的因素及相关研究中存在的问题,并对今后的发展前景进行展望. [英文文摘]With the recognition on the significance of wetland, wetland ecosystem service was come under more and more attention, and its valuation could give the policymakers a scientific support in punishing wetland destroyers and compensating its losers. This paper introduced the definitions of wetland ecosystem service, its function and value, summarized their valuation approaches, including market value approach, production function method, opportunity cost approach, shadow project approach, productivity variety approach, human capital approach, travel cost approach, hedonic value approach, contingent value approach and ecological value approach, and discussed the factors affecting the valuation results of these approaches as well as the existing problems in related researches. The further research directions in these fields were also prospected.【基金】 国家自然科学基金项目(40676064,30530150);厦门大学“亚热带湿地生态学”创新团队资助项目

Enrichment of Heavy Metals by Casuarina equisetifolia of Different Stand Ages

为认识木麻黄(Casuarina equisetifolia)防护林带重金属消减效应,利用电感耦合等离子体质谱(ICP-MS)测定了福建省平潭国有防护林场林龄分别为5,15,20,30年的木麻黄小枝、细根、凋落物及林地土壤中5种重金属(Cr、Cu、Zn、Cd和Pb)的含量.结果表明:平潭木麻黄林地土壤重金属Cr、Cu、Zn、Pb、Cd含量均低于福建省土壤和福建海岸带土壤的重金属含量背景值,未发现重金属污染;木麻黄Cr、Cd和Zn的平均含量高出普通植物的正常值范围,木麻黄中重金属含量依Zn>Cr>Pb>Cu>Cd顺序降低;木麻黄细根中的重金属含量最高,且细根对重金属的富集系数也最高;木麻黄对Cr、Cu、Zn、Cd的富集系数均大于1;木麻黄细根中Zn、Cu元素含量显著正相关;小枝对Cr、Cd和Pb,细根对Zn的富集系数均与林龄极显著正相关;木麻黄现存生物量中,Cr、Cu、Zn、Cd和Pb的现存储量分别为3.06~3.46 kg/hm2,1.14~1.57kg/hm2,11.67~12.57 kg/hm2,0.05~0.09 kg/hm2和0.45~1.84 kg/hm2,且主要存在于根和树干中;随着林龄的增加,木麻黄积累大量的重金属,并达到其峰值.综上所述,木麻黄防护林在防风固沙的同时,能够吸收富集大量的重金属,对海岸带的重金属污染具有明显的消减作用.Casuarina equisetifolia is the key species in the seashore shelter belt in Fujian Province.It is necessary to assess enrichment of heavy metals by C. equisetifolia.Concentrations of heavy metals,including Cr,Cu,Zn,Cd and Pb,in branchlet,fine root,litter and soil of C.equisetifolia in 4 ages( 5,15,20,30 a) were determined.There was no heavy metal pollution in the shelter belt soil. The results showed that the content of the heavy metals in C. equisetifolia could be ranked from high to low as Zn>Cr>Pb>Cu>Cd.The heavy metal content of the fine root was significantly higher than the other parts,and the concentration coefficient of the fine root was also the highest in C. equisetifolia.There was a significant positive correlation between the content of Zn and Cu in the fine root. The concentration coefficients of Cr,Cd,Pb in branchlet,and the concentration coefficient of Zn in the fine root were significantly correlated with stand age.Existing reserves of Cr,Cu,Zn,Cd and Pb were 3. 06-3. 46 kg / hm2,1. 14-1. 57 kg/hm2,11. 67-12. 57 kg/hm2,0. 05-0. 09 kg/hm2,0. 45-1. 84 kg/hm2. Heavy metals mainly existed in the root and trunk.C. equisetifolia had the capability of accumulating heavy metals during growth,and the potential to reduce heavy metal pollution.国家自然科学基金(41176090);; 国家科技支撑计划(2009BADB2B0302

Impacts of mercury stress on Avicennia marina seedlings eco-physiology

为了解红树植物的重金属抗性机制,对白骨壤(AVICEnnIA MArInA)幼苗进行不同浓度Hg2+(1、5、10、50、100 Mg.l-1)的胁迫实验,测定并分析了Hg2+胁迫对白骨壤幼苗叶片的光合作用和抗氧化酶活性的影响。结果表明:叶片净光合速率随着胁迫时间的延长而降低,高浓度(≥50 Mg.l-1)Hg2+胁迫下叶片的净光合速率低于中低浓度胁迫,且高浓度胁迫的叶片净光合速率在48 H后快速下降;叶片净光合速率与胞间二氧化碳浓度呈极显著负相关,叶绿素含量随Hg2+浓度的增加而降低。气孔导度在不同浓度胁迫下反应不同,低浓度Hg2+对白骨壤幼苗光合的影响可能是气孔因素,中高浓度Hg2+对白骨壤幼苗光合作用的抑制主要是非气孔因素。低浓度Hg2+胁迫,白骨壤幼苗叶片SOd、POd活性升高,表现了一定的抗逆性,而高浓度表现为抑制作用,基本在100 Mg.l-1Hg2+胁迫下活性达到最低值。说明Hg2+可以抑制白骨壤叶片的光合活性,高浓度Hg2+胁迫削弱了白骨壤的活性氧清除能力,植物极易受到伤害。In order to understand the heavy metals resistance mechanism of mangrove,a stress experiment with the seedlings of mangrove species Avicennia marina from Fujian Province was conducted to study the impacts of different concentration(1,5,10,50,and 100 mg·L-1) mercury(Hg2+) on the seedlings leaf photosynthesis and antioxydase activities.With the increase of added Hg2+ concentration and exposure time,the seedlings leaf net photosynthetic rate(Pn) and chlorophyll content decreased.Under the stress of high concentration Hg2+(≥50 mg·L-1),the decrement of Pn was higher than that under the stress of low concentration Hg2+,and the Pn decreased rapidly after 48 h.There was a significantly negative correlation between Pn and extracellular carbon dioxide concentration(Ci).The chlorophyll content decreased with increasing Hg2+ concentration.The stomatal conductance(Gs) had different responses to the stress of different Hg2+ concentration.At low Hg2+ concentration,stomatal factors could limit the photosynthesis;while at high Hg2+ concentration,non-stomatal factors could be the main causes inhibiting photosynthesis.Low Hg2+ concentration promoted the activities of superoxide dismutase and peroxidase,while high Hg2+ concentration inhibited the activities of the two enzymes,being the lowest under the stress of 100 mg Hg2+·L-1.All the results implied that Hg2+ could inhibit the leaf photosynthesis of A.marina,and high concentration Hg2+ impaired the active oxygen elimination capability of A.marina,making the plants easily to be damaged.国家自然科学基金项目(40676064)资

Study on Existent Form of Mercury in Sediments of Miyun Reservoir,Beijng

在改进Tessier方法的基础上,利用冷原子吸收对北京密云水库沉积物中汞的形态进行研究,发现密云水库沉积物的总汞含量较高,沉积物中的汞主要以气态汞、有机汞和硫化物汞的形式存在,生物可以直接利用的汞较低,但一些目前不能直接利用的汞在一定条件下可以转化为可利用的汞,需要对此加以关注。On the bases of modified Tessier method,the existent forms of mercury in sediments of Miyun reservoir,Beijing were determined with cold vapor atomic absorption(CVAA).The results showed that total mercury in the sediments is high,and that gaseous mercury,organic mercury and sulfide mercury(residual mercury) are the main form of mercury.Most of them can not be used by biomass,but,what should be noted is that some unusable mercury can be transformed usable mercury under special conditions..国家自然科学基金(20077016);; 中国博士后基金(2002032148);; 厦门大学行动计划联合资助项

Microscopic interferometer for surface roughness measurement

We describe a phase-shifting microscopic Mirau interferometer for measurement of surface roughness in which feedback control is implemented for shifter asymptotic adjustment. The actual height resolution of our instrument is of similar to 0.3 nm with a measurement accuracy of 0.5 nm. Comments on interferometer design, experimental examples, and error analysis are also given. (C) 1996 Society of Photo-Optical Instrumentation Engineers

少穗竹和四季竹竹笋的营养成分分析

对福建省华安竹种园2种少穗竹属笋用竹少穗竹和四季竹竹笋的基本营养成分进行测定分析。结果表明:四季竹竹笋的含水量、灰分、脂肪含量高于少穗竹,但蛋白质含量低于少穗竹;而少穗竹竹笋氨基酸、必需及半必需氨基酸、呈味氨基酸总含量高于四季竹。厦门市科学技术局科研项目(编号:3502Z20102003和3502Z20144072

Absorption and enrichment of heavy metals by Casuarina equisetifolia of different stand ages in a coastal zone

为研究不同林龄木麻黄对重金属的吸收与富集作用,用ICP-MS测定了福建东山县国有防护林场10、16、20、30年生木麻黄小枝、细根、凋落物及林地土壤中的5种重金属(Cr、Cu、zn、Cd和Pb)含量。结果表明,木麻黄对不同重金属的吸收能力不同,从高到低为zn>Cr>Pb>Cu>Cd;木麻黄细根中Cr和Cu、Pb,fE和Cu,zn和Cd具有明显的协同作用;各林龄木麻黄对重金属均具有一定的耐性,对Cu、zn、Cd、Pb有很好的富集作用;20年生木麻黄的重金属年积累量最高;说明木麻黄对重金属的净化作用具有极大的潜力,20年生木麻黄作用最为明显。To assess the absorption and enrichment of heavy metals by Casuarina equisetifolia,the concentrations of heavy metals including Cr,Cu,Zn,Cd and Pb in branchlet,fine root,litter and soil of C.equisetifolia forests at four ages( 10,16,20,30) were determined.The results showed that the enrichment degree of the heavy metals in C.equisetifolia ranked as Zn > Cr> Pb > Cu > Cd.Correlation analysis showed that Cr and Cu,Pb,Fe and Cu,Zn and Cd had significant synergies in the fine roots of C.equisetifolia.C.equisetifolia had a higher capability of absorbing and accumulating heavy metals.Annual accumulation of heavy metals was highest in20 years old C.equisetifolia.Our results indicate that C.equisetifolia has a great potential for reducing the pollution of heavy metals,especially for the 20 years old forest.国家自然科学基金项目(41176090); 国家科技支撑项目(2009BADB2B0302)资

5种牡竹属笋用竹竹笋营养成分之比较

对福建省华安县竹种园5种牡竹属笋用竹云南甜龙竹、版纳甜龙竹、勃氏甜龙竹、马来甜龙竹和梁山慈竹竹笋营养进行成分比较。结果表明:5种笋用竹鲜竹笋含水量均接近或超过90%,口感较好;灰分含量勃氏甜龙竹竹笋的最高,达0.893%,版纳甜龙竹最低（0.340%）;蛋白质含量最高的是马来甜龙竹（1.717%）,最低的是版纳甜龙竹（1.260%）;勃氏甜龙竹（0.281%）和云南甜龙竹（0.292%）脂肪含量较低,马来甜龙竹（1.134%）和梁山慈竹（1.083%）脂肪含量较高;勃氏甜龙竹（0.655%）和云南甜龙竹（0.666%）粗纤维含量较低,而梁山慈竹、版纳甜龙竹和马来甜龙竹含量相近,达较高水平,分别达0.953%、0.894%和0.879%。5种竹笋均含有17种氨基酸,氨基酸总含量最高的是勃氏甜龙竹(227.64 mg·g-1),最低的是马来甜龙竹(120.43 mg·g-1);必需半必需氨基酸总含量最高的是勃氏甜龙竹（84.26%）,最低的是马来甜龙竹（50.67%）;呈味氨基酸总量最高的是勃氏甜龙竹,达212.79 mg·g-1,其次依次为梁山慈竹(164.71 mg·g-1)、版纳甜龙竹(156.35 mg·g-1)、云南甜龙竹(141.44 mg·g-1)和马来甜龙竹(115.83 mg·g-1)。厦门市科学技术局科研项目资助(3502Z20102003;3502Z20144072