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1.
为了掌握冬季机场鸟类的活动规律,给机场鸟击防治工作提供理论依据,2018—2019年冬季采用样线法对冬季机场内鸟类活动规律及雪被对鸟类群落的影响进行了研究.结果表明:机场冬季共记录到鸟类19 种,隶属7 目11 科,其中留鸟和冬候鸟是冬季机场鸟类群落的主体,鸟类物种以雀形目杂食性和食谷鸟类为主.上午9:00—10:00鸟类物种数量和个体密度最大.E3区和F3区是鸟类活动最频繁的区域.覆雪后,鸟类个体密度显著增加(P<0.05),但鸟类物种密度显著下降(P<0.05),裸露区是吸引鸟类进入机场活动的主要环境因素.裸露区与过渡区的Beta多样性周转分组高于嵌套分组,表明鸟类有从裸露区向过渡区扩散的能力.雀形目杂食性和食谷鸟类、9:00—10:00和13:00—14:00、E3区和F3区及裸露区应作为机场冬季重点关注和整治的对象、时段和区域.  相似文献   

2.
2009年7—8月采用样线法对三峡库区涪陵段主要城镇7种生境的鸟类群落结构进行了68次调查,共记录鸟类7目23科33种,数量2 182只,其中国家"三有"名录鸟类27种.鸟类区系以东洋界成分为主,广性分布型鸟类10种,城市鸟类的优势种5种,分别为白头鹎、麻雀、八哥、金腰燕、白颊噪鹛.物种多样性指数为2.498 9,均匀度指数为0.714 7,优势度指数为0.117 1.对不同生境鸟类群落特征分析结果表明:①校园的物种数、多样性指数以及均匀性指数均最大,工业区物种数和多样性指数最小,公园广场的均匀性最低;②工业区的优势度指数最大,鸟类群落最不稳定,而校园正好相反;③交通绿化带与相邻的居民区鸟类群落相似性最高,公园广场与农田相似性最低.  相似文献   

3.
涪陵区春季鸟类群落及其对于区域生态保护的意义   总被引:1,自引:1,他引:0  
按照生境特征分为水域、次生林、居民点和农田4种鸟类群落,于2006-2008年采用样线法对涪陵区春季鸟类进行了调查.结果表明,春季共记录到鸟类96种,重要值高的鸟类(200≤IV≤300)4种,广布型鸟类38种.次生林鸟类群落的物种数和Shannon-Wiener指数均最高;水域、水域-农田、次生林-居民点鸟类群落的均匀性指数(Pielou指数)、Jaccard相似性指数、Co-sine相似性指数分别最高.农业生产结构的不合理性和工业污染是影响涪陵区鸟类的主要因素,提倡执行"天然林保护工程".  相似文献   

4.
花坪自然保护区不同生境类型夏季鸟类多样性分析   总被引:1,自引:0,他引:1  
2005年7~8月,采用样线法在广西花坪国家级自然保护区对原生林、次生林、农田-经济林三种生境类型的夏季鸟类群落进行调查,以Shannon-wiener指数、Pielou指数、优势度指数、G-F指数分析鸟类的多样性。结果共记录到鸟类66种,隶属7目29科。原生林的鸟类物种数、物种多样性及G-F指数最高,该群落的鸟类在物种和科属水平上拥有最高的多样性,但是个体数量较少。次生林的鸟类群落密度最高,但是数量集中在几种少数优势种上,多样性指数低。农田-经济林的Pielou指数最高,鸟类群落结构合理、分布均匀、多样性高。保持各类生境空间结构和分布格局,提高植物群落的复杂性,对鸟类多样性及其生存和繁衍有着重要影响。  相似文献   

5.
2013年11月利用路线调查法研究了火烧对机场草地鸟类群落的影响.结果表明:共记录鸟类11种,隶属于5目8科,其中优势种为麻雀(Passer montanus)、短趾百灵(Calandrella cheleensis)和喜鹊(Pica pica).同火烧区域相比,未火烧区具有最高的鸟类密度、Shannon-Weiner指数值(H')和Pielou均匀度指数值(E);火烧显著降低了鸟类群落的密度、物种多样性和均匀度(P0.05),且鸟类密度随着火烧程度的增加而降低;但火烧没有显著改变鸟类群落的物种数(P0.05),火烧区域与未火烧区域鸟类群落物种组成具有较高的相似性.  相似文献   

6.
为有效防范机场鸟击事件的发生,作者从2009年12月-2010年11月对昆明巫家坝国际机场及其周边地区鸟类群落的时空变化规律进行了实地调研,共记录到74种鸟类,分属12目29科,其中留鸟42种,冬候鸟23种,夏候鸟7种,旅鸟2种.不同季节的鸟类种类、密度和Shannon-Weiner多样性指数冬季最低,秋季最高;Pielou均匀度指数则是秋冬季较春夏季为低.调查区域内不同生境鸟类群落的Shannon-Wiener多样性指数,从高到低依次为机场>公园>湿地>居民区,Pielou均匀度指数从高到低则为公园>机场>湿地>居民区;从相似系数来看,机场与湿地间的鸟类群落相似性最高.研究结果表明,昆明机场鸟类群落的季节变动受候鸟迁徙影响严重,秋季应是鸟击的重点防范时段.向化村湿地与机场生境的相似程度最高,对湿地的生态整治应能有效地降低鸟击威胁.据此提出了昆明机场的鸟击防治策略.  相似文献   

7.
巴彦淖尔民航机场鸟击风险评估及鸟击防范   总被引:1,自引:0,他引:1  
为开展鸟击预防工作,及减少鸟击事故的发生,2012年5月至2013年4月,采用样带法和固定半径样点法对巴彦淖尔民航机场及机场周边8km范围内的鸟类进行了系统调查和研究.依据飞行高度、相对数量、相对时间、生境利用率、相对重量组成的综合风险值对鸟类危险等级进行分类.根据不同调查区、不同生境的鸟类群落的分布及环境因子提出了防范对策.记录到的95种鸟类隶属于15目35科,其中繁殖鸟为65种,严重危险鸟类8种,很危险鸟类15种,较危险鸟类17种,一般危险鸟类25种;A区冬季多样性指数最高,B区秋季密度指数较高,C区多样性指数与均匀度指数在全年调查中波动最小,湿地的多样性指数最高、优势度最低,居民区的密度最高,机场草地和居民区生境鸟类构成相似性指数最高;以飞行区内外环境的改造为主,采用既不伤害鸟类、又能让其主动远离机场的人性化驱鸟措施,结合驱鸟技术和设备的使用是达到理想的净空环境的必要条件.  相似文献   

8.
2018年2月24日至5月5日,对宁夏阅海国家湿地公园及周边环境的鸟类种类及数量进行了调查.当地及周边生境主要包括水域、草本沼泽、绿化带、农田4种,在4种生境分别设置样带或样点进行观察.主要观察鸟类的物种和数量,并分别从鸟类的物种组成、居留型、分布型、保护级别、生态型、生境及群落多样性及鸟类动态等角度进行多方面分析.共进行11次调查,记录到鸟类96种,属15目,34科.采用Shannon-wiener指数和Pielou指数来分析当地春季鸟类的物种多样性和均匀性.研究发现宁夏阅海国家湿地公园春季鸟类物种多样性和均匀性较高,但稳定性较差,自然环境因素和人为干扰因素对鸟类栖息影响很大.最后针对鸟类保护提出建议.  相似文献   

9.
【目的】调查和分析常州市金坛生态红线区域内鸟类多样性组成及生态保护现状,为该区生物多样性保护提供依据。【方法】采用样点样线法对常州市金坛生态红线区春、夏、秋季鸟类多样性进行调查,统计不同生境和季节下鸟类种群数量特征,并通过计算Margalef丰富度指数、Shannon-Wiener多样性指数、Simpson指数和Pielou均匀度指数以及群落相似系数分析鸟类在生境和季节上的分布差异。【结果】常州市金坛生态红线区观测到鸟类共13目38科89种,其中雀形目最多(占比50.56%);发现国家二级保护动物4种,江苏省级保护动物36种。鸟类居留型以留鸟为主(占比37.08%),旅鸟最少(占比6.74%)。各生境物种丰富度指数存在显著差异,从高到低依次为湖泊湿地、农田、林地和城市绿地;香农多样性指数和辛普森指数从高到低依次为农田、湖泊湿地、城市绿地和林地;均匀度指数从高到低依次为城市绿地、农田、湖泊湿地和林地,但差异不显著。春、夏、秋季中,夏季鸟类物种和个体数最为丰富,但春季物种丰富度指数较高,其他多样性指数各季节差异不显著。群落相似性方面,林地和农田相似性最高,湖泊湿地与农田差异最大;夏季与秋季...  相似文献   

10.
北京北海公园鸟类多样性季节变化   总被引:3,自引:0,他引:3  
为了解城市公园生物多样性变化特点,于2010年5月-2011年4月在北京北海公园进行鸟类群落调查,每月进行3~4次调查,记录鸟类物种和数量,结合北海公园的自然环境,对鸟类群落结构及其季节变化进行分析.共记录到鸟类42种,隶属于10目22科.其中夏候鸟11种,冬候鸟2种,旅鸟14种,留鸟18种;国家二级保护动物2种,北京市一级保护动物6种,北京市二级保护动物17种.园内鸟类的物种数和数量有季节性差异,鸟类物种数春秋季最高,鸟类数量冬季最多.对3种生境鸟类群落的多样性及均匀性进行了分析,其中树林区鸟类多样性指数最高,为1.3265,景点区鸟类多样性指数最低,为0.4973,鸟类均匀度指数景点区最高,为0.997 6,树林区最低,为0.6355.园内优势种有麻雀Passer montanus、喜鹊Pica pica、灰喜鹊Cyanopica cyana、灰椋鸟Sturnus cineraceus、白头鹎Pycnonotus sinensis大嘴乌鸦Corous macrorh ynchos等.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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。  相似文献   

16.
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.  相似文献   

17.
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-  相似文献   

18.
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-  相似文献   

19.
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  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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