淮河蚌埠段水域浮游甲壳动物的初步研究

2005年春季分两次对淮河蚌埠段水域浮游甲壳动物进行研究.两次调查共记录浮游甲壳动物8种,其中枝角类2属3种,桡足类5属5种.3月份的优势种类为近邻剑水蚤和蚤状氵蚤,3个采样点(蚌埠朝阳大桥、五河分洪闸、浍河节制闸)的浮游甲壳动物密度分别为17.1ind.L-1、7.0ind.L-1、1.8ind.L-1,3个采样点的Shannon-Weiner多样性指数分别为0.68、0.62、0.47.5月份蚌埠朝阳大桥的优势种为近邻剑水蚤、蚤状氵蚤和透明氵蚤,浮游甲壳动物密度为67.5ind.L-1,生物多样性指数为0.76.     

水体铜污染对水葫芦(Eichhornia crassipes)叶绿素荧光及生长的影响

为了解水葫芦(Eichhornia crassipes)在铜污染水体中生存的生理生态机制,设置不同浓度Cu2+(0(CK),0.5,1.0,1.5,2.0 mmol·L-1)对水葫芦进行模拟胁迫培养20 d,观测其叶片叶绿素荧光参数、叶绿素含量、叶氮含量及生物量分配的变化情况.结果显示:不同浓度Cu2+处理后,水葫芦叶片叶绿素荧光参数中叶片初始荧光(Fo)显著小于CK组(P0.05),光化学猝灭系数(qP)与光合电子传递量子效率(ΦPSⅡ)在0.5 mmol·L-1时均显著下降到最低值(P0.05).各个处理水葫芦的最大荧光(Fm)、最大光化学量子产量(Fv/Fm)及非光化学淬灭系数(NPQ值)均显著高于CK组(P0.05).叶片叶绿素含量随Cu2+浓度的增加呈先上升后下降的变化趋势,其中Cu2+浓度为1.0 mmol·L-1时叶绿素含量增加最大,增加比例为14.2%.叶氮含量随Cu2+浓度的增加先上升后下降,其中在Cu2+浓度为1.0 mmol·L-1时,叶氮含量最高,且与其他各处理组均有显著差异(P0.05).水葫芦光合器官生物量比随Cu2+增加呈先上升后下降趋势,而根生物量比却一直上升,导致根冠比持续上升.值得注意的是不同Cu2+处理下水葫芦花生物量比与对照相比均有不同程度的降低.上述研究结果表明水葫芦可能采取先利用再耐受这一机制以抗水体铜污染,同时水葫芦采用降低有性生殖策略响应水体铜污染环境.     

冬季巢湖西半湖的富营养化及污染状况研究——基于浮游藻类的多样性分析

通过网格采样法对冬季巢湖西半湖浮游藻类进行科学采集,运用多种方法对浮游藻类的叶绿素含量、个体数量以及群落结构进行了测试、分析与鉴定,补充了巢湖水体中浮游藻类的多样性资料,系统研究了浮游藻类的分布特征.结果表明,浮游藻类叶绿素含量与藻密度呈正相关,两者分布都呈现由河流入湖口和湖中岛屿附近水体向周边降低的变化趋势.浮游藻类群落以蓝藻门为优势门,优势属主要包括微囊藻属、裸藻属、小球藻属、直链藻属和鱼腥藻属.结合多种生物评价方法,如叶绿素含量评价、特征性藻类污染指数评价和藻类群落的多样性指标(Margalef丰度指数、Shannon Weaver多样性指数、Lloyd Ghelardi均匀度指数和优势度指数)评价,对冬季巢湖西半湖的富营养化和污染状况进行了评估.结果表明,巢湖西半湖水体冬季总体处于中度营养和轻度污染的状态,河流入湖口湖区和湖中岛屿附近水体的富营养化和污染程度较高.     

四川诺水河自然保护区铁溪河段水生生物资源现状及水质评价

【目的】考察四川诺水河自然保护区铁溪河段浮游植物群落特征、水质状况及鱼类资源的现状。【方法】于2020年8月在铁溪河段设置5个采样点，进行浮游植物采集、水体理化指标测定并对鱼类资源现状进行调查，运用Shannon Wiener物种多样性指数（H′）、Margalef物种丰富度指数（D）、Pielou均匀度指数(J)等对采样点水体的浮游植物群落结构特征进行分析，并结合综合水质标识指数法对采样点水体的水质进行综合评价。【结果】1） 共采集到浮游植物4门46属85种（含变种），其中硅藻门（Bacillariophyta）物种数最多。各采样点水体中浮游植物的平均密度为1.046 0个·L-1，平均生物量为1.856×10-1mg·L-1。2） 各采样点水体中浮游植物的H′、D和J的平均值分别为1.875 4、2.508 4和0.745 5。3） S1、S2、S3、S4和S5采样点水体综合水质标识指数依次为：1.500、1.802、1.200、1.500和1.500。4） 共采集到鱼类3目5科15种，其中鲤科（Cyprinidae）鱼类种数最多，占鱼类总种数的60%。【结论】四川诺水河自然保护区铁溪河段水质整体为Ⅰ类水质标准，水体处于轻度污染至中度污染状态。     

抚仙湖浮游动物群落分布特征及其影响因子分析

于2015年对抚仙湖不同湖区的浮游动物群落与水体环境特征开展了逐月调查,共发现浮游动物28种(轮虫21种、枝角类5种及桡足类2种),优势种包括螺形龟甲轮虫(Keratella cochlearis)、长多肢轮虫(Ployarthra dolichoptera)、长额象鼻溞(Bosmina longirostris)、方形网纹溞(Ceriodaphnia quadrangula)、舌状叶镖水蚤(Phyllodiaptomus tunguidus)和温中剑水蚤(Mesocycbps them ocyclopoides Harada)等.浮游动物丰度和生物量全年变化范围分别是1.3~53.2ind·L-1和3.05~306.12μg·L-1;同时,浮游动物的香浓-维纳多样性指数的逐月变化范围较大(1.02~2.19).冗余分析结果进一步表明,浮游动物群落结构逐月变化明显而空间差异较小,水温、钙离子、磷酸盐浓度等对浮游动物群落结构的时空变化产生了较强的驱动作用,而浮游甲壳动物丰度与个体大小的逐月变化明显并受鱼类捕食压力的影响较强.     

镇江滨水区生态修复对浮游生物多样性影响的研究

通过对镇江示范区与非示范区内的浮游生物多样性定量分析,评测其生态修复的效果.分析结果表明,修复工程改善了示范区水体的水质条件,提高了受损生态系统的生物量和群落生物多样性水平.示范区开始出现贫营养型浮游硅藻和敏感型甲壳动物以及清水型原生动物,水网藻等污染水体中从未采获的新种绿藻也有发现.     

蕹菜对富营养化水体的净化及湿地工程示范研究

为探讨浮床培植水蕹菜在大面积富营养化水体中的生长习性、对水体营养盐的移除效果及工程化应用前景,比较了旱地种植和富营养化水体水培蕹菜植株的生物量和根、茎、叶各部位的氮磷含量,并在安徽省池州百荷公园进行了工程示范。结果显示,经过相同生长期,富营养化水培蕹菜单株平均生物量可达1.6 kg,长度达5 m,且水培蕹菜的根系尤其发达,鲜重可占单株总鲜重的35%。旱植蕹菜各部位总氮含量高,水培蕹菜总磷含量高,水培蕹菜根、茎、叶各部位磷/氮比分别为旱植蕹菜对应部位的3.26,3.65和1.51倍。湿地示范工程浮床培植蕹菜一亩水面的生物量达9.3 t,1.08亩蕹菜共移除水中氮93.34 kg、磷7.34 kg;水体总氮含量由工程实施前的3.624 mg·L-1下降至2.181 mg·L-1,总磷由0.187mg·L-1下降至0.144 mg·L-1。研究为利用水生蔬菜进行富营养化水体的生态修复提供了工程化应用的成功案例。对富营养化水体生态修复联产蔬菜的水污染治理策略和今后研究中的关键问题进行了讨论。     

南昌市青山湖浮游植物群落结构的分析

2015年7月、10月和2016年1月、4月通过对青山湖浮游藻类群落结构及水体污染状况进行调查,鉴定出浮游植物有7门73属112种,其中绿藻门最多,共计33属56种,占总种数的50%.浮游植物细胞密度为3.40×108~7.26×108cells·L-1,以蓝藻为主;浮游植物平均生物量为8.105 mg·L-1,以硅藻和绿藻为主;细胞密度优势种为假鱼腥藻、细小平裂藻、美丽星杆藻、二尾栅藻、极小单针藻,生物量优势种包括颗粒直链藻极狭变种、新星形冠盘藻、栅藻、卵囊藻.利用Shannon-Wiener多样性指数、Pielou均匀度指数、Margalef指数及丰富度指数(S)与水体的理化性质相结合对水质作出了评价,结果显示青山湖水质处于中度污染状态.     

海南岛东寨港红树林春、秋季节浮游动物群落的特征研究

为了解东寨港保护区浮游动物的群落结构,于2010年3月和9月在海南东寨港红树林保护区海域的25个采样点采集了浮游动物样本,共鉴定出浮游动物72种,浮游幼虫22种,其中,以甲壳动物最为丰富.3月的优势种共有9种,生物量平均值为98.84 mg·m~(-3),平均丰度为58个体/m~3,Shannon-Wiener多样性指数和Pielou均匀度指数的平均值分别为3.545和0.619.9月的优势种为4种,生物量平均值为202.72 mg·m~(-3),平均丰度为270个体/m3,Shannon-Wiener多样性指数和Pielou均匀度指数的平均值分别为3.123和0.538.在综合分析浮游动物的生物量、丰富度、Shannon-Wiener多样性指数、Pielou均匀度指数后,初步判定东寨港秋季的污染程度大于春季的污染程度,整体海域未受到污染,但近岸受到轻微污染.     

白洋淀浮游植物调查及水质评价

于2009年6月对白洋淀9个点位的浮游植物群落结构及其多样性进行了调查,通过模糊隶属函数对各指数进行标准化处理,对白洋淀水体污染状态进行了评价.调查共监测到浮游植物8门148种,生物量变化范围为23.97×104-1416.5×104个·L-1,平均值为249.49×104个·L-1.优势藻类为衣藻(Chlamydomonas)、狭形纤维藻(Ankistrodesmus angustus)、不定微囊藻(Microcystis,incerta).多样性指数综合评价结果显示,白洋淀水体已经属于中度污染,其中泥李庄、王家寨、烧车淀和鲥鯸淀为β-中污型,而其余的各采样点枣林庄、何庄子、采蒲台、圈头和端村为α-中污型.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the