东寨港海湾尺度下红树林软体动物时空分布特征及驱动因子

研究海湾尺度下软体动物时空分布特征及驱动因子,为红树林湿地功能保护和管理提供科学依据。于2020年7月至2021年4月对海南东寨港湾口、湾中、湾顶3个典型红树林地点的软体动物的种类组成、物种多样性和群落结构进行四季调查,运用单因素方差分析和Pearson相关性分析软体动物时空格局及其与水环境因子的关系。结果显示：海湾内软体动物物种丰富,共采集到18科31种,优势种为珠带拟蟹守螺（Cerithidea cingulata）、小翼拟蟹守螺（Cerithidea microptera）、绯拟沼螺（Assiminea latericea）、短拟沼螺（Assiminea brevicula）、印澳蛤（Indoaustriella plicifera）、斯氏印澳蛤（Indoaustriella scarlatoi）等;年平均密度和年平均生物量分别为79.6 ind./m²和78.7 g/m²;Margalef丰富度指数（d）、Pielou均匀度指数（J）和Shannon-Wiener多样性指数（H''）分别为1.220±0.188,0.591±0.078,1.815±0.275。海湾内软体动物的密度和生物量存在显著的时空差异：从空间上来看,密度表现为湾口>湾顶>湾中,生物量表现为湾中>湾口>湾顶;从季节上来看,密度差异表现为春季和冬季高于夏季和秋季,生物量则表现为夏季最高。相关性分析结果表明,水体盐度、总溶解固体与软体动物的密度、生物量存在显著的正相关关系,是软体动物群落时空分布特征的主要驱动因子。     

广西珍稀濒危真红树植物小花老鼠簕分布及种群特征

为了填补珍稀濒危真红树植物小花老鼠簕（Acanthus ebracteatus）在广西分布特征的研究空缺,了解其分布、种群大小及群落特征,本文采用野外勘察与样方调查相结合的方法,对广西境内小花老鼠簕可能的分布区域进行全面调查。结果表明：在广西小花老鼠簕仅分布于防城港市江山半岛西南侧和黄竹江中游潮滩,总面积766 m²（分别为686 m²和80 m²）,共1 831株（分别为1 796株和35株）;小花老鼠簕分布在高潮线附近有海漆（Excoecaria agallocha）等相对高大的乔灌木遮挡区域,群落结构分层明显,均呈集群分布;江山半岛小花老鼠簕种群生长相对稳定。广西小花老鼠簕种群分布范围极小,生境狭窄,容易遭到人为干扰,处境严峻,亟需对其进行抢救性保护和物种恢复。     

汾河临汾段湿地植被的数量分类和排序

采用双向指示种分析法(TWINSPAN)和除趋势对应分析法(DCA)对汾河临汾段湿地植被做了分类和排序研究.TW INSPAN分类将湿地植被82个样方分为16个群丛,论述了各群丛的群落学特征.DCA排序结果反映了植物群落类型与环境梯度之间的关系,表明影响群丛分布格局的主导生态因子为土壤水分和海拔高度.     

启东长江口围填海工程对大型底栖动物的影响

为研究启东长江口围填海工程对大型底栖动物的影响,于2019年春季和夏季对围填海工程外侧水域大型底栖动物进行调查,分析群落结构特征、多样性指数及其与环境因子的关系。结果表明：2019年共采集大型底栖动物40种,其中围填海建造的围堤近侧和离岸20 km以外辐射的外侧海域分别采集到大型底栖动物19种和29种;近侧海域和远侧海域的优势种分别为7种和10种,春、夏季共有优势种分别为伶鼬榧螺Oliva mustelina和异足索沙蚕Lumbrineris heteropoda,优势类群为软体动物和环节动物,并且出现小型化、单一化趋势;近侧海域和远侧海域平均生物密度分别为15.36,19.64 ind./m²,平均生物量分别为1.28,3.80 g/m²;2019年近侧海域生物多样性指数较2011年有所下降,低于远侧海域;冗余分析（Redundancy Analysis,RDA）表明,盐度、水深是影响大型底栖动物的主要环境因子。围填海改变了海域的盐度、水深、沉积物等生境,加之围垦后人为频繁的扰动及陆源输入等综合因子的影响,导致大型底栖动物群落结构和多样性指数均发生变动。     

防城港白龙半岛造礁石珊瑚群落的空间分布及特征

为了厘清防城港白龙半岛海域造礁石珊瑚群落分布特征,本研究采用点样线法（Point Intercept Transect,PIT）和样方法于2020年10月对防城港白龙半岛海域造礁石珊瑚群落进行研究。结果表明,该海域造礁石珊瑚群落分布区面积62.1 hm²,根据珊瑚分布的位置,可将其划分3个分布区,其中分布区二面积最大,为54.8 hm²,分布区一和三的面积则分别为2.8,4.5 hm²。鉴定出白龙半岛共有造礁石珊瑚5科8属12种,其中斯氏伯孔珊瑚（Bernardpora stutchburyi）和多孔同星珊瑚（Plesiastrea versipora）为区域优势种;造礁石珊瑚形态主要为表覆状和块状,活珊瑚平均覆盖度为6.6%,平均珊瑚密度为2.12 ind./m²,平均个体大小为170.14 cm²。珊瑚白化率相对较低,平均为0.43%。防城港白龙半岛海域造礁石珊瑚分布面积小,群落种类单一,覆盖度相对较低,尚不成礁。     

晋西北丘陵风沙区人工植被数量分类与排序研究

在群落样方调查的基础上,采用TWINSPAN等级分类和DcA排序相结合的方法,对晋西北丘陵风沙区人工植被群落进行了植被数最分类与排序分析.TWINSPAN分类将晋西北丘陵风沙区人工植被87个样方109个种划分为11个群丛,并论述了各群丛的特征.分类结果很好地反映了植物群丛类型与环境梯度之间的关系,并在DCA二维排序图上得到了较好的验证,DCA排序轴反映了海拔、坡向和土壤水分的梯度变化,结果表明海拔、坡向和土壤水分是决定群落分布的主导因子.     

3种兜兰属植物光合特性的比较研究

通过研究硬叶兜兰(Paphiopedilum micranthum)、带叶兜兰(P.hirsutissimum)和长瓣兜兰(P.dianthum)3种兜兰属植物的光合特性,为其种质资源保育及引种栽培提供理论依据。以广西雅长兰科植物国家级自然保护区内3种兜兰属植物为试验材料,测定其叶片的光响应曲线、CO₂响应曲线以及叶绿素含量,比较3种兜兰光合特性的差异。结果表明：硬叶兜兰、带叶兜兰和长瓣兜兰的最大净光合速率(P_max)分别为2.719 μmol·m^-2·s^-1、1.836 μmol·m^-2·s^-1、2.015 μmol·m^-2·s^-1,光饱和点(LSP)分别为578.74 μmol·m^-2·s^-1 、467.72 μmol·m^-2·s^-1、481.25 μmol·m^-2·s^-1,光补偿点(LCP)均较低,分别为15.65 μmol·m^-2·s^-1、12.79 μmol·m^-2·s^-1、10.34 μmol·m^-2·s^-1,是典型的阴生植物。硬叶兜兰的最大净光合速率(P_max)、CO₂饱和点(CSP)、羧化效率(CE)均显著高于长瓣兜兰和带叶兜兰(P<0.05),硬叶兜兰对CO₂的利用能力更强。叶片叶绿素相对含量(SPAD值)表现为硬叶兜兰(58.13)>长瓣兜兰(55.12)>带叶兜兰(51.88)。3种兜兰属植物的光合能力较弱,对光的利用范围狭窄,在引种栽培时应注意增加荫蔽度。     

海岸工程对北海铁山港红树林大型底栖动物群落的影响

为探究海岸工程对北海铁山港榄根村红树林大型底栖动物群落的影响,本研究于2020年3月对红树林死亡区（D组）、红树林严重退化区（ED组）、活林区（AL组）、对照林区（CK组）等4个区域的大型底栖动物进行定量取样调查。结果显示,4个调查区域大型底栖动物共45种,平均栖息密度和生物量分别为102.4个/m²、147.55 g/m²;Shannon-Wiener多样性指数（H''）、Pielou均匀度指数（J）和Margalef物种丰富度指数（d）分别为2.050,0.735,1.329。单因素方差分析表明,不同区域之间的大型底栖动物栖息密度、生物量、H''、J和d均无显著性差异。但红树林死亡区（D组）和红树林严重退化区（ED组）的大型底栖动物栖息密度、生物量、H''均低于对照林区（CK组）和活林区（AL组）,表明D组和ED组的大型底栖动物群落在海岸工程的影响下受到了更严重的干扰。聚类分析和多维尺度排序（MDS）分析表明,D组与ED组的大型底栖动物群落较为相似,而AL组的大型底栖动物群落则与CK组相似。以上结果表明,海岸工程导致北海铁山港榄根村红树林生态系统受损及其底质环境发生改变,并对该区红树林的大型底栖动物栖息密度、生物量、多样性指数、优势种和群落结构造成了一定负面影响。     

一般有限域GF(pm)上线性码的自同构群

 对单式阵群作一个较详细的研究,并将GF(2^m)上线性码的自同构群的一些结论推广到最一般的有限域GF(p^m)上去,这里的p是任意的素数.     

中国东北地区植被NPP模拟与时空变化分析

利用北方生态过程模型(BEPS)模拟我国东北地区2003-2012年间植被生产力,以森林、 草地通量站点和区域森林样地生产力调查数据两个尺度验证了模型精度,并对其植被净初级生产力（NPP）的时空变化特征及影响因素进行了分析. 结果表明：在站点上,森林的总初级生产力（GPP）与站点观测值的决定系数（R²）为0.94,均方根误差(RMSE)为1.53g·(m²·d)^-1,草地植被的R²与RMSE分别为0.79和0.59g·(m²·d)^{-1;区域森林生产力调查数据处理结果与模拟的森林NPP的决定系数R2=0.84,RMSE=42.73g·(m2·a)-1;研究区域NPP值呈现东北部高西南部低,由东北向西南方向逐级递减的分布格局;10年来,林地NPP增长最为明显,农田增长缓慢,灌木增减不明显,而草地呈弱下降趋势. 温度和太阳辐射是影响东北NPP变化的主要因素,森林干扰是引发局部剧烈变化的重要驱动因素.}     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-