The main biogenic element、trace metal and organic acid exudation in the root-soil interface of Kandelia obovata(S.L) under Phosphorus & Cadmium treatment

红树林生态系，广泛分布于热带亚热带的海岸潮间带，其独特的生物学和生态学特性为污染物的吸附治理提供了最佳的场所。然而，随着城市化和工业化的高度发展，大量生活污水和工业废水通过排污管道流向红树林湿地，近乎超出红树林系统的自净化能力，从而使得滨海湿地面临着日益严峻的金属污染和有机物污染。进入红树林湿地的污染物最先在根际区进行一系列的形态转化等过程而后才被植物吸收累积，因此，根际区物质循环已经成为近年来污染生态学的研究热点。对于红树林湿地而言，Cd作为一种常见的有毒金属污染物，尤为引起关注。Cd为植物非必需元素，然而其极易被红树植物吸收并累积，从而影响到红树植物生长和代谢；研究表明，Cd很大程度上影响...Mangrove ecosystem, distributed in the tropical and subtropical coastal line, is deemed as the best site for pollution removal. However, with the rapid development of urbanization and industry, large amount of waste water from daily life and industry has been dumped to the wetlands, almost exceeding the self-purification capacity of mangrove ecosystem. Coastal wetlands are facing increasing pollut...学位：理学博士院系专业：生命科学学院_生态学学号：2162010015387

Rhizosphere Remediation of Phenanthrene-contaminated Sediment by Kandelia candel(L.) Druce

利用盆栽试验方法,研究了红树植物秋茄(kAndElIA CAndE(ll.) druCE)对多环芳烃菲污染沉积物的修复作用。结果表明,在5、10、20、40Mg·kg-1菲处理浓度下,菲对秋茄的生长具有抑制作用,沉积物中菲初始浓度越高抑制作用越明显。4个月的修复试验结果表明,与无植物对照相比,种植秋茄能够明显促进沉积物中菲的降解。根际沉积物中菲的去除率为69%--82%,而非根际沉积物中菲的去除率为59%--66.9%。相同污染水平处理下根际沉积物中菲残留浓度低于非根际沉积物,而菲降解菌数量、多酚氧化酶和脱氢酶活性高于非根际沉积物,从而提高了沉积物中菲的降解率。Rhizosphere-remediation of phenanthrene(PHE)-contaminated sediment with Kandelia candel(L.) Druce was investigated in soil-culture medium.The results showed that the growth of Kandelia candel was inhibited by PHE in a dose-dependent way at 5, 10, 20 or 40 mg·kg-1 of the studied PHE concentrations.On the other hand, Kandelia candel significantly promoted the degradation of PHE in sediment.After 4 months, 69%--82% and 59%--66.9% of the spiked PHE disappeared from the rhizospheric and the non-rhizospheric sediments, respectively.The residual concentration of PHE in the rhizosphere was lower than that in the non-rhizosphere at the same treatment concentration.Planting Kandelia candel enhanced the number of PHE-degrading bacteria and the activities of polyphenol oxidase and dehydrogenase, thus it improved the degradation rate of PHE.Taken together, our results suggested that planting Kandelia candel could strengthen the remediation of PHE-contaminated sediment.国家自然科学基金项目(30710206

Study on Qianling Lake Restoration with Artificial Wetland

黔灵湖水质变坏的根源可以追溯到黔灵湖的上游小关湖,影响水质的根源是养猪废水,其中,主要污染物质为氮、磷、无机质、有机质和微生物等。在小关水库的下游建造人工湿地,种植的植物首先应选择一些去污力强,又宜于本土生长,根系发达,茎叶繁茂,具有耐污能力和抗寒能力、抗病虫能力强的植物,同时还应具有一定的观赏性。用人工湿地技术可以除去上游养猪废水和生活污水中的氮、磷、无机物质和有机物质等,将废水中的氮和磷转化为生物体组织中的氮和磷,从而减少了微生物的大量繁殖形成的“水华“导致黔灵湖水质变坏。同时,通过生物循环可获得一系列的生物产品(小关湖种植凤眼莲、浮萍等浮游植物可以为养猪提供饲料;在小关水库养殖的鱼、虾和贝等和在小关湖下游的湿地种植藕、菱、芡和茨菰等是富有营养的副食品;有些湿地动植物还可入药或作为发展轻工业的重要原材料),还可以美化黔灵公园,从而具有重要的教育意义和实用价值。The ecological restoration of water quality in Qianling Lake was conducted by artificial wetland,which transformed N and P in wastewater into essential matters in organism tissues,so pollutants discharged into Qianling Lake were reduced for the purpose of restoration.SupportedbyNationalNaturalScienceFoundation(30530150;40673064;30710103908);InnovationTeamProjectinUniversitiesofFujianProvince---

Responses of Phenolic Compounds in Kandelia obovata(S.L.)Yong to Cadmium-Pyrene Contamination

以红树植物秋茄[kAndElIA ObOVATA(S.l.)yOng)]为研究试材,通过镉(Cd)和芘(Pyr)交互胁迫盆栽实验,研究秋茄体内酚类化合物对Cd-Pyr复合污染的响应,旨在探讨红树植物通过酚类化合物的调节耐受重金属和PAHS复合污染的作用机制.Cd胁迫含量为0,5,10,20,40Mg/kg,Pyr胁迫含量为2,10,50Mg/kg,二者交互胁迫.结果显示:Cd和Pyr胁迫下秋茄根、茎、叶合成大量的总酚、单宁和缩合单宁,含量均随着胁迫含量增大呈现上升趋势.各组织总酚、单宁和缩合单宁含量均表现出茎>叶>根.高含量Cd-Pyr复合胁迫下根、茎和叶的总酚、单宁和缩合单宁含量显著高于同一水平Cd胁迫组.根和叶中的总酚、单宁及缩合单宁的含量与相同器官中Cd的含量均呈显著正相关,可推测复合污染背景下总酚、单宁和缩合单宁参与了秋茄根和叶对Cd的螯合,增强了秋茄对Cd的耐性.In recent years,with the rapid urbanization and industrialization,many pollutants are discharged into mangrove ecosystems.Heavy metals and polycyclic aromatic hydrocarbons are particularly common in mangrove ecosystems.It is meaningful to study the response of mangrove plants to heavy metals-polycyclic aromatic hydrocarbons,which can evaluate correctly the tolerance mechanisms of mangrove plant under combined pollutions.To explore the tolerance mechanisms of phenolic compounds of mangrove plant under combined contaminations of heavy metals and polycyclic aromatic hydrocarbons,the responses of phenolic compounds in Kandelia obovata(S.L.)Yong under Cd and pyrene(Pyr)combined contamination were studied by apot experiment.The results showed that a large amount of total phenols,tannins,and condensed tannins were generated in the roots,stems,leaves of K.obovata under Cd/Pyr single stress and Cd and Pyr co-stress,and their contents increased with increasing stress.The order of the contents of total phenols,tannins,and condensed tannins in the plant tissues was as follows:stem>leaf>root.Additionally,the contents of total phenols,tannins,and condensed tannins in roots,stems,and leaves were significantly higher under high levels of co-stress than under single Cd-stress at the same level.There were significant positive correlations between the content of total phenol and Cd concentration in the root and leaf,between the content of tannin and Cd concentration in the root and leaf,and between the content of condensed tannin and Cd concentration in the root and leaf.Therefore,it was suggested that total phenols,tannins and condensed tannins may be involved in Cd tolerance in the roots and leaves of K.obovata under Cd-Pyr combined contamination.国家自然科学基金重点项目(2013CB956504);国家自然科学基金(30970527;31170471;31370516

利用人工湿地修复黔灵湖的研究

黔灵湖水质变坏的根源可以追溯到黔灵湖的上游小关湖,影响水质的根源是养猪废水,其中,主要污染物质为氮、磷、无机质、有机质和微生物等。在小关水库的下游建造人工湿地,种植的植物首先应选择一些去污力强,又宜于本土生长,根系发达,茎叶繁茂,具有耐污能力和抗寒能力、抗病虫能力强的植物,同时还应具有一定的观赏性。用人工湿地技术可以除去上游养猪废水和生活污水中的氮、磷、无机物质和有机物质等,将废水中的氮和磷转化为生物体组织中的氮和磷,从而减少了微生物的大量繁殖形成的"水华"导致黔灵湖水质变坏。同时,通过生物循环可获得一系列的生物产品(小关湖种植凤眼莲、浮萍等浮游植物可以为养猪提供饲料;在小关水库养殖的鱼、虾和贝等和在小关湖下游的湿地种植藕、菱、芡和茨菰等是富有营养的副食品;有些湿地动植物还可入药或作为发展轻工业的重要原材料),还可以美化黔灵公园,从而具有重要的教育意义和实用价值

Effects of Si on the Low Molecular Weight Organic Acid Metabolism of Avicennia marina Under Cd Stress

以红树植物白骨壤为实验材料,通过水培实验,施加不同浓度的SI和Cd,对比研究Cd胁迫下外源SI对白骨壤幼苗低分子质量有机酸代谢的影响,以探讨外源SI对红树植物抗重金属的影响效应和作用机理.结果表明:Cd胁迫显著降低白骨壤幼苗各器官和根系分泌物中低分子质量有机酸含量;SI对有机酸代谢的影响随Cd处理水平不同而不同,在对照(Cd 0Mg/l)和低质量浓度(Cd 0.5Mg/l)处理下,SI对各器官有机酸含量影响不显著或降低其含量,高质量浓度Cd(Cd 5Mg/l)处理下,SI显著增加叶片和茎部有机酸总量,显著增加根系分泌物中柠檬酸含量;白骨壤各器官和根系分泌物有机酸含量两两间显著相关.由此推测SI是白骨壤生长的有益元素,SI缺乏造成的营养胁迫促使植物体内有机酸代谢做出响应;SI促进高质量浓度Cd处理下植物体内的有机酸代谢,对缓解白骨壤Cd毒害效应具有重要意义.Mangrove plants seem to be highly tolerant of high levels of heavy metal pollution.Some researchers have focused on the mechanisms involved in their metal uptake and tolerance.However the important mechanisms involved are still only partially understood.There are higher concentrations of available Si in mangrove sediments.There is increasing evidence that Si has many beneficial effects on mangrove growth and development and can improve heavy metal resistance of mangrove.In order to explore the Si alleviation mechanisms of the toxicity of heavy metal on mangrove,we investigated the effects of Si and Cd on low molecular weight organic acid metabolism of Avicennia marina by pot experiment.The concentration of low molecular weight organic acid in different organs and root exudates were decreased by Cd addition.The effect of Si on low molecular weight organic acid metabolism varied with Cd treatments.Si did not affect or decreased the concentrations of low molecular weight organic acid in different organs and root exudates in 0mg/L and 0.5mg/L Cd treatments.Si increased the total concentrations of low molecular weight organic acid in the stem and leaf and the concentration of citric acid in root exudates under 5mg/L Cd treatments.The correlation analysis showed that there was a significantly positive correlation between the total concentration of low molecular weight organic acid in different organs and root exudates of A.marina.This suggested that Si was beneficial for the healthy growth and development of A.marinaand organic acid metabolism was enhanced by the lack of Si nutrition stress.Si enhanced low molecular weight organic acid metabolism of A.marina under high Cd stress,which may be related to the amelioration by Si of Cd toxicity.国家自然科学基金重点项目(2013CB956504);国家自然科学基金项目(30970527;31170471;31370516

Amplitude analysis of the decays D0 → π+π−π+π− and D0 → π+π−π0π0*

Using e+e− annihilation data corresponding to an integrated luminosity of 2.93 fb−1 taken at the center-of-mass energy √s = 3.773 GeV with the BESIII detector, a joint amplitude analysis is performed on the decays D0 → π+π−π+π− and D0 → π+π−π0π0 (non-η). The fit fractions of individual components are obtained, and large interferences among the dominant components of the decays D0 → a1(1260)π, D0 → π(1300)π, D0 → ρ(770)ρ(770), and D0 → 2(ππ)S are observed in both channels. With the obtained amplitude model, the CP-even fractions of D0 → π+π−π+π− and D0 → π+π−π0π0 (non-η) are determined to be (75.2 ± 1.1stat. ± 1.5syst.) % and (68.9 ± 1.5stat. ± 2.4syst.)%, respectively. The branching fractions of D0 → π+π−π+π− and D0 → π+π−π0π0 (non-η) are measured to be (0.688 ± 0.010stat. ± 0.010syst.)% and (0.951 ± 0.025stat. ± 0.021syst.)%, respectively. The amplitude analysis provides an important model for the binning strategy in measuring the strong phase parameters of D0 → 4π when used to determine the CKM angle γ(φ3) via the B− → DK− decay

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies